using WxAgent.Core;
using Xunit;

namespace WxAgent.Core.Tests;

public sealed class WechatStabilityTests
{
    [Fact]
    public void Deduper_HandlesTenThousandMessagesAndEvictsOldEntries()
    {
        var deduper = new BoundedMessageDeduper(2048);
        for (var index = 0; index < 10_000; index++)
            Assert.True(deduper.TryAdd($"message-{index}"));

        Assert.False(deduper.TryAdd("message-9999"));
        Assert.True(deduper.TryAdd("message-0"));
    }

    [Theory]
    [InlineData("Qt51514QWindowIcon", "微信", true)]
    [InlineData("Qt6QWindowIcon", "微信", true)]
    [InlineData("Qt51514QWindowIcon", "文件传输助手", false)]
    [InlineData("Qt51514WxTrayIconMessageWindowClass", "微信", false)]
    [InlineData("Notepad", "微信", false)]
    public void NativeWindowMatching_RejectsSubwindowsAndOtherApplications(string className, string title, bool expected)
    {
        Assert.Equal(expected, WechatLocators.IsNativeMainWindow(className, title));
    }

    [Theory]
    [InlineData("微信", true)]
    [InlineData("微信\n收到新消息", true)]
    [InlineData("WeChat", true)]
    [InlineData("企业微信", false)]
    [InlineData("微信测试脚本", false)]
    public void TrayMatching_IsExplicit(string name, bool expected) =>
        Assert.Equal(expected, WechatLocators.IsWechatTrayName(name));

    [Fact]
    public void StabilityAnalyzer_DetectsAgentLeakAndFinalError()
    {
        var now = DateTimeOffset.UtcNow;
        var first = Sample(now, 100, 10, 1);
        var last = first with { Timestamp = now.AddHours(1), AgentHandleCount = 101, Errors = [WxAgentErrorCode.SessionLocked] };
        var report = WechatStabilityAnalyzer.Analyze(now, last.Timestamp, [first, last], 0, 0);
        Assert.False(report.Healthy);
        Assert.Contains("agent-handle-growth-over-100", report.Findings);
        Assert.Contains("final-error:SessionLocked", report.Findings);
    }

    [Fact]
    public void Deduper_RejectsInvalidCapacity()
    {
        Assert.Throws<ArgumentOutOfRangeException>(() => new BoundedMessageDeduper(0));
    }

    [Fact]
    public void StabilityAnalyzer_ReportsHealthyBoundedGrowth()
    {
        var started = DateTimeOffset.UtcNow;
        var samples = new[]
        {
            Sample(started, 100_000_000, 100, 20),
            Sample(started.AddMinutes(1), 110_000_000, 120, 22)
        };

        var report = WechatStabilityAnalyzer.Analyze(started, started.AddMinutes(1), samples, 5, 1);

        Assert.True(report.Healthy);
        Assert.Equal(10_000_000, report.WorkingSetGrowthBytes);
        Assert.Empty(report.Findings);
    }

    [Fact]
    public void StabilityAnalyzer_AllowsTransientWindowLossAfterReconnect()
    {
        var started = DateTimeOffset.UtcNow;
        var samples = new[]
        {
            Sample(started, 100_000_000, 100, 20),
            Sample(started.AddMinutes(1), 0, 0, 0, windowFound: false),
            Sample(started.AddMinutes(2), 105_000_000, 110, 21)
        };

        var report = WechatStabilityAnalyzer.Analyze(started, started.AddMinutes(2), samples, 0, 1);

        Assert.True(report.Healthy);
        Assert.DoesNotContain("wechat-window-unavailable", report.Findings);
    }

    [Fact]
    public void StabilityAnalyzer_FlagsWindowLossAndResourceGrowth()
    {
        var started = DateTimeOffset.UtcNow;
        var samples = new[]
        {
            Sample(started, 100_000_000, 100, 20),
            Sample(started.AddHours(1), 400_000_000, 700, 150, windowFound: false)
        };

        var report = WechatStabilityAnalyzer.Analyze(started, started.AddHours(1), samples, 0, 0);

        Assert.False(report.Healthy);
        Assert.Contains("wechat-window-unavailable", report.Findings);
        Assert.Contains("working-set-growth-over-256mb", report.Findings);
        Assert.Contains("handle-growth-over-500", report.Findings);
        Assert.Contains("thread-growth-over-100", report.Findings);
    }

    [Theory]
    [InlineData(30, false, 0, true)]
    [InlineData(15, false, 0, false)]
    [InlineData(30, true, 0, false)]
    [InlineData(30, false, 11, false)]
    public void RunChecks_ApplyDurationCancellationAndHeartbeatToEveryReport(int seconds, bool cancelled, int snapshotAge, bool healthy)
    {
        var finish = DateTimeOffset.UtcNow;
        var last = Sample(finish, 100, 10, 1) with { LastSnapshotAt = finish.AddSeconds(-snapshotAge) };
        var report = WechatStabilityAnalyzer.Analyze(finish.AddSeconds(-seconds), finish, [last], 0, 0);
        var checkedReport = WechatStabilityAnalyzer.CheckRun(report, TimeSpan.FromSeconds(30), TimeSpan.FromSeconds(seconds), cancelled);
        Assert.Equal(healthy, checkedReport.Healthy);
        Assert.Equal(seconds >= 29 && !cancelled, checkedReport.CompletedDuration);
    }

    [Fact]
    public void RunChecks_RejectMissingHeartbeatAndBackgroundFailures()
    {
        var finish = DateTimeOffset.UtcNow;
        var report = WechatStabilityAnalyzer.Analyze(finish.AddHours(-8), finish, [Sample(finish, 0, 0, 0)], 0, 0);
        report = WechatStabilityAnalyzer.CheckRun(report, TimeSpan.FromHours(8), TimeSpan.FromHours(8), false,
            "InvalidOperationException", "IOException");
        Assert.False(report.Healthy);
        Assert.Contains("listener-snapshot-stale", report.Findings);
        Assert.Contains("listener-failed:InvalidOperationException", report.Findings);
        Assert.Contains("sampling-failed:IOException", report.Findings);
    }

    [Fact]
    public void StabilityAnalyzer_DoesNotHideMissingHeartbeatBeforeRecovery()
    {
        var started = DateTimeOffset.UtcNow;
        var missing = Sample(started.AddMinutes(6), 100, 10, 1);
        var recovered = missing with { Timestamp = started.AddMinutes(7), LastSnapshotAt = started.AddMinutes(7) };
        var report = WechatStabilityAnalyzer.Analyze(started, recovered.Timestamp, [missing, recovered], 0, 1);
        Assert.Contains("listener-snapshot-gap-over-5min", report.Findings);
        Assert.False(report.Healthy);
    }

    [Fact]
    public async Task ReportWrite_PreservesExistingEvidenceWhenCancelled()
    {
        var directory = Path.Combine(Path.GetTempPath(), "wx-stability-" + Guid.NewGuid());
        Directory.CreateDirectory(directory);
        try
        {
            var path = Path.Combine(directory, "report.json");
            await File.WriteAllTextAsync(path, "previous evidence");
            var now = DateTimeOffset.UtcNow;
            var report = WechatStabilityAnalyzer.Analyze(now, now, [Sample(now, 0, 0, 0)], 0, 0);
            using var cancelled = new CancellationTokenSource();
            cancelled.Cancel();
            await Assert.ThrowsAnyAsync<OperationCanceledException>(() =>
                WechatStabilityAnalyzer.WriteJsonAsync(report, path, cancelled.Token));
            Assert.Equal("previous evidence", await File.ReadAllTextAsync(path));
            Assert.False(File.Exists(path + ".tmp"));
        }
        finally { Directory.Delete(directory, recursive: true); }
    }

    [Theory]
    [InlineData("Shell_TrayWnd", true)]
    [InlineData("Shell_SecondaryTrayWnd", true)]
    [InlineData("NotifyIconOverflowWindow", true)]
    [InlineData("Qt51514QWindowIcon", false)]
    [InlineData("Chrome_WidgetWin_1", false)]
    [InlineData("", false)]
    public void TrayClicks_RequireANotificationAreaHitTarget(string className, bool expected)
    {
        Assert.Equal(expected, WechatLocators.IsNotificationAreaRoot(className));
    }

    private static WechatStabilitySample Sample(
        DateTimeOffset timestamp,
        long memory,
        int handles,
        int threads,
        bool windowFound = true) =>
        new(timestamp, 1, memory, handles, threads, windowFound, [], 0, 0);
}