/pdepend/PHP/Depend/Metrics/AnalyzerClassFileSystemLocator.php

<?php
/**
 * This file is part of PHP_Depend.
 *
 * PHP Version 5
 *
 * Copyright (c) 2008-2010, Manuel Pichler <mapi@pdepend.org>.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   * Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *   * Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in
 *     the documentation and/or other materials provided with the
 *     distribution.
 *
 *   * Neither the name of Manuel Pichler nor the names of his
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 * @category   QualityAssurance
 * @package    PHP_Depend
 * @subpackage Metrics
 * @author     Manuel Pichler <mapi@pdepend.org>
 * @copyright  2008-2010 Manuel Pichler. All rights reserved.
 * @license    http://www.opensource.org/licenses/bsd-license.php  BSD License
 * @version    SVN: $Id$
 * @link       http://pdepend.org/
 * @since      0.9.10
 */

require_once 'PHP/Depend/Metrics/AnalyzerClassLocator.php';

/**
 * Locator that searches for PHP_Depend analyzers that follow the PHP_Depend
 * convention and are present the PHP_Depend source tree.
 *
 * @category   QualityAssurance
 * @package    PHP_Depend
 * @subpackage Metrics
 * @author     Manuel Pichler <mapi@pdepend.org>
 * @copyright  2008-2010 Manuel Pichler. All rights reserved.
 * @license    http://www.opensource.org/licenses/bsd-license.php  BSD License
 * @version    Release: @package_version@
 * @link       http://pdepend.org/
 * @since      0.9.10
 */
class PHP_Depend_Metrics_AnalyzerClassFileSystemLocator
    implements PHP_Depend_Metrics_AnalyzerClassLocator
{
    /**
     * The root search directory.
     *
     * @var string
     */
    private $_classPath = null;

    /**
     * Array containing reflection classes for all found analyzer implementations.
     *
     * @var array(ReflectionClass)
     */
    private $_analyzers = null;

    /**
     * Regular expression that matches possible analyzer source files.
     *
     * @var string
     */
    private $_classRegexp = '(Metrics[/\\\\][a-zA-Z0-9_]+[/\\\\]Analyzer\.php$)';

    /**
     * Constructs a new locator instance.
     *
     * @param string $classPath The root search directory.
     */
    public function __construct($classPath = null)
    {
        if ($classPath === null) {
            $classPath = dirname(__FILE__) . '/../../../';
        }
        $this->_classPath = realpath($classPath) . DIRECTORY_SEPARATOR;
    }

    /**
     * Returns an array with reflection instances for all analyzer classes.
     *
     * @return array(ReflectionClass)
     */
    public function findAll()
    {
        if ($this->_analyzers === null) {
            $this->_analyzers = $this->_find();
        }
        return $this->_analyzers;
    }

    /**
     * Performs a recursive search for analyzers in the configured class path
     * directory.
     *
     * @return array(ReflectionClass)
     */
    private function _find()
    {
        $result = array();

        $paths = explode(PATH_SEPARATOR, get_include_path());

        foreach ($paths as $path) {
            $dir = $path.'/PHP/Depend/Metrics/';

            if (!is_dir($dir)) {
                continue;
            }

            $this->_classPath = $dir;

            $iterator = new RecursiveIteratorIterator(
                new RecursiveDirectoryIterator($dir)
            );

            foreach ($iterator as $file) {
                if ($file->getFilename() === 'Analyzer.php') {
                    $className = $this->_createClassNameFromPath(
                        $dir, $file->getPathname()
                    );
                    if (!class_exists($className)) {
                        include_once $file->getPathname();
                    }

                    if ($this->_isAnalyzerClass($className)) {
                        $result[$className] = new ReflectionClass($className);
                    }
                }
            }
        }
        
        ksort($result);
        return array_values($result);
    }

    /**
     * Creates a possible analyzer class name from a given absolute file path
     * name.
     *
     * @param string $classPath The currently processed class path.
     * @param string $path      Path of a possible analyzer class.
     *
     * @return string
     */
    private function _createClassNameFromPath($classPath, $path)
    {
        $localPath = substr($path, strlen($classPath), -4);
        return 'PHP_Depend_Metrics_' . strtr($localPath, DIRECTORY_SEPARATOR, '_');
    }

    /**
     * Checks if the given class name represents a valid analyzer implementation.
     *
     * @param string $className Class name of a possible analyzer implementation.
     *
     * @return boolean
     */
    private function _isAnalyzerClass($className)
    {
        return class_exists($className) && $this->_implementsInterface($className);
    }

    /**
     * Checks if the given class implements the analyzer interface.
     *
     * @param string $className Class name of a possible analyzer implementation.
     *
     * @return boolean
     */
    private function _implementsInterface($className)
    {
        $expectedType = 'PHP_Depend_Metrics_AnalyzerI';
        return in_array($expectedType, class_implements($className));
    }
}