<?php

/*

 * This file is part of the Symfony package.

 *

 * (c) Fabien Potencier <fabien@symfony.com>

 *

 * For the full copyright and license information, please view the LICENSE

 * file that was distributed with this source code.

 */

namespace Symfony\Component\ClassLoader;

/**

 * UniversalClassLoader implements a "universal" autoloader for PHP 5.3.

 *

 * It is able to load classes that use either:

 *

 *  * The technical interoperability standards for PHP 5.3 namespaces and

 *    class names (http://groups.google.com/group/php-standards/web/psr-0-final-proposal);

 *

 *  * The PEAR naming convention for classes (http://pear.php.net/).

 *

 * Classes from a sub-namespace or a sub-hierarchy of PEAR classes can be

 * looked for in a list of locations to ease the vendoring of a sub-set of

 * classes for large projects.

 *

 * Example usage:

 *

 *     $loader = new UniversalClassLoader();

 *

 *     // register classes with namespaces

 *     $loader->registerNamespaces(array(

 *         'Symfony\Component' => __DIR__.'/component',

 *         'Symfony'           => __DIR__.'/framework',

 *         'Sensio'            => array(__DIR__.'/src', __DIR__.'/vendor'),

 *     ));

 *

 *     // register a library using the PEAR naming convention

 *     $loader->registerPrefixes(array(

 *         'Swift_' => __DIR__.'/Swift',

 *     ));

 *

 *     // activate the autoloader

 *     $loader->register();

 *

 * In this example, if you try to use a class in the Symfony\Component

 * namespace or one of its children (Symfony\Component\Console for instance),

 * the autoloader will first look for the class under the component/

 * directory, and it will then fallback to the framework/ directory if not

 * found before giving up.

 *

 * @author Fabien Potencier <fabien@symfony.com>

 *

 * @api

 */

class UniversalClassLoader

{

    private $namespaces = array();

    private $prefixes = array();

    private $namespaceFallbacks = array();

    private $prefixFallbacks = array();

    /**

     * Gets the configured namespaces.

     *

     * @return array A hash with namespaces as keys and directories as values

     */

    public function getNamespaces()

    {

        return $this->namespaces;

    }

    /**

     * Gets the configured class prefixes.

     *

     * @return array A hash with class prefixes as keys and directories as values

     */

    public function getPrefixes()

    {

        return $this->prefixes;

    }

    /**

     * Gets the directory(ies) to use as a fallback for namespaces.

     *

     * @return array An array of directories

     */

    public function getNamespaceFallbacks()

    {

        return $this->namespaceFallbacks;

    }

    /**

     * Gets the directory(ies) to use as a fallback for class prefixes.

     *

     * @return array An array of directories

     */

    public function getPrefixFallbacks()

    {

        return $this->prefixFallbacks;

    }

    /**

     * Registers the directory to use as a fallback for namespaces.

     *

     * @param array $dirs An array of directories

     *

     * @api

     */

    public function registerNamespaceFallbacks(array $dirs)

    {

        $this->namespaceFallbacks = $dirs;

    }

    /**

     * Registers the directory to use as a fallback for class prefixes.

     *

     * @param array $dirs An array of directories

     *

     * @api

     */

    public function registerPrefixFallbacks(array $dirs)

    {

        $this->prefixFallbacks = $dirs;

    }

    /**

     * Registers an array of namespaces

     *

     * @param array $namespaces An array of namespaces (namespaces as keys and locations as values)

     *

     * @api

     */

    public function registerNamespaces(array $namespaces)

    {

        foreach ($namespaces as $namespace => $locations) {

            $this->namespaces[$namespace] = (array) $locations;

        }

    }

    /**

     * Registers a namespace.

     *

     * @param string       $namespace The namespace

     * @param array|string $paths     The location(s) of the namespace

     *

     * @api

     */

    public function registerNamespace($namespace, $paths)

    {

        $this->namespaces[$namespace] = (array) $paths;

    }

    /**

     * Registers an array of classes using the PEAR naming convention.

     *

     * @param array $classes An array of classes (prefixes as keys and locations as values)

     *

     * @api

     */

    public function registerPrefixes(array $classes)

    {

        foreach ($classes as $prefix => $locations) {

            $this->prefixes[$prefix] = (array) $locations;

        }

    }

    /**

     * Registers a set of classes using the PEAR naming convention.

     *

     * @param string       $prefix  The classes prefix

     * @param array|string $paths   The location(s) of the classes

     *

     * @api

     */

    public function registerPrefix($prefix, $paths)

    {

        $this->prefixes[$prefix] = (array) $paths;

    }

    /**

     * Registers this instance as an autoloader.

     *

     * @param Boolean $prepend Whether to prepend the autoloader or not

     *

     * @api

     */

    public function register($prepend = false)

    {

        spl_autoload_register(array($this, 'loadClass'), true, $prepend);

    }

    /**

     * Loads the given class or interface.

     *

     * @param string $class The name of the class

     */

    public function loadClass($class)

    {

        if ($file = $this->findFile($class)) {

            require $file;

        }

    }

    /**

     * Finds the path to the file where the class is defined.

     *

     * @param string $class The name of the class

     *

     * @return string|null The path, if found

     */

    public function findFile($class)

    {

        if ('\\' == $class[0]) {

            $class = substr($class, 1);

        }

        if (false !== $pos = strrpos($class, '\\')) {

            // namespaced class name

            $namespace = substr($class, 0, $pos);

            foreach ($this->namespaces as $ns => $dirs) {

                if (0 !== strpos($namespace, $ns)) {

                    continue;

                }

                foreach ($dirs as $dir) {

                    $className = substr($class, $pos + 1);

                    $file = $dir.DIRECTORY_SEPARATOR.str_replace('\\', DIRECTORY_SEPARATOR, $namespace).DIRECTORY_SEPARATOR.str_replace('_', DIRECTORY_SEPARATOR, $className).'.php';

                    if (file_exists($file)) {

                        return $file;

                    }

                }

            }

            foreach ($this->namespaceFallbacks as $dir) {

                $file = $dir.DIRECTORY_SEPARATOR.str_replace('\\', DIRECTORY_SEPARATOR, $class).'.php';

                if (file_exists($file)) {

                    return $file;

                }

            }

        } else {

            // PEAR-like class name

            foreach ($this->prefixes as $prefix => $dirs) {

                if (0 !== strpos($class, $prefix)) {

                    continue;

                }

                foreach ($dirs as $dir) {

                    $file = $dir.DIRECTORY_SEPARATOR.str_replace('_', DIRECTORY_SEPARATOR, $class).'.php';

                    if (file_exists($file)) {

                        return $file;

                    }

                }

            }

            foreach ($this->prefixFallbacks as $dir) {

                $file = $dir.DIRECTORY_SEPARATOR.str_replace('_', DIRECTORY_SEPARATOR, $class).'.php';

                if (file_exists($file)) {

                    return $file;

                }

            }

        }

    }

}