using System.Net;
using System.Text.Json.Nodes;
using MoShiro.Protocol;
using MoShiro.TestSupport;

namespace MoShiro.Backend.Tests;

[Collection("probe-e2e")]
public sealed class UpdateTests
{
    private const string Digest = "sha256:0123456789abcdef0123456789abcdef0123456789abcdef0123456789abcdef";

    // 每个用例取自己的 seq（单调递增）：共用的后端只接受比已登记的更大的 seq，用例的先后顺序不能影响结果
    private static long s_seq = TimeProvider.System.GetUtcNow().ToUnixTimeSeconds() * 1000;

    private static long NextSeq() => Interlocked.Add(ref s_seq, 100);

    private readonly BackendFixture _backend;

    public UpdateTests(BackendFixture backend)
    {
        _backend = backend;
    }

    // 面板验发布签名（节点宿主机上的更新器之后还会再验）：测试后端换成了测试密钥，清单用同一把签
    private static string Manifest(string component, long seq, string digest = Digest) =>
        $$"""{"schema":1,"component":"{{component}}","channel":"dev","image":"registry.example/moshiro-dev/moshiro-{{component}}","digest":"{{digest}}","tag":"dev-{{seq}}","version":"0.1.1","commit":"abc","built_at":"2026-10-06T00:00:00Z","seq":{{seq}}}""";

    private async Task<HttpResponseMessage> PublishAsync(string manifest, string? signature = null)
    {
        signature ??= TestReleaseKey.Sign(manifest);
        return await _backend.Anonymous.PostAsync("/api/release/offer", BackendFixture.Json(new JsonObject { ["manifest"] = manifest, ["signature"] = signature }));
    }

    [Fact]
    public async Task Release_IsForwardedByteForByte_ToOnlineNodesOfThatComponent_AndToNodesThatConnectLater()
    {
        long seq = NextSeq();
        await using AgentSimulator online = await _backend.ConnectAgentAsync();
        string manifest = Manifest("agent", seq);
        string signature = TestReleaseKey.Sign(manifest); // ECDSA 每次签出来都不一样：签一次，登记和比较共用

        using HttpResponseMessage published = await PublishAsync(manifest, signature);
        Assert.Equal(HttpStatusCode.Created, published.StatusCode);
        JsonNode release = JsonNode.Parse(await published.Content.ReadAsStringAsync())!;
        Assert.Equal("agent", release["component"]!.GetValue<string>());
        Assert.Equal(Digest, release["digest"]!.GetValue<string>());

        await BackendFixture.EventuallyAsync(() => Task.FromResult(online.UpdateOffers.ToArray().Any(o => o.Manifest == manifest && o.Signature == signature)), because: "the offer reaches online agents unchanged");

        // 之后才连上的节点，hello 之后补发
        await using AgentSimulator late = await _backend.ConnectAgentAsync();
        await BackendFixture.EventuallyAsync(() => Task.FromResult(late.UpdateOffers.ToArray().Any(o => o.Manifest == manifest)), because: "a node that connects later still gets the latest offer");

        // 另一个组件（probe）的清单不会发给 Agent
        using HttpResponseMessage probeRelease = await PublishAsync(Manifest("probe", seq));
        Assert.Equal(HttpStatusCode.Created, probeRelease.StatusCode);
        await Task.Delay(300);
        Assert.DoesNotContain(online.UpdateOffers.ToArray(), o => o.Manifest.Contains("\"component\":\"probe\"", StringComparison.Ordinal));
    }

    [Fact]
    public async Task Release_Registration_RefusesBadManifests_BadSignatures_AndStaleSeq()
    {
        long seq = NextSeq();
        Assert.Equal(HttpStatusCode.BadRequest, (await PublishAsync("{not json")).StatusCode);
        Assert.Equal(HttpStatusCode.BadRequest, (await PublishAsync(Manifest("agent", seq, digest: "sha256:short"))).StatusCode);
        Assert.Equal(HttpStatusCode.BadRequest, (await PublishAsync(Manifest("unknown", seq))).StatusCode);
        Assert.Equal(HttpStatusCode.Forbidden, (await PublishAsync(Manifest("agent", seq), signature: "not base64!")).StatusCode);

        using var other = System.Security.Cryptography.ECDsa.Create(System.Security.Cryptography.ECCurve.NamedCurves.nistP256);
        string foreign = Convert.ToBase64String(other.SignData(System.Text.Encoding.UTF8.GetBytes(Manifest("agent", seq)), System.Security.Cryptography.HashAlgorithmName.SHA256, System.Security.Cryptography.DSASignatureFormat.Rfc3279DerSequence));
        Assert.Equal(HttpStatusCode.Forbidden, (await PublishAsync(Manifest("agent", seq), foreign)).StatusCode); // 别人的密钥签的
        Assert.Equal(HttpStatusCode.Forbidden, (await PublishAsync(Manifest("agent", seq), "MEUCIQDc")).StatusCode); // 格式对、签名不对
        Assert.Equal(HttpStatusCode.Forbidden, (await PublishAsync(Manifest("agent", seq), TestReleaseKey.Sign(Manifest("agent", seq + 5)))).StatusCode); // 签的是另一份清单
        Assert.Equal(HttpStatusCode.Created, (await PublishAsync(Manifest("agent", seq))).StatusCode);
        Assert.Equal(HttpStatusCode.Conflict, (await PublishAsync(Manifest("agent", seq))).StatusCode); // 同一个 seq：重放
        Assert.Equal(HttpStatusCode.Conflict, (await PublishAsync(Manifest("agent", seq - 1))).StatusCode); // 更旧的 seq
    }

    [Fact]
    public async Task UpdateRequest_ReachesTheNode_AndItsReportedStatusShowsInBuildInfo()
    {
        await using AgentSimulator agent = await _backend.ConnectAgentAsync();
        using HttpResponseMessage request = await _backend.Admin.PostAsync($"/api/admin/nodes/{agent.NodeId.Value}/update", null);
        Assert.Equal(HttpStatusCode.NoContent, request.StatusCode);
        await BackendFixture.EventuallyAsync(() => Task.FromResult(agent.UpdateApplies == 1));

        // 节点（宿主机更新器）报告状态：面板在构建信息里显示
        await agent.SendUpdateStatusAsync(new UpdateStatus { State = "available", Available = new UpdateAvailable { Tag = "dev-9", Version = "0.1.1", Digest = Digest, Seq = 9 }, At = TimeProvider.System.GetUtcNow().ToUnixTimeSeconds() });
        await BackendFixture.EventuallyAsync(async () =>
        {
            JsonNode info = await _backend.GetJsonAsync(_backend.Admin, "/api/admin/build-info");
            JsonNode? node = info["nodes"]!.AsArray().FirstOrDefault(n => n!["id"]!.GetValue<string>() == agent.NodeId.Value);
            return node?["update"]?["state"]?.GetValue<string>() == "available" && node["update"]!["available_tag"]!.GetValue<string>() == "dev-9";
        }, because: "the update state comes from the node's heartbeat");

        // 节点离线之后不能请求更新
        string id = agent.NodeId.Value;
        await agent.DisposeAsync();
        await BackendFixture.EventuallyAsync(async () =>
        {
            using HttpResponseMessage offline = await _backend.Admin.PostAsync($"/api/admin/nodes/{id}/update", null);
            return offline.StatusCode == HttpStatusCode.Conflict || offline.StatusCode == HttpStatusCode.NotFound;
        });
    }
}