Musify/backend/Hosts/Musify.Api/Endpoints/AlbumEndpoints.cs

using Mediator;
using Musify.Api.Authentication;
using Musify.Api.DataTransferObjects;
using Musify.Api.DataTransferObjects.Albums;
using Musify.Api.Extensions;
using Musify.Api.Filters;
using Musify.Api.Models;
using Musify.Application.Albums;
using Musify.Application.Albums.Responses;
using Musify.Application.Contracts;
using Musify.Application.Pictures;
using Musify.Application.Pictures.Responses;
using Musify.Application.Shared;
using Musify.Application.Tracks.Responses;

namespace Musify.Api.Endpoints
{
    public static class AlbumEndpoints
    {
        private const int MaxRecentAlbumsLimit = 50;

        public static IEndpointRouteBuilder MapAlbumEndpoints(this IEndpointRouteBuilder app)
        {
            var group = app.MapGroup("/albums")
                .WithTags("Albums");

            group.MapGet("/", GetAlbums)
                .AddEndpointFilter<ValidationFilter<PageQuery>>()
                .WithName("GetAlbums")
                .WithSummary("Get paginated albums, optionally filtered by title")
                .Produces<PaginatedResponse<AlbumApplicationResponse>>();

            group.MapGet("/{id:guid}", GetAlbumById)
                .WithName("GetAlbumById")
                .WithSummary("Get an album by id")
                .Produces<AlbumApplicationResponse>()
                .Produces(StatusCodes.Status404NotFound);

            group.MapGet("/users/{userId:long}", GetAlbumsByUserId)
                .AddEndpointFilter<ValidationFilter<PageQuery>>()
                .WithName("GetAlbumsByUserId")
                .WithSummary("Get paginated albums for a user")
                .Produces<PaginatedResponse<AlbumApplicationResponse>>()
                .Produces(StatusCodes.Status404NotFound);

            group.MapGet("/recent", GetRecentlyListenedAlbums)
                .WithName("GetRecentlyListenedAlbums")
                .WithSummary("Get the albums the current user listened to most recently")
                .RequireAuthorization()
                .Produces<IReadOnlyList<AlbumApplicationResponse>>()
                .Produces(StatusCodes.Status401Unauthorized);

            group.MapGet("/{id:guid}/tracks", GetAlbumTracks)
                .AddEndpointFilter<ValidationFilter<PageQuery>>()
                .WithName("GetAlbumTracks")
                .WithSummary("Get the tracks of an album ordered by track number")
                .Produces<PaginatedResponse<TrackApplicationResponse>>()
                .Produces(StatusCodes.Status404NotFound);

            group.MapGet("/{id:guid}/cover", GetAlbumCover)
                .WithName("GetAlbumCover")
                .WithSummary("Get an album cover image")
                .Produces(StatusCodes.Status200OK)
                .Produces(StatusCodes.Status404NotFound);

            group.MapPost("/upload-picture", RequestAlbumPictureUpload)
                .WithName("RequestAlbumPictureUpload")
                .WithSummary("Request a pre-signed URL to upload an album picture")
                .AddEndpointFilter<ValidationFilter<PictureUploadRequest>>()
                .RequireAuthorization()
                .Produces<PictureUploadResponse>()
                .ProducesValidationProblem()
                .Produces(StatusCodes.Status401Unauthorized)
                .Produces(StatusCodes.Status404NotFound);

            group.MapPost("/", CreateAlbum)
                .WithName("CreateAlbum")
                .WithSummary("Create a new album")
                .AddEndpointFilter<ValidationFilter<CreateAlbumRequest>>()
                .RequireAuthorization()
                .Produces<AlbumApplicationResponse>(StatusCodes.Status201Created)
                .ProducesValidationProblem()
                .Produces(StatusCodes.Status401Unauthorized)
                .Produces(StatusCodes.Status404NotFound);

            group.MapPut("/{id:guid}", UpdateAlbum)
                .WithName("UpdateAlbum")
                .WithSummary("Update an album")
                .AddEndpointFilter<ValidationFilter<UpdateAlbumRequest>>()
                .RequireAuthorization()
                .Produces<AlbumApplicationResponse>()
                .ProducesValidationProblem()
                .Produces(StatusCodes.Status401Unauthorized)
                .Produces(StatusCodes.Status403Forbidden)
                .Produces(StatusCodes.Status404NotFound);

            group.MapDelete("/{id:guid}", DeleteAlbum)
                .WithName("DeleteAlbum")
                .WithSummary("Delete an album")
                .RequireAuthorization()
                .Produces(StatusCodes.Status204NoContent)
                .Produces(StatusCodes.Status401Unauthorized)
                .Produces(StatusCodes.Status403Forbidden)
                .Produces(StatusCodes.Status404NotFound);

            group.MapPost("/{id:guid}/tracks", AddAlbumTracks)
                .WithName("AddAlbumTracks")
                .WithSummary("Add your uploaded tracks to an album, skipping the ones it already has")
                .AddEndpointFilter<ValidationFilter<AddTracksRequest>>()
                .RequireAuthorization()
                .Produces(StatusCodes.Status204NoContent)
                .ProducesValidationProblem()
                .Produces(StatusCodes.Status401Unauthorized)
                .Produces(StatusCodes.Status403Forbidden)
                .Produces(StatusCodes.Status404NotFound)
                .Produces(StatusCodes.Status409Conflict);

            group.MapDelete("/{id:guid}/tracks/{trackId:guid}", RemoveTrackFromAlbum)
                .WithName("RemoveTrackFromAlbum")
                .WithSummary("Remove a track from an album")
                .RequireAuthorization()
                .Produces(StatusCodes.Status204NoContent)
                .Produces(StatusCodes.Status401Unauthorized)
                .Produces(StatusCodes.Status403Forbidden)
                .Produces(StatusCodes.Status404NotFound);

            return app;
        }

        private static async Task<IResult> GetAlbums(
            IMediator mediator,
            string? title,
            [AsParameters] PageQuery page,
            CancellationToken cancellationToken)
        {
            var result = await mediator.Send(new GetAlbumsQuery(title, page.PageNumber, page.PageSize), cancellationToken);
            return Results.Ok(result);
        }

        private static async Task<IResult> GetAlbumById(
            IMediator mediator,
            Guid id,
            CancellationToken cancellationToken)
        {
            var result = await mediator.Send(new GetAlbumByIdQuery(id), cancellationToken);
            return result.ToHttpResult();
        }

        private static async Task<IResult> GetAlbumsByUserId(
            IMediator mediator,
            long userId,
            [AsParameters] PageQuery page,
            CancellationToken cancellationToken)
        {
            var result = await mediator.Send(new GetAlbumsByUserIdQuery(userId, page.PageNumber, page.PageSize), cancellationToken);
            return result.ToHttpResult();
        }

        private static async Task<IResult> GetRecentlyListenedAlbums(
            IMediator mediator,
            CurrentUser currentUser,
            CancellationToken cancellationToken,
            int limit = 12)
        {
            if (limit is < 1 or > MaxRecentAlbumsLimit)
            {
                return Results.ValidationProblem(new Dictionary<string, string[]>
                {
                    [nameof(limit)] = [$"'{nameof(limit)}' must be between 1 and {MaxRecentAlbumsLimit}."]
                });
            }

            var result = await mediator.Send(new GetRecentlyListenedAlbumsQuery(currentUser.RequiredId, limit), cancellationToken);
            return Results.Ok(result);
        }

        private static async Task<IResult> GetAlbumTracks(
            IMediator mediator,
            Guid id,
            [AsParameters] PageQuery page,
            CancellationToken cancellationToken)
        {
            var result = await mediator.Send(new GetAlbumTracksQuery(id, page.PageNumber, page.PageSize), cancellationToken);
            return result.ToHttpResult();
        }

        private static Task<IResult> GetAlbumCover(
            IMediator mediator,
            IStorageService storageService,
            HttpResponse response,
            Guid id,
            CancellationToken cancellationToken,
            string size = "medium")
        {
            return CoverEndpoint.Stream(mediator, storageService, response, CoverOwner.Album, id, size, cancellationToken);
        }

        private static async Task<IResult> RequestAlbumPictureUpload(
            IMediator mediator,
            CurrentUser currentUser,
            PictureUploadRequest request,
            CancellationToken cancellationToken)
        {
            var result = await mediator.Send(
                new RequestAlbumPictureUploadCommand(currentUser.RequiredId, request.FileType, request.ContentType, request.ExpectedSizeBytes),
                cancellationToken);

            return result.ToHttpResult();
        }

        private static async Task<IResult> CreateAlbum(
            IMediator mediator,
            CurrentUser currentUser,
            CreateAlbumRequest request,
            CancellationToken cancellationToken)
        {
            var result = await mediator.Send(
                new CreateAlbumCommand(currentUser.RequiredId, request.Title, request.Description, request.ReleaseYear, request.PictureIntentId),
                cancellationToken);

            return result.ToCreatedResult(album => $"/albums/{album.Id}");
        }

        private static async Task<IResult> UpdateAlbum(
            IMediator mediator,
            CurrentUser currentUser,
            Guid id,
            UpdateAlbumRequest request,
            CancellationToken cancellationToken)
        {
            var result = await mediator.Send(
                new UpdateAlbumCommand(currentUser.RequiredId, id, request.Title, request.Description, request.ReleaseYear, request.PictureIntentId),
                cancellationToken);

            return result.ToHttpResult();
        }

        private static async Task<IResult> DeleteAlbum(
            IMediator mediator,
            CurrentUser currentUser,
            Guid id,
            CancellationToken cancellationToken)
        {
            var result = await mediator.Send(new DeleteAlbumCommand(currentUser.RequiredId, id), cancellationToken);
            return result.ToHttpResult();
        }

        private static async Task<IResult> AddAlbumTracks(
            IMediator mediator,
            CurrentUser currentUser,
            Guid id,
            AddTracksRequest request,
            CancellationToken cancellationToken)
        {
            var result = await mediator.Send(
                new AddTracksToAlbumCommand(currentUser.RequiredId, id, request.TrackIds),
                cancellationToken);

            return result.ToHttpResult();
        }

        private static async Task<IResult> RemoveTrackFromAlbum(
            IMediator mediator,
            CurrentUser currentUser,
            Guid id,
            Guid trackId,
            CancellationToken cancellationToken)
        {
            var result = await mediator.Send(
                new RemoveTrackFromAlbumCommand(currentUser.RequiredId, id, trackId),
                cancellationToken);

            return result.ToHttpResult();
        }
    }
}