Moved thumbnail generation from media controller to media service

6 files changed, 68 insertions, 36 deletions

diff --git a/Controllers/MediaController.cs b/Controllers/MediaController.cs
index 674b406..85dfc65 100644
--- a/Controllers/MediaController.cs
+++ b/Controllers/MediaController.cs
@@ -38,39 +38,17 @@ public class MediaController : Controller {
     [HttpGet("thumb/{mediaId}")]
     public IActionResult Thumbnail(
         [FromRoute] Guid mediaId,
-        [FromQuery] int? w,
-        [FromQuery] int? h) {
+        [FromQuery(Name = "w")] int? width,
+        [FromQuery(Name = "h")] int? height) {
 
-        var media = db.Media.First(m => m.Guid == mediaId);
-        if(media is null)
-            return NotFound();
-
-        if(media.MimeType.Split("/")[0] != "image")
-            return BadRequest("Media object not an image");
-
-        using var image = new MagickImage(mediaService.GetPath(media));
-
-        if(w is null && h is null)
-            return BadRequest("Both width and height cannot be null!");
-
-        if(w > image.Width || h > image.Height)
-            return BadRequest("Requested thumbnail size is larger than original media");
-
-        #pragma warning disable CS8629
-        int width  = (int)(w is not null ? w : image.Width * h / image.Height);
-        int height = (int)(h is not null ? h : image.Height * w / image.Width);
-        #pragma warning restore CS8629
-
-        var thumbPath = mediaService.GetPath(media, width, height);
-
-        if(!System.IO.File.Exists(thumbPath)) {
-            image.Resize(width, height);
-            image.Write(thumbPath);
+        try {
+            var thumb = mediaService.GetThumbnail(mediaId, width, height);
+            return new FileStreamResult(thumb, "image/jpeg");
+        } catch(ThumbnailException e) {
+            return BadRequest(e.Message);
+        } catch(ObjectNotFoundException e) {
+            return NotFound(e.Message);
         }
-
-        var fs = System.IO.File.OpenRead(thumbPath);
-
-        return new FileStreamResult(fs, "image/jpeg");
     }
 
     [HttpDelete("{mediaId}")]
diff --git a/Exception.cs b/Exception.cs
index 528be52..2005b1a 100644
--- a/Exception.cs
+++ b/Exception.cs
@@ -9,6 +9,13 @@ public class HBException : Exception {
         : base(message, inner) {}
 }
 
+public class ObjectNotFoundException : HBException {
+    public Guid Guid { get; set; }
+
+    public ObjectNotFoundException(Guid guid)
+        : base($"Object not found: {guid}") {}
+}
+
 public class MediaException : HBException {
     public Media? Media { get; set; }
 
@@ -20,6 +27,9 @@ public class MediaException : HBException {
 public class MediaCreateException : MediaException {
     public MediaCreateException(string message)
         : base(message) {}
-    public MediaCreateException(string message, Media media)
-        : base(message, media) {}
+}
+
+public class ThumbnailException : MediaException {
+    public ThumbnailException(string message, Media media)
+        :base(message, media) {}
 }
diff --git a/Pages/Gallery.razor b/Pages/Gallery.razor
index e5b1e7b..a582c02 100644
--- a/Pages/Gallery.razor
+++ b/Pages/Gallery.razor
@@ -11,8 +11,11 @@
 <link rel="stylesheet" href="@(nameof(HyperBooru)).styles.css"/>
 
 @foreach(var media in Media) {
+    // Precalculate thumbnail size to help the browser
+    // lay out the images during initial page load
+    int width = media.Width * 200 / media.Height;
     <a href="/ViewMedia?m=@(media.Guid)">
-        <img src="/media/thumb/@(media.Guid)?h=200" />
+        <img src="/media/thumb/@(media.Guid)?h=200" width=@width height="200"/>
     </a>
 }
 
diff --git a/Services/MediaService.cs b/Services/MediaService.cs
index 8c2a5e0..ccee027 100644
--- a/Services/MediaService.cs
+++ b/Services/MediaService.cs
@@ -24,6 +24,8 @@ public interface IMediaService {
 
     public void Delete(Guid media);
     public void Delete(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);
 
@@ -206,6 +208,41 @@ public class MediaService : IMediaService {
     public void Delete(Media media) =>
         Delete(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(
diff --git a/Todo.md b/Todo.md
index ee1aad3..89dc6db 100644
--- a/Todo.md
+++ b/Todo.md
@@ -8,14 +8,14 @@
 # Short-term Features
  - Store original filesize as part of uploaded files
  - Progressive page loading
- - Media metadata (width, height, etc)
  - Proper thumbnail generation
  - Deleting media also deletes thumbnails
  - Video support
  - User/security support
- - About page
 
 #Long-term Features
+ - Search engine includes implicit tags
+ - Periodic thumbnail scrubbing
  - Search tags from ViewMedia page
  - Loading animations
  - Keyboard shortcuts
diff --git a/wwwroot/styles/global.css b/wwwroot/styles/global.css
index 2757d09..de0a0ac 100644
--- a/wwwroot/styles/global.css
+++ b/wwwroot/styles/global.css
@@ -23,6 +23,10 @@
     --col-switch-bg-hl:           var(--col-accent-pri);
 }
 
+::selection {
+    background: var(--col-accent-pri);
+}
+
 body {
     background:     var(--col-bg);
     color:          white;