using System.Net.Http;
using System.Net.Http.Headers;
using System.Net.Http.Json;
using VideoDownloader.Server;

namespace VideoDownloader.Tests.Server;

/// <summary>
/// E2E (M0): 실제 Kestrel 서버 기동 → 인증/페어링/큐 제어/라이브러리/스트리밍/웹 컴패니언 검증.
/// </summary>
public class RemoteServerE2ETests : IDisposable
{
    private readonly string _libDir = Path.Combine(Path.GetTempPath(), $"vd_srv_{Guid.NewGuid():N}");

    private sealed class FakeQueue : IQueueAdapter
    {
        public List<QueueItemDto> Items { get; } = new();
        public List<string> Actions { get; } = new();

        public Task<IReadOnlyList<QueueItemDto>> GetItemsAsync() => Task.FromResult<IReadOnlyList<QueueItemDto>>(Items);
        public Task<string> AddAsync(string url, string? title)
        {
            var item = new QueueItemDto(Guid.NewGuid().ToString("N"), title ?? url, url, "대기", 0);
            Items.Add(item);
            Changed?.Invoke();
            return Task.FromResult(item.Id);
        }
        public Task PauseAsync(string id) { Actions.Add($"pause:{id}"); return Task.CompletedTask; }
        public Task ResumeAsync(string id) { Actions.Add($"resume:{id}"); return Task.CompletedTask; }
        public Task CancelAsync(string id) { Actions.Add($"cancel:{id}"); return Task.CompletedTask; }

        public event Action? Changed;
    }

    [Fact]
    public async Task 서버_전_API_E2E_인증_큐_라이브러리_스트리밍_웹컴패니언()
    {
        Directory.CreateDirectory(_libDir);
        var mediaPath = Path.Combine(_libDir, "sample.mp4");
        File.WriteAllBytes(mediaPath, new byte[256 * 1024]); // 256KB 가짜 미디어

        var queue = new FakeQueue();
        await using var server = await ServerHost.StartAsync(new ServerOptions
        {
            Port = 0, // 사용 가능한 포트 자동 할당
            Token = "test-token-123",
            LibraryFolder = _libDir,
            Queue = queue,
        });

        using var http = new HttpClient { BaseAddress = new Uri($"http://127.0.0.1:{server.Port}") };

        // 1) 인증 없으면 401
        var anon = await http.GetAsync("/api/queue");
        Assert.Equal(System.Net.HttpStatusCode.Unauthorized, anon.StatusCode);

        // 2) 틀린 토큰도 401
        using var bad = new HttpRequestMessage(HttpMethod.Get, "/api/queue");
        bad.Headers.Authorization = new AuthenticationHeaderValue("Bearer", "wrong");
        Assert.Equal(System.Net.HttpStatusCode.Unauthorized, (await http.SendAsync(bad)).StatusCode);

        // 3) 페어링(올바른 토큰)
        var pair = await http.PostAsJsonAsync("/api/pair", new { token = "test-token-123", device = "E2E-Phone" });
        Assert.True(pair.IsSuccessStatusCode);

        // 4) 큐: URL 추가 → 목록 조회
        http.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", "test-token-123");
        var add = await http.PostAsJsonAsync("/api/queue", new { url = "https://x.test/v.mp4", title = "E2E 영상" });
        Assert.True(add.IsSuccessStatusCode);
        var items = await http.GetFromJsonAsync<List<QueueItemDto>>("/api/queue");
        Assert.NotNull(items);
        Assert.Single(items!);
        Assert.Equal("E2E 영상", items![0].Title);
        var id = items[0].Id;

        // 5) 큐 제어 위임
        Assert.True((await http.PostAsync($"/api/queue/{id}/pause", null)).IsSuccessStatusCode);
        Assert.True((await http.PostAsync($"/api/queue/{id}/resume", null)).IsSuccessStatusCode);
        Assert.True((await http.PostAsync($"/api/queue/{id}/cancel", null)).IsSuccessStatusCode);
        Assert.Equal(new[] { $"pause:{id}", $"resume:{id}", $"cancel:{id}" }, queue.Actions);

        // 6) 라이브러리
        var lib = await http.GetFromJsonAsync<List<LibraryItemDto>>("/api/library");
        Assert.NotNull(lib);
        Assert.Single(lib!);
        Assert.Equal("sample.mp4", lib![0].FileName);

        // 7) 스트리밍: Range 요청 → 206 부분 응답
        using var range = new HttpRequestMessage(HttpMethod.Get, $"/stream/{lib[0].Id}");
        range.Headers.Range = new System.Net.Http.Headers.RangeHeaderValue(0, 1023);
        range.Headers.Authorization = new AuthenticationHeaderValue("Bearer", "test-token-123");
        var partial = await http.SendAsync(range);
        Assert.Equal(System.Net.HttpStatusCode.PartialContent, partial.StatusCode);
        var bytes = await partial.Content.ReadAsByteArrayAsync();
        Assert.Equal(1024, bytes.Length);

        // 8) 파일 다운로드: 전체 길이
        var file = await http.GetByteArrayAsync($"/file/{lib[0].Id}");
        Assert.Equal(256 * 1024, file.Length);

        // 9) 웹 컴패니언 페이지 제공
        var page = await http.GetStringAsync("/");
        Assert.Contains("VideoDownloader", page);
        Assert.Contains("api/queue", page); // 페이지가 API 를 호출하는 스크립트 포함
    }

    public void Dispose()
    {
        try { Directory.Delete(_libDir, true); } catch { }
    }
}