using NeonSprawl.Server.Game.Combat;
using NeonSprawl.Server.Game.Npc;
using Xunit;

namespace NeonSprawl.Server.Tests.Game.Npc;

public sealed class NpcRuntimeOperationsTests
{
    private static readonly DateTimeOffset T0 =
        new(2026, 5, 27, 12, 0, 0, TimeSpan.Zero);

    private static (INpcRuntimeStateStore Runtime, IThreatStateStore Threat, INpcBehaviorDefinitionRegistry Behavior, InMemoryCombatEntityHealthStore CombatHealth, IPlayerCombatHealthStore PlayerHealth)
        CreateFixture()
    {
        return (
            new InMemoryNpcRuntimeStateStore(),
            new InMemoryThreatStateStore(),
            PrototypeNpcTestFixtures.CreateBehaviorRegistry(),
            PrototypeNpcTestFixtures.CreateHealthStore(),
            new InMemoryPlayerCombatHealthStore());
    }

    private static void SetHolder(IThreatStateStore threatStore, string npcId, string playerId = "dev-local-1") =>
        _ = threatStore.TrySetHolder(npcId, playerId);

    private static void Advance(
        DateTimeOffset nowUtc,
        INpcRuntimeStateStore runtimeStore,
        IThreatStateStore threatStore,
        INpcBehaviorDefinitionRegistry behaviorRegistry,
        InMemoryCombatEntityHealthStore combatHealthStore,
        IPlayerCombatHealthStore playerHealthStore,
        double maxDeltaSeconds = NpcRuntimeOperations.DefaultMaxDeltaSeconds) =>
        NpcRuntimeOperations.AdvanceAll(
            nowUtc,
            runtimeStore,
            threatStore,
            behaviorRegistry,
            combatHealthStore,
            playerHealthStore,
            maxDeltaSeconds);

    [Fact]
    public void AdvanceAll_ShouldKeepIdle_WhenNoAggroHolder()
    {
        // Arrange
        var (runtime, threat, behavior, combatHealth, playerHealth) = CreateFixture();
        // Act
        Advance(T0, runtime, threat, behavior, combatHealth, playerHealth);
        // Assert
        runtime.TryGet(PrototypeNpcRegistry.PrototypeNpcMeleeId, out var snapshot);
        Assert.Equal(NpcBehaviorState.Idle, snapshot.BehaviorState);
        Assert.Null(snapshot.ActiveTelegraph);
    }

    [Fact]
    public void AdvanceAll_ShouldEnterAggro_WhenHolderSetAndRowIdle()
    {
        // Arrange
        var (runtime, threat, behavior, combatHealth, playerHealth) = CreateFixture();
        SetHolder(threat, PrototypeNpcRegistry.PrototypeNpcMeleeId);
        // Act
        Advance(T0, runtime, threat, behavior, combatHealth, playerHealth);
        // Assert
        runtime.TryGet(PrototypeNpcRegistry.PrototypeNpcMeleeId, out var snapshot);
        Assert.Equal(NpcBehaviorState.Aggro, snapshot.BehaviorState);
        Assert.Equal(T0, snapshot.PhaseStartedUtc);
        Assert.Null(snapshot.ActiveTelegraph);
    }

    [Fact]
    public void AdvanceAll_ShouldNotTelegraph_WhenNoAggroHolder()
    {
        // Arrange
        var (runtime, threat, behavior, combatHealth, playerHealth) = CreateFixture();
        runtime.LastAdvancedUtc = T0;
        // Act
        Advance(T0.AddSeconds(10), runtime, threat, behavior, combatHealth, playerHealth);
        // Assert
        runtime.TryGet(PrototypeNpcRegistry.PrototypeNpcMeleeId, out var snapshot);
        Assert.Equal(NpcBehaviorState.Idle, snapshot.BehaviorState);
        Assert.Null(snapshot.ActiveTelegraph);
    }

    [Fact]
    public void AdvanceAll_ShouldEnterTelegraphAfterMeleeAttackCooldownSeconds()
    {
        // Arrange
        var (runtime, threat, behavior, combatHealth, playerHealth) = CreateFixture();
        SetHolder(threat, PrototypeNpcRegistry.PrototypeNpcMeleeId);
        Advance(T0, runtime, threat, behavior, combatHealth, playerHealth);
        // Act
        Advance(T0.AddSeconds(3), runtime, threat, behavior, combatHealth, playerHealth);
        // Assert
        runtime.TryGet(PrototypeNpcRegistry.PrototypeNpcMeleeId, out var snapshot);
        Assert.Equal(NpcBehaviorState.TelegraphWindup, snapshot.BehaviorState);
        Assert.Equal(T0.AddSeconds(3), snapshot.PhaseStartedUtc);
        Assert.NotNull(snapshot.ActiveTelegraph);
    }

    [Fact]
    public void AdvanceAll_ShouldRemainAggro_BeforeMeleeAttackCooldownCompletes()
    {
        // Arrange
        var (runtime, threat, behavior, combatHealth, playerHealth) = CreateFixture();
        SetHolder(threat, PrototypeNpcRegistry.PrototypeNpcMeleeId);
        Advance(T0, runtime, threat, behavior, combatHealth, playerHealth);
        // Act
        Advance(T0.AddSeconds(2.9), runtime, threat, behavior, combatHealth, playerHealth);
        // Assert
        runtime.TryGet(PrototypeNpcRegistry.PrototypeNpcMeleeId, out var snapshot);
        Assert.Equal(NpcBehaviorState.Aggro, snapshot.BehaviorState);
    }

    [Fact]
    public void AdvanceAll_ShouldRemainTelegraphWindup_BeforeMeleeWindupCompletes()
    {
        // Arrange
        var (runtime, threat, behavior, combatHealth, playerHealth) = CreateFixture();
        SetHolder(threat, PrototypeNpcRegistry.PrototypeNpcMeleeId);
        Advance(T0, runtime, threat, behavior, combatHealth, playerHealth);
        Advance(T0.AddSeconds(3), runtime, threat, behavior, combatHealth, playerHealth);
        // Act
        Advance(T0.AddSeconds(4.4), runtime, threat, behavior, combatHealth, playerHealth);
        // Assert
        runtime.TryGet(PrototypeNpcRegistry.PrototypeNpcMeleeId, out var snapshot);
        Assert.Equal(NpcBehaviorState.TelegraphWindup, snapshot.BehaviorState);
    }

    [Fact]
    public void AdvanceAll_ShouldEnterRecover_WhenMeleeWindupCompletes()
    {
        // Arrange
        var (runtime, threat, behavior, combatHealth, playerHealth) = CreateFixture();
        SetHolder(threat, PrototypeNpcRegistry.PrototypeNpcMeleeId);
        Advance(T0, runtime, threat, behavior, combatHealth, playerHealth);
        Advance(T0.AddSeconds(3), runtime, threat, behavior, combatHealth, playerHealth);
        Advance(T0.AddSeconds(4.4), runtime, threat, behavior, combatHealth, playerHealth);
        // Act
        Advance(T0.AddSeconds(4.5), runtime, threat, behavior, combatHealth, playerHealth);
        // Assert
        runtime.TryGet(PrototypeNpcRegistry.PrototypeNpcMeleeId, out var snapshot);
        Assert.Equal(NpcBehaviorState.Recover, snapshot.BehaviorState);
        Assert.Equal(T0.AddSeconds(4.5), snapshot.PhaseStartedUtc);
        Assert.Null(snapshot.ActiveTelegraph);
    }

    [Fact]
    public void AdvanceAll_ShouldRunFullMeleeCycle_ToSecondTelegraph()
    {
        // Arrange
        var (runtime, threat, behavior, combatHealth, playerHealth) = CreateFixture();
        SetHolder(threat, PrototypeNpcRegistry.PrototypeNpcMeleeId);
        Advance(T0, runtime, threat, behavior, combatHealth, playerHealth);
        Advance(T0.AddSeconds(3), runtime, threat, behavior, combatHealth, playerHealth);
        Advance(T0.AddSeconds(4.5), runtime, threat, behavior, combatHealth, playerHealth);
        // Act
        Advance(T0.AddSeconds(7.5), runtime, threat, behavior, combatHealth, playerHealth);
        // Assert
        runtime.TryGet(PrototypeNpcRegistry.PrototypeNpcMeleeId, out var snapshot);
        Assert.Equal(NpcBehaviorState.TelegraphWindup, snapshot.BehaviorState);
        Assert.Equal(T0.AddSeconds(7.5), snapshot.PhaseStartedUtc);
        Assert.NotNull(snapshot.ActiveTelegraph);
    }

    [Fact]
    public void AdvanceAll_ShouldRunFullMeleeCycle_ToSecondTelegraph_InSingleAdvanceCall()
    {
        // Arrange
        var (runtime, threat, behavior, combatHealth, playerHealth) = CreateFixture();
        SetHolder(threat, PrototypeNpcRegistry.PrototypeNpcMeleeId);
        Advance(T0, runtime, threat, behavior, combatHealth, playerHealth);
        // Act
        Advance(T0.AddSeconds(7.5), runtime, threat, behavior, combatHealth, playerHealth, maxDeltaSeconds: 10);
        // Assert
        runtime.TryGet(PrototypeNpcRegistry.PrototypeNpcMeleeId, out var snapshot);
        Assert.Equal(NpcBehaviorState.TelegraphWindup, snapshot.BehaviorState);
        Assert.Equal(T0.AddSeconds(7.5), snapshot.PhaseStartedUtc);
        Assert.NotNull(snapshot.ActiveTelegraph);
    }

    [Fact]
    public void AdvanceAll_ShouldReturnToIdle_WhenHolderClearedMidWindup()
    {
        // Arrange
        var (runtime, threat, behavior, combatHealth, playerHealth) = CreateFixture();
        SetHolder(threat, PrototypeNpcRegistry.PrototypeNpcMeleeId);
        Advance(T0, runtime, threat, behavior, combatHealth, playerHealth);
        Advance(T0.AddSeconds(3), runtime, threat, behavior, combatHealth, playerHealth);
        _ = threat.TryClearHolder(PrototypeNpcRegistry.PrototypeNpcMeleeId);
        // Act
        Advance(T0.AddSeconds(3.5), runtime, threat, behavior, combatHealth, playerHealth);
        // Assert
        runtime.TryGet(PrototypeNpcRegistry.PrototypeNpcMeleeId, out var snapshot);
        Assert.Equal(NpcBehaviorState.Idle, snapshot.BehaviorState);
        Assert.Null(snapshot.ActiveTelegraph);
    }

    [Theory]
    [InlineData("prototype_npc_ranged", 4.0)]
    [InlineData("prototype_npc_elite", 5.0)]
    public void AdvanceAll_ShouldEnterTelegraph_AtCatalogCooldownForArchetype(
        string npcInstanceId,
        double attackCooldownSeconds)
    {
        // Arrange
        var (runtime, threat, behavior, combatHealth, playerHealth) = CreateFixture();
        SetHolder(threat, npcInstanceId);
        Advance(T0, runtime, threat, behavior, combatHealth, playerHealth);
        // Act
        Advance(T0.AddSeconds(attackCooldownSeconds), runtime, threat, behavior, combatHealth, playerHealth);
        // Assert
        runtime.TryGet(npcInstanceId, out var snapshot);
        Assert.Equal(NpcBehaviorState.TelegraphWindup, snapshot.BehaviorState);
        Assert.Equal(T0.AddSeconds(attackCooldownSeconds), snapshot.PhaseStartedUtc);
    }

    [Theory]
    [InlineData("prototype_npc_ranged", 4.0, 2.0)]
    [InlineData("prototype_npc_elite", 5.0, 2.5)]
    public void AdvanceAll_ShouldEnterRecover_AfterCatalogWindupForArchetype(
        string npcInstanceId,
        double attackCooldownSeconds,
        double telegraphWindupSeconds)
    {
        // Arrange
        var (runtime, threat, behavior, combatHealth, playerHealth) = CreateFixture();
        SetHolder(threat, npcInstanceId);
        Advance(T0, runtime, threat, behavior, combatHealth, playerHealth);
        Advance(T0.AddSeconds(attackCooldownSeconds), runtime, threat, behavior, combatHealth, playerHealth);
        // Act
        Advance(T0.AddSeconds(attackCooldownSeconds + telegraphWindupSeconds), runtime, threat, behavior, combatHealth, playerHealth);
        // Assert
        runtime.TryGet(npcInstanceId, out var snapshot);
        Assert.Equal(NpcBehaviorState.Recover, snapshot.BehaviorState);
        Assert.Equal(
            T0.AddSeconds(attackCooldownSeconds + telegraphWindupSeconds),
            snapshot.PhaseStartedUtc);
    }

    [Fact]
    public void AdvanceAll_ShouldCapSimulatedDelta_PerAdvanceCall()
    {
        // Arrange
        var (runtime, threat, behavior, combatHealth, playerHealth) = CreateFixture();
        SetHolder(threat, PrototypeNpcRegistry.PrototypeNpcMeleeId);
        Advance(T0, runtime, threat, behavior, combatHealth, playerHealth);
        // Act
        Advance(T0.AddSeconds(10), runtime, threat, behavior, combatHealth, playerHealth, maxDeltaSeconds: 5);
        // Assert
        runtime.TryGet(PrototypeNpcRegistry.PrototypeNpcMeleeId, out var snapshot);
        Assert.Equal(NpcBehaviorState.Recover, snapshot.BehaviorState);
        Assert.Equal(T0.AddSeconds(4.5), snapshot.PhaseStartedUtc);
        Assert.Equal(T0.AddSeconds(5), runtime.LastAdvancedUtc);
    }

    [Fact]
    public void AdvanceAll_ShouldPreserveGradualCatchUp_AfterLongGapWithDeltaCap()
    {
        // Arrange
        var (runtime, threat, behavior, combatHealth, playerHealth) = CreateFixture();
        SetHolder(threat, PrototypeNpcRegistry.PrototypeNpcMeleeId);
        Advance(T0, runtime, threat, behavior, combatHealth, playerHealth);
        Advance(T0.AddSeconds(100), runtime, threat, behavior, combatHealth, playerHealth, maxDeltaSeconds: 5);
        // Act
        Advance(T0.AddSeconds(100.5), runtime, threat, behavior, combatHealth, playerHealth, maxDeltaSeconds: 5);
        // Assert
        Assert.Equal(T0.AddSeconds(10), runtime.LastAdvancedUtc);
        runtime.TryGet(PrototypeNpcRegistry.PrototypeNpcMeleeId, out var snapshot);
        Assert.Equal(NpcBehaviorState.Recover, snapshot.BehaviorState);
        Assert.Equal(T0.AddSeconds(9), snapshot.PhaseStartedUtc);
    }

    [Fact]
    public void ResetAllPrototypeRows_ShouldClearLastAdvancedUtc_ForFreshAdvanceBaseline()
    {
        // Arrange
        var (runtime, threat, behavior, combatHealth, playerHealth) = CreateFixture();
        SetHolder(threat, PrototypeNpcRegistry.PrototypeNpcMeleeId);
        Advance(T0, runtime, threat, behavior, combatHealth, playerHealth);
        runtime.LastAdvancedUtc = T0.AddHours(1);
        NpcRuntimeOperations.ResetAllPrototypeRows(runtime);
        SetHolder(threat, PrototypeNpcRegistry.PrototypeNpcMeleeId);
        // Act
        Advance(T0.AddHours(1).AddSeconds(10), runtime, threat, behavior, combatHealth, playerHealth, maxDeltaSeconds: 5);
        // Assert
        runtime.TryGet(PrototypeNpcRegistry.PrototypeNpcMeleeId, out var snapshot);
        Assert.Equal(NpcBehaviorState.Aggro, snapshot.BehaviorState);
        Assert.Equal(T0.AddHours(1).AddSeconds(10), snapshot.PhaseStartedUtc);
        Assert.Equal(T0.AddHours(1).AddSeconds(10), runtime.LastAdvancedUtc);
    }

    [Fact]
    public void AdvanceAll_ShouldPreserveLastAdvancedUtc_WhenClockRegresses()
    {
        // Arrange
        var (runtime, threat, behavior, combatHealth, playerHealth) = CreateFixture();
        Advance(T0, runtime, threat, behavior, combatHealth, playerHealth);
        runtime.LastAdvancedUtc = T0.AddSeconds(10);
        // Act
        Advance(T0.AddSeconds(5), runtime, threat, behavior, combatHealth, playerHealth);
        // Assert
        Assert.Equal(T0.AddSeconds(10), runtime.LastAdvancedUtc);
    }

    [Fact]
    public void AdvanceAll_ShouldApplyPlayerDamage_WhenMeleeWindupCompletes()
    {
        // Arrange
        var (runtime, threat, behavior, combatHealth, playerHealth) = CreateFixture();
        SetHolder(threat, PrototypeNpcRegistry.PrototypeNpcMeleeId);
        Advance(T0, runtime, threat, behavior, combatHealth, playerHealth);
        Advance(T0.AddSeconds(3), runtime, threat, behavior, combatHealth, playerHealth);
        Advance(T0.AddSeconds(4.4), runtime, threat, behavior, combatHealth, playerHealth);
        // Act
        Advance(T0.AddSeconds(4.5), runtime, threat, behavior, combatHealth, playerHealth);
        // Assert
        playerHealth.TryGet("dev-local-1", out var snapshot);
        Assert.Equal(85, snapshot.CurrentHp);
    }

    [Fact]
    public void AdvanceAll_ShouldNotApplyPlayerDamage_WhenHolderClearedBeforeWindupCompletes()
    {
        // Arrange
        var (runtime, threat, behavior, combatHealth, playerHealth) = CreateFixture();
        SetHolder(threat, PrototypeNpcRegistry.PrototypeNpcMeleeId);
        Advance(T0, runtime, threat, behavior, combatHealth, playerHealth);
        Advance(T0.AddSeconds(3), runtime, threat, behavior, combatHealth, playerHealth);
        _ = threat.TryClearHolder(PrototypeNpcRegistry.PrototypeNpcMeleeId);
        // Act
        Advance(T0.AddSeconds(4.5), runtime, threat, behavior, combatHealth, playerHealth);
        // Assert
        playerHealth.TryGet("dev-local-1", out var snapshot);
        Assert.Equal(PlayerCombatHealthDefaults.MaxHp, snapshot.CurrentHp);
        runtime.TryGet(PrototypeNpcRegistry.PrototypeNpcMeleeId, out var runtimeSnapshot);
        Assert.Equal(NpcBehaviorState.Idle, runtimeSnapshot.BehaviorState);
    }

    [Fact]
    public void HasPositiveTimingDurations_ShouldRejectNonPositiveCatalogTimings()
    {
        // Arrange
        var invalidCooldown = new NpcBehaviorDefRow(
            "bad",
            "Bad",
            "melee_pressure",
            100,
            8.0,
            16.0,
            1.5,
            15,
            0.0);
        var invalidWindup = invalidCooldown with { Id = "bad2", TelegraphWindupSeconds = 0.0 };
        var valid = invalidCooldown with { AttackCooldownSeconds = 3.0, TelegraphWindupSeconds = 1.5 };
        // Act
        var cooldownOk = NpcRuntimeOperations.HasPositiveTimingDurations(invalidCooldown);
        var windupOk = NpcRuntimeOperations.HasPositiveTimingDurations(invalidWindup);
        var validOk = NpcRuntimeOperations.HasPositiveTimingDurations(valid);
        // Assert
        Assert.False(cooldownOk);
        Assert.False(windupOk);
        Assert.True(validOk);
    }

    [Fact]
    public void TryStopOnTargetDefeat_ShouldClearAggroAndIdleRuntime()
    {
        // Arrange
        var (runtime, threat, behavior, combatHealth, playerHealth) = CreateFixture();
        SetHolder(threat, PrototypeNpcRegistry.PrototypeNpcMeleeId);
        Advance(T0, runtime, threat, behavior, combatHealth, playerHealth);
        Advance(T0.AddSeconds(3), runtime, threat, behavior, combatHealth, playerHealth);
        _ = combatHealth.TryApplyDamage(PrototypeNpcRegistry.PrototypeNpcMeleeId, 100, out _);
        // Act
        NpcRuntimeOperations.TryStopOnTargetDefeat(
            PrototypeNpcRegistry.PrototypeNpcMeleeId,
            combatHealth,
            threat,
            runtime);
        // Assert
        threat.TryGet(PrototypeNpcRegistry.PrototypeNpcMeleeId, out var threatRow);
        Assert.Null(threatRow.AggroHolderPlayerId);
        runtime.TryGet(PrototypeNpcRegistry.PrototypeNpcMeleeId, out var runtimeRow);
        Assert.Equal(NpcBehaviorState.Idle, runtimeRow.BehaviorState);
        Assert.Null(runtimeRow.ActiveTelegraph);
    }

    [Fact]
    public void AdvanceAll_ShouldNotApplyPlayerDamage_WhenNpcTargetDefeated()
    {
        // Arrange
        var (runtime, threat, behavior, combatHealth, playerHealth) = CreateFixture();
        SetHolder(threat, PrototypeNpcRegistry.PrototypeNpcMeleeId);
        Advance(T0, runtime, threat, behavior, combatHealth, playerHealth);
        Advance(T0.AddSeconds(3), runtime, threat, behavior, combatHealth, playerHealth);
        _ = combatHealth.TryApplyDamage(PrototypeNpcRegistry.PrototypeNpcMeleeId, 100, out _);
        NpcRuntimeOperations.TryStopOnTargetDefeat(
            PrototypeNpcRegistry.PrototypeNpcMeleeId,
            combatHealth,
            threat,
            runtime);
        // Act
        Advance(T0.AddSeconds(30), runtime, threat, behavior, combatHealth, playerHealth);
        // Assert
        playerHealth.TryGet("dev-local-1", out var snapshot);
        Assert.Equal(PlayerCombatHealthDefaults.MaxHp, snapshot.CurrentHp);
    }
}