using System;
using System.Linq;
using Paca.Mobile.Core;
using Xunit;

namespace Paca.Tests.Core;

public class AudioEqualizerProfileManagerGateTests
{
    [Fact]
    public void Gate417_AudioEqualizerProfileManager_ProvidesStandardPresets()
    {
        var bass = AudioEqualizerProfileManager.GetPreset(EqualizerPresetType.BassBoost);
        Assert.True(bass.Gains[0] > 0); // 31 Hz
        Assert.True(bass.Gains[1] > 0); // 62 Hz

        var podcast = AudioEqualizerProfileManager.GetPreset(EqualizerPresetType.PodcastVoice);
        Assert.True(podcast.Gains[0] < 0); // cut sub-bass
        Assert.True(podcast.Gains[5] > 0); // 1 kHz boost
    }

    [Fact]
    public void Gate418_AudioEqualizerProfileManager_ClampsGains_WithinSafeLimits()
    {
        var rawGains = new double[] { -30.0, 50.0, 0, 0, 0, 0, 0, 0, 0, 0 };
        var profile = AudioEqualizerProfileManager.CreateCustomProfile("Test", rawGains);

        Assert.Equal(-15.0, profile.Gains[0]);
        Assert.Equal(15.0, profile.Gains[1]);
    }

    [Fact]
    public void Gate419_AudioEqualizerProfileManager_GeneratesFfmpegEqualizerFilter_Correctly()
    {
        // Flat preset (all 0s) returns "anull"
        var flat = AudioEqualizerProfileManager.GetPreset(EqualizerPresetType.Flat);
        var flatFilter = AudioEqualizerProfileManager.BuildFfmpegFilter(flat);
        Assert.Equal("anull", flatFilter);

        // Bass boost generates equalizer filters only for non-zero bands
        var bass = AudioEqualizerProfileManager.GetPreset(EqualizerPresetType.BassBoost);
        var bassFilter = AudioEqualizerProfileManager.BuildFfmpegFilter(bass);
        Assert.Contains("equalizer=f=31:width_type=o:width=1:g=", bassFilter);
        Assert.Contains("equalizer=f=62:width_type=o:width=1:g=", bassFilter);
    }

    [Fact]
    public void Gate420_AudioEqualizerProfileManager_SerializesAndDeserializes_CustomProfileJson()
    {
        var original = AudioEqualizerProfileManager.GetPreset(EqualizerPresetType.VocalEnhance);
        var json = AudioEqualizerProfileManager.ToJson(original);
        var restored = AudioEqualizerProfileManager.FromJson(json);

        Assert.NotNull(restored);
        Assert.Equal(original.Name, restored.Name);
        Assert.Equal(original.Gains.Length, restored.Gains.Length);
        for (int i = 0; i < original.Gains.Length; i++)
        {
            Assert.Equal(original.Gains[i], restored.Gains[i], 2);
        }
    }
}