Clean up Phabricator interface to syntax highlighting

Summary: Reduce the amount of code duplication here and allow for an override
configuration on the filename.map stuff.
Test Plan: Checked paste, diffusion and differential syntax highlighting and
everything appeared reasonable.
Reviewed By: codeblock
Reviewers: tuomaspelkonen, codeblock, jungejason, aran
CC: aran, codeblock, epriestley
Differential Revision: 601

src/applications/markup/syntax/PhabricatorSyntaxHighlighter.php

@@ -0,0 +1,51 @@
+<?php
+
+/*
+ * Copyright 2011 Facebook, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * @group markup
+ */
+final class PhabricatorSyntaxHighlighter {
+
+  public static function newEngine() {
+    $engine = new PhutilDefaultSyntaxHighlighterEngine();
+
+    $config = array(
+      'pygments.enabled' => PhabricatorEnv::getEnvConfig('pygments.enabled'),
+      'filename.map'     => PhabricatorEnv::getEnvConfig('syntax.filemap'),
+    );
+
+    foreach ($config as $key => $value) {
+      $engine->setConfig($key, $value);
+    }
+
+    return $engine;
+  }
+
+  public static function highlightWithFilename($filename, $source) {
+    $engine = self::newEngine();
+    $language = $engine->getLanguageFromFilename($filename);
+    return $engine->getHighlightFuture($language, $source)->resolve();
+  }
+
+  public static function highlightWithLanguage($language, $source) {
+    $engine = self::newEngine();
+    return $engine->getHighlightFuture($language, $source)->resolve();
+  }
+
+
+}