using System.Collections;
using System.Linq;
using System.Numerics;
using System.Threading;
using System.Threading.Tasks;
using Content.Server.Atmos;
using Content.Server.Atmos.Components;
using Content.Server.Atmos.EntitySystems;
using Robust.Shared.CPUJob.JobQueues;
using Content.Server.Ghost.Roles.Components;
using Content.Server.Parallax;
using Content.Server.Procedural;
using Content.Server.Salvage.Expeditions;
using Content.Server.Salvage.Expeditions.Structure;
using Content.Shared.Atmos;
using Content.Shared.Construction.EntitySystems;
using Content.Shared.Dataset;
using Content.Shared.Gravity;
using Content.Shared.Parallax.Biomes;
using Content.Shared.Physics;
using Content.Shared.Procedural;
using Content.Shared.Procedural.Loot;
using Content.Shared.Random;
using Content.Shared.Salvage;
using Content.Shared.Salvage.Expeditions;
using Content.Shared.Salvage.Expeditions.Modifiers;
using Content.Shared.Storage;
using Robust.Shared.Collections;
using Robust.Shared.Map;
using Robust.Shared.Map.Components;
using Robust.Shared.Prototypes;
using Robust.Shared.Random;
using Robust.Shared.Timing;
using Robust.Shared.Utility;

namespace Content.Server.Salvage;

public sealed class SpawnSalvageMissionJob : Job<bool>
{
    private readonly IEntityManager _entManager;
    private readonly IGameTiming _timing;
    private readonly IMapManager _mapManager;
    private readonly IPrototypeManager _prototypeManager;
    private readonly AnchorableSystem _anchorable;
    private readonly BiomeSystem _biome;
    private readonly DungeonSystem _dungeon;
    private readonly MetaDataSystem _metaData;

    public readonly EntityUid Station;
    private readonly SalvageMissionParams _missionParams;

    private readonly ISawmill _sawmill;

    public SpawnSalvageMissionJob(
        double maxTime,
        IEntityManager entManager,
        IGameTiming timing,
        ILogManager logManager,
        IMapManager mapManager,
        IPrototypeManager protoManager,
        AnchorableSystem anchorable,
        BiomeSystem biome,
        DungeonSystem dungeon,
        MetaDataSystem metaData,
        EntityUid station,
        SalvageMissionParams missionParams,
        CancellationToken cancellation = default) : base(maxTime, cancellation)
    {
        _entManager = entManager;
        _timing = timing;
        _mapManager = mapManager;
        _prototypeManager = protoManager;
        _anchorable = anchorable;
        _biome = biome;
        _dungeon = dungeon;
        _metaData = metaData;
        Station = station;
        _missionParams = missionParams;
        _sawmill = logManager.GetSawmill("salvage_job");
#if !DEBUG
        _sawmill.Level = LogLevel.Info;
#endif
    }

    protected override async Task<bool> Process()
    {
        _sawmill.Debug("salvage", $"Spawning salvage mission with seed {_missionParams.Seed}");
        var mapId = _mapManager.CreateMap();
        var mapUid = _mapManager.GetMapEntityId(mapId);
        _mapManager.AddUninitializedMap(mapId);
        MetaDataComponent? metadata = null;
        var grid = _entManager.EnsureComponent<MapGridComponent>(mapUid);
        var random = new Random(_missionParams.Seed);

        // Setup mission configs
        // As we go through the config the rating will deplete so we'll go for most important to least important.
        var difficultyId = "Moderate";
        var difficultyProto = _prototypeManager.Index<SalvageDifficultyPrototype>(difficultyId);

        var mission = _entManager.System<SharedSalvageSystem>()
            .GetMission(difficultyProto, _missionParams.Seed);

        var missionBiome = _prototypeManager.Index<SalvageBiomeModPrototype>(mission.Biome);

        if (missionBiome.BiomePrototype != null)
        {
            var biome = _entManager.AddComponent<BiomeComponent>(mapUid);
            var biomeSystem = _entManager.System<BiomeSystem>();
            biomeSystem.SetTemplate(biome, _prototypeManager.Index<BiomeTemplatePrototype>(missionBiome.BiomePrototype));
            biomeSystem.SetSeed(biome, mission.Seed);
            _entManager.Dirty(biome);

            // Gravity
            var gravity = _entManager.EnsureComponent<GravityComponent>(mapUid);
            gravity.Enabled = true;
            _entManager.Dirty(gravity, metadata);

            // Atmos
            var air = _prototypeManager.Index<SalvageAirMod>(mission.Air);
            // copy into a new array since the yml deserialization discards the fixed length
            var moles = new float[Atmospherics.AdjustedNumberOfGases];
            air.Gases.CopyTo(moles, 0);
            var atmos = _entManager.EnsureComponent<MapAtmosphereComponent>(mapUid);
            _entManager.System<AtmosphereSystem>().SetMapSpace(mapUid, air.Space, atmos);
            _entManager.System<AtmosphereSystem>().SetMapGasMixture(mapUid, new GasMixture(2500)
            {
                Temperature = mission.Temperature,
                Moles = moles,
            }, atmos);

            if (mission.Color != null)
            {
                var lighting = _entManager.EnsureComponent<MapLightComponent>(mapUid);
                lighting.AmbientLightColor = mission.Color.Value;
                _entManager.Dirty(mapUid, lighting);
            }
        }

        _mapManager.DoMapInitialize(mapId);
        _mapManager.SetMapPaused(mapId, true);

        // Setup expedition
        var expedition = _entManager.AddComponent<SalvageExpeditionComponent>(mapUid);
        expedition.Station = Station;
        expedition.EndTime = _timing.CurTime + mission.Duration;
        expedition.MissionParams = _missionParams;

        // Don't want consoles to have the incorrect name until refreshed.
        var ftlUid = _entManager.CreateEntityUninitialized("FTLPoint", new EntityCoordinates(mapUid, grid.TileSizeHalfVector));
        _metaData.SetEntityName(ftlUid, SharedSalvageSystem.GetFTLName(_prototypeManager.Index<DatasetPrototype>("names_borer"), _missionParams.Seed));
        _entManager.InitializeAndStartEntity(ftlUid);

        var landingPadRadius = 24;
        var minDungeonOffset = landingPadRadius + 4;

        // We'll use the dungeon rotation as the spawn angle
        var dungeonRotation = _dungeon.GetDungeonRotation(_missionParams.Seed);

        var maxDungeonOffset = minDungeonOffset + 12;
        var dungeonOffsetDistance = minDungeonOffset + (maxDungeonOffset - minDungeonOffset) * random.NextFloat();
        var dungeonOffset = new Vector2(0f, dungeonOffsetDistance);
        dungeonOffset = dungeonRotation.RotateVec(dungeonOffset);
        var dungeonMod = _prototypeManager.Index<SalvageDungeonModPrototype>(mission.Dungeon);
        var dungeonConfig = _prototypeManager.Index<DungeonConfigPrototype>(dungeonMod.Proto);
        var dungeon = await WaitAsyncTask(_dungeon.GenerateDungeonAsync(dungeonConfig, mapUid, grid, (Vector2i) dungeonOffset,
            _missionParams.Seed));

        // Aborty
        if (dungeon.Rooms.Count == 0)
        {
            return false;
        }

        expedition.DungeonLocation = dungeonOffset;

        List<Vector2i> reservedTiles = new();

        foreach (var tile in grid.GetTilesIntersecting(new Circle(Vector2.Zero, landingPadRadius), false))
        {
            if (!_biome.TryGetBiomeTile(mapUid, grid, tile.GridIndices, out _))
                continue;

            reservedTiles.Add(tile.GridIndices);
        }

        var budgetEntries = new List<IBudgetEntry>();

        /*
         * GUARANTEED LOOT
         */

        // We'll always add this loot if possible
        // mainly used for ore layers.
        foreach (var lootProto in _prototypeManager.EnumeratePrototypes<SalvageLootPrototype>())
        {
            if (!lootProto.Guaranteed)
                continue;

            await SpawnDungeonLoot(dungeon, missionBiome, lootProto, mapUid, grid, random, reservedTiles);
        }

        // Handle boss loot (when relevant).

        // Handle mob loot.

        // Handle remaining loot

        /*
         * MOB SPAWNS
         */

        var mobBudget = difficultyProto.MobBudget;
        var faction = _prototypeManager.Index<SalvageFactionPrototype>(mission.Faction);
        var randomSystem = _entManager.System<RandomSystem>();

        foreach (var entry in faction.MobGroups)
        {
            budgetEntries.Add(entry);
        }

        var probSum = budgetEntries.Sum(x => x.Prob);

        while (mobBudget > 0f)
        {
            var entry = randomSystem.GetBudgetEntry(ref mobBudget, ref probSum, budgetEntries, random);
            if (entry == null)
                break;

            await SpawnRandomEntry(grid, entry, dungeon, random);
        }

        var allLoot = _prototypeManager.Index<SalvageLootPrototype>(SharedSalvageSystem.ExpeditionsLootProto);
        var lootBudget = difficultyProto.LootBudget;

        foreach (var rule in allLoot.LootRules)
        {
            switch (rule)
            {
                case RandomSpawnsLoot randomLoot:
                    budgetEntries.Clear();

                    foreach (var entry in randomLoot.Entries)
                    {
                        budgetEntries.Add(entry);
                    }

                    probSum = budgetEntries.Sum(x => x.Prob);

                    while (lootBudget > 0f)
                    {
                        var entry = randomSystem.GetBudgetEntry(ref lootBudget, ref probSum, budgetEntries, random);
                        if (entry == null)
                            break;

                        _sawmill.Debug($"Spawning dungeon loot {entry.Proto}");
                        await SpawnRandomEntry(grid, entry, dungeon, random);
                    }
                    break;
                default:
                    throw new NotImplementedException();
            }
        }

        return true;
    }

    private async Task SpawnRandomEntry(MapGridComponent grid, IBudgetEntry entry, Dungeon dungeon, Random random)
    {
        await SuspendIfOutOfTime();

        var availableRooms = new ValueList<DungeonRoom>(dungeon.Rooms);
        var availableTiles = new List<Vector2i>();

        while (availableRooms.Count > 0)
        {
            availableTiles.Clear();
            var roomIndex = random.Next(availableRooms.Count);
            var room = availableRooms.RemoveSwap(roomIndex);
            availableTiles.AddRange(room.Tiles);

            while (availableTiles.Count > 0)
            {
                var tile = availableTiles.RemoveSwap(random.Next(availableTiles.Count));

                if (!_anchorable.TileFree(grid, tile, (int) CollisionGroup.MachineLayer,
                        (int) CollisionGroup.MachineLayer))
                {
                    continue;
                }

                var uid = _entManager.SpawnAtPosition(entry.Proto, grid.GridTileToLocal(tile));
                _entManager.RemoveComponent<GhostRoleComponent>(uid);
                _entManager.RemoveComponent<GhostTakeoverAvailableComponent>(uid);
                return;
            }
        }

        // oh noooooooooooo
    }

    private async Task SpawnDungeonLoot(Dungeon dungeon, SalvageBiomeModPrototype biomeMod, SalvageLootPrototype loot, EntityUid gridUid, MapGridComponent grid, Random random, List<Vector2i> reservedTiles)
    {
        for (var i = 0; i < loot.LootRules.Count; i++)
        {
            var rule = loot.LootRules[i];

            switch (rule)
            {
                case BiomeMarkerLoot biomeLoot:
                    {
                        if (_entManager.TryGetComponent<BiomeComponent>(gridUid, out var biome) &&
                            biomeLoot.Prototype.TryGetValue(biomeMod.ID, out var mod))
                        {
                            _biome.AddMarkerLayer(biome, mod);
                        }
                    }
                    break;
                case BiomeTemplateLoot biomeLoot:
                    {
                        if (_entManager.TryGetComponent<BiomeComponent>(gridUid, out var biome))
                        {
                            _biome.AddTemplate(biome, "Loot", _prototypeManager.Index<BiomeTemplatePrototype>(biomeLoot.Prototype), i);
                        }
                    }
                    break;
            }
        }
    }
}