diff --git a/classes/class_image_tools.php b/classes/class_image_tools.php
index 1e828854..e4240a94 100644
--- a/classes/class_image_tools.php
+++ b/classes/class_image_tools.php
@@ -1,73 +1,83 @@
 <?
 /**
- * This class determines the thumbnail equivalent of an image's url after being passed the original 
+ * This class determines the thumbnail equivalent of an image's url after being passed the original
  *
-**/
+ **/
 
+/**
+ * The main function, called to get the thumbnail url.
+ */
 function to_thumbnail($url) {
-        $thumb = $url;
-        $extension = pathinfo($url, PATHINFO_EXTENSION);
-		if(contains('whatimg', $url)) {
-			if(hasWhatImgThumb($url)) { 
-				if($extension == 'jpeg') {
-					$thumb = replace_extension($url, '_thumb.jpeg');
-				}
-				if($extension == 'jpg') {
-                                        $thumb = replace_extension($url, '_thumb.jpg');
-                                }
-				if($extension == 'png') {
-					$thumb = replace_extension($url, '_thumb.png');
-				}
-				if($extension == 'gif') {
-					$thumb = replace_extension($url, '_thumb.gif');
-				}
-			}
-		}
-		elseif(contains('imgur', $url)) {
-			$url = cleanImgurUrl($url);
-			if($extension == 'jpeg') {
-				$thumb = replace_extension($url, 'm.jpeg');
-			}
-			if($extension == 'jpg') {
-				$thumb = replace_extension($url, 'm.jpg');
-			}
-			if($extension == 'png') {
-				$thumb = replace_extension($url, 'm.png');
-			}
-			if($extension == 'gif') {
-				$thumb = replace_extension($url, 'm.gif');
-			}
-		}
-        return $thumb;
+    $thumb = $url;
+    $extension = pathinfo($url, PATHINFO_EXTENSION);
+    if (contains('whatimg', $url)) {
+        if (hasWhatImgThumb($url)) {
+            if ($extension == 'jpeg') {
+                $thumb = replace_extension($url, '_thumb.jpeg');
+            }
+            if ($extension == 'jpg') {
+                $thumb = replace_extension($url, '_thumb.jpg');
+            }
+            if ($extension == 'png') {
+                $thumb = replace_extension($url, '_thumb.png');
+            }
+            if ($extension == 'gif') {
+                $thumb = replace_extension($url, '_thumb.gif');
+            }
+        }
+    } elseif (contains('imgur', $url)) {
+        $url = cleanImgurUrl($url);
+        if ($extension == 'jpeg') {
+            $thumb = replace_extension($url, 'm.jpeg');
+        }
+        if ($extension == 'jpg') {
+            $thumb = replace_extension($url, 'm.jpg');
+        }
+        if ($extension == 'png') {
+            $thumb = replace_extension($url, 'm.png');
+        }
+        if ($extension == 'gif') {
+            $thumb = replace_extension($url, 'm.gif');
+        }
+    }
+    return $thumb;
 }
 
-
+/**
+ * Replaces the extension.
+ */
 function replace_extension($string, $extension) {
-        $string =  preg_replace('/\.[^.]*$/', '', $string);
-        $string = $string . $extension;
-        return $string;
+    $string = preg_replace('/\.[^.]*$/', '', $string);
+    $string = $string . $extension;
+    return $string;
 }
 
 function contains($substring, $string) {
-       return $pos = strpos($string, $substring);       
+    return $pos = strpos($string, $substring);
+
 }
 
-function hasWhatImgThumb($url) { 
-	return !contains("_thumb", $url);
+/**
+ * Checks if url points to a whatimg thumbnail.
+ */
+function hasWhatImgThumb($url) {
+    return !contains("_thumb", $url);
 }
 
+/**
+ * Cleans up imgur url if it already has a modifier attached to the end of it.
+ */
 function cleanImgurUrl($url) {
-	$extension = pathinfo($url, PATHINFO_EXTENSION);
-	$path = preg_replace('/\.[^.]*$/', '', $url);
-	if(strlen($path) == 6) {
-		$last = $path[strlen($path)-1];
-		if($last == 'm' || $last == 'l' || $last == 's' || $last == 'h' || $last == 'b') {
-			$path = substr($path, 0, -1);
-		} 
-	}
-	elseif(strlen($path) == 5) {
-		$path .= 'm';		
-	}
-	return $path . "." . $extension;  
+    $extension = pathinfo($url, PATHINFO_EXTENSION);
+    $full = preg_replace('/\.[^.]*$/', '', $url);
+    $base = substr($full, 0, strrpos($full, '/'));
+    $path = substr($full, strrpos($full, '/') + 1);
+    if (strlen($path) == 6) {
+        $last = $path[strlen($path) - 1];
+        if ($last == 'm' || $last == 'l' || $last == 's' || $last == 'h' || $last == 'b') {
+            $path = substr($path, 0, -1);
+        }
+    }
+    return $base . "/" . $path . "." . $extension;
 }
 ?>