Add explicit width/height controls for embedded images in Remarkup

Summary: User request. See screenshot.

Test Plan: doge

Reviewers: btrahan, bigo

Reviewed By: btrahan

CC: aran

Differential Revision: https://secure.phabricator.com/D7610

src/applications/files/remarkup/PhabricatorRemarkupRuleEmbedFile.php

@@ -50,9 +50,11 @@ final class PhabricatorRemarkupRuleEmbedFile
 
   private function getFileOptions($option_string) {
     $options = array(
-      'size'    => 'thumb',
+      'size'    => null,
       'layout'  => 'left',
       'float'   => false,
+      'width'   => null,
+      'height'  => null,
     );
 
     if ($option_string) {
@@ -73,6 +75,22 @@ final class PhabricatorRemarkupRuleEmbedFile
 
     $attrs = array();
     $image_class = null;
+
+    $use_size = true;
+    if (!$options['size']) {
+      $width = $this->parseDimension($options['width']);
+      $height = $this->parseDimension($options['height']);
+      if ($width || $height) {
+        $use_size = false;
+        $attrs += array(
+          'src' => $file->getBestURI(),
+          'width' => $width,
+          'height' => $height,
+        );
+      }
+    }
+
+    if ($use_size) {
       switch ((string)$options['size']) {
         case 'full':
           $attrs += array(
@@ -91,6 +109,7 @@ final class PhabricatorRemarkupRuleEmbedFile
           $image_class = 'phabricator-remarkup-embed-image';
           break;
       }
+    }
 
     $img = phutil_tag('img', $attrs);
 
@@ -186,4 +205,14 @@ final class PhabricatorRemarkupRuleEmbedFile
       ->setFileViewable($options['viewable']);
   }
 
+  private function parseDimension($string) {
+    $string = trim($string);
+
+    if (preg_match('/^(?:\d*\\.)?\d+%?$/', $string)) {
+      return $string;
+    }
+
+    return null;
+  }
+
 }

src/docs/user/userguide/remarkup.diviner

@@ -345,6 +345,8 @@ Valid options are:
   - **size** thumb (default), full
   - **name** with `layout=link` or for non-images, use this name for the link
     text
+  - **width** Scale image to a specific width.
+  - **height** Scale image to a specific height.
 
 == Embedding Countdowns