Chris@0: <?php
Chris@0: 
Chris@0: /*
Chris@0:  * This file is part of the Mink package.
Chris@0:  * (c) Konstantin Kudryashov <ever.zet@gmail.com>
Chris@0:  *
Chris@0:  * For the full copyright and license information, please view the LICENSE
Chris@0:  * file that was distributed with this source code.
Chris@0:  */
Chris@0: 
Chris@0: namespace Behat\Mink\Selector\Xpath;
Chris@0: 
Chris@0: /**
Chris@0:  * XPath manipulation utility.
Chris@0:  *
Chris@0:  * @author Graham Bates
Chris@0:  * @author Christophe Coevoet <stof@notk.org>
Chris@0:  */
Chris@0: class Manipulator
Chris@0: {
Chris@0:     /**
Chris@0:      * Regex to find union operators not inside brackets.
Chris@0:      */
Chris@0:     const UNION_PATTERN = '/\|(?![^\[]*\])/';
Chris@0: 
Chris@0:     /**
Chris@0:      * Prepends the XPath prefix to the given XPath.
Chris@0:      *
Chris@0:      * The returned XPath will match elements matching the XPath inside an element
Chris@0:      * matching the prefix.
Chris@0:      *
Chris@0:      * @param string $xpath
Chris@0:      * @param string $prefix
Chris@0:      *
Chris@0:      * @return string
Chris@0:      */
Chris@0:     public function prepend($xpath, $prefix)
Chris@0:     {
Chris@0:         $expressions = array();
Chris@0: 
Chris@0:         // If the xpath prefix contains a union we need to wrap it in parentheses.
Chris@0:         if (preg_match(self::UNION_PATTERN, $prefix)) {
Chris@0:             $prefix = '('.$prefix.')';
Chris@0:         }
Chris@0: 
Chris@0:         // Split any unions into individual expressions.
Chris@0:         foreach ($this->splitUnionParts($xpath) as $expression) {
Chris@0:             $expression = trim($expression);
Chris@0:             $parenthesis = '';
Chris@0: 
Chris@0:             // If the union is inside some braces, we need to preserve the opening braces and apply
Chris@0:             // the prefix only inside it.
Chris@0:             if (preg_match('/^[\(\s*]+/', $expression, $matches)) {
Chris@0:                 $parenthesis = $matches[0];
Chris@0:                 $expression = substr($expression, strlen($parenthesis));
Chris@0:             }
Chris@0: 
Chris@0:             // add prefix before element selector
Chris@0:             if (0 === strpos($expression, '/')) {
Chris@0:                 $expression = $prefix.$expression;
Chris@0:             } else {
Chris@0:                 $expression = $prefix.'/'.$expression;
Chris@0:             }
Chris@0:             $expressions[] = $parenthesis.$expression;
Chris@0:         }
Chris@0: 
Chris@0:         return implode(' | ', $expressions);
Chris@0:     }
Chris@0: 
Chris@0:     /**
Chris@0:      * Splits the XPath into parts that are separated by the union operator.
Chris@0:      *
Chris@0:      * @param string $xpath
Chris@0:      *
Chris@0:      * @return string[]
Chris@0:      */
Chris@0:     private function splitUnionParts($xpath)
Chris@0:     {
Chris@0:         if (false === strpos($xpath, '|')) {
Chris@0:             return array($xpath); // If there is no pipe in the string, we know for sure that there is no union
Chris@0:         }
Chris@0: 
Chris@0:         $xpathLen = strlen($xpath);
Chris@0:         $openedBrackets = 0;
Chris@0:         // Consume whitespaces chars at the beginning of the string (this is the list of chars removed by trim() by default)
Chris@0:         $startPosition = strspn($xpath, " \t\n\r\0\x0B");
Chris@0: 
Chris@0:         $unionParts = array();
Chris@0: 
Chris@0:         for ($i = $startPosition; $i <= $xpathLen; ++$i) {
Chris@0:             // Consume all chars until we reach a quote, a bracket or a pipe
Chris@0:             $i += strcspn($xpath, '"\'[]|', $i);
Chris@0: 
Chris@0:             if ($i < $xpathLen) {
Chris@0:                 switch ($xpath[$i]) {
Chris@0:                     case '"':
Chris@0:                     case "'":
Chris@0:                         // Move to the end of the string literal
Chris@0:                         if (false === $i = strpos($xpath, $xpath[$i], $i + 1)) {
Chris@0:                             return array($xpath); // The XPath expression is invalid, don't split it
Chris@0:                         }
Chris@0:                         continue 2;
Chris@0:                     case '[':
Chris@0:                         ++$openedBrackets;
Chris@0:                         continue 2;
Chris@0:                     case ']':
Chris@0:                         --$openedBrackets;
Chris@0:                         continue 2;
Chris@0:                 }
Chris@0:             }
Chris@0:             if ($openedBrackets) {
Chris@0:                 continue;
Chris@0:             }
Chris@0: 
Chris@0:             $unionParts[] = substr($xpath, $startPosition, $i - $startPosition);
Chris@0: 
Chris@0:             if ($i === $xpathLen) {
Chris@0:                 return $unionParts;
Chris@0:             }
Chris@0: 
Chris@0:             // Consume any whitespace chars after the pipe
Chris@0:             $i += strspn($xpath, " \t\n\r\0\x0B", $i + 1);
Chris@0:             $startPosition = $i + 1;
Chris@0:         }
Chris@0: 
Chris@0:         return array($xpath); // The XPath expression is invalid
Chris@0:     }
Chris@0: 
Chris@0: }