using AcDream.App.Diagnostics;
using Xunit;

namespace AcDream.App.Tests;

public class FrameProfilerReportTests
{
    [Fact]
    public void FormatReport_IsInvariantAndComplete()
    {
        var cpu = new FrameStatsBuffer(16);
        var gpu = new FrameStatsBuffer(16);
        var alloc = new FrameStatsBuffer(16);
        var stages = new[] { new FrameStatsBuffer(16), new FrameStatsBuffer(16), new FrameStatsBuffer(16) };
        for (long i = 1; i <= 10; i++)
        {
            cpu.Push(i * 1000);      // 1..10 ms in µs
            gpu.Push(i * 100);
            alloc.Push(i * 1024);    // bytes
            stages[0].Push(i * 200);
            stages[1].Push(i * 50);
            stages[2].Push(i * 10);
        }

        string line = FrameProfiler.FormatReport(
            frameCount: 10, cpu: cpu, gpu: gpu, gpuActive: true,
            alloc: alloc, gc0: 3, gc1: 1, gc2: 0, stages: stages);

        Assert.StartsWith("[frame-prof]", line);
        Assert.Contains("n=10", line);
        Assert.Contains("cpu_ms p50=5.0 p95=10.0 p99=10.0 max=10.0", line);
        Assert.Contains("gpu_ms p50=0.5", line);
        Assert.Contains("alloc_kb p50=5.0 max=10.0", line);
        Assert.Contains("gc=3/1/0", line);
        Assert.Contains("upd p50=1.0", line);   // stage 0: 200µs·5 = 1.0 ms
    }

    [Fact]
    public void FormatReport_GpuInactive_SaysWhy()
    {
        var empty = new FrameStatsBuffer(4);
        string line = FrameProfiler.FormatReport(
            frameCount: 0, cpu: empty, gpu: empty, gpuActive: false,
            alloc: empty, gc0: 0, gc1: 0, gc2: 0,
            stages: new[] { empty, empty, empty });
        Assert.Contains("gpu=off(wbdiag)", line);
    }
}