using System.Net;
using System.Text.Json.Nodes;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting.Server;
using Microsoft.AspNetCore.Hosting.Server.Features;
using Microsoft.Extensions.DependencyInjection;
using MoShiro.Backend.Application;

namespace MoShiro.Backend.Tests;

/// <summary>
/// 首次认领：面板里没有任何用户时，部署的人自己填管理员的用户名和密码——没有默认账户、没有默认密码。
/// 谁先打开页面谁就能当管理员，所以要有只有部署的人才拿得到的认领码（写在后端日志里，或者部署时指定）；创建完第一个管理员，入口就关了。
/// </summary>
public sealed class SetupTests : IAsyncLifetime
{
    private const string Code = "ABCD-EFGH-JKLM-NPQR";

    private WebApplication _app = null!;
    private HttpClient _http = null!;
    private string _directory = "";

    public async ValueTask InitializeAsync()
    {
        _directory = Path.Combine(Path.GetTempPath(), "moshiro-setup-" + Guid.NewGuid().ToString("N"));
        _app = BackendHost.Build(
            ["--urls", "http://127.0.0.1:0", "--Logging:LogLevel:Default=Warning"],
            options =>
            {
                options.DataDirectory = _directory;
                options.Pbkdf2Iterations = 1000;
                options.SecureCookies = false;
                options.ClaimCode = Code;
                options.LoginAttemptsPerMinute = 1000;
                options.GeoLookupUrl = string.Empty;
            });
        await _app.StartAsync();
        _http = new HttpClient { BaseAddress = new Uri(_app.Services.GetRequiredService<IServer>().Features.Get<IServerAddressesFeature>()!.Addresses.First()) };
    }

    public async ValueTask DisposeAsync()
    {
        _http.Dispose();
        await _app.StopAsync();
        await _app.DisposeAsync();
        Microsoft.Data.Sqlite.SqliteConnection.ClearAllPools(); // 连接池还拿着数据库文件
        TryDelete(_directory);
    }

    /// <summary>临时目录：尽力删除。SQLite 的 WAL 临时文件可能还没释放，留下一个临时目录比让测试失败好。</summary>
    private static void TryDelete(string directory)
    {
        try
        {
            Directory.Delete(directory, recursive: true);
        }
        catch (IOException)
        {
            // 系统临时目录里的残留，会被清理
        }
    }

    private Task<HttpResponseMessage> SetupAsync(string? code, string username, string password, bool returnSession = false) =>
        _http.PostAsync("/api/admin/auth/setup", BackendFixture.Json(new JsonObject { ["claim_code"] = code, ["username"] = username, ["password"] = password, ["return_session"] = returnSession }));

    [Fact]
    public async Task ABrandNewPanel_HasNoUsers_AndNoDefaultAccountToSignInWith()
    {
        JsonNode status = JsonNode.Parse(await _http.GetStringAsync("/api/admin/auth/setup"))!;
        Assert.True(status["needs_setup"]!.GetValue<bool>());

        foreach (string username in new[] { "admin", "administrator", "root" })
        {
            using HttpResponseMessage login = await _http.PostAsync("/api/admin/auth/login", BackendFixture.Json(new JsonObject { ["username"] = username, ["password"] = "admin" }));
            Assert.Equal(HttpStatusCode.Unauthorized, login.StatusCode);
        }
    }

    [Fact]
    public async Task TheClaimCode_IsRequired_SoTheFirstVisitorCannotTakeThePanel()
    {
        using HttpResponseMessage none = await SetupAsync(null, "owner", "correct horse battery");
        using HttpResponseMessage wrong = await SetupAsync("AAAA-BBBB-CCCC-DDDD", "owner", "correct horse battery");
        using HttpResponseMessage empty = await SetupAsync("", "owner", "correct horse battery");

        Assert.Equal(HttpStatusCode.Unauthorized, none.StatusCode);
        Assert.Equal(HttpStatusCode.Unauthorized, wrong.StatusCode);
        Assert.Equal(HttpStatusCode.Unauthorized, empty.StatusCode);
        Assert.True(JsonNode.Parse(await _http.GetStringAsync("/api/admin/auth/setup"))!["needs_setup"]!.GetValue<bool>()); // 还是没人
    }

    [Fact]
    public async Task TheCredentialsAreValidated_AndAMistakeDoesNotBurnTheCode()
    {
        using HttpResponseMessage shortPassword = await SetupAsync(Code, "owner", "short");
        using HttpResponseMessage badName = await SetupAsync(Code, "x", "correct horse battery");

        Assert.Equal(HttpStatusCode.BadRequest, shortPassword.StatusCode);
        Assert.Equal(HttpStatusCode.BadRequest, badName.StatusCode);

        // 填错了还能再来
        using HttpResponseMessage ok = await SetupAsync(Code, "owner", "correct horse battery");
        Assert.Equal(HttpStatusCode.Created, ok.StatusCode);
    }

    [Fact]
    public async Task TheFirstAdministrator_IsCreatedByTheDeployer_SignedInRightAway_AndTheDoorCloses()
    {
        // 认领码不分大小写、不看分隔符
        using HttpResponseMessage created = await SetupAsync("abcd efgh-jklm npqr", "owner", "correct horse battery", returnSession: true);

        Assert.Equal(HttpStatusCode.Created, created.StatusCode);
        JsonNode body = JsonNode.Parse(await created.Content.ReadAsStringAsync())!;
        Assert.Equal("owner", body["username"]!.GetValue<string>());
        Assert.False(string.IsNullOrEmpty(body["session_token"]?.GetValue<string>())); // 马上登录，接着引导 passkey 和信任根

        // 入口关了：再用同一个码、别的用户名也不行，状态也变了
        using HttpResponseMessage again = await SetupAsync(Code, "intruder", "correct horse battery");
        Assert.Equal(HttpStatusCode.Conflict, again.StatusCode);
        Assert.False(JsonNode.Parse(await _http.GetStringAsync("/api/admin/auth/setup"))!["needs_setup"]!.GetValue<bool>());

        // 管理员能用自己填的账号密码正常登录（密码登录的会话有能力，passkey 之后再加）
        using HttpResponseMessage login = await _http.PostAsync("/api/admin/auth/login", BackendFixture.Json(new JsonObject { ["username"] = "owner", ["password"] = "correct horse battery" }));
        Assert.Equal(HttpStatusCode.OK, login.StatusCode);
    }

    [Fact]
    public async Task WithoutAConfiguredCode_TheBackendGeneratesOne_AndNothingElseUnlocksTheSetup()
    {
        // 另起一个没有指定认领码的后端：随机生成并写进日志，猜不到；任何别的码都进不去
        string directory = Path.Combine(Path.GetTempPath(), "moshiro-setup-" + Guid.NewGuid().ToString("N"));
        await using WebApplication generated = BackendHost.Build(
            ["--urls", "http://127.0.0.1:0", "--Logging:LogLevel:Default=Warning"],
            options =>
            {
                options.DataDirectory = directory;
                options.Pbkdf2Iterations = 1000;
                options.SecureCookies = false;
                options.LoginAttemptsPerMinute = 1000;
                options.GeoLookupUrl = string.Empty;
            });
        await generated.StartAsync();
        try
        {
            using var http = new HttpClient { BaseAddress = new Uri(generated.Services.GetRequiredService<IServer>().Features.Get<IServerAddressesFeature>()!.Addresses.First()) };
            foreach (string guess in new[] { Code, "0000-0000-0000-0000", "admin", "TEST-CLAIM-CODE-0001" })
            {
                using HttpResponseMessage response = await http.PostAsync("/api/admin/auth/setup", BackendFixture.Json(new JsonObject { ["claim_code"] = guess, ["username"] = "owner", ["password"] = "correct horse battery" }));
                Assert.Equal(HttpStatusCode.Unauthorized, response.StatusCode);
            }

            Assert.True(JsonNode.Parse(await http.GetStringAsync("/api/admin/auth/setup"))!["needs_setup"]!.GetValue<bool>());
        }
        finally
        {
            await generated.StopAsync();
            await generated.DisposeAsync();
            Microsoft.Data.Sqlite.SqliteConnection.ClearAllPools();
            TryDelete(directory);
        }
    }
}