Sort Gallery photos by Likes and Comments

pkg/controller/photo/site_gallery.go

@@ -18,6 +18,10 @@ func SiteGallery() http.HandlerFunc {
 	var sortWhitelist = []string{
 		"created_at desc",
 		"created_at asc",
+
+		// Custom (advanced) sort options.
+		"by_likes",
+		"by_comments",
 	}
 
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {

pkg/controller/photo/user_gallery.go

@@ -19,6 +19,10 @@ func UserPhotos() http.HandlerFunc {
 		"pinned desc nulls last, updated_at desc",
 		"created_at desc",
 		"created_at asc",
+
+		// Custom (advanced) sort options.
+		"by_likes",
+		"by_comments",
 	}
 
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {

pkg/models/photo.go

@@ -135,6 +135,24 @@ func PaginateUserPhotos(userID uint64, conf UserGallery, pager *Pagination) ([]*
 		placeholders = append(placeholders, explicit[0])
 	}
 
+	// Custom SORT parameters.
+	switch pager.Sort {
+	case "by_likes":
+		pager.Sort = `(
+			SELECT count(likes.id)
+			FROM likes
+			WHERE likes.table_name = 'photos'
+			AND likes.table_id = photos.id
+		) DESC`
+	case "by_comments":
+		pager.Sort = `(
+			SELECT count(comments.id)
+			FROM comments
+			WHERE comments.table_name = 'photos'
+			AND comments.table_id = photos.id
+		) DESC NULLS LAST`
+	}
+
 	query := DB.Where(
 		strings.Join(wheres, " AND "),
 		placeholders...,
@@ -672,6 +690,24 @@ func PaginateGalleryPhotos(user *User, conf Gallery, pager *Pagination) ([]*Phot
 		)
 	}
 
+	// Custom SORT parameters.
+	switch pager.Sort {
+	case "by_likes":
+		pager.Sort = `(
+			SELECT count(likes.id)
+			FROM likes
+			WHERE likes.table_name = 'photos'
+			AND likes.table_id = photos.id
+		) DESC`
+	case "by_comments":
+		pager.Sort = `(
+			SELECT count(comments.id)
+			FROM comments
+			WHERE comments.table_name = 'photos'
+			AND comments.table_id = photos.id
+		) DESC NULLS LAST`
+	}
+
 	query = query.Order(pager.Sort)
 
 	query.Model(&Photo{}).Count(&pager.Total)

web/templates/photo/gallery.html

@@ -414,6 +414,8 @@
                                             {{end}}
                                             <option value="created_at desc"{{if eq .Sort "created_at desc"}} selected{{end}}>Most recent</option>
                                             <option value="created_at asc"{{if eq .Sort "created_at asc"}} selected{{end}}>Oldest first</option>
+                                            <option value="by_likes"{{if eq .Sort "by_likes"}} selected{{end}}>Most likes</option>
+                                            <option value="by_comments"{{if eq .Sort "by_comments"}} selected{{end}}>Most comments</option>
                                         </select>
                                     </div>
                                 </div>