Kavita/API/Controllers/ReaderController.cs

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Threading.Tasks;
using API.Comparators;
using API.Data.Repositories;
using API.DTOs;
using API.DTOs.Reader;
using API.Entities;
using API.Extensions;
using API.Interfaces;
using API.Interfaces.Services;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Logging;

namespace API.Controllers
{
    /// <summary>
    /// For all things regarding reading, mainly focusing on non-Book related entities
    /// </summary>
    public class ReaderController : BaseApiController
    {
        private readonly IDirectoryService _directoryService;
        private readonly ICacheService _cacheService;
        private readonly IUnitOfWork _unitOfWork;
        private readonly ILogger<ReaderController> _logger;
        private readonly IReaderService _readerService;

        /// <inheritdoc />
        public ReaderController(IDirectoryService directoryService, ICacheService cacheService,
            IUnitOfWork unitOfWork, ILogger<ReaderController> logger, IReaderService readerService)
        {
            _directoryService = directoryService;
            _cacheService = cacheService;
            _unitOfWork = unitOfWork;
            _logger = logger;
            _readerService = readerService;
        }

        /// <summary>
        /// Returns an image for a given chapter. Side effect: This will cache the chapter images for reading.
        /// </summary>
        /// <param name="chapterId"></param>
        /// <param name="page"></param>
        /// <returns></returns>
        [HttpGet("image")]
        public async Task<ActionResult> GetImage(int chapterId, int page)
        {
            if (page < 0) page = 0;
            var chapter = await _cacheService.Ensure(chapterId);
            if (chapter == null) return BadRequest("There was an issue finding image file for reading");

            try
            {
                var (path, _) = await _cacheService.GetCachedPagePath(chapter, page);
                if (string.IsNullOrEmpty(path) || !System.IO.File.Exists(path)) return BadRequest($"No such image for page {page}");

                var content = await _directoryService.ReadFileAsync(path);
                var format = Path.GetExtension(path).Replace(".", "");

                // Calculates SHA1 Hash for byte[]
                Response.AddCacheHeader(content);

                return File(content, "image/" + format);
            }
            catch (Exception)
            {
                _cacheService.CleanupChapters(new []{ chapterId });
                throw;
            }
        }

        /// <summary>
        /// Returns various information about a Chapter. Side effect: This will cache the chapter images for reading.
        /// </summary>
        /// <param name="chapterId"></param>
        /// <returns></returns>
        [HttpGet("chapter-info")]
        public async Task<ActionResult<ChapterInfoDto>> GetChapterInfo(int chapterId)
        {
            var chapter = await _cacheService.Ensure(chapterId);
            if (chapter == null) return BadRequest("Could not find Chapter");

            var dto = await _unitOfWork.ChapterRepository.GetChapterInfoDtoAsync(chapterId);
            var mangaFile = (await _unitOfWork.ChapterRepository.GetFilesForChapterAsync(chapterId)).First();

            return Ok(new ChapterInfoDto()
            {
                ChapterNumber =  dto.ChapterNumber,
                VolumeNumber = dto.VolumeNumber,
                VolumeId = dto.VolumeId,
                FileName = Path.GetFileName(mangaFile.FilePath),
                SeriesName = dto.SeriesName,
                SeriesFormat = dto.SeriesFormat,
                SeriesId = dto.SeriesId,
                LibraryId = dto.LibraryId,
                IsSpecial = dto.IsSpecial,
                Pages = dto.Pages,
            });
        }


        [HttpPost("mark-read")]
        public async Task<ActionResult> MarkRead(MarkReadDto markReadDto)
        {
            var user = await _unitOfWork.UserRepository.GetUserByUsernameAsync(User.GetUsername(), AppUserIncludes.Progress);
            var volumes = await _unitOfWork.SeriesRepository.GetVolumes(markReadDto.SeriesId);
            user.Progresses ??= new List<AppUserProgress>();
            foreach (var volume in volumes)
            {
                foreach (var chapter in volume.Chapters)
                {
                    var userProgress = GetUserProgressForChapter(user, chapter);

                    if (userProgress == null)
                    {
                        user.Progresses.Add(new AppUserProgress
                        {
                            PagesRead = chapter.Pages,
                            VolumeId = volume.Id,
                            SeriesId = markReadDto.SeriesId,
                            ChapterId = chapter.Id
                        });
                    }
                    else
                    {
                        userProgress.PagesRead = chapter.Pages;
                        userProgress.SeriesId = markReadDto.SeriesId;
                        userProgress.VolumeId = volume.Id;
                    }
                }
            }

            _unitOfWork.UserRepository.Update(user);

            if (await _unitOfWork.CommitAsync())
            {
                return Ok();
            }


            return BadRequest("There was an issue saving progress");
        }

        private static AppUserProgress GetUserProgressForChapter(AppUser user, Chapter chapter)
        {
            AppUserProgress userProgress = null;
            try
            {
                userProgress =
                    user.Progresses.SingleOrDefault(x => x.ChapterId == chapter.Id && x.AppUserId == user.Id);
            }
            catch (Exception)
            {
                // There is a very rare chance that user progress will duplicate current row. If that happens delete one with less pages
                var progresses = user.Progresses.Where(x => x.ChapterId == chapter.Id && x.AppUserId == user.Id).ToList();
                if (progresses.Count > 1)
                {
                    user.Progresses = new List<AppUserProgress>()
                    {
                        user.Progresses.First()
                    };
                    userProgress = user.Progresses.First();
                }
            }

            return userProgress;
        }

        /// <summary>
        /// Marks a Series as Unread (progress)
        /// </summary>
        /// <param name="markReadDto"></param>
        /// <returns></returns>
        [HttpPost("mark-unread")]
        public async Task<ActionResult> MarkUnread(MarkReadDto markReadDto)
        {
            var user = await _unitOfWork.UserRepository.GetUserByUsernameAsync(User.GetUsername(), AppUserIncludes.Progress);
            var volumes = await _unitOfWork.SeriesRepository.GetVolumes(markReadDto.SeriesId);
            user.Progresses ??= new List<AppUserProgress>();
            foreach (var volume in volumes)
            {
                foreach (var chapter in volume.Chapters)
                {
                    var userProgress = GetUserProgressForChapter(user, chapter);

                    if (userProgress == null) continue;
                    userProgress.PagesRead = 0;
                    userProgress.SeriesId = markReadDto.SeriesId;
                    userProgress.VolumeId = volume.Id;
                }
            }

            _unitOfWork.UserRepository.Update(user);

            if (await _unitOfWork.CommitAsync())
            {
                return Ok();
            }


            return BadRequest("There was an issue saving progress");
        }

        /// <summary>
        /// Marks all chapters within a volume as unread
        /// </summary>
        /// <param name="markVolumeReadDto"></param>
        /// <returns></returns>
        [HttpPost("mark-volume-unread")]
        public async Task<ActionResult> MarkVolumeAsUnread(MarkVolumeReadDto markVolumeReadDto)
        {
            var user = await _unitOfWork.UserRepository.GetUserByUsernameAsync(User.GetUsername(), AppUserIncludes.Progress);

            var chapters = await _unitOfWork.ChapterRepository.GetChaptersAsync(markVolumeReadDto.VolumeId);
            foreach (var chapter in chapters)
            {
                user.Progresses ??= new List<AppUserProgress>();
                var userProgress = user.Progresses.FirstOrDefault(x => x.ChapterId == chapter.Id && x.AppUserId == user.Id);

                if (userProgress == null)
                {
                    user.Progresses.Add(new AppUserProgress
                    {
                        PagesRead = 0,
                        VolumeId = markVolumeReadDto.VolumeId,
                        SeriesId = markVolumeReadDto.SeriesId,
                        ChapterId = chapter.Id
                    });
                }
                else
                {
                    userProgress.PagesRead = 0;
                    userProgress.SeriesId = markVolumeReadDto.SeriesId;
                    userProgress.VolumeId = markVolumeReadDto.VolumeId;
                }
            }

            _unitOfWork.UserRepository.Update(user);

            if (await _unitOfWork.CommitAsync())
            {
                return Ok();
            }

            return BadRequest("Could not save progress");
        }

        /// <summary>
        /// Marks all chapters within a volume as Read
        /// </summary>
        /// <param name="markVolumeReadDto"></param>
        /// <returns></returns>
        [HttpPost("mark-volume-read")]
        public async Task<ActionResult> MarkVolumeAsRead(MarkVolumeReadDto markVolumeReadDto)
        {
            var user = await _unitOfWork.UserRepository.GetUserByUsernameAsync(User.GetUsername(), AppUserIncludes.Progress);

            var chapters = await _unitOfWork.ChapterRepository.GetChaptersAsync(markVolumeReadDto.VolumeId);
            foreach (var chapter in chapters)
            {
                user.Progresses ??= new List<AppUserProgress>();
                var userProgress = user.Progresses.FirstOrDefault(x => x.ChapterId == chapter.Id && x.AppUserId == user.Id);

                if (userProgress == null)
                {
                    user.Progresses.Add(new AppUserProgress
                    {
                        PagesRead = chapter.Pages,
                        VolumeId = markVolumeReadDto.VolumeId,
                        SeriesId = markVolumeReadDto.SeriesId,
                        ChapterId = chapter.Id
                    });
                }
                else
                {
                    userProgress.PagesRead = chapter.Pages;
                    userProgress.SeriesId = markVolumeReadDto.SeriesId;
                    userProgress.VolumeId = markVolumeReadDto.VolumeId;
                }
            }

            _unitOfWork.UserRepository.Update(user);

            if (await _unitOfWork.CommitAsync())
            {
                return Ok();
            }

            return BadRequest("Could not save progress");
        }

        /// <summary>
        /// Returns Progress (page number) for a chapter for the logged in user
        /// </summary>
        /// <param name="chapterId"></param>
        /// <returns></returns>
        [HttpGet("get-progress")]
        public async Task<ActionResult<ProgressDto>> GetProgress(int chapterId)
        {
            var user = await _unitOfWork.UserRepository.GetUserByUsernameAsync(User.GetUsername(), AppUserIncludes.Progress);
            var progressBookmark = new ProgressDto()
            {
                PageNum = 0,
                ChapterId = chapterId,
                VolumeId = 0,
                SeriesId = 0
            };
            if (user.Progresses == null) return Ok(progressBookmark);
            var progress = user.Progresses.SingleOrDefault(x => x.AppUserId == user.Id && x.ChapterId == chapterId);

            if (progress != null)
            {
                progressBookmark.SeriesId = progress.SeriesId;
                progressBookmark.VolumeId = progress.VolumeId;
                progressBookmark.PageNum = progress.PagesRead;
                progressBookmark.BookScrollId = progress.BookScrollId;
            }
            return Ok(progressBookmark);
        }

        /// <summary>
        /// Save page against Chapter for logged in user
        /// </summary>
        /// <param name="progressDto"></param>
        /// <returns></returns>
        [HttpPost("progress")]
        public async Task<ActionResult> BookmarkProgress(ProgressDto progressDto)
        {
            var user = await _unitOfWork.UserRepository.GetUserByUsernameAsync(User.GetUsername());

            if (await _readerService.SaveReadingProgress(progressDto, user.Id)) return Ok(true);

            return BadRequest("Could not save progress");
        }

        /// <summary>
        /// Returns a list of bookmarked pages for a given Chapter
        /// </summary>
        /// <param name="chapterId"></param>
        /// <returns></returns>
        [HttpGet("get-bookmarks")]
        public async Task<ActionResult<IEnumerable<BookmarkDto>>> GetBookmarks(int chapterId)
        {
            var user = await _unitOfWork.UserRepository.GetUserByUsernameAsync(User.GetUsername(), AppUserIncludes.Bookmarks);
            if (user.Bookmarks == null) return Ok(Array.Empty<BookmarkDto>());
            return Ok(await _unitOfWork.UserRepository.GetBookmarkDtosForChapter(user.Id, chapterId));
        }

        /// <summary>
        /// Returns a list of all bookmarked pages for a User
        /// </summary>
        /// <returns></returns>
        [HttpGet("get-all-bookmarks")]
        public async Task<ActionResult<IEnumerable<BookmarkDto>>> GetAllBookmarks()
        {
            var user = await _unitOfWork.UserRepository.GetUserByUsernameAsync(User.GetUsername(), AppUserIncludes.Bookmarks);
            if (user.Bookmarks == null) return Ok(Array.Empty<BookmarkDto>());
            return Ok(await _unitOfWork.UserRepository.GetAllBookmarkDtos(user.Id));
        }

        /// <summary>
        /// Removes all bookmarks for all chapters linked to a Series
        /// </summary>
        /// <param name="dto"></param>
        /// <returns></returns>
        [HttpPost("remove-bookmarks")]
        public async Task<ActionResult> RemoveBookmarks(RemoveBookmarkForSeriesDto dto)
        {
            var user = await _unitOfWork.UserRepository.GetUserByUsernameAsync(User.GetUsername(), AppUserIncludes.Bookmarks);
            if (user.Bookmarks == null) return Ok("Nothing to remove");
            try
            {
                user.Bookmarks = user.Bookmarks.Where(bmk => bmk.SeriesId != dto.SeriesId).ToList();
                _unitOfWork.UserRepository.Update(user);

                if (await _unitOfWork.CommitAsync())
                {
                    return Ok();
                }
            }
            catch (Exception ex)
            {
                _logger.LogError(ex, "There was an exception when trying to clear bookmarks");
                await _unitOfWork.RollbackAsync();
            }

            return BadRequest("Could not clear bookmarks");

        }

        /// <summary>
        /// Returns all bookmarked pages for a given volume
        /// </summary>
        /// <param name="volumeId"></param>
        /// <returns></returns>
        [HttpGet("get-volume-bookmarks")]
        public async Task<ActionResult<IEnumerable<BookmarkDto>>> GetBookmarksForVolume(int volumeId)
        {
            var user = await _unitOfWork.UserRepository.GetUserByUsernameAsync(User.GetUsername(), AppUserIncludes.Bookmarks);
            if (user.Bookmarks == null) return Ok(Array.Empty<BookmarkDto>());
            return Ok(await _unitOfWork.UserRepository.GetBookmarkDtosForVolume(user.Id, volumeId));
        }

        /// <summary>
        /// Returns all bookmarked pages for a given series
        /// </summary>
        /// <param name="seriesId"></param>
        /// <returns></returns>
        [HttpGet("get-series-bookmarks")]
        public async Task<ActionResult<IEnumerable<BookmarkDto>>> GetBookmarksForSeries(int seriesId)
        {
            var user = await _unitOfWork.UserRepository.GetUserByUsernameAsync(User.GetUsername(), AppUserIncludes.Bookmarks);
            if (user.Bookmarks == null) return Ok(Array.Empty<BookmarkDto>());

            return Ok(await _unitOfWork.UserRepository.GetBookmarkDtosForSeries(user.Id, seriesId));
        }

        /// <summary>
        /// Bookmarks a page against a Chapter
        /// </summary>
        /// <param name="bookmarkDto"></param>
        /// <returns></returns>
        [HttpPost("bookmark")]
        public async Task<ActionResult> BookmarkPage(BookmarkDto bookmarkDto)
        {
            // Don't let user save past total pages.
            bookmarkDto.Page = await _readerService.CapPageToChapter(bookmarkDto.ChapterId, bookmarkDto.Page);

            try
            {
                var user = await _unitOfWork.UserRepository.GetUserByUsernameAsync(User.GetUsername(), AppUserIncludes.Bookmarks);
                var userBookmark =
                    await _unitOfWork.UserRepository.GetBookmarkForPage(bookmarkDto.Page, bookmarkDto.ChapterId, user.Id);

               if (userBookmark == null)
               {
                   user.Bookmarks ??= new List<AppUserBookmark>();
                   user.Bookmarks.Add(new AppUserBookmark()
                   {
                       Page = bookmarkDto.Page,
                       VolumeId = bookmarkDto.VolumeId,
                       SeriesId = bookmarkDto.SeriesId,
                       ChapterId = bookmarkDto.ChapterId,
                   });
                   _unitOfWork.UserRepository.Update(user);
               }


               if (await _unitOfWork.CommitAsync())
               {
                  return Ok();
               }
            }
            catch (Exception)
            {
               await _unitOfWork.RollbackAsync();
            }

            return BadRequest("Could not save bookmark");
        }

        /// <summary>
        /// Removes a bookmarked page for a Chapter
        /// </summary>
        /// <param name="bookmarkDto"></param>
        /// <returns></returns>
        [HttpPost("unbookmark")]
        public async Task<ActionResult> UnBookmarkPage(BookmarkDto bookmarkDto)
        {
            var user = await _unitOfWork.UserRepository.GetUserByUsernameAsync(User.GetUsername(), AppUserIncludes.Bookmarks);

            if (user.Bookmarks == null) return Ok();
            try {
                user.Bookmarks = user.Bookmarks.Where(x =>
                    x.ChapterId == bookmarkDto.ChapterId
                    && x.AppUserId == user.Id
                    && x.Page != bookmarkDto.Page).ToList();

                _unitOfWork.UserRepository.Update(user);

                if (await _unitOfWork.CommitAsync())
                {
                    return Ok();
                }
            }
            catch (Exception)
            {
                await _unitOfWork.RollbackAsync();
            }

            return BadRequest("Could not remove bookmark");
        }

        /// <summary>
        /// Returns the next logical chapter from the series.
        /// </summary>
        /// <example>
        /// V1 → V2 → V3 chapter 0 → V3 chapter 10 → SP 01 → SP 02
        /// </example>
        /// <param name="seriesId"></param>
        /// <param name="volumeId"></param>
        /// <param name="currentChapterId"></param>
        /// <returns>chapter id for next manga</returns>
        [HttpGet("next-chapter")]
        public async Task<ActionResult<int>> GetNextChapter(int seriesId, int volumeId, int currentChapterId)
        {
            var userId = await _unitOfWork.UserRepository.GetUserIdByUsernameAsync(User.GetUsername());
            return await _readerService.GetNextChapterIdAsync(seriesId, volumeId, currentChapterId, userId);
        }


        /// <summary>
        /// Returns the previous logical chapter from the series.
        /// </summary>
        /// <example>
        /// V1 ← V2 ← V3 chapter 0 ← V3 chapter 10 ← SP 01 ← SP 02
        /// </example>
        /// <param name="seriesId"></param>
        /// <param name="volumeId"></param>
        /// <param name="currentChapterId"></param>
        /// <returns>chapter id for next manga</returns>
        [HttpGet("prev-chapter")]
        public async Task<ActionResult<int>> GetPreviousChapter(int seriesId, int volumeId, int currentChapterId)
        {
            var userId = await _unitOfWork.UserRepository.GetUserIdByUsernameAsync(User.GetUsername());
            return await _readerService.GetPrevChapterIdAsync(seriesId, volumeId, currentChapterId, userId);
        }

    }
}