using Microsoft.Extensions.Options;
using NeonSprawl.Server.Game.Npc;
using NeonSprawl.Server.Game.PositionState;
using Xunit;

namespace NeonSprawl.Server.Tests.Game.Npc;

public sealed class AggroOperationsTests
{
    private static InMemoryPositionStateStore CreatePositionStoreAt(double x, double y, double z)
    {
        var store = new InMemoryPositionStateStore(Options.Create(new GamePositionOptions
        {
            DevPlayerId = "dev-local-1",
            DefaultPosition = new DefaultPositionOptions { X = x, Y = y, Z = z },
        }));
        return store;
    }

    [Fact]
    public void TryAcquire_ShouldSetHolder_WhenRowEmpty()
    {
        // Arrange
        var threatStore = new InMemoryThreatStateStore();
        // Act
        var acquired = AggroOperations.TryAcquire(
            PrototypeNpcRegistry.PrototypeNpcMeleeId,
            "dev-local-1",
            threatStore);
        threatStore.TryGet(PrototypeNpcRegistry.PrototypeNpcMeleeId, out var snapshot);
        // Assert
        Assert.True(acquired);
        Assert.Equal("dev-local-1", snapshot.AggroHolderPlayerId);
    }

    [Fact]
    public void TryAcquire_ShouldNoOp_WhenHolderAlreadySet()
    {
        // Arrange
        var threatStore = new InMemoryThreatStateStore();
        _ = AggroOperations.TryAcquire(PrototypeNpcRegistry.PrototypeNpcMeleeId, "dev-local-1", threatStore);
        // Act
        var secondAcquire = AggroOperations.TryAcquire(
            PrototypeNpcRegistry.PrototypeNpcMeleeId,
            "dev-local-1",
            threatStore);
        threatStore.TryGet(PrototypeNpcRegistry.PrototypeNpcMeleeId, out var snapshot);
        // Assert
        Assert.False(secondAcquire);
        Assert.Equal("dev-local-1", snapshot.AggroHolderPlayerId);
    }

    [Fact]
    public void TryClearOnLeashForPlayer_ShouldClearHolder_WhenPlayerBeyondLeashRadius()
    {
        // Arrange
        var behaviorRegistry = PrototypeNpcTestFixtures.CreateBehaviorRegistry();
        var threatStore = new InMemoryThreatStateStore();
        var positions = CreatePositionStoreAt(0, 0, 0);
        _ = AggroOperations.TryAcquire(PrototypeNpcRegistry.PrototypeNpcMeleeId, "dev-local-1", threatStore);
        positions.TryApplyMoveTarget("dev-local-1", 12, 0, 12, out _);
        // Act
        AggroOperations.TryClearOnLeashForPlayer("dev-local-1", positions, behaviorRegistry, threatStore);
        threatStore.TryGet(PrototypeNpcRegistry.PrototypeNpcMeleeId, out var snapshot);
        // Assert
        Assert.Null(snapshot.AggroHolderPlayerId);
    }

    [Fact]
    public void TryClearOnLeashForPlayer_ShouldKeepHolder_WhenPlayerInsideLeashRadius()
    {
        // Arrange
        var behaviorRegistry = PrototypeNpcTestFixtures.CreateBehaviorRegistry();
        var threatStore = new InMemoryThreatStateStore();
        var positions = CreatePositionStoreAt(0, 0, 0);
        _ = AggroOperations.TryAcquire(PrototypeNpcRegistry.PrototypeNpcMeleeId, "dev-local-1", threatStore);
        positions.TryApplyMoveTarget("dev-local-1", 1, 0, 1, out _);
        // Act
        AggroOperations.TryClearOnLeashForPlayer("dev-local-1", positions, behaviorRegistry, threatStore);
        threatStore.TryGet(PrototypeNpcRegistry.PrototypeNpcMeleeId, out var snapshot);
        // Assert
        Assert.Equal("dev-local-1", snapshot.AggroHolderPlayerId);
    }

    [Fact]
    public void TryClearOnLeashForPlayer_ShouldKeepHolder_WhenPlayerAtExactLeashRadius()
    {
        // Arrange
        var behaviorRegistry = PrototypeNpcTestFixtures.CreateBehaviorRegistry();
        var threatStore = new InMemoryThreatStateStore();
        var positions = CreatePositionStoreAt(0, 0, 0);
        _ = AggroOperations.TryAcquire(PrototypeNpcRegistry.PrototypeNpcMeleeId, "dev-local-1", threatStore);
        // Melee anchor (-3, -3); leash 16.0 — X = 13 is exactly 16 m horizontal from anchor.
        positions.TryApplyMoveTarget("dev-local-1", 13, 0, -3, out _);
        // Act
        AggroOperations.TryClearOnLeashForPlayer("dev-local-1", positions, behaviorRegistry, threatStore);
        threatStore.TryGet(PrototypeNpcRegistry.PrototypeNpcMeleeId, out var snapshot);
        // Assert
        Assert.Equal("dev-local-1", snapshot.AggroHolderPlayerId);
    }

    [Fact]
    public void TryAcquire_ShouldSetHolderAgain_AfterLeashClear()
    {
        // Arrange
        var behaviorRegistry = PrototypeNpcTestFixtures.CreateBehaviorRegistry();
        var threatStore = new InMemoryThreatStateStore();
        var positions = CreatePositionStoreAt(0, 0, 0);
        _ = AggroOperations.TryAcquire(PrototypeNpcRegistry.PrototypeNpcMeleeId, "dev-local-1", threatStore);
        positions.TryApplyMoveTarget("dev-local-1", 12, 0, 12, out _);
        AggroOperations.TryClearOnLeashForPlayer("dev-local-1", positions, behaviorRegistry, threatStore);
        positions.TryApplyMoveTarget("dev-local-1", 0, 0, 0, out _);
        // Act
        var reacquired = AggroOperations.TryAcquire(
            PrototypeNpcRegistry.PrototypeNpcMeleeId,
            "dev-local-1",
            threatStore);
        threatStore.TryGet(PrototypeNpcRegistry.PrototypeNpcMeleeId, out var snapshot);
        // Assert
        Assert.True(reacquired);
        Assert.Equal("dev-local-1", snapshot.AggroHolderPlayerId);
    }
}