using NeonSprawl.Server.Game.Factions;

namespace NeonSprawl.Server.Tests.Game.Factions;

public class FactionDefinitionCatalogLoaderTests
{
    private const string ValidPrototypeCatalogJson =
        """
        {
          "schemaVersion": 1,
          "factions": [
            {
              "id": "prototype_faction_grid_operators",
              "displayName": "Grid Operators",
              "minStanding": -100,
              "maxStanding": 100,
              "neutralStanding": 0
            },
            {
              "id": "prototype_faction_rust_collective",
              "displayName": "Rust Collective",
              "minStanding": -100,
              "maxStanding": 100,
              "neutralStanding": 0
            }
          ]
        }
        """;

    private static (string Root, string FactionsDir, string SchemaPath) CreateTempContentLayout()
    {
        var root = Directory.CreateTempSubdirectory("neon-sprawl-factioncat-");
        var factionsDir = Path.Combine(root.FullName, "content", "factions");
        var schemaDir = Path.Combine(root.FullName, "content", "schemas");
        Directory.CreateDirectory(factionsDir);
        Directory.CreateDirectory(schemaDir);
        var schemaPath = Path.Combine(schemaDir, "faction-def.schema.json");
        File.Copy(FactionCatalogTestPaths.DiscoverRepoFactionDefSchemaPath(), schemaPath, overwrite: true);
        return (root.FullName, factionsDir, schemaPath);
    }

    [Fact]
    public void Load_ShouldSucceed_WhenCatalogMatchesRepoPrototypeFile()
    {
        // Arrange
        var factionsDir = FactionCatalogTestPaths.DiscoverRepoFactionsDirectory();
        var schemaPath = FactionCatalogTestPaths.DiscoverRepoFactionDefSchemaPath();
        // Act
        var catalog = FactionDefinitionCatalogLoader.Load(factionsDir, schemaPath, NullLogger.Instance);
        // Assert
        Assert.Equal(PrototypeE7M3FactionCatalogRules.ExpectedFactionIds.Count, catalog.DistinctFactionCount);
    }

    [Fact]
    public void Load_ShouldSucceed_WhenCatalogMatchesPrototypeContract()
    {
        // Arrange
        var (_, factionsDir, schemaPath) = CreateTempContentLayout();
        File.WriteAllText(Path.Combine(factionsDir, "prototype_factions.json"), ValidPrototypeCatalogJson, Encoding.UTF8);
        // Act
        var catalog = FactionDefinitionCatalogLoader.Load(factionsDir, schemaPath, NullLogger.Instance);
        // Assert
        Assert.Equal(2, catalog.DistinctFactionCount);
        Assert.Equal(1, catalog.CatalogJsonFileCount);
        Assert.True(catalog.ById.TryGetValue("prototype_faction_grid_operators", out var grid));
        Assert.NotNull(grid);
        Assert.Equal("Grid Operators", grid!.DisplayName);
        Assert.Equal(0, grid.NeutralStanding);
    }

    [Fact]
    public void Load_ShouldThrow_WhenFactionsIsNotArray()
    {
        // Arrange
        var (_, factionsDir, schemaPath) = CreateTempContentLayout();
        File.WriteAllText(Path.Combine(factionsDir, "bad_factions.json"), """{"schemaVersion": 1, "factions": "nope"}""", Encoding.UTF8);
        // Act
        var ex = Record.Exception(() => FactionDefinitionCatalogLoader.Load(factionsDir, schemaPath, NullLogger.Instance));
        // Assert
        var ioe = Assert.IsType<InvalidOperationException>(ex);
        Assert.Contains("bad_factions.json", ioe.Message, StringComparison.Ordinal);
        Assert.Contains("expected top-level 'factions' array", ioe.Message, StringComparison.Ordinal);
    }

    [Fact]
    public void Load_ShouldThrow_WhenDuplicateIdAcrossFiles()
    {
        // Arrange
        var (_, factionsDir, schemaPath) = CreateTempContentLayout();
        const string singleFaction = """
                            {
                              "schemaVersion": 1,
                              "factions": [
                                {
                                  "id": "prototype_faction_grid_operators",
                                  "displayName": "Grid Operators",
                                  "minStanding": -100,
                                  "maxStanding": 100,
                                  "neutralStanding": 0
                                }
                              ]
                            }
                            """;
        File.WriteAllText(Path.Combine(factionsDir, "a_factions.json"), singleFaction, Encoding.UTF8);
        File.WriteAllText(Path.Combine(factionsDir, "b_factions.json"), singleFaction, Encoding.UTF8);
        // Act
        var ex = Record.Exception(() => FactionDefinitionCatalogLoader.Load(factionsDir, schemaPath, NullLogger.Instance));
        // Assert
        var ioe = Assert.IsType<InvalidOperationException>(ex);
        Assert.Contains("duplicate faction id", ioe.Message, StringComparison.Ordinal);
    }

    [Fact]
    public void Load_ShouldThrow_WhenRosterGateFails()
    {
        // Arrange
        var (_, factionsDir, schemaPath) = CreateTempContentLayout();
        const string oneFaction = """
                         {
                           "schemaVersion": 1,
                           "factions": [
                             {
                               "id": "prototype_faction_grid_operators",
                               "displayName": "Grid Operators",
                               "minStanding": -100,
                               "maxStanding": 100,
                               "neutralStanding": 0
                             }
                           ]
                         }
                         """;
        File.WriteAllText(Path.Combine(factionsDir, "prototype_factions.json"), oneFaction, Encoding.UTF8);
        // Act
        var ex = Record.Exception(() => FactionDefinitionCatalogLoader.Load(factionsDir, schemaPath, NullLogger.Instance));
        // Assert
        var ioe = Assert.IsType<InvalidOperationException>(ex);
        Assert.Contains("prototype E7M3 expects exactly faction ids", ioe.Message, StringComparison.Ordinal);
    }

    [Fact]
    public void Load_ShouldThrow_WhenFreezeTableDiverges()
    {
        // Arrange
        var (_, factionsDir, schemaPath) = CreateTempContentLayout();
        var badDisplay = ValidPrototypeCatalogJson.Replace("Grid Operators", "Wrong Name", StringComparison.Ordinal);
        File.WriteAllText(Path.Combine(factionsDir, "prototype_factions.json"), badDisplay, Encoding.UTF8);
        // Act
        var ex = Record.Exception(() => FactionDefinitionCatalogLoader.Load(factionsDir, schemaPath, NullLogger.Instance));
        // Assert
        var ioe = Assert.IsType<InvalidOperationException>(ex);
        Assert.Contains("must match E7M3 freeze table", ioe.Message, StringComparison.Ordinal);
    }

    [Fact]
    public void TryGetStandingBandGateError_ShouldReturnError_WhenOrderingFails()
    {
        // Arrange
        var rows = new Dictionary<string, FactionDefRow>(StringComparer.Ordinal)
        {
            ["prototype_faction_grid_operators"] = new(
                "prototype_faction_grid_operators",
                "Grid Operators",
                10,
                100,
                0),
        };
        // Act
        var error = PrototypeE7M3FactionCatalogRules.TryGetStandingBandGateError(rows);
        // Assert
        Assert.NotNull(error);
        Assert.Contains("requires minStanding <= neutralStanding <= maxStanding", error, StringComparison.Ordinal);
    }

    [Fact]
    public void Load_ShouldThrow_WhenStandingBandOrderingFails()
    {
        // Arrange
        var (_, factionsDir, schemaPath) = CreateTempContentLayout();
        var badBand = ValidPrototypeCatalogJson.Replace("\"minStanding\": -100", "\"minStanding\": 10", StringComparison.Ordinal);
        File.WriteAllText(Path.Combine(factionsDir, "prototype_factions.json"), badBand, Encoding.UTF8);
        // Act
        var ex = Record.Exception(() => FactionDefinitionCatalogLoader.Load(factionsDir, schemaPath, NullLogger.Instance));
        // Assert
        var ioe = Assert.IsType<InvalidOperationException>(ex);
        Assert.Contains("requires minStanding <= neutralStanding <= maxStanding", ioe.Message, StringComparison.Ordinal);
    }

    [Fact]
    public void Load_ShouldThrow_WhenFactionsDirectoryMissing()
    {
        // Arrange
        var missingDir = Path.Combine(Path.GetTempPath(), "neon-sprawl-no-factions-" + Guid.NewGuid().ToString("n"));
        var schemaPath = FactionCatalogTestPaths.DiscoverRepoFactionDefSchemaPath();
        // Act
        var ex = Record.Exception(() => FactionDefinitionCatalogLoader.Load(missingDir, schemaPath, NullLogger.Instance));
        // Assert
        var ioe = Assert.IsType<InvalidOperationException>(ex);
        Assert.Contains("missing directory", ioe.Message, StringComparison.Ordinal);
        Assert.Contains(missingDir, ioe.Message, StringComparison.Ordinal);
    }

    [Fact]
    public void Load_ShouldThrow_WhenSchemaFileMissing()
    {
        // Arrange
        var (_, factionsDir, schemaPath) = CreateTempContentLayout();
        File.Delete(schemaPath);
        // Act
        var ex = Record.Exception(() => FactionDefinitionCatalogLoader.Load(factionsDir, schemaPath, NullLogger.Instance));
        // Assert
        var ioe = Assert.IsType<InvalidOperationException>(ex);
        Assert.Contains("missing schema file", ioe.Message, StringComparison.Ordinal);
    }
}