using System.Collections.Generic;
using System.Data.Common;
using System.IO;
using System.IO.Abstractions.TestingHelpers;
using System.Linq;
using System.Threading.Tasks;
using API.Data;
using API.Data.Metadata;
using API.Entities;
using API.Entities.Enums;
using API.Parser;
using API.Services;
using API.SignalR;
using AutoMapper;
using Microsoft.AspNetCore.SignalR;
using Microsoft.Data.Sqlite;
using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.Infrastructure;
using Microsoft.Extensions.Logging;
using NSubstitute;
using Xunit;

namespace API.Tests.Services
{
    internal class MockReadingItemServiceForCacheService : IReadingItemService
    {
        private readonly DirectoryService _directoryService;

        public MockReadingItemServiceForCacheService(DirectoryService directoryService)
        {
            _directoryService = directoryService;
        }

        public ComicInfo GetComicInfo(string filePath)
        {
            return null;
        }

        public int GetNumberOfPages(string filePath, MangaFormat format)
        {
            return 1;
        }

        public string GetCoverImage(string fileFilePath, string fileName, MangaFormat format)
        {
            return string.Empty;
        }

        public void Extract(string fileFilePath, string targetDirectory, MangaFormat format, int imageCount = 1)
        {
            throw new System.NotImplementedException();
        }

        public ParserInfo Parse(string path, string rootPath, LibraryType type)
        {
            throw new System.NotImplementedException();
        }
    }
    public class CacheServiceTests
    {
        private readonly ILogger<CacheService> _logger = Substitute.For<ILogger<CacheService>>();
        private readonly IUnitOfWork _unitOfWork;
        private readonly IHubContext<MessageHub> _messageHub = Substitute.For<IHubContext<MessageHub>>();

        private readonly DbConnection _connection;
        private readonly DataContext _context;

        private const string CacheDirectory = "C:/kavita/config/cache/";
        private const string CoverImageDirectory = "C:/kavita/config/covers/";
        private const string BackupDirectory = "C:/kavita/config/backups/";
        private const string DataDirectory = "C:/data/";

        public CacheServiceTests()
        {
            var contextOptions = new DbContextOptionsBuilder()
                .UseSqlite(CreateInMemoryDatabase())
                .Options;
            _connection = RelationalOptionsExtension.Extract(contextOptions).Connection;

            _context = new DataContext(contextOptions);
            Task.Run(SeedDb).GetAwaiter().GetResult();

            _unitOfWork = new UnitOfWork(_context, Substitute.For<IMapper>(), null);
        }

        #region Setup

        private static DbConnection CreateInMemoryDatabase()
        {
            var connection = new SqliteConnection("Filename=:memory:");

            connection.Open();

            return connection;
        }

        public void Dispose() => _connection.Dispose();

        private async Task<bool> SeedDb()
        {
            await _context.Database.MigrateAsync();
            var filesystem = CreateFileSystem();

            await Seed.SeedSettings(_context, new DirectoryService(Substitute.For<ILogger<DirectoryService>>(), filesystem));

            var setting = await _context.ServerSetting.Where(s => s.Key == ServerSettingKey.CacheDirectory).SingleAsync();
            setting.Value = CacheDirectory;

            setting = await _context.ServerSetting.Where(s => s.Key == ServerSettingKey.BackupDirectory).SingleAsync();
            setting.Value = BackupDirectory;

            _context.ServerSetting.Update(setting);

            _context.Library.Add(new Library()
            {
                Name = "Manga",
                Folders = new List<FolderPath>()
                {
                    new FolderPath()
                    {
                        Path = "C:/data/"
                    }
                }
            });
            return await _context.SaveChangesAsync() > 0;
        }

        private async Task ResetDB()
        {
            _context.Series.RemoveRange(_context.Series.ToList());

            await _context.SaveChangesAsync();
        }

        private static MockFileSystem CreateFileSystem()
        {
            var fileSystem = new MockFileSystem();
            fileSystem.Directory.SetCurrentDirectory("C:/kavita/");
            fileSystem.AddDirectory("C:/kavita/config/");
            fileSystem.AddDirectory(CacheDirectory);
            fileSystem.AddDirectory(CoverImageDirectory);
            fileSystem.AddDirectory(BackupDirectory);
            fileSystem.AddDirectory(DataDirectory);

            return fileSystem;
        }

        #endregion

        #region Ensure

        [Fact]
        public async Task Ensure_DirectoryAlreadyExists_DontExtractAnything()
        {
            var filesystem = CreateFileSystem();
            filesystem.AddFile($"{DataDirectory}Test v1.zip", new MockFileData(""));
            filesystem.AddDirectory($"{CacheDirectory}1/");
            var ds = new DirectoryService(Substitute.For<ILogger<DirectoryService>>(), filesystem);
            var cleanupService = new CacheService(_logger, _unitOfWork, ds,
                new ReadingItemService(Substitute.For<IArchiveService>(),
                    Substitute.For<IBookService>(), Substitute.For<IImageService>(), ds), Substitute.For<IBookmarkService>());

            await ResetDB();
            var s = DbFactory.Series("Test");
            var v = DbFactory.Volume("1");
            var c = new Chapter()
            {
                Number = "1",
                Files = new List<MangaFile>()
                {
                    new MangaFile()
                    {
                        Format = MangaFormat.Archive,
                        FilePath = $"{DataDirectory}Test v1.zip",
                    }
                }
            };
            v.Chapters.Add(c);
            s.Volumes.Add(v);
            s.LibraryId = 1;
            _context.Series.Add(s);

            await _context.SaveChangesAsync();

            await cleanupService.Ensure(1);
            Assert.Empty(ds.GetFiles(filesystem.Path.Join(CacheDirectory, "1"), searchOption:SearchOption.AllDirectories));
        }

        // [Fact]
        // public async Task Ensure_DirectoryAlreadyExists_ExtractsImages()
        // {
        //     // TODO: Figure out a way to test this
        //     var filesystem = CreateFileSystem();
        //     filesystem.AddFile($"{DataDirectory}Test v1.zip", new MockFileData(""));
        //     filesystem.AddDirectory($"{CacheDirectory}1/");
        //     var ds = new DirectoryService(Substitute.For<ILogger<DirectoryService>>(), filesystem);
        //     var archiveService = Substitute.For<IArchiveService>();
        //     archiveService.ExtractArchive($"{DataDirectory}Test v1.zip",
        //         filesystem.Path.Join(CacheDirectory, "1"));
        //     var cleanupService = new CacheService(_logger, _unitOfWork, ds,
        //         new ReadingItemService(archiveService, Substitute.For<IBookService>(), Substitute.For<IImageService>(), ds));
        //
        //     await ResetDB();
        //     var s = DbFactory.Series("Test");
        //     var v = DbFactory.Volume("1");
        //     var c = new Chapter()
        //     {
        //         Number = "1",
        //         Files = new List<MangaFile>()
        //         {
        //             new MangaFile()
        //             {
        //                 Format = MangaFormat.Archive,
        //                 FilePath = $"{DataDirectory}Test v1.zip",
        //             }
        //         }
        //     };
        //     v.Chapters.Add(c);
        //     s.Volumes.Add(v);
        //     s.LibraryId = 1;
        //     _context.Series.Add(s);
        //
        //     await _context.SaveChangesAsync();
        //
        //     await cleanupService.Ensure(1);
        //     Assert.Empty(ds.GetFiles(filesystem.Path.Join(CacheDirectory, "1"), searchOption:SearchOption.AllDirectories));
        // }


        #endregion

        #region CleanupChapters

        [Fact]
        public void CleanupChapters_AllFilesShouldBeDeleted()
        {
            var filesystem = CreateFileSystem();
            filesystem.AddDirectory($"{CacheDirectory}1/");
            filesystem.AddFile($"{CacheDirectory}1/001.jpg", new MockFileData(""));
            filesystem.AddFile($"{CacheDirectory}1/002.jpg", new MockFileData(""));
            filesystem.AddFile($"{CacheDirectory}3/003.jpg", new MockFileData(""));
            var ds = new DirectoryService(Substitute.For<ILogger<DirectoryService>>(), filesystem);
            var cleanupService = new CacheService(_logger, _unitOfWork, ds,
                new ReadingItemService(Substitute.For<IArchiveService>(),
                    Substitute.For<IBookService>(), Substitute.For<IImageService>(), ds), Substitute.For<IBookmarkService>());

            cleanupService.CleanupChapters(new []{1, 3});
            Assert.Empty(ds.GetFiles(CacheDirectory, searchOption:SearchOption.AllDirectories));
        }


        #endregion

        #region GetCachedEpubFile

        [Fact]
        public void GetCachedEpubFile_ShouldReturnFirstEpub()
        {
            var filesystem = CreateFileSystem();
            filesystem.AddDirectory($"{CacheDirectory}1/");
            filesystem.AddFile($"{DataDirectory}1.epub", new MockFileData(""));
            filesystem.AddFile($"{DataDirectory}2.epub", new MockFileData(""));
            var ds = new DirectoryService(Substitute.For<ILogger<DirectoryService>>(), filesystem);
            var cs = new CacheService(_logger, _unitOfWork, ds,
                new ReadingItemService(Substitute.For<IArchiveService>(),
                    Substitute.For<IBookService>(), Substitute.For<IImageService>(), ds), Substitute.For<IBookmarkService>());

            var c = new Chapter()
            {
                Files = new List<MangaFile>()
                {
                    new MangaFile()
                    {
                        FilePath = $"{DataDirectory}1.epub"
                    },
                    new MangaFile()
                    {
                        FilePath = $"{DataDirectory}2.epub"
                    }
                }
            };
            cs.GetCachedFile(c);
            Assert.Same($"{DataDirectory}1.epub", cs.GetCachedFile(c));
        }

        #endregion

        #region GetCachedPagePath

        [Fact]
        public void GetCachedPagePath_ReturnNullIfNoFiles()
        {
            var filesystem = CreateFileSystem();
            filesystem.AddDirectory($"{CacheDirectory}1/");
            filesystem.AddFile($"{DataDirectory}1.zip", new MockFileData(""));
            filesystem.AddFile($"{DataDirectory}2.zip", new MockFileData(""));

            var c = new Chapter()
            {
                Id = 1,
                Files = new List<MangaFile>()
            };

            var fileIndex = 0;
            foreach (var file in c.Files)
            {
                for (var i = 0; i < file.Pages - 1; i++)
                {
                    filesystem.AddFile($"{CacheDirectory}1/{fileIndex}/{i+1}.jpg", new MockFileData(""));
                }

                fileIndex++;
            }

            var ds = new DirectoryService(Substitute.For<ILogger<DirectoryService>>(), filesystem);
            var cs = new CacheService(_logger, _unitOfWork, ds,
                new ReadingItemService(Substitute.For<IArchiveService>(),
                    Substitute.For<IBookService>(), Substitute.For<IImageService>(), ds), Substitute.For<IBookmarkService>());

            // Flatten to prepare for how GetFullPath expects
            ds.Flatten($"{CacheDirectory}1/");

            var path = cs.GetCachedPagePath(c, 11);
            Assert.Equal(string.Empty, path);
        }

        [Fact]
        public void GetCachedPagePath_GetFileFromFirstFile()
        {
            var filesystem = CreateFileSystem();
            filesystem.AddDirectory($"{CacheDirectory}1/");
            filesystem.AddFile($"{DataDirectory}1.zip", new MockFileData(""));
            filesystem.AddFile($"{DataDirectory}2.zip", new MockFileData(""));

            var c = new Chapter()
            {
                Id = 1,
                Files = new List<MangaFile>()
                {
                    new MangaFile()
                    {
                        Id = 1,
                        FilePath = $"{DataDirectory}1.zip",
                        Pages = 10

                    },
                    new MangaFile()
                    {
                        Id = 2,
                        FilePath = $"{DataDirectory}2.zip",
                        Pages = 5
                    }
                }
            };

            var fileIndex = 0;
            foreach (var file in c.Files)
            {
                for (var i = 0; i < file.Pages; i++)
                {
                    filesystem.AddFile($"{CacheDirectory}1/00{fileIndex}_00{i+1}.jpg", new MockFileData(""));
                }

                fileIndex++;
            }

            var ds = new DirectoryService(Substitute.For<ILogger<DirectoryService>>(), filesystem);
            var cs = new CacheService(_logger, _unitOfWork, ds,
                new ReadingItemService(Substitute.For<IArchiveService>(),
                    Substitute.For<IBookService>(), Substitute.For<IImageService>(), ds), Substitute.For<IBookmarkService>());

            // Flatten to prepare for how GetFullPath expects
            ds.Flatten($"{CacheDirectory}1/");

            Assert.Equal(ds.FileSystem.Path.GetFullPath($"{CacheDirectory}/1/000_001.jpg"), ds.FileSystem.Path.GetFullPath(cs.GetCachedPagePath(c, 0)));

        }


        [Fact]
        public void GetCachedPagePath_GetLastPageFromSingleFile()
        {
            var filesystem = CreateFileSystem();
            filesystem.AddDirectory($"{CacheDirectory}1/");
            filesystem.AddFile($"{DataDirectory}1.zip", new MockFileData(""));

            var c = new Chapter()
            {
                Id = 1,
                Files = new List<MangaFile>()
                {
                    new MangaFile()
                    {
                        Id = 1,
                        FilePath = $"{DataDirectory}1.zip",
                        Pages = 10

                    }
                }
            };
            c.Pages = c.Files.Sum(f => f.Pages);

            var fileIndex = 0;
            foreach (var file in c.Files)
            {
                for (var i = 0; i < file.Pages; i++)
                {
                    filesystem.AddFile($"{CacheDirectory}1/{fileIndex}/{i+1}.jpg", new MockFileData(""));
                }

                fileIndex++;
            }

            var ds = new DirectoryService(Substitute.For<ILogger<DirectoryService>>(), filesystem);
            var cs = new CacheService(_logger, _unitOfWork, ds,
                new ReadingItemService(Substitute.For<IArchiveService>(),
                    Substitute.For<IBookService>(), Substitute.For<IImageService>(), ds), Substitute.For<IBookmarkService>());

            // Flatten to prepare for how GetFullPath expects
            ds.Flatten($"{CacheDirectory}1/");

            // Remember that we start at 0, so this is the 10th file
            var path = cs.GetCachedPagePath(c, c.Pages);
            Assert.Equal(ds.FileSystem.Path.GetFullPath($"{CacheDirectory}/1/000_0{c.Pages}.jpg"), ds.FileSystem.Path.GetFullPath(path));
        }

        [Fact]
        public void GetCachedPagePath_GetFileFromSecondFile()
        {
            var filesystem = CreateFileSystem();
            filesystem.AddDirectory($"{CacheDirectory}1/");
            filesystem.AddFile($"{DataDirectory}1.zip", new MockFileData(""));
            filesystem.AddFile($"{DataDirectory}2.zip", new MockFileData(""));

            var c = new Chapter()
            {
                Id = 1,
                Files = new List<MangaFile>()
                {
                    new MangaFile()
                    {
                        Id = 1,
                        FilePath = $"{DataDirectory}1.zip",
                        Pages = 10

                    },
                    new MangaFile()
                    {
                        Id = 2,
                        FilePath = $"{DataDirectory}2.zip",
                        Pages = 5
                    }
                }
            };

            var fileIndex = 0;
            foreach (var file in c.Files)
            {
                for (var i = 0; i < file.Pages; i++)
                {
                    filesystem.AddFile($"{CacheDirectory}1/{fileIndex}/{i+1}.jpg", new MockFileData(""));
                }

                fileIndex++;
            }

            var ds = new DirectoryService(Substitute.For<ILogger<DirectoryService>>(), filesystem);
            var cs = new CacheService(_logger, _unitOfWork, ds,
                new ReadingItemService(Substitute.For<IArchiveService>(),
                    Substitute.For<IBookService>(), Substitute.For<IImageService>(), ds), Substitute.For<IBookmarkService>());

            // Flatten to prepare for how GetFullPath expects
            ds.Flatten($"{CacheDirectory}1/");

            // Remember that we start at 0, so this is the page + 1 file
            var path = cs.GetCachedPagePath(c, 10);
            Assert.Equal(ds.FileSystem.Path.GetFullPath($"{CacheDirectory}/1/001_001.jpg"), ds.FileSystem.Path.GetFullPath(path));
        }

        #endregion

        #region ExtractChapterFiles

        // [Fact]
        // public void ExtractChapterFiles_ShouldExtractOnlyImages()
        // {
        // const string testDirectory = "/manga/";
        // var fileSystem = new MockFileSystem();
        // for (var i = 0; i < 10; i++)
        // {
        //     fileSystem.AddFile($"{testDirectory}file_{i}.zip", new MockFileData(""));
        // }
        //
        // fileSystem.AddDirectory(CacheDirectory);
        //
        // var ds = new DirectoryService(Substitute.For<ILogger<DirectoryService>>(), fileSystem);
        // var cs = new CacheService(_logger, _unitOfWork, ds,
        //     new MockReadingItemServiceForCacheService(ds));
        //
        //
        //     cs.ExtractChapterFiles(CacheDirectory, new List<MangaFile>()
        //     {
        //         new MangaFile()
        //         {
        //             ChapterId = 1,
        //             Format = MangaFormat.Archive,
        //             Pages = 2,
        //             FilePath =
        //         }
        //     })
        // }

        #endregion
    }
}