using MassTransit;
using Musify.Application.Events;

namespace Musify.Infrastructure.MassTransit.Sagas
{
    public sealed class TrackProcessingStateMachine : MassTransitStateMachine<TrackProcessingState>
    {
        public State Processing { get; private set; } = null!;
        public State Failed { get; private set; } = null!;

        public Event<CreateTrackResourcesEvent> ProcessingStarted { get; private set; } = null!;
        public Event<TrackPictureProcessed> PictureProcessed { get; private set; } = null!;
        public Event<TrackAudioProcessed> AudioProcessed { get; private set; } = null!;
        public Event<TrackPictureProcessingFailed> PictureFailed { get; private set; } = null!;
        public Event<TrackAudioProcessingFailed> AudioFailed { get; private set; } = null!;

        public TrackProcessingStateMachine()
        {
            InstanceState(state => state.CurrentState);

            Event(() => ProcessingStarted, config => config.CorrelateById(context => context.Message.TrackId));
            Event(() => PictureProcessed, config => config.CorrelateById(context => context.Message.TrackId));
            Event(() => AudioProcessed, config => config.CorrelateById(context => context.Message.TrackId));
            Event(() => PictureFailed, config => config.CorrelateById(context => context.Message.TrackId));
            Event(() => AudioFailed, config => config.CorrelateById(context => context.Message.TrackId));

            Initially(
                When(ProcessingStarted)
                    .Then(context =>
                    {
                        context.Saga.CreatedAt = DateTime.UtcNow;
                        context.Saga.UpdatedAt = DateTime.UtcNow;
                    })
                    .TransitionTo(Processing));

            During(Processing,
                When(PictureProcessed)
                    .Then(context =>
                    {
                        context.Saga.PictureProcessed = true;
                        context.Saga.UpdatedAt = DateTime.UtcNow;
                    })
                    .If(context => context.Saga.AudioProcessed, binder => binder.Finalize()),
                When(AudioProcessed)
                    .Then(context =>
                    {
                        context.Saga.AudioProcessed = true;
                        context.Saga.UpdatedAt = DateTime.UtcNow;
                    })
                    .If(context => context.Saga.PictureProcessed, binder => binder.Finalize()),
                When(PictureFailed)
                    .Then(context => context.Saga.UpdatedAt = DateTime.UtcNow)
                    .TransitionTo(Failed),
                When(AudioFailed)
                    .Then(context => context.Saga.UpdatedAt = DateTime.UtcNow)
                    .TransitionTo(Failed));

            During(Failed,
                Ignore(PictureProcessed),
                Ignore(AudioProcessed),
                Ignore(PictureFailed),
                Ignore(AudioFailed));

            SetCompletedWhenFinalized();
        }
    }
}