using AcDream.App.Streaming;
using Xunit;

namespace AcDream.Core.Tests.Streaming;

/// <summary>
/// The GameWindow side of the dungeon streaming gate (AP-36): given the player's
/// CURRENT cell, decide whether to collapse streaming and where to pin the observer.
/// The StreamingController's reaction to these inputs is covered by
/// <see cref="StreamingControllerDungeonGateTests"/>; this fixture covers the
/// INPUT computation — in particular the teleport-hold rule (#145/#138).
/// </summary>
public class DungeonStreamingGateTests
{
    // A 0x0007 Town Network dungeon cell (landblock 0x0007, cell 0x0145).
    private const uint DungeonCell = 0x00070145u;
    // An outdoor terrain cell near Holtburg (landblock 0xAB34, structure cell 0x0001).
    private const uint OutdoorCell = 0xAB340001u;

    [Fact]
    public void SealedDungeonCell_NotHold_CollapsesAndPinsObserverToCellLandblock()
    {
        var r = DungeonStreamingGate.Compute(
            isTeleportHold: false, currCellIsSealedDungeon: true, currCellId: DungeonCell);

        Assert.True(r.InsideDungeon);
        Assert.Equal(0x0007u, r.ObserverLandblockKey); // 0x00070145 >> 16
    }

    [Fact]
    public void OutdoorCell_NotHold_NoCollapse_NoObserverOverride()
    {
        var r = DungeonStreamingGate.Compute(
            isTeleportHold: false, currCellIsSealedDungeon: false, currCellId: OutdoorCell);

        Assert.False(r.InsideDungeon);
        Assert.Null(r.ObserverLandblockKey);
    }

    [Fact]
    public void TeleportHold_StaleSealedDungeonCurrCell_SuppressesGate()
    {
        // #145/#138 — teleport OUT of a dungeon. During the arrival hold the player is
        // unplaced, so CurrCell is still the frozen SOURCE dungeon cell. The gate MUST be
        // suppressed: streaming has to follow the DESTINATION (the PortalSpace observer
        // pin), not re-pin onto the source dungeon. The pre-fix logic returned
        // (true, 0x0007) here, which kept streaming collapsed on the source dungeon → the
        // outdoor destination never hydrated → 600-frame timeout → force-snap to ocean.
        var r = DungeonStreamingGate.Compute(
            isTeleportHold: true, currCellIsSealedDungeon: true, currCellId: DungeonCell);

        Assert.False(r.InsideDungeon);
        Assert.Null(r.ObserverLandblockKey);
    }

    [Fact]
    public void TeleportHold_OutdoorCurrCell_AlsoNoCollapse()
    {
        // Sanity: an outdoor→outdoor or building→outdoor hold is already correct, but the
        // suppression rule must not change that.
        var r = DungeonStreamingGate.Compute(
            isTeleportHold: true, currCellIsSealedDungeon: false, currCellId: OutdoorCell);

        Assert.False(r.InsideDungeon);
        Assert.Null(r.ObserverLandblockKey);
    }
}