From d92e9e7602b5f989beb9d8f820dd20b4037dc2bb Mon Sep 17 00:00:00 2001
From: Joseph Milazzo <joseph.v.milazzo@gmail.com>
Date: Wed, 5 May 2021 16:48:39 -0500
Subject: [PATCH] Implemented the ability to move between volumes (reading)
 automatically without existing the app. (#198)

---
 API/Controllers/ReaderController.cs | 75 +++++++++++++++++++++++++++++
 API/Controllers/SeriesController.cs | 14 +-----
 2 files changed, 77 insertions(+), 12 deletions(-)

diff --git a/API/Controllers/ReaderController.cs b/API/Controllers/ReaderController.cs
index e3927146b..020e67c0b 100644
--- a/API/Controllers/ReaderController.cs
+++ b/API/Controllers/ReaderController.cs
@@ -239,5 +239,80 @@ namespace API.Controllers
 
             return BadRequest("Could not save progress");
         }
+
+        /// <summary>
+        /// Returns the next logical volume from the series.
+        /// </summary>
+        /// <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 user = await _unitOfWork.UserRepository.GetUserByUsernameAsync(User.GetUsername());
+            var volumes = await _unitOfWork.SeriesRepository.GetVolumesDtoAsync(seriesId, user.Id);
+            var currentVolume = await _unitOfWork.SeriesRepository.GetVolumeAsync(volumeId);
+
+            var next = false;
+            if (currentVolume.Number == 0)
+            {
+                foreach (var chapter in currentVolume.Chapters)
+                {
+                    if (next)
+                    {
+                        return Ok(chapter.Id);
+                    }
+                    if (currentChapterId == chapter.Id) next = true;
+                }
+            }
+
+            foreach (var volume in volumes)
+            {
+                if (volume.Number == currentVolume.Number + 1)
+                {
+                    return Ok(volume.Chapters.FirstOrDefault()?.Id);
+                }
+            }
+            return Ok(-1);
+        }
+        
+        /// <summary>
+        /// Returns the previous logical volume from the series.
+        /// </summary>
+        /// <param name="seriesId"></param>
+        /// <param name="volumeId"></param>
+        /// <returns>chapter id for next manga</returns>
+        [HttpGet("prev-chapter")]
+        public async Task<ActionResult<int>> GetPreviousChapter(int seriesId, int volumeId, int currentChapterId)
+        {
+            var user = await _unitOfWork.UserRepository.GetUserByUsernameAsync(User.GetUsername());
+            var volumes = await _unitOfWork.SeriesRepository.GetVolumesDtoAsync(seriesId, user.Id);
+            var currentVolume = await _unitOfWork.SeriesRepository.GetVolumeAsync(volumeId);
+
+            var next = false;
+            if (currentVolume.Number == 0)
+            {
+                var chapters = currentVolume.Chapters.Reverse();
+                foreach (var chapter in chapters)
+                {
+                    if (next)
+                    {
+                        return Ok(chapter.Id);
+                    }
+                    if (currentChapterId == chapter.Id) next = true;
+                }
+            }
+
+            foreach (var volume in volumes.Reverse())
+            {
+                if (volume.Number == currentVolume.Number - 1)
+                {
+                    return Ok(volume.Chapters.LastOrDefault()?.Id);
+                }
+            }
+            return Ok(-1);
+        }
+        
     }
 }
\ No newline at end of file
diff --git a/API/Controllers/SeriesController.cs b/API/Controllers/SeriesController.cs
index 01737dfef..caa69b15f 100644
--- a/API/Controllers/SeriesController.cs
+++ b/API/Controllers/SeriesController.cs
@@ -1,4 +1,5 @@
 using System.Collections.Generic;
+using System.Linq;
 using System.Threading.Tasks;
 using API.DTOs;
 using API.Entities;
@@ -89,18 +90,7 @@ namespace API.Controllers
             return Ok(await _unitOfWork.VolumeRepository.GetChapterDtoAsync(chapterId));
         }
 
-        /// <summary>
-        /// Returns the next logical volume from the series.
-        /// </summary>
-        /// <param name="seriesId"></param>
-        /// <param name="volumeId"></param>
-        /// <returns>chapter id for next manga</returns>
-        [HttpGet("next-volume")]
-        public async Task<ActionResult<int>> GetNextChapter(int seriesId, int volumeId)
-        {
-            
-            return Ok();
-        }
+        
         
 
         [HttpPost("update-rating")]