cleanup(worker): drop empty Worker BackgroundService; fix gateway ticket guard

- Remove the no-op Worker BackgroundService and its registration; the process
  is kept alive and does its work through the MassTransit bus and the upload
  intent jobs (their own hosted services)
- Fix the gateway middleware guard to reject on string.IsNullOrEmpty(prefix)
  instead of 'is null', which no longer matched TicketValidator returning
  string.Empty for invalid tickets (invalid tickets skipped the 401 and an
  empty object key could slip through)

Build: 0 warnings, 0 errors.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

.claude/launch.json

@@ -1,24 +0,0 @@
-{
-	"version": "0.0.1",
-	"configurations": [
-		{
-			"name": "musify-web",
-			"runtimeExecutable": "npm",
-			"runtimeArgs": ["--prefix", "web-player", "run", "dev"],
-			"port": 3000,
-			"autoPort": true
-		},
-		{
-			"name": "musify-api",
-			"runtimeExecutable": "dotnet",
-			"runtimeArgs": ["run", "--project", "backend/Hosts/Musify.Api"],
-			"port": 5111
-		},
-		{
-			"name": "musify-streaming-gateway",
-			"runtimeExecutable": "dotnet",
-			"runtimeArgs": ["run", "--project", "backend/Hosts/Musify.StreamingGateway"],
-			"port": 8081
-		}
-	]
-}

.gitattributes

@@ -4,13 +4,6 @@
 # Force LF for shell scripts
 *.sh text eol=lf
 
-# Env templates get `cp`-ed straight into deploy/.env / deploy/.env.prod,
-# which containers (e.g. zitadel-init in deploy/compose.yml) parse with
-# plain shell text tools — keep them LF so a Windows checkout can't
-# reintroduce CRLF into a value that then looks non-empty but isn't.
-.env.example text eol=lf
-.env.prod.example text eol=lf
-
 # Treat common binaries as binary
 *.png binary
 *.jpg binary

.gitea/workflows/ci-cd.yml

@@ -1,127 +0,0 @@
-name: CI/CD
-
-on:
-  push:
-    branches: ['**']
-  pull_request:
-    branches: ['**']
-
-concurrency:
-  group: production-deploy
-  cancel-in-progress: false
-
-jobs:
-  backend-tests:
-    name: BackEnd
-    runs-on: ubuntu-latest
-    timeout-minutes: 20
-    defaults:
-      run:
-        working-directory: backend
-    steps:
-      - uses: actions/checkout@v4
-
-      - uses: actions/setup-dotnet@v4
-        with:
-          dotnet-version: '10.0.x'
-
-      - name: Restore
-        run: dotnet restore Musify.slnx
-
-      - name: Build
-        run: dotnet build Musify.slnx --no-restore -c Release
-
-      - name: Test
-        run: dotnet test Musify.slnx --no-build -c Release
-
-  web-player-checks:
-    name: WebPlayer
-    runs-on: ubuntu-latest
-    timeout-minutes: 15
-    defaults:
-      run:
-        working-directory: web-player
-    steps:
-      - uses: actions/checkout@v4
-
-      - uses: actions/setup-node@v4
-        with:
-          node-version: '22'
-          cache: npm
-          cache-dependency-path: web-player/package-lock.json
-
-      - run: npm ci
-
-      - name: Type-check
-        run: npm run check
-
-      - name: Lint
-        run: npm run lint
-
-  # Runs on the production host itself, through the existing self-hosted
-  # Gitea Actions runner (act_runner), which also carries a "production"
-  # label registered in native (non-docker) mode so its steps see the host's
-  # real Docker daemon directly (Docker socket + a bind-mounted deploy
-  # directory — see deploy/README.md for how that runner is set up).
-  #
-  # DEPLOY_PATH is the persistent clone already on that host (the one whose
-  # deploy/.env.prod is filled in and matches SharedServices/.env.prod) —
-  # deploy reuses it instead of a fresh checkout, since .env.prod is
-  # untracked and only lives there.
-  deploy:
-    name: Deploy
-    needs: [backend-tests, web-player-checks]
-    if: github.ref == 'refs/heads/master' && github.event_name == 'push'
-    runs-on: [production]
-    timeout-minutes: 20
-    env:
-      DEPLOY_PATH: /home/ubuntu/deploys/musify
-      COMPOSE: docker compose --env-file deploy/.env.prod -f deploy/compose.yml -f deploy/compose.prod.yml
-    steps:
-      - name: Pull latest master
-        run: |
-          set -euo pipefail
-          git config --global --add safe.directory "$DEPLOY_PATH"
-          cd "$DEPLOY_PATH"
-          git fetch origin master
-          git reset --hard origin/master
-
-      - name: Generate stream-ticket keys
-        run: |
-          set -euo pipefail
-          cd "$DEPLOY_PATH"
-          $COMPOSE run --rm --no-deps keys-init
-
-      # The migrations are baked into the migrator image, so it is rebuilt on
-      # every deploy (plain `up` would reuse the stale image and re-apply the
-      # old migrations). `run --rm` starts wait-for-postgres, blocks until the
-      # migration finishes and propagates its exit code, so a failed migration
-      # aborts the deploy before the new API is started against an old schema.
-      - name: Migrate database
-        run: |
-          set -euo pipefail
-          cd "$DEPLOY_PATH"
-          $COMPOSE build migrate
-          $COMPOSE run --rm migrate
-
-      # Both jobs verify themselves through the public auth./s3. URLs, served
-      # by the shared edge nginx (Infrastructure's edge/), and are idempotent.
-      - name: Create OIDC app and S3 bucket
-        run: |
-          set -euo pipefail
-          cd "$DEPLOY_PATH"
-          $COMPOSE up -d seaweedfs-init zitadel-init
-          for job in musify-seaweedfs-init musify-zitadel-init; do
-            code=$(docker wait "$job")
-            if [ "$code" != "0" ]; then
-              docker logs "$job"
-              echo "$job exited with $code"
-              exit 1
-            fi
-          done
-
-      - name: Build and start apps
-        run: |
-          set -euo pipefail
-          cd "$DEPLOY_PATH"
-          $COMPOSE --profile apps up -d --build api worker gateway web-player

.github/copilot-instructions.md

@@ -0,0 +1,4 @@
+# Copilot Instructions
+
+## Project Guidelines
+- No crear pruebas/tests si el usuario no lo solicita explícitamente; evitar cambios no pedidos.

.gitignore

@@ -7,9 +7,6 @@ obj/
 *.userosscache
 .vs/
 artifacts/
-TestResults/
-*.trx
-*.coverage
 
 # Rider / VS
 .idea/
@@ -18,14 +15,5 @@ TestResults/
 Thumbs.db
 .DS_Store
 
-# Environment files (deploy/.env, deploy/.env.prod, web-player/.env, ...)
+# Secrets / local
-.env
-.env.*
 *.env
-!.env.example
-!.env.prod.example
-
-# Deploy secrets and runtime state
-deploy/keys/
-deploy/secrets/
-deploy/zitadel/.output/

README.md

@@ -1,55 +0,0 @@
-# Musify
-
-A music streaming app. Upload your own tracks, organize them into playlists
-and albums, and stream them back with a web player built around your
-listening habits: auto-generated mixes, a home feed, search, likes, and an
-Explore page for finding something new.
-
-## What it does
-
-- **Upload and organize your own music**: tracks, albums, cover art, artist credits.
-- **Playlists**, likes, and a "recently played" history.
-- **Mixes**, playlists generated automatically from what you actually listen to.
-- **Explore**, genre browsing and search across tracks, albums, playlists and people.
-- **Real streaming**, not just file downloads: seek, queue, shuffle, repeat.
-- **Accounts via OIDC login**, with an optional anonymous listening mode.
-- Light and dark themes, and a layout that works on both desktop and mobile.
-
-## How it's built
-
-**Backend**: .NET 10, split into a REST API, a background worker, and a
-dedicated streaming gateway.
-- Clean architecture (Domain / Application / Infrastructure) with CQRS (Mediator) and `ErrorOr` results.
-- PostgreSQL via EF Core for metadata. RabbitMQ and MassTransit handle async processing (audio transcoding, thumbnails) with saga-based rollback.
-- SeaweedFS (S3-compatible) for file storage. Uploads and downloads go straight between the client and storage, never through the API.
-- ffmpeg for audio transcoding, ImageSharp for thumbnails.
-- A YARP reverse proxy that streams the audio and checks a signed, short-lived ticket on every request.
-- Zitadel for login (OIDC/OAuth2).
-
-**Web client**: SvelteKit 2 on Svelte 5 (runes), TypeScript, Tailwind 4.
-The session lives on the server, so the backend access token never reaches the browser.
-
-**Infrastructure**: Musify's own apps run from Docker Compose (dev and
-production overlays). Postgres, RabbitMQ, SeaweedFS, Zitadel and Jaeger are
-shared infrastructure that lives in a separate `Infrastructure` git
-repository, used by Musify and by other projects that need the same OIDC
-provider and object storage.
-
-## Project layout
-
-```
-backend/      .NET solution: Api, Worker, StreamingGateway, and the shared Domain/Application/Infrastructure
-web-player/   the SvelteKit web client
-deploy/       Docker Compose stacks for dev and production
-docs/         architecture notes, one file per area
-```
-
-Postgres, Zitadel, SeaweedFS, RabbitMQ and Jaeger are not part of this
-layout. They live in the separate `Infrastructure` repository instead.
-
-## Digging deeper
-
-[docs/](docs/README.md) covers how each piece works and why: architecture,
-authentication, storage, streaming, media processing, and the local dev
-setup. [deploy/README.md](deploy/README.md) has the full instructions for
-running the stack, in development or on a production server.

backend/.dockerignore

@@ -8,5 +8,3 @@
 .claude/
 **/DesignSettings.json
 *.user
-# Test projects: never shipped, no app Dockerfile needs them in its build context.
-Tests/

backend/.editorconfig

@@ -1,79 +0,0 @@
-root = true
-
-[*]
-charset = utf-8
-insert_final_newline = true
-trim_trailing_whitespace = true
-indent_style = space
-
-[*.{csproj,props,targets,slnx,xml}]
-indent_size = 2
-
-[*.json]
-indent_size = 4
-
-[**/Migrations/**.cs]
-generated_code = true
-
-[*.cs]
-indent_size = 4
-
-csharp_style_namespace_declarations = block_scoped:warning
-csharp_using_directive_placement = outside_namespace:warning
-dotnet_sort_system_directives_first = true
-dotnet_separate_import_directive_groups = false
-dotnet_diagnostic.IDE0005.severity = warning
-
-dotnet_style_require_accessibility_modifiers = always:warning
-csharp_style_var_for_built_in_types = true:suggestion
-csharp_style_var_when_type_is_apparent = true:suggestion
-csharp_style_var_elsewhere = true:suggestion
-csharp_prefer_braces = when_multiline:warning
-csharp_style_prefer_primary_constructors = true:suggestion
-csharp_style_expression_bodied_methods = when_on_single_line:suggestion
-dotnet_style_prefer_collection_expression = when_types_loosely_match:suggestion
-
-# Naming. Roslyn applies the first matching rule in file order, so the specific rules come first.
-# Private fields are _camelCase whatever their modifiers (static, readonly, const).
-dotnet_naming_rule.private_fields.symbols = private_fields
-dotnet_naming_rule.private_fields.style = underscore_camel_case
-dotnet_naming_rule.private_fields.severity = warning
-dotnet_naming_symbols.private_fields.applicable_kinds = field
-dotnet_naming_symbols.private_fields.applicable_accessibilities = private
-dotnet_naming_style.underscore_camel_case.capitalization = camel_case
-dotnet_naming_style.underscore_camel_case.required_prefix = _
-
-# Non-private fields (constants, static readonly, etc.) are PascalCase.
-dotnet_naming_rule.other_fields.symbols = other_fields
-dotnet_naming_rule.other_fields.style = pascal_case
-dotnet_naming_rule.other_fields.severity = warning
-dotnet_naming_symbols.other_fields.applicable_kinds = field
-dotnet_naming_symbols.other_fields.applicable_accessibilities = public, internal, protected, protected_internal, private_protected
-dotnet_naming_style.pascal_case.capitalization = pascal_case
-
-dotnet_naming_rule.interfaces.symbols = interfaces
-dotnet_naming_rule.interfaces.style = interface_style
-dotnet_naming_rule.interfaces.severity = warning
-dotnet_naming_symbols.interfaces.applicable_kinds = interface
-dotnet_naming_style.interface_style.capitalization = pascal_case
-dotnet_naming_style.interface_style.required_prefix = I
-
-dotnet_naming_rule.types_and_members.symbols = types_and_members
-dotnet_naming_rule.types_and_members.style = pascal_case
-dotnet_naming_rule.types_and_members.severity = warning
-dotnet_naming_symbols.types_and_members.applicable_kinds = class, struct, enum, delegate, property, method, event
-dotnet_naming_symbols.types_and_members.applicable_accessibilities = *
-
-# CA1848/CA1873 would turn every log call into a [LoggerMessage] source-generated method; CA1716 flags the
-# EF-style IDatabase.Set<T>() and the Musify.Application.Shared namespace, whose names are deliberate.
-dotnet_diagnostic.CA1848.severity = suggestion
-dotnet_diagnostic.CA1873.severity = suggestion
-dotnet_diagnostic.CA1716.severity = suggestion
-# The routing slip builders are stateless services resolved from DI; they stay instance members.
-dotnet_diagnostic.CA1822.severity = suggestion
-
-# Test names follow Method_Scenario_Expected.
-[Tests/**.cs]
-dotnet_diagnostic.CA1707.severity = none
-# xUnit collection fixtures are conventionally named ...Collection.
-dotnet_diagnostic.CA1711.severity = none

backend/CLAUDE.md

@@ -1,58 +0,0 @@
-# Musify: backend
-
-.NET 10 solution (`Musify.slnx`): `Core/` (Domain, Application, Infrastructure), `Hosts/` (Api, Worker, StreamingGateway) and `Tests/`. Architecture and flows are in `../docs/`.
-
-## Commands
-
-Run from `backend/`.
-
-```sh
-dotnet build Musify.slnx            # warnings are errors, including unused usings (IDE0005)
-dotnet test Musify.slnx             # Infrastructure and Api tests need Docker (Testcontainers)
-dotnet format Musify.slnx --verify-no-changes
-```
-
-- Read the totals of `dotnet test` (`total:`, `succeeded:`) before trusting it; don't chain it with `&&` into a commit.
-- EF migrations: `dotnet ef migrations add <Name> --project Core/Musify.Infrastructure --startup-project Core/Musify.Infrastructure` (set `Database__ConnectionString` to any value). A model change needs a migration; the entity model lives in `ModelConfiguration.Apply`, which the in-memory test database reuses.
-- An HTTP contract change (routes, DTOs, responses) needs the web-player schema regenerated (`web-player/src/lib/api/schema.d.ts`, from `/openapi/v1.json`) and `npm run check` clean.
-- A MassTransit message change (events, routing slip arguments, process kinds) means the queues must be drained before deploying; note it in the commit.
-
-## Style
-
-- Block-scoped namespaces (`namespace X { }`; file-scoped `namespace X;` is not allowed), usings outside the namespace and sorted (`.editorconfig` enforces it).
-- Private fields are `_camelCase` whatever their modifiers (including `static readonly` and `const`); non-private constants and static fields, types, methods and properties are PascalCase; interfaces start with `I`; explicit accessibility. Enforced by `.editorconfig` (IDE1006).
-- `ArgumentNullException.ThrowIfNull(x)` without `nameof`.
-- Use `PlayList` (not `Playlist`) in code; configuration POCOs end in `Configuration`; injected services are named after their type (`storageService`).
-- User-facing strings are in English (the web-player owns translation).
-- Trim stored names; normalized columns go through `TextNormalizer.Normalize`.
-- Format ids and numbers with `CultureInfo.InvariantCulture`; put `CancellationToken` last.
-
-## Application layer
-
-- One file per use case, `<Feature>/<UseCase>.cs`, holding the record and its handler; responses go in `Responses/`.
-- Errors come from `AppErrors` (`NotFound`, `Forbidden` = 403 for "not the owner", `Conflict`). `Error.Unauthorized` (401) only means "not signed in". The success value is `Result.Success`; the API maps it to 204.
-- Handlers that cannot fail return plain types. Lists are paginated through `PageRequest` / `ToPaginatedAsync`, ordered with an `Id` tiebreak, and public reads return only `LifeCycleStatus.Active` rows.
-- Owned-entity operations go through `FindOwnedAsync` (non-active entities are not found).
-- No try/catch around `SaveChangesAsync` or `PublishAsync` in handlers: the outbox makes publish + save atomic. Infrastructure either handles an error or lets it propagate; never log and rethrow.
-- List query records keep `int PageNumber, int PageSize`; the API binds them through `PageQuery` and validates them with `PageQueryValidator`.
-
-## API layer
-
-- Routes: `{id:guid}` for the resource, `{trackId:guid}` for sub-resources, `{id:long}` / `{userId:long}` for user ids.
-- Every endpoint returns `IResult` (`Results.Ok` when the handler cannot fail, `ToHttpResult()` otherwise).
-- Validation limits live in `Validators/Limits.cs`; the database column length wins when a limit disagrees with the web-player. Upload allow-lists are in `Validators/Uploads.cs`.
-- `.WithSummary(...)` is sentence case without a trailing period.
-
-## Infrastructure and hosts
-
-- MassTransit routing slips are built from `RoutingSlips.Create` / `AddStep` / `TrackFaults`; activities for the three owner types share generic bases (`MarkLifeCycleActivity<T>`, `DeleteEntityActivity<T>`, `UpdatePicturesActivity<T>`).
-- Recurring work is Hangfire (`RecurringJobsRegistrar`); intervals are in seconds and rounded up to whole minutes.
-- The Worker calls `AddApplication` and validates its service container on build, so any handler dependency must be registered there. Shared config sections in its `appsettings.json` mirror the API's.
-- The StreamingGateway references neither Application nor Infrastructure and keeps its own options.
-
-## Tests
-
-- xUnit v3; pass `TestContext.Current.CancellationToken` to methods that take a token (analyzer xUnit1051).
-- Test names are `Method_Scenario_Expected`.
-- Application tests use the in-memory SQLite `TestDatabase`; Infrastructure and Api tests use Testcontainers (Postgres, SeaweedFS). MassTransit sagas and consumers are tested on the MassTransit test harness.
-- `Infrastructure` exposes its internals to `Musify.Infrastructure.Tests`.

backend/Core/Musify.Application/Albums/AddTracksToAlbum.cs

@@ -1,78 +0,0 @@
-using ErrorOr;
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Microsoft.Extensions.Logging;
-using Musify.Application.Contracts;
-using Musify.Application.Shared;
-using Musify.Domain.Entities;
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.Albums
-{
-    /// <summary>Appends your own tracks to an album in the given order, skipping the ones it already has.</summary>
-    public record AddTracksToAlbumCommand(long UserId, Guid AlbumId, IReadOnlyList<Guid> TrackIds)
-        : ICommand<ErrorOr<Success>>;
-
-    public class AddTracksToAlbumCommandHandler(
-        IDatabase database,
-        ILogger<AddTracksToAlbumCommandHandler> logger)
-        : ICommandHandler<AddTracksToAlbumCommand, ErrorOr<Success>>
-    {
-        public async ValueTask<ErrorOr<Success>> Handle(AddTracksToAlbumCommand request, CancellationToken cancellationToken)
-        {
-            var album = await database.Albums.FindOwnedAsync(request.AlbumId, request.UserId, cancellationToken);
-            if (album.IsError)
-                return album.Errors;
-
-            var requestedIds = request.TrackIds.Distinct().ToList();
-
-            var tracks = await database.Tracks
-                .AsNoTracking()
-                .Where(track => requestedIds.Contains(track.Id) && track.LifeCycleStatus == LifeCycleStatus.Active)
-                .Select(track => new { track.Id, track.OwnerUserId })
-                .ToListAsync(cancellationToken);
-
-            var missing = requestedIds.FirstOrDefault(id => tracks.All(track => track.Id != id));
-            if (missing != Guid.Empty)
-                return AppErrors.NotFound("Track", missing);
-
-            var foreign = tracks.FirstOrDefault(track => track.OwnerUserId != request.UserId);
-            if (foreign != null)
-                return AppErrors.Forbidden("Track", foreign.Id);
-
-            var alreadyInAlbum = await database.AlbumHasTracks
-                .AsNoTracking()
-                .Where(link => link.AlbumId == request.AlbumId && requestedIds.Contains(link.TrackId))
-                .Select(link => link.TrackId)
-                .ToListAsync(cancellationToken);
-
-            var toAdd = requestedIds.Where(id => !alreadyInAlbum.Contains(id)).ToList();
-            if (toAdd.Count == 0)
-                return Result.Success;
-
-            // Album track numbers are user-visible, so they start at 1.
-            var nextTrackNumber = (await database.AlbumHasTracks
-                .Where(link => link.AlbumId == request.AlbumId)
-                .MaxAsync(link => (int?)link.TrackNumber, cancellationToken) ?? 0) + 1;
-
-            foreach (var trackId in toAdd)
-            {
-                await database.AlbumHasTracks.AddAsync(new AlbumHasTrack
-                {
-                    AlbumId = request.AlbumId,
-                    TrackId = trackId,
-                    TrackNumber = nextTrackNumber++
-                }, cancellationToken);
-            }
-
-            var saved = await database.TrySaveChangesAsync(
-                AppErrors.Conflict("Album.ConcurrentChange", "The album changed while adding tracks. Try again."), cancellationToken);
-            if (saved.IsError)
-                return saved;
-
-            logger.LogInformation("Added {Count} tracks to album {AlbumId}", toAdd.Count, request.AlbumId);
-
-            return Result.Success;
-        }
-    }
-}

backend/Core/Musify.Application/Albums/CreateAlbum.cs

@@ -1,73 +0,0 @@
-using ErrorOr;
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Microsoft.Extensions.Logging;
-using Musify.Application.Albums.Responses;
-using Musify.Application.Configuration;
-using Musify.Application.Contracts;
-using Musify.Application.Events;
-using Musify.Application.Pictures;
-using Musify.Application.Services;
-using Musify.Application.Shared;
-using Musify.Domain.Entities;
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.Albums
-{
-    public record CreateAlbumCommand(
-        long UserId,
-        string Title,
-        string? Description,
-        int? ReleaseYear,
-        Guid PictureIntentId)
-        : ICommand<ErrorOr<AlbumApplicationResponse>>;
-
-    public class CreateAlbumCommandHandler(
-        IEventBus eventBus,
-        IDatabase database,
-        UploadIntentValidator uploadIntentValidator,
-        ILogger<CreateAlbumCommandHandler> logger,
-        AlbumConfiguration albumConfiguration)
-        : ICommandHandler<CreateAlbumCommand, ErrorOr<AlbumApplicationResponse>>
-    {
-        public async ValueTask<ErrorOr<AlbumApplicationResponse>> Handle(CreateAlbumCommand request, CancellationToken cancellationToken)
-        {
-            var userExists = await database.Users
-                .AsNoTracking()
-                .AnyAsync(user => user.Id == request.UserId, cancellationToken);
-            if (!userExists)
-                return AppErrors.NotFound("User", request.UserId);
-
-            var prepared = await PictureSourceChange.PrepareAsync(
-                uploadIntentValidator, request.PictureIntentId, request.UserId, UploadIntentPurpose.AlbumPicture, albumConfiguration, cancellationToken);
-            if (prepared.IsError)
-                return prepared.Errors;
-
-            var picture = prepared.Value;
-            var title = request.Title.Trim();
-
-            var album = new Album
-            {
-                OwnerUserId = request.UserId,
-                Title = title,
-                NormalizedTitle = TextNormalizer.Normalize(title),
-                Description = request.Description,
-                ReleaseYear = request.ReleaseYear,
-                Pictures = picture.Pictures
-            };
-
-            await database.Albums.AddAsync(album, cancellationToken);
-
-            await eventBus.PublishAsync(
-                new CreateAlbumResourcesEvent(
-                    album.Id, picture.Intent.Id, picture.Intent.Bucket, picture.Intent.Key, picture.FinalKey, picture.Sizes),
-                cancellationToken);
-
-            await database.SaveChangesAsync(cancellationToken);
-
-            logger.LogInformation("Created album {AlbumId} for user {UserId}", album.Id, request.UserId);
-
-            return AlbumApplicationResponse.FromEntity(album, trackCount: 0);
-        }
-    }
-}

backend/Core/Musify.Application/Albums/DeleteAlbum.cs

@@ -1,37 +0,0 @@
-using ErrorOr;
-using Mediator;
-using Microsoft.Extensions.Logging;
-using Musify.Application.Contracts;
-using Musify.Application.Events;
-using Musify.Application.Shared;
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.Albums
-{
-    public record DeleteAlbumCommand(long UserId, Guid AlbumId)
-        : ICommand<ErrorOr<Success>>;
-
-    public class DeleteAlbumCommandHandler(
-        IDatabase database,
-        IEventBus eventBus,
-        ILogger<DeleteAlbumCommandHandler> logger)
-        : ICommandHandler<DeleteAlbumCommand, ErrorOr<Success>>
-    {
-        public async ValueTask<ErrorOr<Success>> Handle(DeleteAlbumCommand request, CancellationToken cancellationToken)
-        {
-            var found = await database.Albums.FindOwnedAsync(request.AlbumId, request.UserId, cancellationToken);
-            if (found.IsError)
-                return found.Errors;
-
-            var album = found.Value;
-            album.LifeCycleStatus = LifeCycleStatus.Removing;
-
-            await eventBus.PublishAsync(new DeleteAlbumEvent(album.Id, request.UserId), cancellationToken);
-            await database.SaveChangesAsync(cancellationToken);
-
-            logger.LogInformation("Marked album {AlbumId} as removing", request.AlbumId);
-
-            return Result.Success;
-        }
-    }
-}

backend/Core/Musify.Application/Albums/GetAlbumById.cs

@@ -1,30 +0,0 @@
-using ErrorOr;
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Musify.Application.Albums.Responses;
-using Musify.Application.Contracts;
-using Musify.Application.Shared;
-
-namespace Musify.Application.Albums
-{
-    public record GetAlbumByIdQuery(Guid Id)
-        : IQuery<ErrorOr<AlbumApplicationResponse>>;
-
-    public class GetAlbumByIdQueryHandler(IDatabase database)
-        : IQueryHandler<GetAlbumByIdQuery, ErrorOr<AlbumApplicationResponse>>
-    {
-        public async ValueTask<ErrorOr<AlbumApplicationResponse>> Handle(GetAlbumByIdQuery request, CancellationToken cancellationToken)
-        {
-            var album = await database.Albums
-                .AsNoTracking()
-                .Active()
-                .Where(a => a.Id == request.Id)
-                .SelectResponse()
-                .SingleOrDefaultAsync(cancellationToken);
-
-            return album == null
-                ? AppErrors.NotFound("Album", request.Id)
-                : album;
-        }
-    }
-}

backend/Core/Musify.Application/Albums/GetAlbumTracks.cs

@@ -1,39 +0,0 @@
-using ErrorOr;
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Musify.Application.Albums.Responses;
-using Musify.Application.Contracts;
-using Musify.Application.Shared;
-using Musify.Application.Tracks.Responses;
-
-namespace Musify.Application.Albums
-{
-    public record GetAlbumTracksQuery(
-        Guid AlbumId,
-        int PageNumber,
-        int PageSize)
-        : IQuery<ErrorOr<PaginatedResponse<TrackApplicationResponse>>>;
-
-    public class GetAlbumTracksQueryHandler(IDatabase database)
-        : IQueryHandler<GetAlbumTracksQuery, ErrorOr<PaginatedResponse<TrackApplicationResponse>>>
-    {
-        public async ValueTask<ErrorOr<PaginatedResponse<TrackApplicationResponse>>> Handle(GetAlbumTracksQuery request, CancellationToken cancellationToken)
-        {
-            var albumExists = await database.Albums
-                .AsNoTracking()
-                .Active()
-                .AnyAsync(album => album.Id == request.AlbumId, cancellationToken);
-            if (!albumExists)
-                return AppErrors.NotFound("Album", request.AlbumId);
-
-            return await database.AlbumHasTracks
-                .AsNoTracking()
-                .Where(albumTrack => albumTrack.AlbumId == request.AlbumId && albumTrack.Track.LifeCycleStatus == Domain.ValueObjects.LifeCycleStatus.Active)
-                .OrderBy(albumTrack => albumTrack.TrackNumber)
-                .ThenBy(albumTrack => albumTrack.Id)
-                .Select(albumTrack => albumTrack.Track)
-                .SelectResponse()
-                .ToPaginatedAsync(new PageRequest(request.PageNumber, request.PageSize), cancellationToken);
-        }
-    }
-}

backend/Core/Musify.Application/Albums/GetAlbums.cs

@@ -1,34 +0,0 @@
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Musify.Application.Albums.Responses;
-using Musify.Application.Contracts;
-using Musify.Application.Shared;
-
-namespace Musify.Application.Albums
-{
-    public record GetAlbumsQuery(string? Title, int PageNumber, int PageSize)
-        : IQuery<PaginatedResponse<AlbumApplicationResponse>>;
-
-    public class GetAlbumsQueryHandler(IDatabase database)
-        : IQueryHandler<GetAlbumsQuery, PaginatedResponse<AlbumApplicationResponse>>
-    {
-        public async ValueTask<PaginatedResponse<AlbumApplicationResponse>> Handle(GetAlbumsQuery request, CancellationToken cancellationToken)
-        {
-            var albumsQuery = database.Albums
-                .AsNoTracking()
-                .Active();
-
-            if (!string.IsNullOrWhiteSpace(request.Title))
-            {
-                var normalizedTitle = TextNormalizer.Normalize(request.Title);
-                albumsQuery = albumsQuery.Where(album => album.NormalizedTitle.Contains(normalizedTitle));
-            }
-
-            return await albumsQuery
-                .OrderByDescending(album => album.CreatedAt)
-                .ThenBy(album => album.Id)
-                .SelectResponse()
-                .ToPaginatedAsync(new PageRequest(request.PageNumber, request.PageSize), cancellationToken);
-        }
-    }
-}

backend/Core/Musify.Application/Albums/GetAlbumsByUserId.cs

@@ -1,34 +0,0 @@
-using ErrorOr;
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Musify.Application.Albums.Responses;
-using Musify.Application.Contracts;
-using Musify.Application.Shared;
-
-namespace Musify.Application.Albums
-{
-    public record GetAlbumsByUserIdQuery(long UserId, int PageNumber, int PageSize)
-        : IQuery<ErrorOr<PaginatedResponse<AlbumApplicationResponse>>>;
-
-    public class GetAlbumsByUserIdQueryHandler(IDatabase database)
-        : IQueryHandler<GetAlbumsByUserIdQuery, ErrorOr<PaginatedResponse<AlbumApplicationResponse>>>
-    {
-        public async ValueTask<ErrorOr<PaginatedResponse<AlbumApplicationResponse>>> Handle(GetAlbumsByUserIdQuery request, CancellationToken cancellationToken)
-        {
-            var userExists = await database.Users
-                .AsNoTracking()
-                .AnyAsync(user => user.Id == request.UserId, cancellationToken);
-            if (!userExists)
-                return AppErrors.NotFound("User", request.UserId);
-
-            return await database.Albums
-                .AsNoTracking()
-                .Active()
-                .Where(album => album.OwnerUserId == request.UserId)
-                .OrderByDescending(album => album.CreatedAt)
-                .ThenBy(album => album.Id)
-                .SelectResponse()
-                .ToPaginatedAsync(new PageRequest(request.PageNumber, request.PageSize), cancellationToken);
-        }
-    }
-}

backend/Core/Musify.Application/Albums/GetRecentlyListenedAlbums.cs

@@ -1,52 +0,0 @@
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Musify.Application.Albums.Responses;
-using Musify.Application.Contracts;
-
-namespace Musify.Application.Albums
-{
-    public record GetRecentlyListenedAlbumsQuery(long UserId, int Limit)
-        : IQuery<IReadOnlyList<AlbumApplicationResponse>>;
-
-    public class GetRecentlyListenedAlbumsQueryHandler(IDatabase database)
-        : IQueryHandler<GetRecentlyListenedAlbumsQuery, IReadOnlyList<AlbumApplicationResponse>>
-    {
-        public async ValueTask<IReadOnlyList<AlbumApplicationResponse>> Handle(GetRecentlyListenedAlbumsQuery request, CancellationToken cancellationToken)
-        {
-            var listens = database.ListeningHistories
-                .AsNoTracking()
-                .Where(history => history.UserId == request.UserId && history.IsCounted);
-
-            var ranked = await database.AlbumHasTracks
-                .AsNoTracking()
-                .Where(albumTrack => albumTrack.Album.LifeCycleStatus == Domain.ValueObjects.LifeCycleStatus.Active)
-                .Join(
-                    listens,
-                    albumTrack => albumTrack.TrackId,
-                    history => history.TrackId,
-                    (albumTrack, history) => new { albumTrack.AlbumId, history.ListenedAt })
-                .GroupBy(entry => entry.AlbumId)
-                .Select(group => new { AlbumId = group.Key, LastListenedAt = group.Max(entry => entry.ListenedAt) })
-                .OrderByDescending(entry => entry.LastListenedAt)
-                .ThenBy(entry => entry.AlbumId)
-                .Take(request.Limit)
-                .ToListAsync(cancellationToken);
-
-            if (ranked.Count == 0)
-                return [];
-
-            var albumIds = ranked.Select(entry => entry.AlbumId).ToList();
-
-            var albumsById = await database.Albums
-                .AsNoTracking()
-                .Where(album => albumIds.Contains(album.Id))
-                .SelectResponse()
-                .ToDictionaryAsync(album => album.Id, cancellationToken);
-
-            return ranked
-                .Where(entry => albumsById.ContainsKey(entry.AlbumId))
-                .Select(entry => albumsById[entry.AlbumId])
-                .ToList();
-        }
-    }
-}

backend/Core/Musify.Application/Albums/RemoveTrackFromAlbum.cs

@@ -1,46 +0,0 @@
-using ErrorOr;
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Microsoft.Extensions.Logging;
-using Musify.Application.Contracts;
-using Musify.Application.Shared;
-
-namespace Musify.Application.Albums
-{
-    public record RemoveTrackFromAlbumCommand(long UserId, Guid AlbumId, Guid TrackId)
-        : ICommand<ErrorOr<Success>>;
-
-    public class RemoveTrackFromAlbumCommandHandler(
-        IDatabase database,
-        ILogger<RemoveTrackFromAlbumCommandHandler> logger)
-        : ICommandHandler<RemoveTrackFromAlbumCommand, ErrorOr<Success>>
-    {
-        public async ValueTask<ErrorOr<Success>> Handle(RemoveTrackFromAlbumCommand request, CancellationToken cancellationToken)
-        {
-            var album = await database.Albums.FindOwnedAsync(request.AlbumId, request.UserId, cancellationToken);
-            if (album.IsError)
-                return album.Errors;
-
-            var albumTracks = await database.AlbumHasTracks
-                .Where(albumTrack => albumTrack.AlbumId == request.AlbumId)
-                .OrderBy(albumTrack => albumTrack.TrackNumber)
-                .ToListAsync(cancellationToken);
-
-            var link = albumTracks.SingleOrDefault(albumTrack => albumTrack.TrackId == request.TrackId);
-            if (link == null)
-                return Error.NotFound("Album.TrackNotFound", "Track is not in the album.");
-
-            database.AlbumHasTracks.Remove(link);
-
-            var trackNumber = 1;
-            foreach (var remaining in albumTracks.Where(albumTrack => albumTrack.Id != link.Id))
-                remaining.TrackNumber = trackNumber++;
-
-            await database.SaveChangesAsync(cancellationToken);
-
-            logger.LogInformation("Removed track {TrackId} from album {AlbumId}", request.TrackId, request.AlbumId);
-
-            return Result.Success;
-        }
-    }
-}

backend/Core/Musify.Application/Albums/RequestAlbumPictureUpload.cs

@@ -1,25 +0,0 @@
-using ErrorOr;
-using Mediator;
-using Musify.Application.Configuration;
-using Musify.Application.Pictures.Responses;
-using Musify.Application.Services;
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.Albums
-{
-    public record RequestAlbumPictureUploadCommand(
-        long UserId,
-        string FileType,
-        string ContentType,
-        long? ExpectedSizeBytes = null)
-        : ICommand<ErrorOr<PictureUploadResponse>>;
-
-    public class RequestAlbumPictureUploadCommandHandler(UploadIntentIssuer issuer, AlbumConfiguration albumConfiguration)
-        : ICommandHandler<RequestAlbumPictureUploadCommand, ErrorOr<PictureUploadResponse>>
-    {
-        public async ValueTask<ErrorOr<PictureUploadResponse>> Handle(RequestAlbumPictureUploadCommand request, CancellationToken cancellationToken) =>
-            await issuer.IssuePictureAsync(
-                request.UserId, UploadIntentPurpose.AlbumPicture, albumConfiguration,
-                request.FileType, request.ContentType, request.ExpectedSizeBytes, cancellationToken);
-    }
-}

backend/Core/Musify.Application/Albums/Responses/AlbumApplicationResponse.cs

@@ -1,41 +0,0 @@
-using Musify.Domain.Entities;
-
-namespace Musify.Application.Albums.Responses
-{
-    public record AlbumApplicationResponse(
-        Guid Id,
-        string Title,
-        string? Description,
-        int? ReleaseYear,
-        long OwnerUserId,
-        int TrackCount,
-        string? SmallImageKeyName,
-        string? MediumImageKeyName,
-        string? LargeImageKeyName,
-        DateTime CreatedAt,
-        DateTime UpdatedAt,
-        IReadOnlyList<Guid> CoverTrackIds)
-    {
-        public const int CoverTrackCount = AlbumProjections.CoverTrackCount;
-
-        public static AlbumApplicationResponse FromEntity(
-            Album album,
-            int trackCount,
-            IReadOnlyList<Guid>? coverTrackIds = null)
-        {
-            return new AlbumApplicationResponse(
-                album.Id,
-                album.Title,
-                album.Description,
-                album.ReleaseYear,
-                album.OwnerUserId,
-                trackCount,
-                album.Pictures?.SmallName,
-                album.Pictures?.MediumName,
-                album.Pictures?.LargeName,
-                album.CreatedAt,
-                album.UpdatedAt,
-                coverTrackIds ?? []);
-        }
-    }
-}

backend/Core/Musify.Application/Albums/Responses/AlbumProjections.cs

@@ -1,32 +0,0 @@
-using Musify.Domain.Entities;
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.Albums.Responses
-{
-    public static class AlbumProjections
-    {
-        public const int CoverTrackCount = 4;
-
-        public static IQueryable<Album> Active(this IQueryable<Album> query) =>
-            query.Where(album => album.LifeCycleStatus == LifeCycleStatus.Active);
-
-        public static IQueryable<AlbumApplicationResponse> SelectResponse(this IQueryable<Album> query) =>
-            query.Select(album => new AlbumApplicationResponse(
-                album.Id,
-                album.Title,
-                album.Description,
-                album.ReleaseYear,
-                album.OwnerUserId,
-                album.AlbumTracks.Count,
-                album.Pictures!.SmallName,
-                album.Pictures!.MediumName,
-                album.Pictures!.LargeName,
-                album.CreatedAt,
-                album.UpdatedAt,
-                album.AlbumTracks
-                    .OrderBy(albumTrack => albumTrack.TrackNumber)
-                    .Take(CoverTrackCount)
-                    .Select(albumTrack => albumTrack.TrackId)
-                    .ToList()));
-    }
-}

backend/Core/Musify.Application/Albums/UpdateAlbum.cs

@@ -1,74 +0,0 @@
-using ErrorOr;
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Microsoft.Extensions.Logging;
-using Musify.Application.Albums.Responses;
-using Musify.Application.Configuration;
-using Musify.Application.Contracts;
-using Musify.Application.Events;
-using Musify.Application.Pictures;
-using Musify.Application.Services;
-using Musify.Application.Shared;
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.Albums
-{
-    public record UpdateAlbumCommand(
-        long UserId,
-        Guid AlbumId,
-        string Title,
-        string? Description,
-        int? ReleaseYear,
-        Guid? NewPictureIntentId)
-        : ICommand<ErrorOr<AlbumApplicationResponse>>;
-
-    public class UpdateAlbumCommandHandler(
-        IEventBus eventBus,
-        IDatabase database,
-        UploadIntentValidator uploadIntentValidator,
-        ILogger<UpdateAlbumCommandHandler> logger,
-        AlbumConfiguration albumConfiguration)
-        : ICommandHandler<UpdateAlbumCommand, ErrorOr<AlbumApplicationResponse>>
-    {
-        public async ValueTask<ErrorOr<AlbumApplicationResponse>> Handle(UpdateAlbumCommand request, CancellationToken cancellationToken)
-        {
-            var found = await database.Albums.FindOwnedAsync(request.AlbumId, request.UserId, cancellationToken);
-            if (found.IsError)
-                return found.Errors;
-
-            var album = found.Value;
-            var title = request.Title.Trim();
-
-            album.Title = title;
-            album.NormalizedTitle = TextNormalizer.Normalize(title);
-            album.Description = request.Description;
-            album.ReleaseYear = request.ReleaseYear;
-
-            if (request.NewPictureIntentId is { } intentId)
-            {
-                var prepared = await PictureSourceChange.PrepareAsync(
-                    uploadIntentValidator, intentId, request.UserId, UploadIntentPurpose.AlbumPicture, albumConfiguration, cancellationToken);
-                if (prepared.IsError)
-                    return prepared.Errors;
-
-                var picture = prepared.Value;
-                album.Pictures = picture.Pictures;
-
-                await eventBus.PublishAsync(
-                    new UpdateAlbumPictureSourceEvent(
-                        album.Id, picture.Intent.Id, picture.Intent.Bucket, picture.Intent.Key, picture.FinalKey, picture.Sizes),
-                    cancellationToken);
-            }
-
-            await database.SaveChangesAsync(cancellationToken);
-
-            logger.LogInformation("Updated album {AlbumId}", album.Id);
-
-            return await database.Albums
-                .AsNoTracking()
-                .Where(a => a.Id == album.Id)
-                .SelectResponse()
-                .SingleAsync(cancellationToken);
-        }
-    }
-}

backend/Core/Musify.Application/ApplicationDependencyInjection.cs

@@ -1,29 +0,0 @@
-using Microsoft.Extensions.Configuration;
-using Microsoft.Extensions.DependencyInjection;
-using Musify.Application.Configuration;
-using Musify.Application.Services;
-
-namespace Musify.Application
-{
-    public static class ApplicationDependencyInjection
-    {
-        public static IServiceCollection AddApplication(this IServiceCollection services, IConfiguration configuration)
-        {
-            services.AddMediator();
-            services.AddScoped<UploadIntentValidator>();
-            services.AddScoped<UploadIntentIssuer>();
-            services.AddScoped<TrackStreamIssuer>();
-
-            services.AddValidatedOptions<ApplicationStorageConfiguration>(configuration);
-            services.AddValidatedOptions<PlayListConfiguration>(configuration);
-            services.AddValidatedOptions<AlbumConfiguration>(configuration);
-            services.AddValidatedOptions<TrackConfiguration>(configuration);
-            services.AddValidatedOptions<MixConfiguration>(configuration);
-            services.AddValidatedOptions<StreamGatewayConfiguration>(configuration);
-            services.AddValidatedOptions<UploadIntentConfiguration>(configuration);
-            services.AddValidatedOptions<PlaybackConfiguration>(configuration);
-
-            return services;
-        }
-    }
-}

backend/Core/Musify.Application/Configuration/AlbumConfiguration.cs

@@ -1,15 +0,0 @@
-using System.ComponentModel.DataAnnotations;
-
-namespace Musify.Application.Configuration
-{
-    public class AlbumConfiguration : IConfigurationOptions, IPictureOwnerConfiguration
-    {
-        public static string SectionName => "Album";
-
-        [Required]
-        public PictureRoutes Routes { get; set; } = new() { ParentFolder = "Albums" };
-
-        [Required]
-        public PictureSizes PicturesSizes { get; set; } = new();
-    }
-}

backend/Core/Musify.Application/Configuration/ConfigurationDependencyInjection.cs

@@ -1,30 +0,0 @@
-using Microsoft.Extensions.Configuration;
-using Microsoft.Extensions.DependencyInjection;
-using Microsoft.Extensions.Options;
-
-namespace Musify.Application.Configuration
-{
-    public static class ConfigurationDependencyInjection
-    {
-        public static IServiceCollection AddValidatedOptions<T>(this IServiceCollection services, IConfiguration configuration)
-            where T : class, IConfigurationOptions =>
-            services.AddValidatedOptions<T>(configuration, T.SectionName);
-
-        public static IServiceCollection AddValidatedOptions<T>(
-            this IServiceCollection services,
-            IConfiguration configuration,
-            string sectionName)
-            where T : class
-        {
-            services
-                .AddOptionsWithValidateOnStart<T>()
-                .Bind(configuration.GetRequiredSection(sectionName))
-                .ValidateDataAnnotations();
-
-            services.AddSingleton(serviceProvider =>
-                serviceProvider.GetRequiredService<IOptions<T>>().Value);
-
-            return services;
-        }
-    }
-}

backend/Core/Musify.Application/Configuration/GetPlaybackPublicConfig.cs

@@ -1,17 +0,0 @@
-using Mediator;
-using Musify.Application.Configuration.Responses;
-
-namespace Musify.Application.Configuration
-{
-
-    public record GetPlaybackPublicConfigQuery : IQuery<PlaybackPublicConfigResponse>;
-
-    public class GetPlaybackPublicConfigQueryHandler(PlaybackConfiguration playbackConfiguration)
-        : IQueryHandler<GetPlaybackPublicConfigQuery, PlaybackPublicConfigResponse>
-    {
-        public ValueTask<PlaybackPublicConfigResponse> Handle(GetPlaybackPublicConfigQuery query, CancellationToken cancellationToken) =>
-            ValueTask.FromResult(new PlaybackPublicConfigResponse(
-                playbackConfiguration.AllowAnonymousListening,
-                playbackConfiguration.AnonymousFragmentSeconds));
-    }
-}

backend/Core/Musify.Application/Configuration/IConfigurationOptions.cs

@@ -1,7 +0,0 @@
-namespace Musify.Application.Configuration
-{
-    public interface IConfigurationOptions
-    {
-        public static abstract string SectionName { get; }
-    }
-}

backend/Core/Musify.Application/Configuration/MixConfiguration.cs

@@ -1,12 +0,0 @@
-using System.ComponentModel.DataAnnotations;
-
-namespace Musify.Application.Configuration
-{
-    public class MixConfiguration : IConfigurationOptions
-    {
-        public static string SectionName => "Mix";
-
-        [Range(4, 100)]
-        public int ItemsPerMix { get; set; } = 12;
-    }
-}

backend/Core/Musify.Application/Configuration/Pictures.cs

@@ -1,92 +0,0 @@
-using System.ComponentModel.DataAnnotations;
-using System.Globalization;
-using Musify.Application.Shared;
-
-namespace Musify.Application.Configuration
-{
-    public enum PictureSize
-    {
-        Small,
-        Medium,
-        Large
-    }
-
-    public class PictureRoutes
-    {
-        [Required]
-        public string UploadsFolder { get; set; } = "uploads";
-
-        [Required]
-        public string ParentFolder { get; set; } = string.Empty;
-
-        [Required]
-        public string OriginalPicturesFolder { get; set; } = "OriginalPictures";
-
-        [Required]
-        public string SmallPicturesFolder { get; set; } = "SmallPictures";
-
-        [Required]
-        public string MediumPicturesFolder { get; set; } = "MediumPictures";
-
-        [Required]
-        public string LargePicturesFolder { get; set; } = "LargePictures";
-
-        public string FolderPath(PictureSize size) => StorageKey.Combine(ParentFolder, size switch
-        {
-            PictureSize.Small => SmallPicturesFolder,
-            PictureSize.Medium => MediumPicturesFolder,
-            PictureSize.Large => LargePicturesFolder,
-            _ => throw new ArgumentOutOfRangeException(nameof(size), size, null)
-        });
-
-        public string BuildPicturePath(PictureSize size, string pictureName) => StorageKey.Combine(FolderPath(size), pictureName);
-
-        public string BuildOriginalPicturePath(long userId, string pictureName) =>
-            StorageKey.Combine(UploadsFolder, userId.ToString(CultureInfo.InvariantCulture), ParentFolder, OriginalPicturesFolder, pictureName);
-
-        public string BuildTempPath(string tempRootPrefix, long userId, string objectName) =>
-            StorageKey.Combine(tempRootPrefix, userId.ToString(CultureInfo.InvariantCulture), ParentFolder, objectName);
-    }
-
-    public class PictureSizes
-    {
-        [Range(1, 1024)]
-        public int SmallWidth { get; set; } = 128;
-
-        [Range(1, 1024)]
-        public int SmallHeight { get; set; } = 128;
-
-        [Range(1, 1024)]
-        public int MediumWidth { get; set; } = 256;
-
-        [Range(1, 1024)]
-        public int MediumHeight { get; set; } = 256;
-
-        [Range(1, 1024)]
-        public int LargeWidth { get; set; } = 512;
-
-        [Range(1, 1024)]
-        public int LargeHeight { get; set; } = 512;
-
-        public ImageSizes ToImageSizes(PictureRoutes routes) => new(
-            new ImageSize(routes.FolderPath(PictureSize.Small), SmallWidth, SmallHeight),
-            new ImageSize(routes.FolderPath(PictureSize.Medium), MediumWidth, MediumHeight),
-            new ImageSize(routes.FolderPath(PictureSize.Large), LargeWidth, LargeHeight));
-    }
-
-    public interface IPictureOwnerConfiguration
-    {
-        public PictureRoutes Routes { get; }
-
-        public PictureSizes PicturesSizes { get; }
-    }
-
-    public static class PictureSizeParser
-    {
-        /// <summary>Parses the <c>size</c> query value; anything unknown means <see cref="PictureSize.Medium"/>.</summary>
-        public static PictureSize Parse(string? value) =>
-            Enum.TryParse<PictureSize>(value, ignoreCase: true, out var size) && Enum.IsDefined(size)
-                ? size
-                : PictureSize.Medium;
-    }
-}

backend/Core/Musify.Application/Configuration/PlayListConfiguration.cs

@@ -1,15 +0,0 @@
-using System.ComponentModel.DataAnnotations;
-
-namespace Musify.Application.Configuration
-{
-    public class PlayListConfiguration : IConfigurationOptions, IPictureOwnerConfiguration
-    {
-        public static string SectionName => "PlayList";
-
-        [Required]
-        public PictureRoutes Routes { get; set; } = new() { ParentFolder = "PlayLists" };
-
-        [Required]
-        public PictureSizes PicturesSizes { get; set; } = new();
-    }
-}

backend/Core/Musify.Application/Configuration/PlaybackConfiguration.cs

@@ -1,18 +0,0 @@
-using System.ComponentModel.DataAnnotations;
-
-namespace Musify.Application.Configuration
-{
-
-    public sealed class PlaybackConfiguration : IConfigurationOptions
-    {
-        public static string SectionName => "Playback";
-
-        public bool AllowAnonymousListening { get; set; }
-
-        [Range(0, 3600)]
-        public int AnonymousFragmentSeconds { get; set; }
-
-        [Range(1, int.MaxValue)]
-        public int EstimatedAudioBytesPerSecond { get; set; } = 16_000;
-    }
-}

backend/Core/Musify.Application/Configuration/Responses/PlaybackPublicConfigResponse.cs

@@ -1,5 +0,0 @@
-namespace Musify.Application.Configuration.Responses
-{
-
-    public record PlaybackPublicConfigResponse(bool AllowAnonymousListening, int AnonymousFragmentSeconds);
-}

backend/Core/Musify.Application/Configuration/TrackConfiguration.cs

@@ -1,57 +0,0 @@
-using System.ComponentModel.DataAnnotations;
-using System.Globalization;
-using Musify.Application.Shared;
-
-namespace Musify.Application.Configuration
-{
-    public class TrackConfiguration : IConfigurationOptions, IPictureOwnerConfiguration
-    {
-        public static string SectionName => "Track";
-
-        [Required]
-        public TrackRoutes Routes { get; set; } = new();
-
-        [Required]
-        public PictureSizes PicturesSizes { get; set; } = new();
-
-        PictureRoutes IPictureOwnerConfiguration.Routes => Routes;
-    }
-
-    public class TrackRoutes : PictureRoutes
-    {
-        public TrackRoutes()
-        {
-            ParentFolder = "Tracks";
-        }
-
-        [Required]
-        public string PresetOriginalPicture { get; set; } = "PresetOriginalPicture.webp";
-
-        [Required]
-        public string PresetSmallPicture { get; set; } = "PresetSmallPicture.webp";
-
-        [Required]
-        public string PresetMediumPicture { get; set; } = "PresetMediumPicture.webp";
-
-        [Required]
-        public string PresetLargePicture { get; set; } = "PresetLargePicture.webp";
-
-        [Required]
-        public string OriginalAudiosFolder { get; set; } = "OriginalAudios";
-
-        [Required]
-        public string ProcessedAudiosFolder { get; set; } = "ProcessedAudios";
-
-        public string PresetSmallPicturePath => StorageKey.Combine(ParentFolder, PresetSmallPicture);
-
-        public string PresetMediumPicturePath => StorageKey.Combine(ParentFolder, PresetMediumPicture);
-
-        public string PresetLargePicturePath => StorageKey.Combine(ParentFolder, PresetLargePicture);
-
-        public string BuildOriginalAudioPath(long userId, string audioName) =>
-            StorageKey.Combine(UploadsFolder, userId.ToString(CultureInfo.InvariantCulture), ParentFolder, OriginalAudiosFolder, audioName);
-
-        public string BuildProcessedAudioPath(string folderName) =>
-            StorageKey.Combine(ParentFolder, ProcessedAudiosFolder, folderName);
-    }
-}

backend/Core/Musify.Application/Contracts/AudioTranscodeResult.cs

@@ -1,4 +0,0 @@
-namespace Musify.Application.Contracts
-{
-    public record AudioTranscodeResult(int StatusCode, TimeSpan Duration);
-}

backend/Core/Musify.Application/Contracts/IAudioTranscoderService.cs

@@ -1,7 +0,0 @@
-namespace Musify.Application.Contracts
-{
-    public interface IAudioTranscoderService
-    {
-        public Task<AudioTranscodeResult> TranscodeToAudioFileAsync(Stream audioStream, string destinationPath, CancellationToken cancellationToken);
-    }
-}

backend/Core/Musify.Application/Contracts/IDatabase.cs

@@ -1,43 +0,0 @@
-using ErrorOr;
-using Microsoft.EntityFrameworkCore;
-using Musify.Domain.Entities;
-
-namespace Musify.Application.Contracts
-{
-    public interface IDatabase
-    {
-        public DbSet<User> Users { get; }
-
-        public DbSet<PlayList> PlayLists { get; }
-
-        public DbSet<Album> Albums { get; }
-
-        public DbSet<AlbumHasTrack> AlbumHasTracks { get; }
-
-        public DbSet<Track> Tracks { get; }
-
-        public DbSet<PlayListHasTrack> PlayListHasTracks { get; }
-
-        public DbSet<Mix> Mixes { get; }
-
-        public DbSet<MixItem> MixItems { get; }
-
-        public DbSet<UploadIntent> UploadIntents { get; }
-
-        public DbSet<ListeningHistory> ListeningHistories { get; }
-
-        public DbSet<TrackLike> TrackLikes { get; }
-
-        public DbSet<TrackTag> TrackTags { get; }
-
-        public DbSet<UserFollow> UserFollows { get; }
-
-        public Task<IDatabaseTransaction> BeginTransactionAsync(System.Data.IsolationLevel isolationLevel, CancellationToken cancellationToken);
-
-        public DbSet<TEntity> Set<TEntity>() where TEntity : class;
-
-        public Task<int> SaveChangesAsync(CancellationToken cancellationToken);
-
-        public Task<ErrorOr<Success>> TrySaveChangesAsync(Error onUniqueViolation, CancellationToken cancellationToken);
-    }
-}

backend/Core/Musify.Application/Contracts/IEventBus.cs

@@ -1,7 +0,0 @@
-namespace Musify.Application.Contracts
-{
-    public interface IEventBus
-    {
-        public Task PublishAsync<T>(T message, CancellationToken cancellationToken) where T : class;
-    }
-}

backend/Core/Musify.Application/Contracts/IPictureService.cs

@@ -1,7 +0,0 @@
-namespace Musify.Application.Contracts
-{
-    public interface IPictureService
-    {
-        public Task<Stream> ResizePictureAsWebpAsync(Stream pictureStream, int width, int height, CancellationToken cancellationToken);
-    }
-}

backend/Core/Musify.Application/Contracts/IStorageService.cs

@@ -1,25 +0,0 @@
-namespace Musify.Application.Contracts
-{
-    public interface IStorageService
-    {
-        /// <summary>Opens an object for reading, or returns null when it does not exist.</summary>
-        public Task<Stream?> GetFileAsync(string bucket, string key, CancellationToken cancellationToken);
-
-        public Task<ObjectMetaData?> HeadObjectAsync(string bucket, string key, CancellationToken cancellationToken);
-
-        public Task<string> GetUploadUrlAsync(string bucket, string key, string contentType, TimeSpan expirationTime, bool preventOverwrite = true, CancellationToken cancellationToken = default);
-
-        public Task UploadFileAsync(string filePath, string bucket, string key, CancellationToken cancellationToken);
-
-        public Task UploadFileAsync(Stream sourceStream, string contentType, string bucket, string key, CancellationToken cancellationToken);
-
-        public Task<IReadOnlyList<string>> TransferFilesAsync(string sourceDirectory, string bucket, string route, CancellationToken cancellationToken);
-
-        public Task RemoveFileAsync(string bucket, string key, CancellationToken cancellationToken);
-
-        public Task CopyFileAsync(string sourceBucket, string sourceKey, string destinationBucket, string destinationKey,
-            CancellationToken cancellationToken);
-
-        public IAsyncEnumerable<StorageObject> ListObjectsAsync(string bucket, string prefix, CancellationToken cancellationToken);
-    }
-}

backend/Core/Musify.Application/Events/AlbumPictureProcessed.cs

@@ -1,4 +0,0 @@
-namespace Musify.Application.Events
-{
-    public record AlbumPictureProcessed(Guid AlbumId);
-}

backend/Core/Musify.Application/Events/AlbumPictureProcessingFailed.cs

@@ -1,4 +0,0 @@
-namespace Musify.Application.Events
-{
-    public record AlbumPictureProcessingFailed(Guid AlbumId);
-}

backend/Core/Musify.Application/Events/AlbumProcessingFailed.cs

@@ -1,7 +0,0 @@
-namespace Musify.Application.Events
-{
-    public record AlbumProcessingFailed(
-        Guid AlbumId,
-        string? Bucket,
-        string? PictureKey);
-}

backend/Core/Musify.Application/Events/CreateAlbumResourcesEvent.cs

@@ -1,12 +0,0 @@
-using Musify.Application.Shared;
-
-namespace Musify.Application.Events
-{
-    public record CreateAlbumResourcesEvent(
-        Guid AlbumId,
-        Guid PictureIntentId,
-        string Bucket,
-        string PictureSourceKey,
-        string PictureDestinationKey,
-        ImageSizes Sizes);
-}

backend/Core/Musify.Application/Events/DeleteAlbumEvent.cs

@@ -1,6 +0,0 @@
-namespace Musify.Application.Events
-{
-    public record DeleteAlbumEvent(
-        Guid AlbumId,
-        long UserId);
-}

backend/Core/Musify.Application/Events/UpdateAlbumPictureEvent.cs

@@ -1,10 +0,0 @@
-using Musify.Application.Shared;
-
-namespace Musify.Application.Events
-{
-    public record UpdateAlbumPictureEvent(
-        Guid AlbumId,
-        string Bucket,
-        string SourceKey,
-        ImageSizes Sizes);
-}

backend/Core/Musify.Application/Events/UpdateAlbumPictureSourceEvent.cs

@@ -1,12 +0,0 @@
-using Musify.Application.Shared;
-
-namespace Musify.Application.Events
-{
-    public record UpdateAlbumPictureSourceEvent(
-        Guid AlbumId,
-        Guid PictureIntentId,
-        string Bucket,
-        string PictureSourceKey,
-        string PictureDestinationKey,
-        ImageSizes Sizes);
-}

backend/Core/Musify.Application/Genres/GetAvailableGenres.cs

@@ -1,25 +0,0 @@
-using Mediator;
-using Musify.Application.Genres.Responses;
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.Genres
-{
-    public record GetAvailableGenresQuery : IQuery<IReadOnlyList<AvailableGenreResponse>>;
-
-    public class GetAvailableGenresQueryHandler
-        : IQueryHandler<GetAvailableGenresQuery, IReadOnlyList<AvailableGenreResponse>>
-    {
-        public ValueTask<IReadOnlyList<AvailableGenreResponse>> Handle(GetAvailableGenresQuery request, CancellationToken cancellationToken)
-        {
-            var all = Enum.GetValues<Genre>();
-
-            IReadOnlyList<AvailableGenreResponse> result = all
-                .Select(genre => new AvailableGenreResponse(
-                    genre,
-                    all.Where(other => !GenreCompatibility.AreCompatible(genre, other)).ToList()))
-                .ToList();
-
-            return ValueTask.FromResult(result);
-        }
-    }
-}

backend/Core/Musify.Application/Genres/GetGenres.cs

@@ -1,30 +0,0 @@
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Musify.Application.Contracts;
-using Musify.Application.Genres.Responses;
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.Genres
-{
-    public record GetGenresQuery : IQuery<IReadOnlyList<GenreResponse>>;
-
-    public class GetGenresQueryHandler(IDatabase database)
-        : IQueryHandler<GetGenresQuery, IReadOnlyList<GenreResponse>>
-    {
-        public async ValueTask<IReadOnlyList<GenreResponse>> Handle(GetGenresQuery request, CancellationToken cancellationToken)
-        {
-            var rows = await database.TrackTags
-                .AsNoTracking()
-                .Where(tag => tag.Track.LifeCycleStatus == LifeCycleStatus.Active)
-                .GroupBy(tag => tag.Tag)
-                .Select(group => new { Genre = group.Key, TrackCount = group.Select(tag => tag.TrackId).Distinct().Count() })
-                .ToListAsync(cancellationToken);
-
-            return rows
-                .OrderByDescending(row => row.TrackCount)
-                .ThenBy(row => row.Genre)
-                .Select(row => new GenreResponse(row.Genre, row.TrackCount))
-                .ToList();
-        }
-    }
-}

backend/Core/Musify.Application/Genres/Responses/AvailableGenreResponse.cs

@@ -1,6 +0,0 @@
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.Genres.Responses
-{
-    public record AvailableGenreResponse(Genre Genre, IReadOnlyList<Genre> IncompatibleWith);
-}

backend/Core/Musify.Application/Genres/Responses/GenreResponse.cs

@@ -1,6 +0,0 @@
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.Genres.Responses
-{
-    public record GenreResponse(Genre Genre, int TrackCount);
-}

backend/Core/Musify.Application/Likes/GetLikedTracks.cs

@@ -1,31 +0,0 @@
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Musify.Application.Contracts;
-using Musify.Application.Shared;
-using Musify.Application.Tracks.Responses;
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.Likes
-{
-    public record GetLikedTracksQuery(
-        long UserId,
-        int PageNumber,
-        int PageSize)
-        : IQuery<PaginatedResponse<TrackApplicationResponse>>;
-
-    public class GetLikedTracksQueryHandler(IDatabase database)
-        : IQueryHandler<GetLikedTracksQuery, PaginatedResponse<TrackApplicationResponse>>
-    {
-        public async ValueTask<PaginatedResponse<TrackApplicationResponse>> Handle(GetLikedTracksQuery request, CancellationToken cancellationToken)
-        {
-            return await database.TrackLikes
-                .AsNoTracking()
-                .Where(like => like.UserId == request.UserId && like.Track.LifeCycleStatus == LifeCycleStatus.Active)
-                .OrderByDescending(like => like.CreatedAt)
-                .ThenBy(like => like.Id)
-                .Select(like => like.Track)
-                .SelectResponse()
-                .ToPaginatedAsync(new PageRequest(request.PageNumber, request.PageSize), cancellationToken);
-        }
-    }
-}

backend/Core/Musify.Application/Likes/ToggleTrackLike.cs

@@ -1,59 +0,0 @@
-using ErrorOr;
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Microsoft.Extensions.Logging;
-using Musify.Application.Contracts;
-using Musify.Application.Shared;
-using Musify.Domain.Entities;
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.Likes
-{
-    public record ToggleTrackLikeCommand(long UserId, Guid TrackId)
-        : ICommand<ErrorOr<bool>>;
-
-    public class ToggleTrackLikeCommandHandler(
-        IDatabase database,
-        ILogger<ToggleTrackLikeCommandHandler> logger)
-        : ICommandHandler<ToggleTrackLikeCommand, ErrorOr<bool>>
-    {
-        public async ValueTask<ErrorOr<bool>> Handle(ToggleTrackLikeCommand request, CancellationToken cancellationToken)
-        {
-            var trackExists = await database.Tracks
-                .AsNoTracking()
-                .AnyAsync(t => t.Id == request.TrackId && t.LifeCycleStatus == LifeCycleStatus.Active, cancellationToken);
-            if (!trackExists)
-                return AppErrors.NotFound("Track", request.TrackId);
-
-            var existingLike = await database.TrackLikes
-                .SingleOrDefaultAsync(like => like.UserId == request.UserId && like.TrackId == request.TrackId, cancellationToken);
-
-            bool nowLiked;
-            if (existingLike != null)
-            {
-                database.TrackLikes.Remove(existingLike);
-                nowLiked = false;
-            }
-            else
-            {
-                await database.TrackLikes.AddAsync(new TrackLike
-                {
-                    UserId = request.UserId,
-                    TrackId = request.TrackId
-                }, cancellationToken);
-                nowLiked = true;
-            }
-
-            // A concurrent double click can hit the unique index; the outcome is already in place, so treat it as a no-op.
-            var saved = await database.TrySaveChangesAsync(
-                AppErrors.Conflict("TrackLike.Duplicate", "Track is already liked."), cancellationToken);
-            if (saved.IsError)
-                return true;
-
-            logger.LogInformation("User {UserId} {Action} track {TrackId}",
-                request.UserId, nowLiked ? "liked" : "unliked", request.TrackId);
-
-            return nowLiked;
-        }
-    }
-}

backend/Core/Musify.Application/Mixes/GenerateMixesForUser.cs

@@ -1,131 +0,0 @@
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Microsoft.Extensions.Logging;
-using Musify.Application.Configuration;
-using Musify.Application.Contracts;
-using Musify.Domain.Entities;
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.Mixes
-{
-    public record GenerateMixesForUserCommand(long UserId)
-        : ICommand;
-
-    public class GenerateMixesForUserCommandHandler(
-        IDatabase database,
-        MixConfiguration mixConfiguration,
-        ILogger<GenerateMixesForUserCommandHandler> logger)
-        : ICommandHandler<GenerateMixesForUserCommand>
-    {
-        private sealed record MixDraft(MixKind Kind, IReadOnlyList<Guid> TrackIds);
-
-        public async ValueTask<Unit> Handle(GenerateMixesForUserCommand request, CancellationToken cancellationToken)
-        {
-            var userId = request.UserId;
-
-            var libraryTrackIds = await database.Tracks
-                .AsNoTracking()
-                .Where(track => track.OwnerUserId == userId && track.LifeCycleStatus == LifeCycleStatus.Active)
-                .Select(track => track.Id)
-                .ToListAsync(cancellationToken);
-
-            if (libraryTrackIds.Count == 0)
-            {
-                logger.LogInformation("User {UserId} has no tracks yet, skipping mix generation", userId);
-                return Unit.Value;
-            }
-
-            var historyTrackIds = await database.ListeningHistories
-                .AsNoTracking()
-                .Where(history => history.UserId == userId && history.IsCounted)
-                .Select(history => history.TrackId)
-                .Distinct()
-                .ToListAsync(cancellationToken);
-
-            var historySet = new HashSet<Guid>(historyTrackIds);
-            var unheardTrackIds = libraryTrackIds.Where(id => !historySet.Contains(id)).ToList();
-
-            var drafts = new List<MixDraft>();
-
-            var discovery = Take(Shuffle(unheardTrackIds));
-            if (discovery.Count > 0)
-            {
-                drafts.Add(new MixDraft(MixKind.Discovery, discovery));
-            }
-
-            var daily = Take(Interleave(Shuffle(historyTrackIds), Shuffle(unheardTrackIds)));
-            if (daily.Count > 0)
-            {
-                drafts.Add(new MixDraft(MixKind.Daily, daily));
-            }
-
-            if (drafts.Count == 0)
-            {
-                logger.LogInformation("No candidate songs found for user {UserId}, skipping mix generation", userId);
-                return Unit.Value;
-            }
-
-            await ReplaceMixesAsync(userId, drafts, cancellationToken);
-
-            await database.SaveChangesAsync(cancellationToken);
-
-            logger.LogInformation("Generated {Count} mixes for user {UserId}", drafts.Count, userId);
-            return Unit.Value;
-        }
-
-        private List<Guid> Take(IEnumerable<Guid> trackIds) =>
-            [.. trackIds.Take(mixConfiguration.ItemsPerMix)];
-
-        private static List<Guid> Shuffle(IEnumerable<Guid> trackIds) =>
-            [.. trackIds.OrderBy(_ => Guid.NewGuid())];
-
-        private static List<Guid> Interleave(List<Guid> first, List<Guid> second)
-        {
-            var merged = new List<Guid>(first.Count + second.Count);
-            for (var index = 0; index < Math.Max(first.Count, second.Count); index++)
-            {
-                if (index < first.Count)
-                    merged.Add(first[index]);
-                if (index < second.Count)
-                    merged.Add(second[index]);
-            }
-
-            return merged;
-        }
-
-        private async Task ReplaceMixesAsync(long userId, IReadOnlyList<MixDraft> drafts, CancellationToken cancellationToken)
-        {
-            var previousMixes = await database.Mixes
-                .Where(mix => mix.UserId == userId)
-                .ToListAsync(cancellationToken);
-
-            if (previousMixes.Count > 0)
-            {
-                database.Mixes.RemoveRange(previousMixes);
-            }
-
-            for (var position = 0; position < drafts.Count; position++)
-            {
-                var draft = drafts[position];
-                var mix = new Mix
-                {
-                    UserId = userId,
-                    Kind = draft.Kind,
-                    Position = position
-                };
-
-                await database.Mixes.AddAsync(mix, cancellationToken);
-
-                for (var itemPosition = 0; itemPosition < draft.TrackIds.Count; itemPosition++)
-                {
-                    await database.MixItems.AddAsync(new MixItem
-                    {
-                        MixId = mix.Id,
-                        Position = itemPosition,
-                        TrackId = draft.TrackIds[itemPosition]
-                    }, cancellationToken);
-                }
-            }
-        }
-    }
-}

backend/Core/Musify.Application/Mixes/GetMixById.cs

@@ -1,32 +0,0 @@
-using ErrorOr;
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Musify.Application.Contracts;
-using Musify.Application.Mixes.Responses;
-using Musify.Application.Shared;
-
-namespace Musify.Application.Mixes
-{
-    public record GetMixByIdQuery(long UserId, Guid MixId)
-        : IQuery<ErrorOr<MixApplicationResponse>>;
-
-    public class GetMixByIdQueryHandler(IDatabase database)
-        : IQueryHandler<GetMixByIdQuery, ErrorOr<MixApplicationResponse>>
-    {
-        public async ValueTask<ErrorOr<MixApplicationResponse>> Handle(GetMixByIdQuery request, CancellationToken cancellationToken)
-        {
-            var mix = await database.Mixes
-                .AsNoTracking()
-                .Include(mix => mix.Items)
-                .SingleOrDefaultAsync(mix => mix.Id == request.MixId && mix.UserId == request.UserId, cancellationToken);
-
-            if (mix == null)
-                return AppErrors.NotFound("Mix", request.MixId);
-
-            var orderedItems = mix.Items.OrderBy(item => item.Position).ToList();
-            var items = await MixItemMapper.ToResponsesAsync(database, orderedItems, cancellationToken);
-
-            return new MixApplicationResponse(mix.Id, mix.Kind, items.Count, items);
-        }
-    }
-}

backend/Core/Musify.Application/Mixes/GetMixesByUserId.cs

@@ -1,51 +0,0 @@
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Musify.Application.Contracts;
-using Musify.Application.Mixes.Responses;
-
-namespace Musify.Application.Mixes
-{
-    public record GetMixesByUserIdQuery(long UserId)
-        : IQuery<IReadOnlyList<MixApplicationResponse>>;
-
-    public class GetMixesByUserIdQueryHandler(IDatabase database)
-        : IQueryHandler<GetMixesByUserIdQuery, IReadOnlyList<MixApplicationResponse>>
-    {
-        public async ValueTask<IReadOnlyList<MixApplicationResponse>> Handle(GetMixesByUserIdQuery request, CancellationToken cancellationToken)
-        {
-            var mixes = await database.Mixes
-                .AsNoTracking()
-                .Where(mix => mix.UserId == request.UserId)
-                .Include(mix => mix.Items)
-                .OrderBy(mix => mix.Position)
-                .ThenBy(mix => mix.Id)
-                .ToListAsync(cancellationToken);
-
-            var orderedItemsByMix = mixes.ToDictionary(
-                mix => mix.Id,
-                mix => mix.Items.OrderBy(item => item.Position).ToList());
-
-            var coverItems = orderedItemsByMix.Values
-                .SelectMany(items => items.Take(MixApplicationResponse.CoverItemCount))
-                .ToList();
-            var coverResponses = (await MixItemMapper.ToResponsesAsync(database, coverItems, cancellationToken))
-                .GroupBy(response => response.TrackId)
-                .ToDictionary(group => group.Key, group => group.First());
-
-            var responses = new List<MixApplicationResponse>(mixes.Count);
-            foreach (var mix in mixes)
-            {
-                var orderedItems = orderedItemsByMix[mix.Id];
-                var covers = orderedItems
-                    .Take(MixApplicationResponse.CoverItemCount)
-                    .Where(item => coverResponses.ContainsKey(item.TrackId))
-                    .Select(item => coverResponses[item.TrackId])
-                    .ToList();
-
-                responses.Add(new MixApplicationResponse(mix.Id, mix.Kind, orderedItems.Count, covers));
-            }
-
-            return responses;
-        }
-    }
-}

backend/Core/Musify.Application/Mixes/MixItemMapper.cs

@@ -1,41 +0,0 @@
-using Microsoft.EntityFrameworkCore;
-using Musify.Application.Contracts;
-using Musify.Application.Mixes.Responses;
-using Musify.Domain.Entities;
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.Mixes
-{
-
-    internal static class MixItemMapper
-    {
-        public static async Task<List<MixItemApplicationResponse>> ToResponsesAsync(
-            IDatabase database,
-            IReadOnlyList<MixItem> orderedItems,
-            CancellationToken cancellationToken)
-        {
-            var trackIds = orderedItems.Select(item => item.TrackId).Distinct().ToList();
-
-            var tracksById = await database.Tracks
-                .AsNoTracking()
-                .Include(track => track.Owner)
-                .Where(track => trackIds.Contains(track.Id) && track.LifeCycleStatus == LifeCycleStatus.Active)
-                .Select(track => new { Track = track, ListensCount = track.ListeningHistories.Count(l => l.IsCounted) })
-                .ToDictionaryAsync(x => x.Track.Id, cancellationToken);
-
-            return orderedItems
-                .Where(item => tracksById.ContainsKey(item.TrackId))
-                .Select(item =>
-                {
-                    var entry = tracksById[item.TrackId];
-                    return new MixItemApplicationResponse(
-                        item.TrackId,
-                        entry.Track.Title,
-                        entry.Track.Owner.Name,
-                        entry.Track.DurationSeconds,
-                        entry.ListensCount);
-                })
-                .ToList();
-        }
-    }
-}

backend/Core/Musify.Application/Mixes/Responses/MixApplicationResponse.cs

@@ -1,13 +0,0 @@
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.Mixes.Responses
-{
-    public record MixApplicationResponse(
-        Guid Id,
-        MixKind Kind,
-        int ItemCount,
-        IReadOnlyList<MixItemApplicationResponse> Items)
-    {
-        public const int CoverItemCount = 4;
-    }
-}

backend/Core/Musify.Application/Mixes/Responses/MixItemApplicationResponse.cs

@@ -1,9 +0,0 @@
-namespace Musify.Application.Mixes.Responses
-{
-    public record MixItemApplicationResponse(
-        Guid TrackId,
-        string Title,
-        string? Artist,
-        double DurationSeconds,
-        int ListensCount);
-}

backend/Core/Musify.Application/Pictures/GetCover.cs

@@ -1,76 +0,0 @@
-using ErrorOr;
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using MimeMapping;
-using Musify.Application.Configuration;
-using Musify.Application.Contracts;
-using Musify.Application.Shared;
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.Pictures
-{
-    public enum CoverOwner
-    {
-        Track,
-        Album,
-        PlayList
-    }
-
-    public record GetCoverQuery(CoverOwner Owner, Guid Id, PictureSize Size = PictureSize.Medium)
-        : IQuery<ErrorOr<CoverLocation>>;
-
-    public record CoverLocation(string Bucket, string Key, string ContentType);
-
-    public class GetCoverQueryHandler(
-        IDatabase database,
-        ApplicationStorageConfiguration storageConfiguration,
-        TrackConfiguration trackConfiguration,
-        AlbumConfiguration albumConfiguration,
-        PlayListConfiguration playListConfiguration)
-        : IQueryHandler<GetCoverQuery, ErrorOr<CoverLocation>>
-    {
-        private sealed record CoverSource(long OwnerUserId, string? Original, string? Small, string? Medium, string? Large);
-
-        public async ValueTask<ErrorOr<CoverLocation>> Handle(GetCoverQuery request, CancellationToken cancellationToken)
-        {
-            var (source, routes) = request.Owner switch
-            {
-                CoverOwner.Track => (await database.Tracks.AsNoTracking()
-                    .Where(t => t.Id == request.Id && t.LifeCycleStatus == LifeCycleStatus.Active)
-                    .Select(t => new CoverSource(t.OwnerUserId, t.Pictures.OriginalName, t.Pictures.SmallName, t.Pictures.MediumName, t.Pictures.LargeName))
-                    .SingleOrDefaultAsync(cancellationToken), trackConfiguration.Routes),
-                CoverOwner.Album => (await database.Albums.AsNoTracking()
-                    .Where(a => a.Id == request.Id && a.LifeCycleStatus == LifeCycleStatus.Active && a.Pictures != null)
-                    .Select(a => new CoverSource(a.OwnerUserId, a.Pictures!.OriginalName, a.Pictures.SmallName, a.Pictures.MediumName, a.Pictures.LargeName))
-                    .SingleOrDefaultAsync(cancellationToken), albumConfiguration.Routes),
-                _ => (await database.PlayLists.AsNoTracking()
-                    .Where(p => p.Id == request.Id && p.LifeCycleStatus == LifeCycleStatus.Active && p.Pictures != null)
-                    .Select(p => new CoverSource(p.OwnerUserId, p.Pictures!.OriginalName, p.Pictures.SmallName, p.Pictures.MediumName, p.Pictures.LargeName))
-                    .SingleOrDefaultAsync(cancellationToken), playListConfiguration.Routes)
-            };
-
-            var entity = request.Owner.ToString();
-            if (source == null)
-                return AppErrors.NotFound($"{entity}Cover", request.Id);
-
-            var resizedName = request.Size switch
-            {
-                PictureSize.Small => source.Small,
-                PictureSize.Large => source.Large,
-                _ => source.Medium
-            };
-
-            // The resized files only exist once processing has finished; until then serve the original.
-            var (name, key) = !string.IsNullOrEmpty(resizedName)
-                ? (resizedName, routes.BuildPicturePath(request.Size, resizedName))
-                : !string.IsNullOrEmpty(source.Original)
-                    ? (source.Original, routes.BuildOriginalPicturePath(source.OwnerUserId, source.Original))
-                    : (null, null);
-
-            if (name == null || key == null)
-                return AppErrors.NotFound($"{entity}Cover", request.Id);
-
-            return new CoverLocation(storageConfiguration.Bucket, key, MimeUtility.GetMimeMapping(name));
-        }
-    }
-}

backend/Core/Musify.Application/Pictures/PictureSourceChange.cs

@@ -1,36 +0,0 @@
-using ErrorOr;
-using Musify.Application.Configuration;
-using Musify.Application.Services;
-using Musify.Application.Shared;
-using Musify.Domain.Entities;
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.Pictures
-{
-    /// <summary>What an album or playlist needs to switch to a freshly uploaded picture.</summary>
-    public sealed record PreparedPicture(UploadIntent Intent, EntityPictures Pictures, string FinalKey, ImageSizes Sizes);
-
-    public static class PictureSourceChange
-    {
-        public static async Task<ErrorOr<PreparedPicture>> PrepareAsync(
-            UploadIntentValidator uploadIntentValidator,
-            Guid intentId,
-            long userId,
-            UploadIntentPurpose purpose,
-            IPictureOwnerConfiguration owner,
-            CancellationToken cancellationToken)
-        {
-            var validation = await uploadIntentValidator.ValidateAndLoadAsync(intentId, userId, purpose, cancellationToken);
-            if (validation.IsError)
-                return validation.Errors;
-
-            var intent = validation.Value;
-
-            return new PreparedPicture(
-                intent,
-                EntityPictures.Pending(intent.ObjectName),
-                owner.Routes.BuildOriginalPicturePath(userId, intent.ObjectName),
-                owner.PicturesSizes.ToImageSizes(owner.Routes));
-        }
-    }
-}

backend/Core/Musify.Application/PlayLists/AddTracksToPlayList.cs

@@ -1,74 +0,0 @@
-using ErrorOr;
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Microsoft.Extensions.Logging;
-using Musify.Application.Contracts;
-using Musify.Application.Shared;
-using Musify.Domain.Entities;
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.PlayLists
-{
-    /// <summary>Appends tracks to a playlist in the given order, skipping the ones it already has.</summary>
-    public record AddTracksToPlayListCommand(long UserId, Guid PlayListId, IReadOnlyList<Guid> TrackIds)
-        : ICommand<ErrorOr<Success>>;
-
-    public class AddTracksToPlayListCommandHandler(
-        IDatabase database,
-        ILogger<AddTracksToPlayListCommandHandler> logger)
-        : ICommandHandler<AddTracksToPlayListCommand, ErrorOr<Success>>
-    {
-        public async ValueTask<ErrorOr<Success>> Handle(AddTracksToPlayListCommand request, CancellationToken cancellationToken)
-        {
-            var playList = await database.PlayLists.FindOwnedAsync(request.PlayListId, request.UserId, cancellationToken);
-            if (playList.IsError)
-                return playList.Errors;
-
-            var requestedIds = request.TrackIds.Distinct().ToList();
-
-            var existingIds = await database.Tracks
-                .AsNoTracking()
-                .Where(track => requestedIds.Contains(track.Id) && track.LifeCycleStatus == LifeCycleStatus.Active)
-                .Select(track => track.Id)
-                .ToListAsync(cancellationToken);
-
-            var missing = requestedIds.FirstOrDefault(id => !existingIds.Contains(id));
-            if (missing != Guid.Empty)
-                return AppErrors.NotFound("Track", missing);
-
-            var alreadyInPlayList = await database.PlayListHasTracks
-                .AsNoTracking()
-                .Where(link => link.PlayListId == request.PlayListId && requestedIds.Contains(link.TrackId))
-                .Select(link => link.TrackId)
-                .ToListAsync(cancellationToken);
-
-            var toAdd = requestedIds.Where(id => !alreadyInPlayList.Contains(id)).ToList();
-            if (toAdd.Count == 0)
-                return Result.Success;
-
-            // Playlist positions are internal indexes, so they start at 0.
-            var nextPosition = (await database.PlayListHasTracks
-                .Where(link => link.PlayListId == request.PlayListId)
-                .MaxAsync(link => (int?)link.Position, cancellationToken) ?? -1) + 1;
-
-            foreach (var trackId in toAdd)
-            {
-                await database.PlayListHasTracks.AddAsync(new PlayListHasTrack
-                {
-                    PlayListId = request.PlayListId,
-                    TrackId = trackId,
-                    Position = nextPosition++
-                }, cancellationToken);
-            }
-
-            var saved = await database.TrySaveChangesAsync(
-                AppErrors.Conflict("PlayList.ConcurrentChange", "The playlist changed while adding tracks. Try again."), cancellationToken);
-            if (saved.IsError)
-                return saved;
-
-            logger.LogInformation("Added {Count} tracks to playlist {PlayListId}", toAdd.Count, request.PlayListId);
-
-            return Result.Success;
-        }
-    }
-}

backend/Core/Musify.Application/PlayLists/CreatePlayList.cs

@@ -1,79 +0,0 @@
-using ErrorOr;
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Microsoft.Extensions.Logging;
-using Musify.Application.Configuration;
-using Musify.Application.Contracts;
-using Musify.Application.Events;
-using Musify.Application.Pictures;
-using Musify.Application.PlayLists.Responses;
-using Musify.Application.Services;
-using Musify.Application.Shared;
-using Musify.Domain.Entities;
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.PlayLists
-{
-    public record CreatePlayListCommand(
-        long UserId,
-        string Name,
-        string? Description,
-        Guid? PictureIntentId,
-        PlayListVisibility Visibility = PlayListVisibility.Private)
-        : ICommand<ErrorOr<PlayListApplicationResponse>>;
-
-    public class CreatePlayListCommandHandler(
-        IEventBus eventBus,
-        IDatabase database,
-        UploadIntentValidator uploadIntentValidator,
-        ILogger<CreatePlayListCommandHandler> logger,
-        PlayListConfiguration playListConfiguration)
-        : ICommandHandler<CreatePlayListCommand, ErrorOr<PlayListApplicationResponse>>
-    {
-        public async ValueTask<ErrorOr<PlayListApplicationResponse>> Handle(CreatePlayListCommand request, CancellationToken cancellationToken)
-        {
-            var userExists = await database.Users
-                .AsNoTracking()
-                .AnyAsync(u => u.Id == request.UserId, cancellationToken);
-            if (!userExists)
-                return AppErrors.NotFound("User", request.UserId);
-
-            PreparedPicture? picture = null;
-            if (request.PictureIntentId is { } intentId)
-            {
-                var prepared = await PictureSourceChange.PrepareAsync(
-                    uploadIntentValidator, intentId, request.UserId, UploadIntentPurpose.PlayListPicture, playListConfiguration, cancellationToken);
-                if (prepared.IsError)
-                    return prepared.Errors;
-
-                picture = prepared.Value;
-            }
-
-            var name = request.Name.Trim();
-            var playList = new PlayList
-            {
-                OwnerUserId = request.UserId,
-                Name = name,
-                NormalizedName = TextNormalizer.Normalize(name),
-                Description = string.IsNullOrWhiteSpace(request.Description) ? null : request.Description.Trim(),
-                Pictures = picture?.Pictures,
-                Visibility = request.Visibility
-            };
-            await database.PlayLists.AddAsync(playList, cancellationToken);
-
-            if (picture != null)
-            {
-                await eventBus.PublishAsync(
-                    new CreatePlayListResourcesEvent(
-                        playList.Id, picture.Intent.Id, picture.Intent.Bucket, picture.Intent.Key, picture.FinalKey, picture.Sizes),
-                    cancellationToken);
-            }
-
-            await database.SaveChangesAsync(cancellationToken);
-
-            logger.LogInformation("Created playlist {PlayListId} for user {UserId}", playList.Id, request.UserId);
-
-            return PlayListApplicationResponse.FromEntity(playList);
-        }
-    }
-}

backend/Core/Musify.Application/PlayLists/DeletePlayList.cs

@@ -1,37 +0,0 @@
-using ErrorOr;
-using Mediator;
-using Microsoft.Extensions.Logging;
-using Musify.Application.Contracts;
-using Musify.Application.Events;
-using Musify.Application.Shared;
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.PlayLists
-{
-    public record DeletePlayListCommand(long UserId, Guid PlayListId)
-        : ICommand<ErrorOr<Success>>;
-
-    public class DeletePlayListCommandHandler(
-        IDatabase database,
-        IEventBus eventBus,
-        ILogger<DeletePlayListCommandHandler> logger)
-        : ICommandHandler<DeletePlayListCommand, ErrorOr<Success>>
-    {
-        public async ValueTask<ErrorOr<Success>> Handle(DeletePlayListCommand request, CancellationToken cancellationToken)
-        {
-            var found = await database.PlayLists.FindOwnedAsync(request.PlayListId, request.UserId, cancellationToken);
-            if (found.IsError)
-                return found.Errors;
-
-            var playList = found.Value;
-            playList.LifeCycleStatus = LifeCycleStatus.Removing;
-
-            await eventBus.PublishAsync(new DeletePlayListEvent(playList.Id, request.UserId), cancellationToken);
-            await database.SaveChangesAsync(cancellationToken);
-
-            logger.LogInformation("Marked playlist {PlayListId} as removing", request.PlayListId);
-
-            return Result.Success;
-        }
-    }
-}

backend/Core/Musify.Application/PlayLists/GetPlayListTracks.cs

@@ -1,42 +0,0 @@
-using ErrorOr;
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Musify.Application.Contracts;
-using Musify.Application.PlayLists.Responses;
-using Musify.Application.Shared;
-using Musify.Application.Tracks.Responses;
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.PlayLists
-{
-    public record GetPlayListTracksQuery(
-        Guid PlayListId,
-        int PageNumber,
-        int PageSize,
-        long? ViewerId = null)
-        : IQuery<ErrorOr<PaginatedResponse<TrackApplicationResponse>>>;
-
-    public class GetPlayListTracksQueryHandler(IDatabase database)
-        : IQueryHandler<GetPlayListTracksQuery, ErrorOr<PaginatedResponse<TrackApplicationResponse>>>
-    {
-        public async ValueTask<ErrorOr<PaginatedResponse<TrackApplicationResponse>>> Handle(GetPlayListTracksQuery request, CancellationToken cancellationToken)
-        {
-            var playListVisible = await database.PlayLists
-                .AsNoTracking()
-                .Active()
-                .VisibleTo(request.ViewerId)
-                .AnyAsync(playList => playList.Id == request.PlayListId, cancellationToken);
-            if (!playListVisible)
-                return AppErrors.NotFound("PlayList", request.PlayListId);
-
-            return await database.PlayListHasTracks
-                .AsNoTracking()
-                .Where(playListTrack => playListTrack.PlayListId == request.PlayListId && playListTrack.Track.LifeCycleStatus == LifeCycleStatus.Active)
-                .OrderBy(playListTrack => playListTrack.Position)
-                .ThenBy(playListTrack => playListTrack.Id)
-                .Select(playListTrack => playListTrack.Track)
-                .SelectResponse()
-                .ToPaginatedAsync(new PageRequest(request.PageNumber, request.PageSize), cancellationToken);
-        }
-    }
-}

backend/Core/Musify.Application/PlayLists/GetPlayListsByUserId.cs

@@ -1,41 +0,0 @@
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Musify.Application.Contracts;
-using Musify.Application.PlayLists.Responses;
-using Musify.Application.Shared;
-
-namespace Musify.Application.PlayLists
-{
-    public record GetPlayListsByUserIdQuery(
-        long UserId,
-        string? Name,
-        int PageNumber,
-        int PageSize,
-        long? ViewerId = null)
-        : IQuery<PaginatedResponse<PlayListApplicationResponse>>;
-
-    public class GetPlayListsByUserIdQueryHandler(IDatabase database)
-        : IQueryHandler<GetPlayListsByUserIdQuery, PaginatedResponse<PlayListApplicationResponse>>
-    {
-        public async ValueTask<PaginatedResponse<PlayListApplicationResponse>> Handle(GetPlayListsByUserIdQuery request, CancellationToken cancellationToken)
-        {
-            var playListsQuery = database.PlayLists
-                .AsNoTracking()
-                .Active()
-                .VisibleTo(request.ViewerId)
-                .Where(playList => playList.OwnerUserId == request.UserId);
-
-            if (!string.IsNullOrWhiteSpace(request.Name))
-            {
-                var normalizedName = TextNormalizer.Normalize(request.Name);
-                playListsQuery = playListsQuery.Where(playList => playList.NormalizedName.Contains(normalizedName));
-            }
-
-            return await playListsQuery
-                .OrderBy(playList => playList.CreatedAt)
-                .ThenBy(playList => playList.Id)
-                .SelectResponse()
-                .ToPaginatedAsync(new PageRequest(request.PageNumber, request.PageSize), cancellationToken);
-        }
-    }
-}

backend/Core/Musify.Application/PlayLists/RemoveTrackFromPlayList.cs

@@ -1,46 +0,0 @@
-using ErrorOr;
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Microsoft.Extensions.Logging;
-using Musify.Application.Contracts;
-using Musify.Application.Shared;
-
-namespace Musify.Application.PlayLists
-{
-    public record RemoveTrackFromPlayListCommand(long UserId, Guid PlayListId, Guid TrackId)
-        : ICommand<ErrorOr<Success>>;
-
-    public class RemoveTrackFromPlayListCommandHandler(
-        IDatabase database,
-        ILogger<RemoveTrackFromPlayListCommandHandler> logger)
-        : ICommandHandler<RemoveTrackFromPlayListCommand, ErrorOr<Success>>
-    {
-        public async ValueTask<ErrorOr<Success>> Handle(RemoveTrackFromPlayListCommand request, CancellationToken cancellationToken)
-        {
-            var playList = await database.PlayLists.FindOwnedAsync(request.PlayListId, request.UserId, cancellationToken);
-            if (playList.IsError)
-                return playList.Errors;
-
-            var playListTracks = await database.PlayListHasTracks
-                .Where(plt => plt.PlayListId == request.PlayListId)
-                .OrderBy(plt => plt.Position)
-                .ToListAsync(cancellationToken);
-
-            var link = playListTracks.SingleOrDefault(plt => plt.TrackId == request.TrackId);
-            if (link == null)
-                return Error.NotFound("PlayList.TrackNotFound", "Track is not in the playlist.");
-
-            database.PlayListHasTracks.Remove(link);
-
-            var position = 0;
-            foreach (var remaining in playListTracks.Where(plt => plt.Id != link.Id))
-                remaining.Position = position++;
-
-            await database.SaveChangesAsync(cancellationToken);
-
-            logger.LogInformation("Removed track {TrackId} from playlist {PlayListId}", request.TrackId, request.PlayListId);
-
-            return Result.Success;
-        }
-    }
-}

backend/Core/Musify.Application/PlayLists/RequestPlayListPictureUpload.cs

@@ -1,25 +0,0 @@
-using ErrorOr;
-using Mediator;
-using Musify.Application.Configuration;
-using Musify.Application.Pictures.Responses;
-using Musify.Application.Services;
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.PlayLists
-{
-    public record RequestPlayListPictureUploadCommand(
-        long UserId,
-        string FileType,
-        string ContentType,
-        long? ExpectedSizeBytes = null)
-        : ICommand<ErrorOr<PictureUploadResponse>>;
-
-    public class RequestPlayListPictureUploadCommandHandler(UploadIntentIssuer issuer, PlayListConfiguration playListConfiguration)
-        : ICommandHandler<RequestPlayListPictureUploadCommand, ErrorOr<PictureUploadResponse>>
-    {
-        public async ValueTask<ErrorOr<PictureUploadResponse>> Handle(RequestPlayListPictureUploadCommand request, CancellationToken cancellationToken) =>
-            await issuer.IssuePictureAsync(
-                request.UserId, UploadIntentPurpose.PlayListPicture, playListConfiguration,
-                request.FileType, request.ContentType, request.ExpectedSizeBytes, cancellationToken);
-    }
-}

backend/Core/Musify.Application/PlayLists/Responses/PlayListApplicationResponse.cs

@@ -1,46 +0,0 @@
-using Musify.Domain.Entities;
-using Musify.Domain.ValueObjects;
-
-
-namespace Musify.Application.PlayLists.Responses
-{
-    public record PlayListApplicationResponse(
-        Guid Id,
-        string Name,
-        string? Description,
-        string? SmallImageKeyName,
-        string? MediumImageKeyName,
-        string? LargeImageKeyName,
-        PlayListVisibility Visibility,
-        DateTime CreatedAt,
-        DateTime UpdatedAt,
-        IReadOnlyList<Guid> CoverTrackIds,
-        long OwnerUserId,
-        int TrackCount,
-        double DurationSeconds)
-    {
-        public const int CoverTrackCount = PlayListProjections.CoverTrackCount;
-
-        public static PlayListApplicationResponse FromEntity(
-            PlayList playList,
-            IReadOnlyList<Guid>? coverTrackIds = null,
-            int trackCount = 0,
-            double durationSeconds = 0)
-        {
-            return new PlayListApplicationResponse(
-                playList.Id,
-                playList.Name,
-                playList.Description,
-                playList.Pictures?.SmallName,
-                playList.Pictures?.MediumName,
-                playList.Pictures?.LargeName,
-                playList.Visibility,
-                playList.CreatedAt,
-                playList.UpdatedAt,
-                coverTrackIds ?? [],
-                playList.OwnerUserId,
-                trackCount,
-                durationSeconds);
-        }
-    }
-}

backend/Core/Musify.Application/PlayLists/Responses/PlayListProjections.cs

@@ -1,38 +0,0 @@
-using Musify.Domain.Entities;
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.PlayLists.Responses
-{
-    public static class PlayListProjections
-    {
-        public const int CoverTrackCount = 4;
-
-        public static IQueryable<PlayList> Active(this IQueryable<PlayList> query) =>
-            query.Where(playList => playList.LifeCycleStatus == LifeCycleStatus.Active);
-
-        public static IQueryable<PlayList> VisibleTo(this IQueryable<PlayList> query, long? viewerId) =>
-            query.Where(playList => playList.Visibility == PlayListVisibility.Public || playList.OwnerUserId == viewerId);
-
-        public static IQueryable<PlayListApplicationResponse> SelectResponse(this IQueryable<PlayList> query) =>
-            query.Select(playList => new PlayListApplicationResponse(
-                playList.Id,
-                playList.Name,
-                playList.Description,
-                playList.Pictures!.SmallName,
-                playList.Pictures!.MediumName,
-                playList.Pictures!.LargeName,
-                playList.Visibility,
-                playList.CreatedAt,
-                playList.UpdatedAt,
-                playList.PlayListTracks
-                    .OrderBy(playListTrack => playListTrack.Position)
-                    .Take(CoverTrackCount)
-                    .Select(playListTrack => playListTrack.TrackId)
-                    .ToList(),
-                playList.OwnerUserId,
-                playList.PlayListTracks.Count(playListTrack => playListTrack.Track.LifeCycleStatus == LifeCycleStatus.Active),
-                playList.PlayListTracks
-                    .Where(playListTrack => playListTrack.Track.LifeCycleStatus == LifeCycleStatus.Active)
-                    .Sum(playListTrack => playListTrack.Track.DurationSeconds)));
-    }
-}

backend/Core/Musify.Application/PlayLists/UpdatePlayList.cs

@@ -1,81 +0,0 @@
-using ErrorOr;
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Microsoft.Extensions.Logging;
-using Musify.Application.Configuration;
-using Musify.Application.Contracts;
-using Musify.Application.Events;
-using Musify.Application.Pictures;
-using Musify.Application.PlayLists.Responses;
-using Musify.Application.Services;
-using Musify.Application.Shared;
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.PlayLists
-{
-    public record UpdatePlayListCommand(
-        long UserId,
-        Guid PlayListId,
-        string? NewName,
-        string? NewDescription,
-        Guid? NewPictureIntentId,
-        PlayListVisibility? NewVisibility = null)
-        : ICommand<ErrorOr<PlayListApplicationResponse>>;
-
-    public class UpdatePlayListCommandHandler(
-        IEventBus eventBus,
-        IDatabase database,
-        UploadIntentValidator uploadIntentValidator,
-        ILogger<UpdatePlayListCommandHandler> logger,
-        PlayListConfiguration playListConfiguration)
-        : ICommandHandler<UpdatePlayListCommand, ErrorOr<PlayListApplicationResponse>>
-    {
-        public async ValueTask<ErrorOr<PlayListApplicationResponse>> Handle(UpdatePlayListCommand request, CancellationToken cancellationToken)
-        {
-            var found = await database.PlayLists.FindOwnedAsync(request.PlayListId, request.UserId, cancellationToken);
-            if (found.IsError)
-                return found.Errors;
-
-            var playList = found.Value;
-
-            if (!string.IsNullOrWhiteSpace(request.NewName))
-            {
-                playList.Name = request.NewName.Trim();
-                playList.NormalizedName = TextNormalizer.Normalize(request.NewName);
-            }
-
-            // null means "unchanged"; a blank description clears it.
-            if (request.NewDescription != null)
-                playList.Description = string.IsNullOrWhiteSpace(request.NewDescription) ? null : request.NewDescription.Trim();
-
-            if (request.NewVisibility is { } visibility)
-                playList.Visibility = visibility;
-
-            if (request.NewPictureIntentId is { } intentId)
-            {
-                var prepared = await PictureSourceChange.PrepareAsync(
-                    uploadIntentValidator, intentId, request.UserId, UploadIntentPurpose.PlayListPicture, playListConfiguration, cancellationToken);
-                if (prepared.IsError)
-                    return prepared.Errors;
-
-                var picture = prepared.Value;
-                playList.Pictures = picture.Pictures;
-
-                await eventBus.PublishAsync(
-                    new UpdatePlayListPictureSourceEvent(
-                        playList.Id, picture.Intent.Id, picture.Intent.Bucket, picture.Intent.Key, picture.FinalKey, picture.Sizes),
-                    cancellationToken);
-            }
-
-            await database.SaveChangesAsync(cancellationToken);
-
-            logger.LogInformation("Updated playlist {PlayListId}", playList.Id);
-
-            return await database.PlayLists
-                .AsNoTracking()
-                .Where(p => p.Id == playList.Id)
-                .SelectResponse()
-                .SingleAsync(cancellationToken);
-        }
-    }
-}

backend/Core/Musify.Application/Services/TrackStreamIssuer.cs

@@ -1,36 +0,0 @@
-using Musify.Application.Configuration;
-using Musify.Application.Contracts;
-using Musify.Application.Tracks.Responses;
-
-namespace Musify.Application.Services
-{
-    /// <summary>Builds the stream URL and signed ticket for a processed track. It never touches the database.</summary>
-    public sealed class TrackStreamIssuer(
-        IStreamTicketService ticketService,
-        TrackConfiguration trackConfiguration,
-        StreamGatewayConfiguration streamGatewayConfiguration,
-        PlaybackConfiguration playbackConfiguration)
-    {
-        public TrackStreamResponse Issue(string audioFolderName, long? userId, Guid? listenId)
-        {
-            var folderPath = trackConfiguration.Routes.BuildProcessedAudioPath(audioFolderName);
-            var ticket = ticketService.IssueTicket(userId, $"{folderPath}/", AnonymousFragmentBytes(userId));
-
-            var manifestUrl = string.Join('/',
-                streamGatewayConfiguration.PublicBaseUrl.TrimEnd('/'),
-                "media",
-                folderPath,
-                streamGatewayConfiguration.AudioFileName);
-
-            return new TrackStreamResponse(manifestUrl, ticket.Token, ticket.ExpiresInSeconds, listenId);
-        }
-
-        private long? AnonymousFragmentBytes(long? userId)
-        {
-            if (userId != null || playbackConfiguration.AnonymousFragmentSeconds <= 0)
-                return null;
-
-            return (long)playbackConfiguration.AnonymousFragmentSeconds * playbackConfiguration.EstimatedAudioBytesPerSecond;
-        }
-    }
-}

backend/Core/Musify.Application/Services/UploadIntentIssuer.cs

@@ -1,134 +0,0 @@
-using ErrorOr;
-using Microsoft.EntityFrameworkCore;
-using Microsoft.Extensions.Logging;
-using Musify.Application.Configuration;
-using Musify.Application.Contracts;
-using Musify.Application.Pictures.Responses;
-using Musify.Application.Shared;
-using Musify.Domain.Entities;
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.Services
-{
-    public sealed record UploadRequest(
-        UploadIntentPurpose Purpose,
-        PictureRoutes Routes,
-        string FileType,
-        string ContentType,
-        long? ExpectedSizeBytes);
-
-    public sealed record IssuedUpload(
-        Guid IntentId,
-        string Key,
-        string ObjectName,
-        string ContentType,
-        string UploadUrl);
-
-    /// <summary>Issues pre-signed upload URLs and the upload intents that track them, checking the user quota first.</summary>
-    public sealed class UploadIntentIssuer(
-        IDatabase database,
-        IStorageService storageService,
-        UploadIntentValidator uploadIntentValidator,
-        ApplicationStorageConfiguration storageConfiguration,
-        UploadIntentConfiguration uploadIntentConfiguration,
-        ILogger<UploadIntentIssuer> logger)
-    {
-        public async Task<ErrorOr<IReadOnlyList<IssuedUpload>>> IssueAsync(
-            long userId,
-            IReadOnlyList<UploadRequest> requests,
-            CancellationToken cancellationToken)
-        {
-            var userExists = await database.Users
-                .AsNoTracking()
-                .AnyAsync(user => user.Id == userId, cancellationToken);
-            if (!userExists)
-                return AppErrors.NotFound("User", userId);
-
-            var planned = requests
-                .Select(request =>
-                {
-                    var objectName = $"{Guid.NewGuid()}.{request.FileType.TrimStart('.').ToLowerInvariant()}";
-                    var key = request.Routes.BuildTempPath(uploadIntentConfiguration.TempRootPrefix, userId, objectName);
-                    var size = request.ExpectedSizeBytes ?? DefaultSize(request.Purpose);
-                    return (Request: request, ObjectName: objectName, Key: key, Size: size);
-                })
-                .ToList();
-
-            await using var transaction = await database.BeginTransactionAsync(
-                System.Data.IsolationLevel.Serializable, cancellationToken);
-
-            var quota = await uploadIntentValidator.CheckQuotaAsync(
-                userId, planned.Sum(item => item.Size), planned.Count, cancellationToken);
-            if (quota.IsError)
-                return quota.Errors;
-
-            var expiresIn = TimeSpan.FromSeconds(uploadIntentConfiguration.UploadUrlExpiresInSeconds);
-            var expiresAt = DateTime.UtcNow + expiresIn;
-            var issued = new List<IssuedUpload>(planned.Count);
-
-            foreach (var item in planned)
-            {
-                var uploadUrl = await storageService.GetUploadUrlAsync(
-                    storageConfiguration.Bucket, item.Key, item.Request.ContentType, expiresIn, cancellationToken: cancellationToken);
-
-                var intent = new UploadIntent
-                {
-                    UserId = userId,
-                    Bucket = storageConfiguration.Bucket,
-                    Key = item.Key,
-                    ObjectName = item.ObjectName,
-                    ContentType = item.Request.ContentType,
-                    ExpectedSizeBytes = item.Size,
-                    Purpose = item.Request.Purpose,
-                    ExpiresAt = expiresAt,
-                };
-
-                await database.UploadIntents.AddAsync(intent, cancellationToken);
-                issued.Add(new IssuedUpload(intent.Id, item.Key, item.ObjectName, item.Request.ContentType, uploadUrl));
-            }
-
-            await database.SaveChangesAsync(cancellationToken);
-            await transaction.CommitAsync(cancellationToken);
-
-            logger.LogInformation("Issued {Count} upload intents for user {UserId} ({Purposes})",
-                issued.Count, userId, string.Join('/', planned.Select(item => item.Request.Purpose)));
-
-            return issued;
-        }
-
-        public async Task<ErrorOr<IssuedUpload>> IssueOneAsync(long userId, UploadRequest request, CancellationToken cancellationToken)
-        {
-            var issued = await IssueAsync(userId, [request], cancellationToken);
-            return issued.IsError ? issued.Errors : issued.Value[0];
-        }
-
-        public async Task<ErrorOr<PictureUploadResponse>> IssuePictureAsync(
-            long userId,
-            UploadIntentPurpose purpose,
-            IPictureOwnerConfiguration owner,
-            string fileType,
-            string contentType,
-            long? expectedSizeBytes,
-            CancellationToken cancellationToken)
-        {
-            var issued = await IssueOneAsync(
-                userId, new UploadRequest(purpose, owner.Routes, fileType, contentType, expectedSizeBytes), cancellationToken);
-            if (issued.IsError)
-                return issued.Errors;
-
-            return new PictureUploadResponse(
-                issued.Value.IntentId,
-                storageConfiguration.Bucket,
-                issued.Value.Key,
-                issued.Value.ObjectName,
-                issued.Value.ContentType,
-                uploadIntentConfiguration.UploadUrlExpiresInSeconds,
-                issued.Value.UploadUrl);
-        }
-
-        private long DefaultSize(UploadIntentPurpose purpose) =>
-            purpose == UploadIntentPurpose.TrackAudio
-                ? uploadIntentConfiguration.DefaultExpectedAudioSizeBytes
-                : uploadIntentConfiguration.DefaultExpectedPictureSizeBytes;
-    }
-}

backend/Core/Musify.Application/Services/UploadIntentValidator.cs

@@ -1,78 +0,0 @@
-using ErrorOr;
-using Microsoft.EntityFrameworkCore;
-using Musify.Application.Configuration;
-using Musify.Application.Contracts;
-using Musify.Application.Shared;
-using Musify.Domain.Entities;
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.Services
-{
-    public sealed class UploadIntentValidator(
-        IDatabase database,
-        IStorageService storageService,
-        UploadIntentConfiguration config)
-    {
-        public async Task<ErrorOr<Success>> CheckQuotaAsync(
-            long userId,
-            long requiredBytes,
-            int requiredIntentCount,
-            CancellationToken cancellationToken)
-        {
-            var now = DateTime.UtcNow;
-            var pictureDefault = config.DefaultExpectedPictureSizeBytes;
-            var audioDefault = config.DefaultExpectedAudioSizeBytes;
-
-            var active = await database.UploadIntents
-                .AsNoTracking()
-                .Where(intent => intent.UserId == userId && intent.Status == UploadIntentStatus.Issued && intent.ExpiresAt > now)
-                .GroupBy(_ => 1)
-                .Select(group => new
-                {
-                    Count = group.Count(),
-                    Bytes = group.Sum(intent => intent.ExpectedSizeBytes
-                        ?? (intent.Purpose == UploadIntentPurpose.TrackAudio ? audioDefault : pictureDefault))
-                })
-                .SingleOrDefaultAsync(cancellationToken);
-
-            if ((active?.Count ?? 0) + requiredIntentCount > config.MaxActiveUploadIntentsPerUser)
-                return Error.Validation(description: "Upload intent limit exceeded. Wait for existing uploads to complete or expire.");
-
-            if ((active?.Bytes ?? 0) + requiredBytes > config.MaxActiveUploadBytesPerUser)
-                return Error.Validation(description: "Upload byte quota exceeded. Wait for existing uploads to complete or expire.");
-
-            return Result.Success;
-        }
-
-        public async Task<ErrorOr<UploadIntent>> ValidateAndLoadAsync(
-            Guid intentId,
-            long userId,
-            UploadIntentPurpose purpose,
-            CancellationToken cancellationToken)
-        {
-            var intent = await database.UploadIntents
-                .FirstOrDefaultAsync(i => i.Id == intentId, cancellationToken);
-
-            if (intent == null || intent.UserId != userId)
-                return AppErrors.NotFound("UploadIntent", intentId);
-
-            if (intent.Purpose != purpose)
-                return Error.Validation(description: "Upload intent was issued for a different purpose.");
-
-            if (intent.IsConsumed)
-                return AppErrors.Conflict("UploadIntent.Consumed", "Upload intent has already been consumed.");
-
-            if (intent.IsExpiredAt(DateTime.UtcNow))
-                return Error.Validation(description: "Upload intent has expired.");
-
-            var metadata = await storageService.HeadObjectAsync(intent.Bucket, intent.Key, cancellationToken);
-            if (metadata == null)
-                return Error.NotFound("UploadIntent.ObjectMissing", "Uploaded object not found in storage. Upload the file first.");
-
-            if (metadata.ContentLength > config.MaxUploadBytes)
-                return Error.Validation(description: $"Uploaded file exceeds the maximum allowed size of {config.MaxUploadBytes} bytes.");
-
-            return intent;
-        }
-    }
-}

backend/Core/Musify.Application/Shared/AppErrors.cs

@@ -1,16 +0,0 @@
-using ErrorOr;
-
-namespace Musify.Application.Shared
-{
-    public static class AppErrors
-    {
-        public static Error NotFound(string entity, object id) =>
-            Error.NotFound($"{entity}.NotFound", $"{entity} {id} was not found.");
-
-        public static Error Forbidden(string entity, object id) =>
-            Error.Forbidden($"{entity}.Forbidden", $"You do not have permission to modify {entity} {id}.");
-
-        public static Error Conflict(string code, string description) =>
-            Error.Conflict(code, description);
-    }
-}

backend/Core/Musify.Application/Shared/ImageSize.cs

@@ -1,12 +0,0 @@
-namespace Musify.Application.Shared
-{
-    public record ImageSize(
-        string SavePath,
-        int Width,
-        int Height);
-
-    public record ImageSizes(
-        ImageSize Small,
-        ImageSize Medium,
-        ImageSize Large);
-}

backend/Core/Musify.Application/Shared/OwnershipExtensions.cs

@@ -1,29 +0,0 @@
-using ErrorOr;
-using Microsoft.EntityFrameworkCore;
-using Musify.Domain.Abstractions;
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.Shared
-{
-    public static class OwnershipExtensions
-    {
-        /// <summary>
-        /// Loads an active, tracked entity owned by <paramref name="userId"/>: NotFound when it is missing
-        /// or not active, Forbidden when someone else owns it.
-        /// </summary>
-        public static async Task<ErrorOr<T>> FindOwnedAsync<T>(
-            this DbSet<T> set, Guid id, long userId, CancellationToken cancellationToken)
-            where T : class, IOwnedEntity, IHasLifeCycle
-        {
-            var entity = await set.SingleOrDefaultAsync(
-                e => e.Id == id && e.LifeCycleStatus == LifeCycleStatus.Active, cancellationToken);
-
-            if (entity == null)
-                return AppErrors.NotFound(typeof(T).Name, id);
-
-            return entity.OwnerUserId == userId
-                ? entity
-                : AppErrors.Forbidden(typeof(T).Name, id);
-        }
-    }
-}

backend/Core/Musify.Application/Shared/Pagination.cs

@@ -1,46 +0,0 @@
-using Microsoft.EntityFrameworkCore;
-
-namespace Musify.Application.Shared
-{
-    public record PageRequest(int PageNumber = 1, int PageSize = 20)
-    {
-        public const int MaxPageSize = 100;
-    }
-
-    public record PaginatedResponse<T>(
-        IReadOnlyList<T> Items,
-        int PageNumber,
-        int PageSize,
-        int PageCount,
-        int TotalItemCount,
-        bool HasNextPage,
-        bool HasPreviousPage);
-
-    public static class PaginationExtensions
-    {
-        /// <summary>Counts and pages the same (already filtered, ordered and projected) query.</summary>
-        public static async Task<PaginatedResponse<T>> ToPaginatedAsync<T>(
-            this IQueryable<T> query, PageRequest page, CancellationToken cancellationToken)
-        {
-            var pageNumber = Math.Max(page.PageNumber, 1);
-            var pageSize = Math.Clamp(page.PageSize, 1, PageRequest.MaxPageSize);
-
-            var totalCount = await query.CountAsync(cancellationToken);
-            var items = await query
-                .Skip((pageNumber - 1) * pageSize)
-                .Take(pageSize)
-                .ToListAsync(cancellationToken);
-
-            var pageCount = (int)Math.Ceiling(totalCount / (double)pageSize);
-
-            return new PaginatedResponse<T>(
-                items,
-                pageNumber,
-                pageSize,
-                pageCount,
-                totalCount,
-                HasNextPage: pageNumber < pageCount,
-                HasPreviousPage: pageNumber > 1 && pageCount > 0);
-        }
-    }
-}

backend/Core/Musify.Application/Shared/TextNormalizer.cs

@@ -1,7 +0,0 @@
-namespace Musify.Application.Shared
-{
-    public static class TextNormalizer
-    {
-        public static string Normalize(string value) => value.Trim().ToUpperInvariant();
-    }
-}

backend/Core/Musify.Application/Tracks/CreateTrack.cs

@@ -1,114 +0,0 @@
-using ErrorOr;
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Microsoft.Extensions.Logging;
-using Musify.Application.Configuration;
-using Musify.Application.Contracts;
-using Musify.Application.Events;
-using Musify.Application.Services;
-using Musify.Application.Shared;
-using Musify.Application.Tracks.Responses;
-using Musify.Domain.Entities;
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.Tracks
-{
-    public record CreateTrackCommand(
-        long UserId,
-        string Title,
-        Guid PictureIntentId,
-        Guid AudioIntentId,
-        IReadOnlyCollection<Genre> Tags,
-        bool IsExplicit = false)
-        : ICommand<ErrorOr<TrackApplicationResponse>>;
-
-    public class CreateTrackCommandHandler(
-        IDatabase database,
-        IEventBus eventBus,
-        UploadIntentValidator uploadIntentValidator,
-        ILogger<CreateTrackCommandHandler> logger,
-        TrackConfiguration trackConfiguration)
-        : ICommandHandler<CreateTrackCommand, ErrorOr<TrackApplicationResponse>>
-    {
-        public async ValueTask<ErrorOr<TrackApplicationResponse>> Handle(CreateTrackCommand request, CancellationToken cancellationToken)
-        {
-            var user = await database.Users
-                .SingleOrDefaultAsync(u => u.Id == request.UserId, cancellationToken);
-            if (user == null)
-            {
-                logger.LogWarning("User {UserId} not found", request.UserId);
-                return Error.NotFound(description: $"User {request.UserId} not found");
-            }
-
-            var distinctTags = request.Tags.Distinct().ToList();
-
-            if (request.PictureIntentId == request.AudioIntentId)
-                return Error.Validation(description: "Picture and audio must use different upload intents.");
-
-            var pictureValidation = await uploadIntentValidator.ValidateAndLoadAsync(
-                request.PictureIntentId, request.UserId, UploadIntentPurpose.TrackPicture, cancellationToken);
-            if (pictureValidation.IsError)
-                return pictureValidation.Errors;
-
-            var audioValidation = await uploadIntentValidator.ValidateAndLoadAsync(
-                request.AudioIntentId, request.UserId, UploadIntentPurpose.TrackAudio, cancellationToken);
-            if (audioValidation.IsError)
-                return audioValidation.Errors;
-
-            var pictureIntent = pictureValidation.Value;
-            var audioIntent = audioValidation.Value;
-
-            var finalPictureKey = trackConfiguration.Routes.BuildOriginalPicturePath(request.UserId, pictureIntent.ObjectName);
-            var finalAudioKey = trackConfiguration.Routes.BuildOriginalAudioPath(request.UserId, audioIntent.ObjectName);
-            var audioProcessedFolderKey = trackConfiguration.Routes.BuildProcessedAudioPath(Guid.NewGuid().ToString());
-
-            var trackEntity = new Track
-            {
-                Title = request.Title.Trim(),
-                NormalizedTitle = TextNormalizer.Normalize(request.Title),
-                OwnerUserId = user.Id,
-                Owner = user,
-                IsExplicit = request.IsExplicit,
-                Pictures = new TrackPictures
-                {
-                    OriginalName = pictureIntent.ObjectName,
-                    SmallName = trackConfiguration.Routes.PresetSmallPicture,
-                    MediumName = trackConfiguration.Routes.PresetMediumPicture,
-                    LargeName = trackConfiguration.Routes.PresetLargePicture,
-                    ProcessingStatus = ProcessingStatus.Pending
-                },
-                Audio = new TrackAudio
-                {
-                    OriginalName = audioIntent.ObjectName,
-                    TranscodeStatus = ProcessingStatus.Pending
-                }
-            };
-
-            trackEntity.Tags = distinctTags
-                .Select(tag => new TrackTag { TrackId = trackEntity.Id, Tag = tag })
-                .ToList();
-
-            await database.Tracks.AddAsync(trackEntity, cancellationToken);
-
-
-            var sizes = trackConfiguration.PicturesSizes.ToImageSizes(trackConfiguration.Routes);
-            await eventBus.PublishAsync(
-                new CreateTrackResourcesEvent(
-                    trackEntity.Id,
-                    pictureIntent.Id,
-                    audioIntent.Id,
-                    pictureIntent.Bucket,
-                    pictureIntent.Key,
-                    finalPictureKey,
-                    audioIntent.Key,
-                    finalAudioKey,
-                    audioProcessedFolderKey,
-                    sizes),
-                cancellationToken);
-
-            await database.SaveChangesAsync(cancellationToken);
-
-            return TrackApplicationResponse.FromEntity(trackEntity, listensCount: 0);
-        }
-    }
-}

backend/Core/Musify.Application/Tracks/DeleteStaleUncountedListens.cs

@@ -1,33 +0,0 @@
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Microsoft.Extensions.Logging;
-using Musify.Application.Contracts;
-
-namespace Musify.Application.Tracks
-{
-    public record DeleteStaleUncountedListensCommand : ICommand<int>;
-
-    public class DeleteStaleUncountedListensCommandHandler(
-        IDatabase database,
-        ILogger<DeleteStaleUncountedListensCommandHandler> logger)
-        : ICommandHandler<DeleteStaleUncountedListensCommand, int>
-    {
-        public async ValueTask<int> Handle(DeleteStaleUncountedListensCommand request, CancellationToken cancellationToken)
-        {
-            var cutoff = DateTime.UtcNow.AddDays(-ListeningRules.UncountedRetentionDays);
-
-            var stale = await database.ListeningHistories
-                .Where(l => !l.IsCounted && l.ListenedAt < cutoff)
-                .ToListAsync(cancellationToken);
-
-            if (stale.Count == 0)
-                return 0;
-
-            database.ListeningHistories.RemoveRange(stale);
-            await database.SaveChangesAsync(cancellationToken);
-
-            logger.LogInformation("Deleted {Count} uncounted listens older than {Days} days", stale.Count, ListeningRules.UncountedRetentionDays);
-            return stale.Count;
-        }
-    }
-}

backend/Core/Musify.Application/Tracks/DeleteTrack.cs

@@ -1,42 +0,0 @@
-using ErrorOr;
-using Mediator;
-using Microsoft.Extensions.Logging;
-using Musify.Application.Contracts;
-using Musify.Application.Events;
-using Musify.Application.Shared;
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.Tracks
-{
-    public record DeleteTrackCommand(
-        long UserId,
-        Guid TrackId)
-        : ICommand<ErrorOr<Success>>;
-
-    public class DeleteTrackCommandHandler(
-        IDatabase database,
-        IEventBus eventBus,
-        ILogger<DeleteTrackCommandHandler> logger)
-        : ICommandHandler<DeleteTrackCommand, ErrorOr<Success>>
-    {
-        public async ValueTask<ErrorOr<Success>> Handle(DeleteTrackCommand request, CancellationToken cancellationToken)
-        {
-            var found = await database.Tracks.FindOwnedAsync(request.TrackId, request.UserId, cancellationToken);
-            if (found.IsError)
-                return found.Errors;
-
-            var track = found.Value;
-            if (track.Audio.IsInProgress)
-                return AppErrors.Conflict("Track.Processing", "Track is currently being processed and cannot be deleted.");
-
-            track.LifeCycleStatus = LifeCycleStatus.Removing;
-
-            await eventBus.PublishAsync(new DeleteTrackEvent(track.Id, request.UserId), cancellationToken);
-            await database.SaveChangesAsync(cancellationToken);
-
-            logger.LogInformation("Marked track {TrackId} as removing", request.TrackId);
-
-            return Result.Success;
-        }
-    }
-}

backend/Core/Musify.Application/Tracks/GetLastTrackListenedByUserId.cs

@@ -1,27 +0,0 @@
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Musify.Application.Contracts;
-using Musify.Application.Tracks.Responses;
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.Tracks
-{
-    public record GetLastTrackListenedByUserIdQuery(long UserId) : IQuery<TrackApplicationResponse?>;
-
-    public class GetLastTrackListenedByUserIdQueryHandler(IDatabase database)
-        : IQueryHandler<GetLastTrackListenedByUserIdQuery, TrackApplicationResponse?>
-    {
-        public async ValueTask<TrackApplicationResponse?> Handle(GetLastTrackListenedByUserIdQuery query, CancellationToken cancellationToken)
-        {
-            return await database.ListeningHistories
-                .AsNoTracking()
-                .Include(t => t.Track.Owner)
-                .Include(t => t.Track.Tags)
-                .Where(t => t.UserId == query.UserId && t.IsCounted && t.Track.LifeCycleStatus == LifeCycleStatus.Active)
-                .OrderByDescending(t => t.ListenedAt)
-                .ThenBy(t => t.Id)
-                .Select(t => TrackApplicationResponse.FromEntity(t.Track, t.Track.ListeningHistories.Count(l => l.IsCounted)))
-                .FirstOrDefaultAsync(cancellationToken);
-        }
-    }
-}

backend/Core/Musify.Application/Tracks/GetListeningHistory.cs

@@ -1,40 +0,0 @@
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Musify.Application.Contracts;
-using Musify.Application.Tracks.Responses;
-
-namespace Musify.Application.Tracks
-{
-    public record GetListeningHistoryQuery(long UserId) : IQuery<IReadOnlyList<TrackApplicationResponse>>;
-
-    public class GetListeningHistoryQueryHandler(IDatabase database)
-        : IQueryHandler<GetListeningHistoryQuery, IReadOnlyList<TrackApplicationResponse>>
-    {
-        public const int ListSize = 15;
-
-        public async ValueTask<IReadOnlyList<TrackApplicationResponse>> Handle(GetListeningHistoryQuery query, CancellationToken cancellationToken)
-        {
-            var recentTrackIds = await database.ListeningHistories
-                .AsNoTracking()
-                .Where(l => l.UserId == query.UserId && l.IsCounted)
-                .GroupBy(l => l.TrackId)
-                .OrderByDescending(g => g.Max(l => l.ListenedAt))
-                .ThenBy(g => g.Key)
-                .Select(g => g.Key)
-                .Take(ListSize)
-                .ToListAsync(cancellationToken);
-
-            var tracksById = await database.Tracks
-                .AsNoTracking()
-                .Active()
-                .Where(t => recentTrackIds.Contains(t.Id))
-                .SelectResponse()
-                .ToDictionaryAsync(t => t.Id, cancellationToken);
-
-            return recentTrackIds
-                .Where(id => tracksById.ContainsKey(id))
-                .Select(id => tracksById[id])
-                .ToList();
-        }
-    }
-}

backend/Core/Musify.Application/Tracks/GetTracks.cs

@@ -1,38 +0,0 @@
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Musify.Application.Contracts;
-using Musify.Application.Shared;
-using Musify.Application.Tracks.Responses;
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.Tracks
-{
-    public record GetTracksQuery(string? Name, int PageNumber, int PageSize, Genre? Genre = null)
-        : IQuery<PaginatedResponse<TrackApplicationResponse>>;
-
-    public class GetTracksQueryHandler(IDatabase database)
-        : IQueryHandler<GetTracksQuery, PaginatedResponse<TrackApplicationResponse>>
-    {
-        public async ValueTask<PaginatedResponse<TrackApplicationResponse>> Handle(GetTracksQuery request, CancellationToken cancellationToken)
-        {
-            var tracksQuery = database.Tracks
-                .AsNoTracking()
-                .Active();
-
-            if (!string.IsNullOrWhiteSpace(request.Name))
-            {
-                var normalizedName = TextNormalizer.Normalize(request.Name);
-                tracksQuery = tracksQuery.Where(track => track.NormalizedTitle.Contains(normalizedName));
-            }
-
-            if (request.Genre is { } genre)
-                tracksQuery = tracksQuery.Where(track => track.Tags.Any(tag => tag.Tag == genre));
-
-            return await tracksQuery
-                .OrderByDescending(track => track.CreatedAt)
-                .ThenBy(track => track.Id)
-                .SelectResponse()
-                .ToPaginatedAsync(new PageRequest(request.PageNumber, request.PageSize), cancellationToken);
-        }
-    }
-}

backend/Core/Musify.Application/Tracks/GetTracksByUserId.cs

@@ -1,40 +0,0 @@
-using ErrorOr;
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Musify.Application.Contracts;
-using Musify.Application.Shared;
-using Musify.Application.Tracks.Responses;
-
-namespace Musify.Application.Tracks
-{
-    public record GetTracksByUserIdQuery(
-        long UserId,
-        string? Name,
-        int PageNumber,
-        int PageSize)
-        : IQuery<ErrorOr<PaginatedResponse<TrackApplicationResponse>>>;
-
-    public class GetTracksByUserIdQueryHandler(IDatabase database)
-        : IQueryHandler<GetTracksByUserIdQuery, ErrorOr<PaginatedResponse<TrackApplicationResponse>>>
-    {
-        public async ValueTask<ErrorOr<PaginatedResponse<TrackApplicationResponse>>> Handle(GetTracksByUserIdQuery request, CancellationToken cancellationToken)
-        {
-            var tracksQuery = database.Tracks
-                .AsNoTracking()
-                .Active()
-                .Where(track => track.OwnerUserId == request.UserId);
-
-            if (!string.IsNullOrWhiteSpace(request.Name))
-            {
-                var normalizedName = TextNormalizer.Normalize(request.Name);
-                tracksQuery = tracksQuery.Where(track => track.NormalizedTitle.Contains(normalizedName));
-            }
-
-            return await tracksQuery
-                .OrderByDescending(track => track.CreatedAt)
-                .ThenBy(track => track.Id)
-                .SelectResponse()
-                .ToPaginatedAsync(new PageRequest(request.PageNumber, request.PageSize), cancellationToken);
-        }
-    }
-}

backend/Core/Musify.Application/Tracks/ListeningRules.cs

@@ -1,14 +0,0 @@
-namespace Musify.Application.Tracks
-{
-    public static class ListeningRules
-    {
-        public const double CountedThresholdSeconds = 30;
-        public const double CountedThresholdFraction = 0.5;
-        public const double DurationToleranceSeconds = 2;
-        public const double ClockToleranceSeconds = 5;
-        public const int UncountedRetentionDays = 8;
-
-        public static double CountedThreshold(double durationSeconds) =>
-            Math.Min(CountedThresholdSeconds, durationSeconds * CountedThresholdFraction);
-    }
-}

backend/Core/Musify.Application/Tracks/RecordListeningProgress.cs

@@ -1,42 +0,0 @@
-using ErrorOr;
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Musify.Application.Contracts;
-using Musify.Application.Shared;
-
-namespace Musify.Application.Tracks
-{
-    public record RecordListeningProgressCommand(
-        long UserId,
-        Guid ListenId,
-        double PlayedSeconds)
-        : ICommand<ErrorOr<Success>>;
-
-    public class RecordListeningProgressCommandHandler(IDatabase database)
-        : ICommandHandler<RecordListeningProgressCommand, ErrorOr<Success>>
-    {
-        public async ValueTask<ErrorOr<Success>> Handle(RecordListeningProgressCommand request, CancellationToken cancellationToken)
-        {
-            var listen = await database.ListeningHistories
-                .Include(l => l.Track)
-                .SingleOrDefaultAsync(l => l.Id == request.ListenId && l.UserId == request.UserId, cancellationToken);
-
-            if (listen == null)
-                return AppErrors.NotFound("Listen", request.ListenId);
-
-            var now = DateTime.UtcNow;
-            var durationCap = listen.Track.DurationSeconds + ListeningRules.DurationToleranceSeconds;
-            var clockCap = (now - listen.ListenedAt).TotalSeconds + ListeningRules.ClockToleranceSeconds;
-            var accepted = Math.Min(request.PlayedSeconds, Math.Min(durationCap, clockCap));
-
-            listen.PlayedSeconds = Math.Max(listen.PlayedSeconds ?? 0, accepted);
-            listen.LastProgressAt = now;
-            listen.IsCounted = listen.IsCounted
-                || listen.PlayedSeconds >= ListeningRules.CountedThreshold(listen.Track.DurationSeconds);
-
-            await database.SaveChangesAsync(cancellationToken);
-
-            return Result.Success;
-        }
-    }
-}

backend/Core/Musify.Application/Tracks/RequestTrackUploadUrls.cs

@@ -1,58 +0,0 @@
-using ErrorOr;
-using Mediator;
-using Musify.Application.Configuration;
-using Musify.Application.Services;
-using Musify.Application.Tracks.Responses;
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.Tracks
-{
-    public record RequestTrackUploadUrlsCommand(
-        long UserId,
-        string PictureFileType,
-        string PictureContentType,
-        string AudioFileType,
-        string AudioContentType,
-        long? ExpectedPictureSizeBytes = null,
-        long? ExpectedAudioSizeBytes = null)
-        : ICommand<ErrorOr<TrackUploadUrlsResponse>>;
-
-    public class RequestTrackUploadUrlsCommandHandler(
-        UploadIntentIssuer issuer,
-        ApplicationStorageConfiguration storageConfiguration,
-        TrackConfiguration trackConfiguration,
-        UploadIntentConfiguration uploadIntentConfiguration)
-        : ICommandHandler<RequestTrackUploadUrlsCommand, ErrorOr<TrackUploadUrlsResponse>>
-    {
-        public async ValueTask<ErrorOr<TrackUploadUrlsResponse>> Handle(RequestTrackUploadUrlsCommand request, CancellationToken cancellationToken)
-        {
-            var routes = trackConfiguration.Routes;
-            var issued = await issuer.IssueAsync(
-                request.UserId,
-                [
-                    new UploadRequest(UploadIntentPurpose.TrackPicture, routes, request.PictureFileType, request.PictureContentType, request.ExpectedPictureSizeBytes),
-                    new UploadRequest(UploadIntentPurpose.TrackAudio, routes, request.AudioFileType, request.AudioContentType, request.ExpectedAudioSizeBytes)
-                ],
-                cancellationToken);
-            if (issued.IsError)
-                return issued.Errors;
-
-            var picture = issued.Value[0];
-            var audio = issued.Value[1];
-
-            return new TrackUploadUrlsResponse(
-                picture.IntentId,
-                audio.IntentId,
-                storageConfiguration.Bucket,
-                picture.Key,
-                picture.ObjectName,
-                picture.ContentType,
-                picture.UploadUrl,
-                audio.Key,
-                audio.ObjectName,
-                audio.ContentType,
-                audio.UploadUrl,
-                uploadIntentConfiguration.UploadUrlExpiresInSeconds);
-        }
-    }
-}

backend/Core/Musify.Application/Tracks/Responses/TrackApplicationResponse.cs

@@ -1,33 +0,0 @@
-using Musify.Domain.Entities;
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.Tracks.Responses
-{
-    public record TrackApplicationResponse(
-        Guid Id,
-        string Title,
-        string? Artist,
-        ProcessingStatus AudioStatus,
-        double Duration,
-        int ListensCount,
-        DateTime CreatedAt,
-        DateTime UpdatedAt,
-        long OwnerUserId,
-        IReadOnlyCollection<Genre> Tags,
-        bool IsExplicit)
-    {
-        public static TrackApplicationResponse FromEntity(Track track, int listensCount) =>
-            new(
-                track.Id,
-                track.Title,
-                track.Owner.Name,
-                track.Audio.TranscodeStatus,
-                track.DurationSeconds,
-                listensCount,
-                track.CreatedAt,
-                track.UpdatedAt,
-                track.OwnerUserId,
-                track.Tags.Select(tag => tag.Tag).ToList(),
-                track.IsExplicit);
-    }
-}

backend/Core/Musify.Application/Tracks/Responses/TrackProjections.cs

@@ -1,25 +0,0 @@
-using Musify.Domain.Entities;
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.Tracks.Responses
-{
-    public static class TrackProjections
-    {
-        public static IQueryable<Track> Active(this IQueryable<Track> query) =>
-            query.Where(track => track.LifeCycleStatus == LifeCycleStatus.Active);
-
-        public static IQueryable<TrackApplicationResponse> SelectResponse(this IQueryable<Track> query) =>
-            query.Select(track => new TrackApplicationResponse(
-                track.Id,
-                track.Title,
-                track.Owner.Name,
-                track.Audio.TranscodeStatus,
-                track.DurationSeconds,
-                track.ListeningHistories.Count(listen => listen.IsCounted),
-                track.CreatedAt,
-                track.UpdatedAt,
-                track.OwnerUserId,
-                track.Tags.Select(tag => tag.Tag).ToList(),
-                track.IsExplicit));
-    }
-}

backend/Core/Musify.Application/Tracks/StartListening.cs

@@ -1,57 +0,0 @@
-using System.Globalization;
-using ErrorOr;
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Microsoft.Extensions.Logging;
-using Musify.Application.Configuration;
-using Musify.Application.Contracts;
-using Musify.Application.Services;
-using Musify.Application.Shared;
-using Musify.Application.Tracks.Responses;
-using Musify.Domain.Entities;
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.Tracks
-{
-    /// <summary>Starts a listen: records it for signed-in users and issues the stream ticket.</summary>
-    public record StartListeningCommand(Guid TrackId, long? UserId)
-        : ICommand<ErrorOr<TrackStreamResponse>>;
-
-    public class StartListeningCommandHandler(
-        IDatabase database,
-        TrackStreamIssuer streamIssuer,
-        PlaybackConfiguration playbackConfiguration,
-        ILogger<StartListeningCommandHandler> logger)
-        : ICommandHandler<StartListeningCommand, ErrorOr<TrackStreamResponse>>
-    {
-        public async ValueTask<ErrorOr<TrackStreamResponse>> Handle(StartListeningCommand request, CancellationToken cancellationToken)
-        {
-            if (request.UserId == null && !playbackConfiguration.AllowAnonymousListening)
-                return Error.Unauthorized(description: "Sign in to stream music, or ask an administrator to enable anonymous listening.");
-
-            var track = await database.Tracks.AsNoTracking()
-                .Where(t => t.Id == request.TrackId && t.LifeCycleStatus == LifeCycleStatus.Active)
-                .Select(t => new { t.Id, t.Audio })
-                .SingleOrDefaultAsync(cancellationToken);
-
-            if (track == null)
-                return AppErrors.NotFound("Track", request.TrackId);
-
-            if (!track.Audio.IsProcessed)
-                return AppErrors.Conflict("Track.AudioNotReady", "Track audio is not available for streaming yet.");
-
-            Guid? listenId = null;
-            if (request.UserId is { } userId)
-            {
-                var listen = new ListeningHistory { UserId = userId, TrackId = track.Id };
-                await database.ListeningHistories.AddAsync(listen, cancellationToken);
-                await database.SaveChangesAsync(cancellationToken);
-                listenId = listen.Id;
-            }
-
-            logger.LogInformation("Issued stream ticket for track {TrackId} to user {UserId}", request.TrackId, request.UserId?.ToString(CultureInfo.InvariantCulture) ?? "(anonymous)");
-
-            return streamIssuer.Issue(track.Audio.FolderName, request.UserId, listenId);
-        }
-    }
-}

backend/Core/Musify.Application/UploadIntents/DeleteStaleTempUploads.cs

@@ -1,39 +0,0 @@
-using Mediator;
-using Microsoft.Extensions.Logging;
-using Musify.Application.Configuration;
-using Musify.Application.Contracts;
-
-namespace Musify.Application.UploadIntents
-{
-    /// <summary>Deletes temporary upload objects that nobody claimed within the retention window.</summary>
-    public record DeleteStaleTempUploadsCommand : ICommand<int>;
-
-    public class DeleteStaleTempUploadsCommandHandler(
-        IStorageService storageService,
-        ApplicationStorageConfiguration storageConfiguration,
-        UploadIntentConfiguration uploadIntentConfiguration,
-        ILogger<DeleteStaleTempUploadsCommandHandler> logger)
-        : ICommandHandler<DeleteStaleTempUploadsCommand, int>
-    {
-        public async ValueTask<int> Handle(DeleteStaleTempUploadsCommand request, CancellationToken cancellationToken)
-        {
-            var cutOff = DateTime.UtcNow.AddDays(-uploadIntentConfiguration.TempUploadsRetentionDays);
-            var deleted = 0;
-
-            await foreach (var (key, lastModified) in storageService.ListObjectsAsync(
-                storageConfiguration.Bucket, uploadIntentConfiguration.TempRootPrefix, cancellationToken))
-            {
-                if (lastModified >= cutOff)
-                    continue;
-
-                await storageService.RemoveFileAsync(storageConfiguration.Bucket, key, cancellationToken);
-                deleted++;
-            }
-
-            if (deleted > 0)
-                logger.LogInformation("Deleted {Deleted} orphaned temp uploads", deleted);
-
-            return deleted;
-        }
-    }
-}

backend/Core/Musify.Application/UploadIntents/ExpireUploadIntents.cs

@@ -1,47 +0,0 @@
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Microsoft.Extensions.Logging;
-using Musify.Application.Configuration;
-using Musify.Application.Contracts;
-using Musify.Domain.ValueObjects;
-
-namespace Musify.Application.UploadIntents
-{
-    /// <summary>Marks overdue upload intents as expired and deletes the ones expired for longer than the retention window.</summary>
-    public record ExpireUploadIntentsCommand : ICommand<int>;
-
-    public class ExpireUploadIntentsCommandHandler(
-        IDatabase database,
-        UploadIntentConfiguration uploadIntentConfiguration,
-        ILogger<ExpireUploadIntentsCommandHandler> logger)
-        : ICommandHandler<ExpireUploadIntentsCommand, int>
-    {
-        public async ValueTask<int> Handle(ExpireUploadIntentsCommand request, CancellationToken cancellationToken)
-        {
-            var now = DateTime.UtcNow;
-
-            var expiredIntents = await database.UploadIntents
-                .Where(intent => intent.Status == UploadIntentStatus.Issued && intent.ExpiresAt < now)
-                .ToListAsync(cancellationToken);
-
-            foreach (var intent in expiredIntents)
-                intent.Status = UploadIntentStatus.Expired;
-
-            var retentionCutoff = now.AddDays(-uploadIntentConfiguration.ExpiredIntentsRetentionDays);
-            var oldExpiredIntents = await database.UploadIntents
-                .Where(intent => intent.Status == UploadIntentStatus.Expired && intent.ExpiresAt < retentionCutoff)
-                .ToListAsync(cancellationToken);
-
-            database.UploadIntents.RemoveRange(oldExpiredIntents);
-
-            if (expiredIntents.Count == 0 && oldExpiredIntents.Count == 0)
-                return 0;
-
-            await database.SaveChangesAsync(cancellationToken);
-            logger.LogInformation("Marked {Expired} upload intents as expired and deleted {Deleted} old ones",
-                expiredIntents.Count, oldExpiredIntents.Count);
-
-            return expiredIntents.Count + oldExpiredIntents.Count;
-        }
-    }
-}

backend/Core/Musify.Application/Users/FollowUser.cs

@@ -1,52 +0,0 @@
-using ErrorOr;
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Microsoft.Extensions.Logging;
-using Musify.Application.Contracts;
-using Musify.Application.Shared;
-using Musify.Domain.Entities;
-
-namespace Musify.Application.Users
-{
-    public record FollowUserCommand(long FollowerId, long FollowedId) : ICommand<ErrorOr<Success>>;
-
-    public class FollowUserCommandHandler(
-        IDatabase database,
-        ILogger<FollowUserCommandHandler> logger)
-        : ICommandHandler<FollowUserCommand, ErrorOr<Success>>
-    {
-        public async ValueTask<ErrorOr<Success>> Handle(FollowUserCommand request, CancellationToken cancellationToken)
-        {
-            if (request.FollowerId == request.FollowedId)
-                return Error.Validation(description: "A user cannot follow themselves.");
-
-            var followedExists = await database.Users
-                .AsNoTracking()
-                .AnyAsync(u => u.Id == request.FollowedId, cancellationToken);
-            if (!followedExists)
-                return AppErrors.NotFound("User", request.FollowedId);
-
-            var alreadyFollowing = await database.UserFollows
-                .AsNoTracking()
-                .AnyAsync(f => f.FollowerId == request.FollowerId && f.FollowedId == request.FollowedId, cancellationToken);
-            if (alreadyFollowing)
-                return Result.Success;
-
-            await database.UserFollows.AddAsync(new UserFollow
-            {
-                FollowerId = request.FollowerId,
-                FollowedId = request.FollowedId
-            }, cancellationToken);
-
-            // A concurrent double click can hit the unique index; already following is a successful no-op.
-            var saved = await database.TrySaveChangesAsync(
-                AppErrors.Conflict("UserFollow.Duplicate", "Already following this user."), cancellationToken);
-            if (saved.IsError)
-                return Result.Success;
-
-            logger.LogInformation("User {FollowerId} followed user {FollowedId}", request.FollowerId, request.FollowedId);
-
-            return Result.Success;
-        }
-    }
-}

backend/Core/Musify.Application/Users/FollowVisibility.cs

@@ -1,30 +0,0 @@
-using Microsoft.EntityFrameworkCore;
-using Musify.Application.Contracts;
-
-namespace Musify.Application.Users
-{
-    public static class FollowVisibility
-    {
-        public static async Task<bool> CanViewFollowersAsync(
-            IDatabase database,
-            long? viewerId,
-            long userId,
-            CancellationToken cancellationToken)
-        {
-            if (viewerId is not { } viewer)
-                return false;
-
-            if (viewer == userId)
-                return true;
-
-            var mutualRows = await database.UserFollows
-                .AsNoTracking()
-                .CountAsync(f =>
-                    (f.FollowerId == viewer && f.FollowedId == userId) ||
-                    (f.FollowerId == userId && f.FollowedId == viewer),
-                    cancellationToken);
-
-            return mutualRows == 2;
-        }
-    }
-}

backend/Core/Musify.Application/Users/GetListeningStats.cs

@@ -1,53 +0,0 @@
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Musify.Application.Contracts;
-using Musify.Application.Users.Responses;
-
-namespace Musify.Application.Users
-{
-    public record GetListeningStatsQuery(long UserId) : IQuery<ListeningStatsResponse>;
-
-    public class GetListeningStatsQueryHandler(IDatabase database)
-        : IQueryHandler<GetListeningStatsQuery, ListeningStatsResponse>
-    {
-        public async ValueTask<ListeningStatsResponse> Handle(GetListeningStatsQuery request, CancellationToken cancellationToken)
-        {
-            var weekAgo = DateTime.UtcNow.AddDays(-7);
-
-            var thisWeekHistory = database.ListeningHistories
-                .AsNoTracking()
-                .Where(l => l.UserId == request.UserId && l.ListenedAt >= weekAgo);
-
-            var tracksThisWeek = await thisWeekHistory
-                .Where(l => l.IsCounted)
-                .Select(l => l.TrackId)
-                .Distinct()
-                .CountAsync(cancellationToken);
-
-            var secondsThisWeek = await thisWeekHistory
-                .Join(database.Tracks.AsNoTracking(), l => l.TrackId, t => t.Id, (l, t) => l.PlayedSeconds ?? (l.IsCounted ? t.DurationSeconds : 0))
-                .SumAsync(cancellationToken);
-
-            var listenedDates = await database.ListeningHistories
-                .AsNoTracking()
-                .Where(l => l.UserId == request.UserId && l.IsCounted)
-                .Select(l => l.ListenedAt.Date)
-                .Distinct()
-                .ToListAsync(cancellationToken);
-
-            var listenedDateSet = listenedDates.ToHashSet();
-            var streakDays = 0;
-            var day = DateTime.UtcNow.Date;
-            if (!listenedDateSet.Contains(day))
-                day = day.AddDays(-1);
-
-            while (listenedDateSet.Contains(day))
-            {
-                streakDays++;
-                day = day.AddDays(-1);
-            }
-
-            return new ListeningStatsResponse(tracksThisWeek, (int)Math.Round(secondsThisWeek), streakDays);
-        }
-    }
-}

backend/Core/Musify.Application/Users/GetUserFollowers.cs

@@ -1,41 +0,0 @@
-using ErrorOr;
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Musify.Application.Contracts;
-using Musify.Application.Shared;
-using Musify.Application.Users.Responses;
-
-namespace Musify.Application.Users
-{
-    public record GetUserFollowersQuery(long? ViewerId, long UserId, int PageNumber, int PageSize)
-        : IQuery<ErrorOr<PaginatedResponse<UserSummaryResponse>>>;
-
-    public class GetUserFollowersQueryHandler(IDatabase database)
-        : IQueryHandler<GetUserFollowersQuery, ErrorOr<PaginatedResponse<UserSummaryResponse>>>
-    {
-        public async ValueTask<ErrorOr<PaginatedResponse<UserSummaryResponse>>> Handle(GetUserFollowersQuery request, CancellationToken cancellationToken)
-        {
-            if (!await database.Users.AnyAsync(u => u.Id == request.UserId, cancellationToken))
-                return AppErrors.NotFound("User", request.UserId);
-
-            if (!await FollowVisibility.CanViewFollowersAsync(database, request.ViewerId, request.UserId, cancellationToken))
-                return AppErrors.Forbidden("User", request.UserId);
-
-            var viewerId = request.ViewerId;
-
-            return await database.UserFollows
-                .AsNoTracking()
-                .Where(f => f.FollowedId == request.UserId)
-                .OrderByDescending(f => f.CreatedAt)
-                .ThenBy(f => f.Id)
-                .Select(f => new UserSummaryResponse(
-                    f.Follower.Id,
-                    f.Follower.Name,
-                    f.Follower.FirstName,
-                    f.Follower.SecondName,
-                    f.Follower.ProfilePictureUrl,
-                    viewerId != null && database.UserFollows.Any(v => v.FollowerId == viewerId && v.FollowedId == f.FollowerId)))
-                .ToPaginatedAsync(new PageRequest(request.PageNumber, request.PageSize), cancellationToken);
-        }
-    }
-}

backend/Core/Musify.Application/Users/GetUserFollowing.cs

@@ -1,38 +0,0 @@
-using ErrorOr;
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Musify.Application.Contracts;
-using Musify.Application.Shared;
-using Musify.Application.Users.Responses;
-
-namespace Musify.Application.Users
-{
-    public record GetUserFollowingQuery(long? ViewerId, long UserId, int PageNumber, int PageSize)
-        : IQuery<ErrorOr<PaginatedResponse<UserSummaryResponse>>>;
-
-    public class GetUserFollowingQueryHandler(IDatabase database)
-        : IQueryHandler<GetUserFollowingQuery, ErrorOr<PaginatedResponse<UserSummaryResponse>>>
-    {
-        public async ValueTask<ErrorOr<PaginatedResponse<UserSummaryResponse>>> Handle(GetUserFollowingQuery request, CancellationToken cancellationToken)
-        {
-            if (!await database.Users.AnyAsync(u => u.Id == request.UserId, cancellationToken))
-                return AppErrors.NotFound("User", request.UserId);
-
-            var viewerId = request.ViewerId;
-
-            return await database.UserFollows
-                .AsNoTracking()
-                .Where(f => f.FollowerId == request.UserId)
-                .OrderByDescending(f => f.CreatedAt)
-                .ThenBy(f => f.Id)
-                .Select(f => new UserSummaryResponse(
-                    f.Followed.Id,
-                    f.Followed.Name,
-                    f.Followed.FirstName,
-                    f.Followed.SecondName,
-                    f.Followed.ProfilePictureUrl,
-                    viewerId != null && database.UserFollows.Any(v => v.FollowerId == viewerId && v.FollowedId == f.FollowedId)))
-                .ToPaginatedAsync(new PageRequest(request.PageNumber, request.PageSize), cancellationToken);
-        }
-    }
-}

backend/Core/Musify.Application/Users/GetUserProfile.cs

@@ -1,63 +0,0 @@
-using ErrorOr;
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Musify.Application.Contracts;
-using Musify.Application.Shared;
-using Musify.Application.Users.Responses;
-
-namespace Musify.Application.Users
-{
-    public record GetUserProfileQuery(long UserId, long? ViewerId = null) : IQuery<ErrorOr<UserProfileResponse>>;
-
-    public class GetUserProfileQueryHandler(IDatabase database)
-        : IQueryHandler<GetUserProfileQuery, ErrorOr<UserProfileResponse>>
-    {
-        public async ValueTask<ErrorOr<UserProfileResponse>> Handle(GetUserProfileQuery request, CancellationToken cancellationToken)
-        {
-            var user = await database.Users
-                .AsNoTracking()
-                .Where(u => u.Id == request.UserId)
-                .Select(u => new
-                {
-                    u.Id,
-                    u.Name,
-                    u.FirstName,
-                    u.SecondName,
-                    u.ProfilePictureUrl,
-                    u.CreatedAt
-                })
-                .SingleOrDefaultAsync(cancellationToken);
-
-            if (user == null)
-                return AppErrors.NotFound("User", request.UserId);
-
-            var followersCount = await database.UserFollows
-                .AsNoTracking()
-                .CountAsync(f => f.FollowedId == request.UserId, cancellationToken);
-
-            var followingCount = await database.UserFollows
-                .AsNoTracking()
-                .CountAsync(f => f.FollowerId == request.UserId, cancellationToken);
-
-            var isFollowing = request.ViewerId is { } viewerId && viewerId != request.UserId &&
-                await database.UserFollows
-                    .AsNoTracking()
-                    .AnyAsync(f => f.FollowerId == viewerId && f.FollowedId == request.UserId, cancellationToken);
-
-            var canViewFollowers = await FollowVisibility.CanViewFollowersAsync(
-                database, request.ViewerId, request.UserId, cancellationToken);
-
-            return new UserProfileResponse(
-                user.Id,
-                user.Name,
-                user.FirstName,
-                user.SecondName,
-                user.ProfilePictureUrl,
-                user.CreatedAt,
-                followersCount,
-                followingCount,
-                isFollowing,
-                canViewFollowers);
-        }
-    }
-}

backend/Core/Musify.Application/Users/GetUsers.cs

@@ -1,41 +0,0 @@
-using Mediator;
-using Microsoft.EntityFrameworkCore;
-using Musify.Application.Contracts;
-using Musify.Application.Shared;
-using Musify.Application.Users.Responses;
-
-namespace Musify.Application.Users
-{
-    public record GetUsersQuery(int PageNumber, int PageSize, string? UsernameSearch, long? ViewerId = null)
-        : IQuery<PaginatedResponse<UserSummaryResponse>>;
-
-    public class GetUsersQueryHandler(IDatabase database)
-        : IQueryHandler<GetUsersQuery, PaginatedResponse<UserSummaryResponse>>
-    {
-        public async ValueTask<PaginatedResponse<UserSummaryResponse>> Handle(GetUsersQuery request, CancellationToken cancellationToken)
-        {
-            var usersQuery = database.Users
-                .AsNoTracking();
-
-            if (!string.IsNullOrWhiteSpace(request.UsernameSearch))
-            {
-                var normalizedUsername = TextNormalizer.Normalize(request.UsernameSearch);
-                usersQuery = usersQuery.Where(user => user.NormalizedName.Contains(normalizedUsername));
-            }
-
-            var viewerId = request.ViewerId;
-
-            return await usersQuery
-                .OrderBy(user => user.Name)
-                .ThenBy(user => user.Id)
-                .Select(user => new UserSummaryResponse(
-                    user.Id,
-                    user.Name,
-                    user.FirstName,
-                    user.SecondName,
-                    user.ProfilePictureUrl,
-                    viewerId != null && database.UserFollows.Any(f => f.FollowerId == viewerId && f.FollowedId == user.Id)))
-                .ToPaginatedAsync(new PageRequest(request.PageNumber, request.PageSize), cancellationToken);
-        }
-    }
-}