using System.IO.Compression;
using System.Security.Cryptography;
using System.Text.Json;
using Jiaowu.Api.Domain.System;
using Jiaowu.Api.Infrastructure.Persistence;
using Jiaowu.Api.Infrastructure.Plugins;
using Jiaowu.Plugin.Abstractions;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.FileProviders;
using Microsoft.Extensions.Hosting;
using Microsoft.Extensions.Logging.Abstractions;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;

namespace Jiaowu.Api.Tests;

public sealed class PluginPackageTests
{
    [Fact]
    public void Signed_package_is_validated_and_tampering_is_rejected()
    {
        using var fixture = new PackageFixture();
        var package = fixture.CreatePackage();
        var signature = fixture.Sign(package);

        var validated = fixture.Validator.Validate(package, signature);

        Assert.Equal("sample.hello", validated.Manifest.Id);
        package[^1] ^= 0x01;
        Assert.Throws<PluginPackageException>(() =>
            fixture.Validator.Validate(package, signature));
    }

    [Fact]
    public void Package_with_incompatible_host_api_is_rejected()
    {
        using var fixture = new PackageFixture();
        var package = fixture.CreatePackage(hostApiVersion: "999");

        var exception = Assert.Throws<PluginPackageException>(() =>
            fixture.Validator.Validate(package, fixture.Sign(package)));

        Assert.Contains("Host API", exception.Message);
    }

    [Fact]
    public async Task Staged_package_can_be_marked_for_restart_activation()
    {
        using var fixture = new PackageFixture();
        var options = new DbContextOptionsBuilder<AppDbContext>()
            .UseSqlite("Data Source=:memory:")
            .Options;
        await using var db = new AppDbContext(options);
        await db.Database.OpenConnectionAsync();
        await db.Database.EnsureCreatedAsync();
        var service = new PluginPackageService(
            db,
            new BuiltInPluginCatalog(),
            fixture.Validator,
            fixture.Options,
            fixture.Environment);
        var package = fixture.CreatePackage();

        var staged = await service.StageAsync(
            package,
            fixture.Sign(package),
            "admin-user");
        var pending = await service.RequestActivationAsync(staged.Id);

        Assert.NotNull(pending);
        Assert.Equal(PluginPackageStatus.PendingActivation, pending.Status);
        Assert.Single(Directory.GetFiles(
            Path.Combine(fixture.Root, "active"),
            "*.json"));
    }

    [Fact]
    public async Task Plugin_migration_is_transactionally_recorded_once()
    {
        var options = new DbContextOptionsBuilder<AppDbContext>()
            .UseSqlite("Data Source=:memory:")
            .Options;
        await using var db = new AppDbContext(options);
        await db.Database.OpenConnectionAsync();
        await db.Database.EnsureCreatedAsync();
        var runner = new PluginMigrationRunner(
            db,
            [new TestMigration()],
            NullLogger<PluginMigrationRunner>.Instance);

        await runner.ApplyAsync();
        await runner.ApplyAsync();

        Assert.Single(await db.PluginMigrationHistory.ToListAsync());
        var tableExists = await db.Database.SqlQueryRaw<int>(
            "SELECT COUNT(*) AS Value FROM sqlite_master WHERE type = 'table' AND name = 'PluginTestData'")
            .SingleAsync();
        Assert.Equal(1, tableExists);
    }

    [Fact]
    public async Task Activated_signed_package_is_loaded_on_next_startup()
    {
        using var fixture = new PackageFixture();
        var options = new DbContextOptionsBuilder<AppDbContext>()
            .UseSqlite("Data Source=:memory:")
            .Options;
        await using var db = new AppDbContext(options);
        await db.Database.OpenConnectionAsync();
        await db.Database.EnsureCreatedAsync();
        var service = new PluginPackageService(
            db,
            new BuiltInPluginCatalog(),
            fixture.Validator,
            fixture.Options,
            fixture.Environment);
        var package = fixture.CreatePackage(useRealAssembly: true);
        var staged = await service.StageAsync(package, fixture.Sign(package), "admin");
        await service.RequestActivationAsync(staged.Id);
        var services = new ServiceCollection();

        var result = PluginStartupLoader.LoadAndConfigure(
            services,
            new ConfigurationBuilder().Build(),
            fixture.Environment,
            fixture.Options);

        var loaded = Assert.Single(result.State.Plugins);
        Assert.True(loaded.Loaded, loaded.Error);
        Assert.Equal("sample.hello", loaded.PluginId);
        Assert.Single(result.Assemblies);
    }

    private sealed class TestMigration : IPluginDatabaseMigration
    {
        public string PluginId => "sample.hello";
        public string MigrationId => "001";
        public IReadOnlyList<string> GetStatements(PluginDatabaseProvider provider) =>
            ["CREATE TABLE PluginTestData (Id TEXT NOT NULL PRIMARY KEY);"];
    }

    private sealed class PackageFixture : IDisposable
    {
        private readonly RSA rsa = RSA.Create(3072);

        public PackageFixture()
        {
            Root = Path.Combine(Path.GetTempPath(), $"jiaowu-plugin-test-{Guid.NewGuid():N}");
            Directory.CreateDirectory(Root);
            var publicKeyPath = Path.Combine(Root, "publisher.pem");
            File.WriteAllText(publicKeyPath, rsa.ExportRSAPublicKeyPem());
            Options = new PluginPlatformOptions
            {
                StoragePath = Root,
                TrustedPublishers =
                [
                    new TrustedPluginPublisher
                    {
                        Id = "school-it",
                        PublicKeyPath = publicKeyPath
                    }
                ]
            };
            Environment = new TestEnvironment { ContentRootPath = Root };
            Validator = new PluginPackageValidator(Options, Environment);
        }

        public string Root { get; }
        public PluginPlatformOptions Options { get; }
        public TestEnvironment Environment { get; }
        public PluginPackageValidator Validator { get; }

        public byte[] CreatePackage(
            string hostApiVersion = PluginHostContract.ApiVersion,
            bool useRealAssembly = false)
        {
            var manifest = new PluginManifest
            {
                Id = "sample.hello",
                Name = "示例插件",
                Description = "签名包测试",
                Version = "1.0.0",
                PublisherId = "school-it",
                HostApiVersion = hostApiVersion,
                BackendAssembly = "backend/Sample.dll",
                ModuleType = useRealAssembly
                    ? "Jiaowu.SamplePlugin.SamplePluginModule"
                    : "Sample.PluginModule",
                Capabilities = ["sample.read"]
            };
            using var buffer = new MemoryStream();
            using (var archive = new ZipArchive(buffer, ZipArchiveMode.Create, leaveOpen: true))
            {
                var manifestEntry = archive.CreateEntry("plugin.json");
                using (var writer = new StreamWriter(manifestEntry.Open()))
                    writer.Write(JsonSerializer.Serialize(manifest));
                var assemblyEntry = archive.CreateEntry("backend/Sample.dll");
                using var assembly = assemblyEntry.Open();
                if (useRealAssembly)
                {
                    var bytes = File.ReadAllBytes(
                        typeof(Jiaowu.SamplePlugin.SamplePluginModule).Assembly.Location);
                    assembly.Write(bytes);
                }
                else
                {
                    assembly.Write([0x4D, 0x5A, 0x00, 0x00]);
                }
            }
            return buffer.ToArray();
        }

        public byte[] Sign(byte[] package) => rsa.SignData(
            package,
            HashAlgorithmName.SHA256,
            RSASignaturePadding.Pss);

        public void Dispose()
        {
            rsa.Dispose();
            if (Directory.Exists(Root)) Directory.Delete(Root, recursive: true);
        }
    }

    private sealed class TestEnvironment : IHostEnvironment
    {
        public string EnvironmentName { get; set; } = Environments.Development;
        public string ApplicationName { get; set; } = "Jiaowu.Api.Tests";
        public string ContentRootPath { get; set; } = "";
        public IFileProvider ContentRootFileProvider { get; set; } =
            new NullFileProvider();
    }
}