<?php
/**
 * Zend Framework
 *
 * LICENSE
 *
 * This source file is subject to the new BSD license that is bundled
 * with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://framework.zend.com/license/new-bsd
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@zend.com so we can send you a copy immediately.
 *
 * @category   Zend
 * @package    Zend_Loader
 * @copyright  Copyright (c) 2005-2012 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 */

// Grab SplAutoloader interface
require_once dirname(__FILE__) . '/SplAutoloader.php';

/**
 * Class-map autoloader
 *
 * Utilizes class-map files to lookup classfile locations.
 * 
 * @package    Zend_Loader
 * @copyright  Copyright (c) 2005-2012 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    New BSD {@link http://framework.zend.com/license/new-bsd}
 */
class Zend_Loader_ClassMapAutoloader implements Zend_Loader_SplAutoloader
{
    /**
     * Registry of map files that have already been loaded
     * @var array
     */
    protected $mapsLoaded = array();

    /**
     * Class name/filename map
     * @var array
     */
    protected $map = array();

    /**
     * Constructor
     *
     * Create a new instance, and optionally configure the autoloader.
     * 
     * @param  null|array|Traversable $options 
     * @return void
     */
    public function __construct($options = null)
    {
        if (null !== $options) {
            $this->setOptions($options);
        }
    }

    /**
     * Configure the autoloader
     *
     * Proxies to {@link registerAutoloadMaps()}.
     * 
     * @param  array|Traversable $options 
     * @return Zend_Loader_ClassMapAutoloader
     */
    public function setOptions($options)
    {
        $this->registerAutoloadMaps($options);
        return $this;
    }

    /**
     * Register an autoload map
     *
     * An autoload map may be either an associative array, or a file returning
     * an associative array.
     *
     * An autoload map should be an associative array containing 
     * classname/file pairs.
     * 
     * @param  string|array $location 
     * @return Zend_Loader_ClassMapAutoloader
     */
    public function registerAutoloadMap($map)
    {
        if (is_string($map)) {
            $location = $map;
            if ($this === ($map = $this->loadMapFromFile($location))) {
                return $this;
            }
        }

        if (!is_array($map)) {
            require_once dirname(__FILE__) . '/Exception/InvalidArgumentException.php';
            throw new Zend_Loader_Exception_InvalidArgumentException('Map file provided does not return a map');
        }

        $this->map = array_merge($this->map, $map);

        if (isset($location)) {
            $this->mapsLoaded[] = $location;
        }

        return $this;
    }

    /**
     * Register many autoload maps at once
     * 
     * @param  array $locations 
     * @return Zend_Loader_ClassMapAutoloader
     */
    public function registerAutoloadMaps($locations)
    {
        if (!is_array($locations) && !($locations instanceof Traversable)) {
            require_once dirname(__FILE__) . '/Exception/InvalidArgumentException.php';
            throw new Zend_Loader_Exception_InvalidArgumentException('Map list must be an array or implement Traversable');
        }
        foreach ($locations as $location) {
            $this->registerAutoloadMap($location);
        }
        return $this;
    }

    /**
     * Retrieve current autoload map
     * 
     * @return array
     */
    public function getAutoloadMap()
    {
        return $this->map;
    }

    /**
     * Defined by Autoloadable
     * 
     * @param  string $class 
     * @return void
     */
    public function autoload($class)
    {
        if (isset($this->map[$class])) {
            require_once $this->map[$class];
        }
    }

    /**
     * Register the autoloader with spl_autoload registry
     * 
     * @return void
     */
    public function register()
    {
        if (version_compare(PHP_VERSION, '5.3.0', '>=')) {
            spl_autoload_register(array($this, 'autoload'), true, true);
        } else {
            spl_autoload_register(array($this, 'autoload'), true);
        }
    }

    /**
     * Load a map from a file
     *
     * If the map has been previously loaded, returns the current instance;
     * otherwise, returns whatever was returned by calling include() on the
     * location.
     * 
     * @param  string $location 
     * @return Zend_Loader_ClassMapAutoloader|mixed
     * @throws Zend_Loader_Exception_InvalidArgumentException for nonexistent locations
     */
    protected function loadMapFromFile($location)
    {
        if (!file_exists($location)) {
            require_once dirname(__FILE__) . '/Exception/InvalidArgumentException.php';
            throw new Zend_Loader_Exception_InvalidArgumentException('Map file provided does not exist');
        }

        if (!$path = self::realPharPath($location)) {
            $path = realpath($location);
        }

        if (in_array($path, $this->mapsLoaded)) {
            // Already loaded this map
            return $this;
        }

        $map = include $path;

        return $map;
    }

    /**
     * Resolve the real_path() to a file within a phar.
     *
     * @see    https://bugs.php.net/bug.php?id=52769 
     * @param  string $path 
     * @return string
     */
    public static function realPharPath($path)
    {
        if (strpos($path, 'phar:///') !== 0) {
            return;
        }
        
        $parts = explode('/', str_replace(array('/','\\'), '/', substr($path, 8)));
        $parts = array_values(array_filter($parts, array(__CLASS__, 'concatPharParts')));

        array_walk($parts, array(__CLASS__, 'resolvePharParentPath'), $parts);

        if (file_exists($realPath = 'phar:///' . implode('/', $parts))) {
            return $realPath;
        }
    }

    /**
     * Helper callback for filtering phar paths
     * 
     * @param  string $part 
     * @return bool
     */
    public static function concatPharParts($part)
    {
        return ($part !== '' && $part !== '.');
    }

    /**
     * Helper callback to resolve a parent path in a Phar archive
     * 
     * @param  string $value 
     * @param  int $key 
     * @param  array $parts 
     * @return void
     */
    public static function resolvePharParentPath($value, $key, &$parts)
    {
        if ($value !== '...') {
            return;
        }
        unset($parts[$key], $parts[$key-1]);
        $parts = array_values($parts);
    }
}
