using System.Collections.Generic;
using DatReaderWriter.DBObjs;
// Environment collides with System.Environment under implicit usings — alias it.
using DatEnvironment = DatReaderWriter.DBObjs.Environment;

namespace AcDream.Core.World;

/// <summary>
/// The parsed dat objects <c>ApplyLoadedTerrainLocked</c> needs, pre-read by the
/// streaming worker under <c>_datLock</c> so the apply makes ZERO DatCollection
/// calls and the update thread never blocks on the worker's lock (the FPS
/// 30↔200 swing was that lock-wait). Keyed by the same dat id the apply would
/// have passed to <c>_dats.Get&lt;T&gt;</c>.
/// </summary>
public sealed record PhysicsDatBundle(
    LandBlockInfo? Info,
    IReadOnlyDictionary<uint, EnvCell> EnvCells,
    IReadOnlyDictionary<uint, DatEnvironment> Environments,
    IReadOnlyDictionary<uint, Setup> Setups,
    IReadOnlyDictionary<uint, GfxObj> GfxObjs)
{
    /// <summary>Empty bundle for far-tier landblocks (no cells / buildings /
    /// entities) and for non-streaming <see cref="LoadedLandblock"/> construction.</summary>
    public static readonly PhysicsDatBundle Empty = new(
        null,
        new Dictionary<uint, EnvCell>(),
        new Dictionary<uint, DatEnvironment>(),
        new Dictionary<uint, Setup>(),
        new Dictionary<uint, GfxObj>());
}