using System.Threading;
using Content.Shared.Weather;
using Robust.Shared.CPUJob.JobQueues;
using Robust.Shared.CPUJob.JobQueues.Queues;
using Robust.Shared.Map.Components;
using Robust.Shared.Prototypes;
using Robust.Shared.Random;
using Robust.Shared.Timing;

namespace Content.Server._CP14.WeatherEffect;

public sealed class CP14WeatherEffectSystem : EntitySystem
{
    [Dependency] private readonly IPrototypeManager _proto = default!;
    [Dependency] private readonly EntityLookupSystem _lookup = default!;
    [Dependency] private readonly SharedWeatherSystem _weather = default!;
    [Dependency] private readonly SharedMapSystem _mapSystem = default!;
    [Dependency] private readonly IRobustRandom _random = default!;
    [Dependency] private readonly IGameTiming _timing = default!;

    private readonly JobQueue _weatherQueue = new();
    private readonly List<(CP14WeatherEffectJob Job, CancellationTokenSource CancelToken)> _weatherJobs = new();
    private const double JobMaxTime = 0.002;

    private readonly TimeSpan ProcessFreq = TimeSpan.FromSeconds(5f);
    private TimeSpan NextProcessTime = TimeSpan.Zero;

    private EntityQuery<BlockWeatherComponent> _weatherBlockQuery;
    public override void Initialize()
    {
        base.Initialize();

        _weatherBlockQuery = GetEntityQuery<BlockWeatherComponent>();

        NextProcessTime = _timing.CurTime + ProcessFreq;
    }

    public override void Update(float frameTime)
    {
        base.Update(frameTime);
        _weatherQueue.Process();

        foreach (var (job, cancelToken) in _weatherJobs.ToArray())
        {
            switch (job.Status)
            {
                case JobStatus.Finished:
                    _weatherJobs.Remove((job, cancelToken));
                    break;
            }
        }

        if (_timing.CurTime <= NextProcessTime)
            return;

        NextProcessTime = _timing.CurTime + ProcessFreq;
        ProcessWeather();
    }

    private void ProcessWeather()
    {
        var query = EntityQueryEnumerator<WeatherComponent, MapGridComponent>();
        while (query.MoveNext(out var mapUid, out var weather, out var mapComp))
        {
            foreach (var (proto, data) in weather.Weather)
            {
                if (!_proto.TryIndex(proto, out var indexedWeather))
                    continue;

                var cancelToken = new CancellationTokenSource();
                var job = new CP14WeatherEffectJob(
                    JobMaxTime,
                    EntityManager,
                    _lookup,
                    _weather,
                    _mapSystem,
                    _random,
                    (mapUid, mapComp),
                    Transform(mapUid).MapID,
                    indexedWeather.Effects,
                    _weatherBlockQuery);

                _weatherJobs.Add((job, cancelToken));
                _weatherQueue.EnqueueJob(job);
            }
        }
    }
}