Primo Committ

vendor/league/commonmark/src/Util/LinkParserHelper.php

@@ -0,0 +1,125 @@
+<?php
+
+/*
+ * This file is part of the league/commonmark package.
+ *
+ * (c) Colin O'Dell <colinodell@gmail.com>
+ *
+ * Original code based on the CommonMark JS reference parser (https://bitly.com/commonmark-js)
+ *  - (c) John MacFarlane
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace League\CommonMark\Util;
+
+use League\CommonMark\Cursor;
+
+final class LinkParserHelper
+{
+    /**
+     * Attempt to parse link destination
+     *
+     * @param Cursor $cursor
+     *
+     * @return null|string The string, or null if no match
+     */
+    public static function parseLinkDestination(Cursor $cursor): ?string
+    {
+        if ($res = $cursor->match(RegexHelper::REGEX_LINK_DESTINATION_BRACES)) {
+            // Chop off surrounding <..>:
+            return UrlEncoder::unescapeAndEncode(
+                RegexHelper::unescape(\substr($res, 1, -1))
+            );
+        }
+
+        if ($cursor->getCharacter() === '<') {
+            return null;
+        }
+
+        $destination = self::manuallyParseLinkDestination($cursor);
+        if ($destination === null) {
+            return null;
+        }
+
+        return UrlEncoder::unescapeAndEncode(
+            RegexHelper::unescape($destination)
+        );
+    }
+
+    public static function parseLinkLabel(Cursor $cursor): int
+    {
+        $match = $cursor->match('/^\[(?:[^\\\\\[\]]|\\\\.){0,1000}\]/');
+        if ($match === null) {
+            return 0;
+        }
+
+        $length = \mb_strlen($match, 'utf-8');
+
+        if ($length > 1001) {
+            return 0;
+        }
+
+        return $length;
+    }
+
+    /**
+     * Attempt to parse link title (sans quotes)
+     *
+     * @param Cursor $cursor
+     *
+     * @return null|string The string, or null if no match
+     */
+    public static function parseLinkTitle(Cursor $cursor): ?string
+    {
+        if ($title = $cursor->match('/' . RegexHelper::PARTIAL_LINK_TITLE . '/')) {
+            // Chop off quotes from title and unescape
+            return RegexHelper::unescape(\substr($title, 1, -1));
+        }
+
+        return null;
+    }
+
+    private static function manuallyParseLinkDestination(Cursor $cursor): ?string
+    {
+        $oldPosition = $cursor->getPosition();
+        $oldState = $cursor->saveState();
+
+        $openParens = 0;
+        while (($c = $cursor->getCharacter()) !== null) {
+            if ($c === '\\' && $cursor->peek() !== null && RegexHelper::isEscapable($cursor->peek())) {
+                $cursor->advanceBy(2);
+            } elseif ($c === '(') {
+                $cursor->advanceBy(1);
+                $openParens++;
+            } elseif ($c === ')') {
+                if ($openParens < 1) {
+                    break;
+                }
+
+                $cursor->advanceBy(1);
+                $openParens--;
+            } elseif (\preg_match(RegexHelper::REGEX_WHITESPACE_CHAR, $c)) {
+                break;
+            } else {
+                $cursor->advanceBy(1);
+            }
+        }
+
+        if ($openParens !== 0) {
+            return null;
+        }
+
+        if ($cursor->getPosition() === $oldPosition && $c !== ')') {
+            return null;
+        }
+
+        $newPos = $cursor->getPosition();
+        $cursor->restoreState($oldState);
+
+        $cursor->advanceBy($newPos - $cursor->getPosition());
+
+        return $cursor->getPreviousText();
+    }
+}