Moved thumbnail generation from media controller to media service

1 files changed, 87 insertions, 18 deletions

diff --git a/Services/MediaService.cs b/Services/MediaService.cs
index f26d005..0b506b0 100644
--- a/Services/MediaService.cs
+++ b/Services/MediaService.cs
@@ -3,6 +3,7 @@ using Microsoft.EntityFrameworkCore;
 using MimeDetective;
 using MimeDetective.Definitions;
 using System.Security.Cryptography;
+using System.Text.RegularExpressions;
 
 namespace HyperBooru.Services;
 
@@ -24,6 +25,10 @@ public interface IMediaService {
 
     public void Delete(Guid media);
     public void Delete(Media media);
+    public void DeleteThumbnails(Guid media);
+    public void DeleteThumbnails(Media media);
+    public Stream GetThumbnail(Guid media, int? width, int? height);
+    public Stream GetThumbnail(Media media, int? width, int? height);
     public string GetPath(Media media);
     public string GetPath(Media media, int width, int height);
 
@@ -181,29 +186,22 @@ public class MediaService : IMediaService {
         using var db = dbFactory.CreateDbContext();
         var m = db.Media.First(m => m.Guid == media);
 
-        try {
-            System.IO.File.Delete(
-                Path.Join(
-                    config.MediaBasePath,
-                    m.Guid.ToString().Substring(0, 2),
-                    m.Guid.ToString().Substring(2, 2),
-                    m.Guid.ToString()));
-        } catch(IOException) {}
+        var path = Path.Join(
+            config.MediaBasePath,
+            m.Guid.ToString().Substring(0, 2),
+            m.Guid.ToString().Substring(2, 2),
+            m.Guid.ToString());
 
         try {
-            System.IO.Directory.Delete(
-                Path.Join(
-                    config.MediaBasePath,
-                    m.Guid.ToString().Substring(0, 2),
-                    m.Guid.ToString().Substring(2, 2)));
+            var fileInfo = new FileInfo(path);
+            fileInfo.Delete();
+            fileInfo.Directory?.Delete();
+            fileInfo.Directory?.Parent?.Delete();
         } catch(IOException) {}
 
         try {
-            System.IO.Directory.Delete(
-                Path.Join(
-                    config.MediaBasePath,
-                    m.Guid.ToString().Substring(0, 2)));
-        } catch(IOException) {}
+            DeleteThumbnails(media);
+        } catch {}
 
         db.Media.Remove(m);
         db.SaveChanges();
@@ -212,6 +210,77 @@ public class MediaService : IMediaService {
     public void Delete(Media media) =>
         Delete(media.Guid);
 
+    public void DeleteThumbnails(Guid media) {
+        var dir = new DirectoryInfo(Path.Join(
+            config.ThumbnailBasePath,
+            media.ToString().Substring(0, 2),
+            media.ToString().Substring(2, 2)));
+
+        var pattern = new Regex($"^{media}-[0-9]+-[0-9]+$");
+        var toDelete = dir.GetFiles()
+            .Where(f => pattern.IsMatch(f.Name))
+            .ToList();
+
+        List<Exception> exceptions = new();
+
+        foreach(var file in toDelete) {
+            try {
+                file.Delete();
+            } catch(Exception e) {
+                exceptions.Add(e);
+            }
+        }
+
+        try {
+            dir.Delete();
+            dir.Parent?.Delete();
+        } catch(Exception e) {
+            exceptions.Add(e);
+        }
+
+        // TODO: wrap the AggregateException in a ThumbnailException
+        if(exceptions.Count() > 1)
+            throw new AggregateException(exceptions);
+    }
+
+    public void DeleteThumbnails(Media media) =>
+        DeleteThumbnails(media.Guid);
+
+    public Stream GetThumbnail(Guid media, int? width, int? height) {
+        using var db = dbFactory.CreateDbContext();
+        var m = db.Media.First(m => m.Guid == media);
+        if(m is null)
+            throw new ObjectNotFoundException(media);
+
+        if(m.MimeType.Split("/")[0] != "image")
+            throw new ThumbnailException("Media object not an image", m);
+
+        using var image = new MagickImage(GetPath(m));
+
+        if(width is null && height is null)
+            throw new ThumbnailException("Both width and height cannot be null!", m);
+
+        if(width > image.Width || height > image.Height)
+            throw new ThumbnailException("Requested thumbnail size is larger than original media", m);
+
+        #pragma warning disable CS8629
+        int w = (int) (width  is not null ? width  : image.Width  * height / image.Height);
+        int h = (int) (height is not null ? height : image.Height * width  / image.Width);
+        #pragma warning restore CS8629
+
+        var thumbPath = GetPath(m, w, h);
+
+        if(!System.IO.File.Exists(thumbPath)) {
+            image.Resize(w, h);
+            image.Write(thumbPath);
+        }
+
+        return System.IO.File.OpenRead(thumbPath);
+    }
+
+    public Stream GetThumbnail(Media media, int? width, int? height) =>
+        GetThumbnail(media.Guid, width, height);
+
     public string GetPath(Media media) {
         var fileInfo = new FileInfo(
             Path.Join(