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

namespace Paca.Tests.Mobile;

/// <summary>
/// Gate 147 ~ 150: 모바일 오프라인 미디어 라이브러리 & 스토리지 대시보드 기계적 검증
/// </summary>
public class MobileOfflineLibraryDashboardGateTests
{
    [Fact]
    public void Gate147_OfflineMediaItem_DisplayFormatting()
    {
        var item1 = new OfflineMediaItem(
            Id: "media-1",
            FileName: "RickRoll_4K.mp4",
            SizeBytes: 104_857_600L, // 100 MB
            LocalFilePath: "/data/user/0/com.paca.mobile/files/RickRoll_4K.mp4",
            DownloadedAt: DateTimeOffset.UtcNow,
            IsIntegrityVerified: true
        );

        Assert.Equal("100.0 MB", item1.DisplaySize);
        Assert.True(item1.IsIntegrityVerified);

        var item2 = new OfflineMediaItem(
            Id: "media-2",
            FileName: "LongVideo_HDR.mkv",
            SizeBytes: 1_610_612_736L, // 1.5 GB
            LocalFilePath: "/data/user/0/com.paca.mobile/files/LongVideo_HDR.mkv",
            DownloadedAt: DateTimeOffset.UtcNow,
            IsIntegrityVerified: true
        );

        Assert.Equal("1.5 GB", item2.DisplaySize);
    }

    [Fact]
    public void Gate148_LocalStorageDashboard_Calculates_Usage_Percentages()
    {
        // 총 128 GB (137,438,953,472 B), 남은 용량 64 GB, Paca 사용 6.4 GB (5%)
        long totalStorage = 128L * 1024 * 1024 * 1024;
        long freeStorage = 64L * 1024 * 1024 * 1024;
        long pacaStorage = (long)(totalStorage * 0.05); // 5%

        var dashboard = LocalStorageDashboard.Calculate(totalStorage, freeStorage, pacaStorage);

        Assert.Equal(5.0, Math.Round(dashboard.PacaUsagePercent, 1));
        Assert.Equal(50.0, Math.Round(dashboard.FreePercent, 1));
        Assert.Contains("Paca", dashboard.StorageSummaryText);
        Assert.Contains("여유", dashboard.StorageSummaryText);
    }

    [Fact]
    public void Gate149_OfflineLibraryManager_Filtering_And_Sorting()
    {
        var manager = new OfflineLibraryManager();

        manager.RegisterMedia(new OfflineMediaItem("id-1", "Alpha.mp4", 50_000_000, "/path/1", DateTimeOffset.UtcNow.AddHours(-2), true));
        manager.RegisterMedia(new OfflineMediaItem("id-2", "Beta.mp3", 10_000_000, "/path/2", DateTimeOffset.UtcNow.AddHours(-1), true));
        manager.RegisterMedia(new OfflineMediaItem("id-3", "Gamma.mp4", 200_000_000, "/path/3", DateTimeOffset.UtcNow, true));

        // 1. 최신순 정렬 검증 (Gamma -> Beta -> Alpha)
        var recentList = manager.GetItems(MediaFilter.All, MediaSortOrder.NewestFirst);
        Assert.Equal(3, recentList.Count);
        Assert.Equal("Gamma.mp4", recentList[0].FileName);
        Assert.Equal("Beta.mp3", recentList[1].FileName);
        Assert.Equal("Alpha.mp4", recentList[2].FileName);

        // 2. 용량 큰 순 정렬 검증 (Gamma(200MB) -> Alpha(50MB) -> Beta(10MB))
        var sizeList = manager.GetItems(MediaFilter.All, MediaSortOrder.LargestFirst);
        Assert.Equal("Gamma.mp4", sizeList[0].FileName);
        Assert.Equal("Alpha.mp4", sizeList[1].FileName);
        Assert.Equal("Beta.mp3", sizeList[2].FileName);

        // 3. 오디오만 필터링 검증
        var audioList = manager.GetItems(MediaFilter.AudioOnly, MediaSortOrder.NewestFirst);
        Assert.Single(audioList);
        Assert.Equal("Beta.mp3", audioList[0].FileName);

        // 4. 비디오만 필터링 검증
        var videoList = manager.GetItems(MediaFilter.VideoOnly, MediaSortOrder.NewestFirst);
        Assert.Equal(2, videoList.Count);
        Assert.DoesNotContain(videoList, x => x.FileName.EndsWith(".mp3"));
    }

    [Fact]
    public void Gate150_OfflineLibraryManager_Deletion_Updates_Quota()
    {
        var manager = new OfflineLibraryManager();
        manager.RegisterMedia(new OfflineMediaItem("id-1", "Video1.mp4", 100_000_000, "/path/1", DateTimeOffset.UtcNow, true));
        manager.RegisterMedia(new OfflineMediaItem("id-2", "Video2.mp4", 50_000_000, "/path/2", DateTimeOffset.UtcNow, true));

        Assert.Equal(150_000_000L, manager.TotalPacaBytes);

        // id-1 삭제
        var removed = manager.RemoveMedia("id-1");
        Assert.True(removed);
        Assert.Equal(50_000_000L, manager.TotalPacaBytes);
        Assert.Single(manager.GetItems(MediaFilter.All, MediaSortOrder.NewestFirst));
    }
}