Add width & height data to thumbnails

gallery/models/album.py

@@ -1,4 +1,5 @@
 from datetime import datetime
+from math import floor
 
 from django.core.exceptions import ValidationError
 from django.db import models
@@ -27,13 +28,37 @@ class Album(models.Model):
         return total_views
 
     @property
-    def cover_url(self):
-        if self.cover:
-            return self.cover.photo_md.url
-        random_cover = self.photos.order_by('-width').first()
-        if random_cover:
-            return random_cover.photo_md.url
-        return static('img/placeholder.png')
+    def cover_image_data(self):
+        def compute_size(photo, max_w=720, max_h=720):
+            if not photo.width or not photo.height:
+                return (None, None)
+            aspect = photo.aspect_ratio
+            if photo.width > photo.height:
+                w = min(photo.width, max_w)
+                h = floor(w / aspect)
+            else:
+                h = min(photo.height, max_h)
+                w = floor(h * aspect)
+            return (w, h)
+
+        photo = self.cover or self.photos.order_by('-width').first()
+        if photo:
+            url = photo.photo_md.url
+            w, h = compute_size(photo)
+            return {
+                "url": url,
+                "width": w,
+                "height": h,
+                "aspect_ratio": round(photo.aspect_ratio, 3)
+            }
+
+        return {
+            "url": static('img/placeholder.png'),
+            "width": 1200,
+            "height": 800,
+            "aspect_ratio": 1.5
+        }
+
 
     def save(self, *args, **kwargs):
         if not self.slug:

gallery/templates/gallery/album_list.html

@@ -29,10 +29,12 @@
                 <!-- Album cover image -->
                 <div class="uk-card-media-top">
                     <a href="{{ album.get_absolute_url }}">
-                        <img src="{{ album.cover_url }}" 
-                            style="aspect-ratio: {{ album.cover.aspect_ratio }};"
+                        <img src="{{ album.cover_image_data.url }}"
+                            width="{{ album.cover_image_data.width }}"
+                            height="{{ album.cover_image_data.height }}"
+                            style="aspect-ratio: {{ album.cover_image_data.aspect_ratio }};"
                             alt="Cover image for {{ album.name }}"
-                            title="{{ album.name }}" 
+                            title="{{ album.name }}"
                             loading="lazy">
                     </a>
                 </div>

gallery/templates/gallery/search.html

@@ -29,10 +29,12 @@
                     <!-- Album cover image -->
                     <div class="uk-card-media-top">
                         <a href="{{ album.get_absolute_url }}">
-                            <img src="{{ album.cover_url }}" 
-                                style="aspect-ratio: {{ album.cover.aspect_ratio }};"
+                            <img src="{{ album.cover_image_data.url }}"
+                                width="{{ album.cover_image_data.width }}"
+                                height="{{ album.cover_image_data.height }}"
+                                style="aspect-ratio: {{ album.cover_image_data.aspect_ratio }};"
                                 alt="Cover image for {{ album.name }}"
-                                title="{{ album.name }}" 
+                                title="{{ album.name }}"
                                 loading="lazy">
                         </a>
                     </div>