using MoonTools.ECS;
using Nerfed.Runtime.Scheduling;

namespace Nerfed.Runtime.Systems.Synthetic;

public sealed class DummyLongJobProducerSystem : MoonTools.ECS.System, IParallelSystemMetadata
{
    private readonly JobSystem jobs;
    private readonly DummyLongJobSharedState state;
    private readonly TimeSpan duration;
    private readonly DummyWorkloadMode mode;
    private readonly JobDeadlineMode deadline;
    private int seed;

    public DummyLongJobProducerSystem(
        World world,
        DummyLongJobSharedState state,
        JobSystem jobs,
        TimeSpan duration,
        DummyWorkloadMode mode,
        JobDeadlineMode deadline,
        int initialSeed = 1) : base(world)
    {
        this.state = state;
        this.jobs = jobs;
        this.duration = duration;
        this.mode = mode;
        this.deadline = deadline;
        seed = initialSeed;
    }

    public string ScheduleName => nameof(DummyLongJobProducerSystem);

    // Producer pattern: reads current world state and emits immutable job payload.
    public SystemAccessDeclaration AccessDeclaration => SystemAccessDeclaration.Empty;

    public override void Update(TimeSpan delta)
    {
        if (state.InFlight.IsValid)
        {
            return;
        }

        int capturedSeed = seed;
        state.InFlight = jobs.Submit(
            () => state.LastResult = DummyWorkloadRunner.Run(duration, mode, capturedSeed),
            deadline,
            nameof(DummyLongJobProducerSystem));

        seed = unchecked(capturedSeed + 1);
        state.SubmitCount++;
    }
}