using System.IO;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Logging.Abstractions;
using NeonSprawl.Server.Game.Npc;
using NeonSprawl.Server.Tests;
using Xunit;

namespace NeonSprawl.Server.Tests.Game.Npc;

public class NpcBehaviorDefinitionRegistryTests
{
    private static NpcBehaviorDefinitionRegistry CreateRegistryFromRows(IReadOnlyDictionary<string, NpcBehaviorDefRow> byId)
    {
        var catalog = new NpcBehaviorDefinitionCatalog("/tmp/npc-behaviors", byId, catalogJsonFileCount: 1);
        return new NpcBehaviorDefinitionRegistry(catalog);
    }

    private static NpcBehaviorDefRow MeleeRow() =>
        new(
            PrototypeNpcBehaviorRegistry.PrototypeMeleePressure,
            "Melee Pressure",
            "melee_pressure",
            100,
            8.0,
            16.0,
            1.5,
            15,
            3.0);

    private static NpcBehaviorDefRow RangedRow() =>
        new(
            PrototypeNpcBehaviorRegistry.PrototypeRangedControl,
            "Ranged Control",
            "ranged_control",
            80,
            10.0,
            20.0,
            2.0,
            12,
            4.0);

    private static NpcBehaviorDefRow EliteRow() =>
        new(
            PrototypeNpcBehaviorRegistry.PrototypeEliteMiniBoss,
            "Elite Mini-Boss",
            "elite_mini_boss",
            200,
            8.0,
            18.0,
            2.5,
            25,
            5.0);

    [Fact]
    public void TryGetDefinition_ShouldReturnTrueAndExpectedMetadata_WhenMeleeExists()
    {
        // Arrange
        var rows = new Dictionary<string, NpcBehaviorDefRow>(StringComparer.Ordinal)
        {
            [PrototypeNpcBehaviorRegistry.PrototypeMeleePressure] = MeleeRow(),
        };
        var registry = CreateRegistryFromRows(rows);
        // Act
        var found = registry.TryGetDefinition(PrototypeNpcBehaviorRegistry.PrototypeMeleePressure, out var def);
        // Assert
        Assert.True(found);
        Assert.NotNull(def);
        Assert.Equal(100, def.MaxHp);
        Assert.Equal(8.0, def.AggroRadius);
        Assert.Equal(16.0, def.LeashRadius);
        Assert.Equal(15, def.AttackDamage);
        Assert.Equal(1.5, def.TelegraphWindupSeconds);
        Assert.Equal("melee_pressure", def.ArchetypeKind);
        Assert.Equal("Melee Pressure", def.DisplayName);
    }

    [Fact]
    public void TryGetDefinition_ShouldReturnTrueAndExpectedMetadata_WhenEliteExists()
    {
        // Arrange
        var rows = new Dictionary<string, NpcBehaviorDefRow>(StringComparer.Ordinal)
        {
            [PrototypeNpcBehaviorRegistry.PrototypeEliteMiniBoss] = EliteRow(),
        };
        var registry = CreateRegistryFromRows(rows);
        // Act
        var found = registry.TryGetDefinition(PrototypeNpcBehaviorRegistry.PrototypeEliteMiniBoss, out var def);
        // Assert
        Assert.True(found);
        Assert.NotNull(def);
        Assert.Equal(200, def.MaxHp);
        Assert.Equal(25, def.AttackDamage);
        Assert.Equal(2.5, def.TelegraphWindupSeconds);
    }

    [Fact]
    public void TryGetDefinition_ShouldReturnFalse_WhenBehaviorIdIsNull()
    {
        // Arrange
        var rows = new Dictionary<string, NpcBehaviorDefRow>(StringComparer.Ordinal)
        {
            [PrototypeNpcBehaviorRegistry.PrototypeMeleePressure] = MeleeRow(),
        };
        var registry = CreateRegistryFromRows(rows);
        // Act
        var found = registry.TryGetDefinition(null, out var def);
        // Assert
        Assert.False(found);
        Assert.Null(def);
    }

    [Fact]
    public void TryGetDefinition_ShouldReturnFalse_WhenIdUnknown()
    {
        // Arrange
        var rows = new Dictionary<string, NpcBehaviorDefRow>(StringComparer.Ordinal)
        {
            [PrototypeNpcBehaviorRegistry.PrototypeMeleePressure] = MeleeRow(),
        };
        var registry = CreateRegistryFromRows(rows);
        // Act
        var found = registry.TryGetDefinition("not_a_real_behavior", out var def);
        // Assert
        Assert.False(found);
        Assert.Null(def);
    }

    [Fact]
    public void TryGetDefinition_ShouldReturnFalse_WhenIdHasMixedCase()
    {
        // Arrange
        var rows = new Dictionary<string, NpcBehaviorDefRow>(StringComparer.Ordinal)
        {
            [PrototypeNpcBehaviorRegistry.PrototypeMeleePressure] = MeleeRow(),
        };
        var registry = CreateRegistryFromRows(rows);
        // Act
        var found = registry.TryGetDefinition("Prototype_Melee_Pressure", out var def);
        // Assert
        Assert.False(found);
        Assert.Null(def);
    }

    [Fact]
    public void TryNormalizeKnown_ShouldReturnTrueAndLowercaseId_WhenInputHasWhitespaceAndMixedCase()
    {
        // Arrange
        var rows = new Dictionary<string, NpcBehaviorDefRow>(StringComparer.Ordinal)
        {
            [PrototypeNpcBehaviorRegistry.PrototypeMeleePressure] = MeleeRow(),
        };
        var registry = CreateRegistryFromRows(rows);
        // Act
        var found = registry.TryNormalizeKnown("  Prototype_Melee_Pressure  ", out var normalized);
        // Assert
        Assert.True(found);
        Assert.Equal(PrototypeNpcBehaviorRegistry.PrototypeMeleePressure, normalized);
    }

    [Fact]
    public void TryNormalizeKnown_ShouldReturnFalse_WhenInputIsNull()
    {
        // Arrange
        var rows = new Dictionary<string, NpcBehaviorDefRow>(StringComparer.Ordinal)
        {
            [PrototypeNpcBehaviorRegistry.PrototypeMeleePressure] = MeleeRow(),
        };
        var registry = CreateRegistryFromRows(rows);
        // Act
        var found = registry.TryNormalizeKnown(null, out var normalized);
        // Assert
        Assert.False(found);
        Assert.Equal(string.Empty, normalized);
    }

    [Fact]
    public void TryNormalizeKnown_ShouldReturnFalse_WhenInputIsWhitespaceOnly()
    {
        // Arrange
        var rows = new Dictionary<string, NpcBehaviorDefRow>(StringComparer.Ordinal)
        {
            [PrototypeNpcBehaviorRegistry.PrototypeMeleePressure] = MeleeRow(),
        };
        var registry = CreateRegistryFromRows(rows);
        // Act
        var found = registry.TryNormalizeKnown("   ", out var normalized);
        // Assert
        Assert.False(found);
        Assert.Equal(string.Empty, normalized);
    }

    [Fact]
    public void TryNormalizeKnown_ShouldReturnFalse_WhenIdNotInCatalog()
    {
        // Arrange
        var rows = new Dictionary<string, NpcBehaviorDefRow>(StringComparer.Ordinal)
        {
            [PrototypeNpcBehaviorRegistry.PrototypeMeleePressure] = MeleeRow(),
        };
        var registry = CreateRegistryFromRows(rows);
        // Act
        var found = registry.TryNormalizeKnown("prototype_unknown", out var normalized);
        // Assert
        Assert.False(found);
        Assert.Equal("prototype_unknown", normalized);
    }

    [Fact]
    public void GetDefinitionsInIdOrder_ShouldListAllRowsOrderedById_WhenMultipleBehaviors()
    {
        // Arrange
        var rows = new Dictionary<string, NpcBehaviorDefRow>(StringComparer.Ordinal)
        {
            [PrototypeNpcBehaviorRegistry.PrototypeRangedControl] = RangedRow(),
            [PrototypeNpcBehaviorRegistry.PrototypeEliteMiniBoss] = EliteRow(),
            [PrototypeNpcBehaviorRegistry.PrototypeMeleePressure] = MeleeRow(),
        };
        var registry = CreateRegistryFromRows(rows);
        // Act
        var list = registry.GetDefinitionsInIdOrder();
        // Assert
        Assert.Equal(3, list.Count);
        Assert.Equal(PrototypeNpcBehaviorRegistry.PrototypeEliteMiniBoss, list[0].Id);
        Assert.Equal(PrototypeNpcBehaviorRegistry.PrototypeMeleePressure, list[1].Id);
        Assert.Equal(PrototypeNpcBehaviorRegistry.PrototypeRangedControl, list[2].Id);
    }

    [Fact]
    public void TryGetDefinition_ShouldMatchLoaderCatalog_WhenUsingPrototypeFixture()
    {
        // Arrange
        var root = Directory.CreateTempSubdirectory("neon-sprawl-npc-registry-loader-");
        try
        {
            var npcBehaviorsDir = Path.Combine(root.FullName, "content", "npc-behaviors");
            var schemaDir = Path.Combine(root.FullName, "content", "schemas");
            Directory.CreateDirectory(npcBehaviorsDir);
            Directory.CreateDirectory(schemaDir);
            var schemaPath = Path.Combine(schemaDir, "npc-behavior-def.schema.json");
            File.Copy(NpcBehaviorCatalogTestPaths.DiscoverRepoNpcBehaviorDefSchemaPath(), schemaPath, overwrite: true);
            File.Copy(
                Path.Combine(NpcBehaviorCatalogTestPaths.DiscoverRepoNpcBehaviorsDirectory(), "prototype_npc_behaviors.json"),
                Path.Combine(npcBehaviorsDir, "prototype_npc_behaviors.json"),
                overwrite: true);
            var loaded = NpcBehaviorDefinitionCatalogLoader.Load(npcBehaviorsDir, schemaPath, NullLogger.Instance);
            var registry = new NpcBehaviorDefinitionRegistry(loaded);
            // Act
            var meleeOk = registry.TryGetDefinition(PrototypeNpcBehaviorRegistry.PrototypeMeleePressure, out var melee);
            var rangedOk = registry.TryGetDefinition(PrototypeNpcBehaviorRegistry.PrototypeRangedControl, out var ranged);
            var eliteOk = registry.TryGetDefinition(PrototypeNpcBehaviorRegistry.PrototypeEliteMiniBoss, out var elite);
            var list = registry.GetDefinitionsInIdOrder();
            // Assert
            Assert.True(meleeOk);
            Assert.NotNull(melee);
            Assert.Equal(100, melee!.MaxHp);
            Assert.Equal(8.0, melee.AggroRadius);
            Assert.Equal(16.0, melee.LeashRadius);
            Assert.Equal(15, melee.AttackDamage);
            Assert.Equal(1.5, melee.TelegraphWindupSeconds);
            Assert.True(rangedOk);
            Assert.NotNull(ranged);
            Assert.Equal(80, ranged!.MaxHp);
            Assert.Equal(10.0, ranged.AggroRadius);
            Assert.Equal(20.0, ranged.LeashRadius);
            Assert.Equal(12, ranged.AttackDamage);
            Assert.Equal(2.0, ranged.TelegraphWindupSeconds);
            Assert.True(eliteOk);
            Assert.NotNull(elite);
            Assert.Equal(200, elite!.MaxHp);
            Assert.Equal(8.0, elite.AggroRadius);
            Assert.Equal(18.0, elite.LeashRadius);
            Assert.Equal(25, elite.AttackDamage);
            Assert.Equal(2.5, elite.TelegraphWindupSeconds);
            Assert.Equal(3, list.Count);
            Assert.Equal(PrototypeNpcBehaviorRegistry.PrototypeEliteMiniBoss, list[0].Id);
            Assert.Equal(PrototypeNpcBehaviorRegistry.PrototypeRangedControl, list[^1].Id);
        }
        finally
        {
            try
            {
                Directory.Delete(root.FullName, recursive: true);
            }
            catch (IOException)
            {
                // Best-effort: transient lock or race on some hosts; temp dir is unique per run.
            }
        }
    }

    [Fact]
    public async Task Host_ShouldResolveRegistryFromDi_WhenStartupSucceeds()
    {
        // Arrange
        await using var factory = new InMemoryWebApplicationFactory();
        using var client = factory.CreateClient();
        _ = await client.GetAsync("/health");
        // Act
        var registry = factory.Services.GetRequiredService<INpcBehaviorDefinitionRegistry>();
        var meleeFound = registry.TryGetDefinition(PrototypeNpcBehaviorRegistry.PrototypeMeleePressure, out var melee);
        var unknown = registry.TryGetDefinition("not_a_real_behavior", out var missing);
        var normalized = registry.TryNormalizeKnown(" Prototype_Ranged_Control ", out var rangedId);
        var list = registry.GetDefinitionsInIdOrder();
        // Assert
        Assert.True(meleeFound);
        Assert.NotNull(melee);
        Assert.Equal(100, melee!.MaxHp);
        Assert.Equal(15, melee.AttackDamage);
        Assert.False(unknown);
        Assert.Null(missing);
        Assert.True(normalized);
        Assert.Equal(PrototypeNpcBehaviorRegistry.PrototypeRangedControl, rangedId);
        Assert.Equal(3, list.Count);
        Assert.Contains(
            list,
            b => b.Id == PrototypeNpcBehaviorRegistry.PrototypeEliteMiniBoss && b.MaxHp == 200 && b.AttackDamage == 25);
    }
}