Remarkup rule to embed images

Summary:
Ref T4190. Added the remarkup rule to embed images:

Syntax is as follows:

`{image <IMAGE_URL>}`

Parameters are also supported, like:
`{image uri=<IMAGE_URI>, width=500px, height=200px, alt=picture of a moose, href=google.com}`

URLs without a protocol are not supported.

Test Plan: Tested with many of the syntax variations. If the provided URL doesn't point to an image, then a broken image icon will be shown.

Reviewers: epriestley, #blessed_reviewers

Reviewed By: epriestley, #blessed_reviewers

Subscribers: Korvin, epriestley, yelirekim

Maniphest Tasks: T4190

Differential Revision: https://secure.phabricator.com/D16597

src/__phutil_library_map__.php

@@ -2688,6 +2688,7 @@ phutil_register_library_map(array(
     'PhabricatorIconSetEditField' => 'applications/transactions/editfield/PhabricatorIconSetEditField.php',
     'PhabricatorIconSetIcon' => 'applications/files/iconset/PhabricatorIconSetIcon.php',
     'PhabricatorImageMacroRemarkupRule' => 'applications/macro/markup/PhabricatorImageMacroRemarkupRule.php',
+    'PhabricatorImageRemarkupRule' => 'applications/files/markup/PhabricatorImageRemarkupRule.php',
     'PhabricatorImageTransformer' => 'applications/files/PhabricatorImageTransformer.php',
     'PhabricatorImagemagickSetupCheck' => 'applications/config/check/PhabricatorImagemagickSetupCheck.php',
     'PhabricatorInFlightErrorView' => 'applications/config/view/PhabricatorInFlightErrorView.php',
@@ -7523,6 +7524,7 @@ phutil_register_library_map(array(
     'PhabricatorIconSetEditField' => 'PhabricatorEditField',
     'PhabricatorIconSetIcon' => 'Phobject',
     'PhabricatorImageMacroRemarkupRule' => 'PhutilRemarkupRule',
+    'PhabricatorImageRemarkupRule' => 'PhutilRemarkupRule',
     'PhabricatorImageTransformer' => 'Phobject',
     'PhabricatorImagemagickSetupCheck' => 'PhabricatorSetupCheck',
     'PhabricatorInFlightErrorView' => 'AphrontView',

src/applications/files/application/PhabricatorFilesApplication.php

@@ -37,6 +37,7 @@ final class PhabricatorFilesApplication extends PhabricatorApplication {
   public function getRemarkupRules() {
     return array(
       new PhabricatorEmbedFileRemarkupRule(),
+      new PhabricatorImageRemarkupRule(),
     );
   }
 

src/applications/files/markup/PhabricatorImageRemarkupRule.php

@@ -0,0 +1,75 @@
+<?php
+
+final class PhabricatorImageRemarkupRule extends PhutilRemarkupRule {
+  public function getPriority() {
+    return 200.0;
+  }
+
+  public function apply($text) {
+    return preg_replace_callback(
+      '@{(image|img) ((?:[^}\\\\]+|\\\\.)*)}@m',
+      array($this, 'markupImage'),
+      $text);
+  }
+
+  public function markupImage(array $matches) {
+    if (!$this->isFlatText($matches[0])) {
+      return $matches[0];
+    }
+    $args = array();
+    $defaults = array(
+      'uri' => null,
+      'alt' => null,
+      'href' => null,
+      'width' => null,
+      'height' => null,
+    );
+    $trimmed_match = trim($matches[2]);
+    if ($this->isURI($trimmed_match)) {
+      $args['uri'] = new PhutilURI($trimmed_match);
+    } else {
+      $parser = new PhutilSimpleOptions();
+      $keys = $parser->parse($trimmed_match);
+
+      $uri_key = '';
+      foreach (array('src', 'uri', 'url') as $key) {
+        if (array_key_exists($key, $keys)) {
+          $uri_key = $key;
+        }
+      }
+      if ($uri_key) {
+        $args['uri'] = new PhutilURI($keys[$uri_key]);
+      }
+      $args += $keys;
+    }
+
+    $args += $defaults;
+
+    if ($args['href'] && !PhabricatorEnv::isValidURIForLink($args['href'])) {
+      $args['href'] = null;
+    }
+
+    if ($args['uri']) {
+      $src_uri = id(new PhutilURI('/file/imageproxy/'))
+        ->setQueryParam('uri', (string)$args['uri']);
+      $img = $this->newTag(
+        'img',
+        array(
+          'src' => $src_uri,
+          'alt' => $args['alt'],
+          'href' => $args['href'],
+          'width' => $args['width'],
+          'height' => $args['height'],
+          ));
+      return $this->getEngine()->storeText($img);
+    } else {
+      return $matches[0];
+    }
+  }
+
+  private function isURI($uri_string) {
+    // Very simple check to make sure it starts with either http or https.
+    // If it does, we'll try to treat it like a valid URI
+    return preg_match('~^https?\:\/\/.*\z~i', $uri_string);
+  }
+}