using System;
using System.Collections.Generic;
using Paca.Mobile.Core;
using Xunit;

namespace Paca.Tests.Core;

public class NetworkLatencyJitterGateTests
{
    [Fact]
    public void Gate365_NetworkLatencyJitter_EvaluatesExcellentHealth_OnLowLatency()
    {
        var samples = new List<LatencySample>
        {
            new(15.0, true),
            new(18.0, true),
            new(16.0, true),
            new(17.0, true),
            new(15.0, true)
        };

        var report = NetworkLatencyJitterProber.AnalyzeSamples(samples);

        Assert.Equal(NetworkHealthRating.Excellent, report.Rating);
        Assert.InRange(report.AverageRttMs, 16.0, 16.5);
        Assert.True(report.JitterMs < 5.0);
        Assert.Equal(0.0, report.PacketLossPercent);
        Assert.Contains("초고속", report.Recommendation);
    }

    [Fact]
    public void Gate366_NetworkLatencyJitter_DetectsPacketLoss_AndDegradesRating()
    {
        var samples = new List<LatencySample>
        {
            new(30.0, true),
            new(0.0, false), // Lost
            new(35.0, true),
            new(40.0, true),
            new(0.0, false)  // Lost
        };

        // 2 out of 5 lost = 40% loss
        var report = NetworkLatencyJitterProber.AnalyzeSamples(samples);

        Assert.True(report.Rating == NetworkHealthRating.Degraded || report.Rating == NetworkHealthRating.Poor);
        Assert.Equal(40.0, report.PacketLossPercent);
        Assert.Contains("패킷 손실", report.Recommendation);
    }

    [Fact]
    public void Gate367_NetworkLatencyJitter_EvaluatesPoor_OnHighJitterAndLatency()
    {
        var samples = new List<LatencySample>
        {
            new(450.0, true),
            new(200.0, true),
            new(550.0, true),
            new(180.0, true)
        };

        var report = NetworkLatencyJitterProber.AnalyzeSamples(samples);

        Assert.Equal(NetworkHealthRating.Poor, report.Rating);
        Assert.True(report.AverageRttMs > 300.0);
        Assert.True(report.JitterMs > 100.0);
    }

    [Fact]
    public void Gate368_NetworkLatencyJitter_HandlesEmptyOrTotalLossGracefully()
    {
        var empty = NetworkLatencyJitterProber.AnalyzeSamples(new List<LatencySample>());
        Assert.Equal(NetworkHealthRating.Poor, empty.Rating);
        Assert.Equal(100.0, empty.PacketLossPercent);

        var totalLoss = NetworkLatencyJitterProber.AnalyzeSamples(new List<LatencySample>
        {
            new(0.0, false),
            new(0.0, false)
        });
        Assert.Equal(NetworkHealthRating.Poor, totalLoss.Rating);
        Assert.Equal(100.0, totalLoss.PacketLossPercent);
    }
}