<?php



/*

 * This file is part of Composer.

 *

 * (c) Nils Adermann <naderman@naderman.de>

 *     Jordi Boggiano <j.boggiano@seld.be>

 *

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

 * file that was distributed with this source code.

 */



namespace Composer\Autoload;



/**

 * ClassLoader implements a PSR-0, PSR-4 and classmap class loader.

 *

 *     $loader = new \Composer\Autoload\ClassLoader();

 *

 *     // register classes with namespaces

 *     $loader->add('Symfony\Component', __DIR__.'/component');

 *     $loader->add('Symfony',           __DIR__.'/framework');

 *

 *     // activate the autoloader

 *     $loader->register();

 *

 *     // to enable searching the include path (eg. for PEAR packages)

 *     $loader->setUseIncludePath(true);

 *

 * 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.

 *

 * This class is loosely based on the Symfony UniversalClassLoader.

 *

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

 * @author Jordi Boggiano <j.boggiano@seld.be>

 * @see    http://www.php-fig.org/psr/psr-0/

 * @see    http://www.php-fig.org/psr/psr-4/

 */

class ClassLoader

{

    // PSR-4

    private $prefixLengthsPsr4 = array();

    private $prefixDirsPsr4 = array();

    private $fallbackDirsPsr4 = array();



    // PSR-0

    private $prefixesPsr0 = array();

    private $fallbackDirsPsr0 = array();



    private $useIncludePath = false;

    private $classMap = array();

    private $classMapAuthoritative = false;

    private $missingClasses = array();

    private $apcuPrefix;



    public function getPrefixes()

    {

        if (!empty($this->prefixesPsr0)) {

            return call_user_func_array('array_merge', $this->prefixesPsr0);

        }



        return array();

    }



    public function getPrefixesPsr4()

    {

        return $this->prefixDirsPsr4;

    }



    public function getFallbackDirs()

    {

        return $this->fallbackDirsPsr0;

    }



    public function getFallbackDirsPsr4()

    {

        return $this->fallbackDirsPsr4;

    }



    public function getClassMap()

    {

        return $this->classMap;

    }



    /**

     * @param array $classMap Class to filename map

     */

    public function addClassMap(array $classMap)

    {

        if ($this->classMap) {

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

        } else {

            $this->classMap = $classMap;

        }

    }



    /**

     * Registers a set of PSR-0 directories for a given prefix, either

     * appending or prepending to the ones previously set for this prefix.

     *

     * @param string       $prefix  The prefix

     * @param array|string $paths   The PSR-0 root directories

     * @param bool         $prepend Whether to prepend the directories

     */

    public function add($prefix, $paths, $prepend = false)

    {

        if (!$prefix) {

            if ($prepend) {

                $this->fallbackDirsPsr0 = array_merge(

                    (array) $paths,

                    $this->fallbackDirsPsr0

                );

            } else {

                $this->fallbackDirsPsr0 = array_merge(

                    $this->fallbackDirsPsr0,

                    (array) $paths

                );

            }



            return;

        }



        $first = $prefix[0];

        if (!isset($this->prefixesPsr0[$first][$prefix])) {

            $this->prefixesPsr0[$first][$prefix] = (array) $paths;



            return;

        }

        if ($prepend) {

            $this->prefixesPsr0[$first][$prefix] = array_merge(

                (array) $paths,

                $this->prefixesPsr0[$first][$prefix]

            );

        } else {

            $this->prefixesPsr0[$first][$prefix] = array_merge(

                $this->prefixesPsr0[$first][$prefix],

                (array) $paths

            );

        }

    }



    /**

     * Registers a set of PSR-4 directories for a given namespace, either

     * appending or prepending to the ones previously set for this namespace.

     *

     * @param string       $prefix  The prefix/namespace, with trailing '\\'

     * @param array|string $paths   The PSR-4 base directories

     * @param bool         $prepend Whether to prepend the directories

     *

     * @throws \InvalidArgumentException

     */

    public function addPsr4($prefix, $paths, $prepend = false)

    {

        if (!$prefix) {

            // Register directories for the root namespace.

            if ($prepend) {

                $this->fallbackDirsPsr4 = array_merge(

                    (array) $paths,

                    $this->fallbackDirsPsr4

                );

            } else {

                $this->fallbackDirsPsr4 = array_merge(

                    $this->fallbackDirsPsr4,

                    (array) $paths

                );

            }

        } elseif (!isset($this->prefixDirsPsr4[$prefix])) {

            // Register directories for a new namespace.

            $length = strlen($prefix);

            if ('\\' !== $prefix[$length - 1]) {

                throw new \InvalidArgumentException("A non-empty PSR-4 prefix must end with a namespace separator.");

            }

            $this->prefixLengthsPsr4[$prefix[0]][$prefix] = $length;

            $this->prefixDirsPsr4[$prefix] = (array) $paths;

        } elseif ($prepend) {

            // Prepend directories for an already registered namespace.

            $this->prefixDirsPsr4[$prefix] = array_merge(

                (array) $paths,

                $this->prefixDirsPsr4[$prefix]

            );

        } else {

            // Append directories for an already registered namespace.

            $this->prefixDirsPsr4[$prefix] = array_merge(

                $this->prefixDirsPsr4[$prefix],

                (array) $paths

            );

        }

    }



    /**

     * Registers a set of PSR-0 directories for a given prefix,

     * replacing any others previously set for this prefix.

     *

     * @param string       $prefix The prefix

     * @param array|string $paths  The PSR-0 base directories

     */

    public function set($prefix, $paths)

    {

        if (!$prefix) {

            $this->fallbackDirsPsr0 = (array) $paths;

        } else {

            $this->prefixesPsr0[$prefix[0]][$prefix] = (array) $paths;

        }

    }



    /**

     * Registers a set of PSR-4 directories for a given namespace,

     * replacing any others previously set for this namespace.

     *

     * @param string       $prefix The prefix/namespace, with trailing '\\'

     * @param array|string $paths  The PSR-4 base directories

     *

     * @throws \InvalidArgumentException

     */

    public function setPsr4($prefix, $paths)

    {

        if (!$prefix) {

            $this->fallbackDirsPsr4 = (array) $paths;

        } else {

            $length = strlen($prefix);

            if ('\\' !== $prefix[$length - 1]) {

                throw new \InvalidArgumentException("A non-empty PSR-4 prefix must end with a namespace separator.");

            }

            $this->prefixLengthsPsr4[$prefix[0]][$prefix] = $length;

            $this->prefixDirsPsr4[$prefix] = (array) $paths;

        }

    }



    /**

     * Turns on searching the include path for class files.

     *

     * @param bool $useIncludePath

     */

    public function setUseIncludePath($useIncludePath)

    {

        $this->useIncludePath = $useIncludePath;

    }



    /**

     * Can be used to check if the autoloader uses the include path to check

     * for classes.

     *

     * @return bool

     */

    public function getUseIncludePath()

    {

        return $this->useIncludePath;

    }



    /**

     * Turns off searching the prefix and fallback directories for classes

     * that have not been registered with the class map.

     *

     * @param bool $classMapAuthoritative

     */

    public function setClassMapAuthoritative($classMapAuthoritative)

    {

        $this->classMapAuthoritative = $classMapAuthoritative;

    }



    /**

     * Should class lookup fail if not found in the current class map?

     *

     * @return bool

     */

    public function isClassMapAuthoritative()

    {

        return $this->classMapAuthoritative;

    }



    /**

     * APCu prefix to use to cache found/not-found classes, if the extension is enabled.

     *

     * @param string|null $apcuPrefix

     */

    public function setApcuPrefix($apcuPrefix)

    {

        $this->apcuPrefix = function_exists('apcu_fetch') && filter_var(ini_get('apc.enabled'), FILTER_VALIDATE_BOOLEAN) ? $apcuPrefix : null;

    }



    /**

     * The APCu prefix in use, or null if APCu caching is not enabled.

     *

     * @return string|null

     */

    public function getApcuPrefix()

    {

        return $this->apcuPrefix;

    }



    /**

     * Registers this instance as an autoloader.

     *

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

     */

    public function register($prepend = false)

    {

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

    }



    /**

     * Unregisters this instance as an autoloader.

     */

    public function unregister()

    {

        spl_autoload_unregister(array($this, 'loadClass'));

    }



    /**

     * Loads the given class or interface.

     *

     * @param  string    $class The name of the class

     * @return bool|null True if loaded, null otherwise

     */

    public function loadClass($class)

    {

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

            includeFile($file);



            return true;

        }

    }



    /**

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

     *

     * @param string $class The name of the class

     *

     * @return string|false The path if found, false otherwise

     */

    public function findFile($class)

    {

        // class map lookup

        if (isset($this->classMap[$class])) {

            return $this->classMap[$class];

        }

        if ($this->classMapAuthoritative || isset($this->missingClasses[$class])) {

            return false;

        }

        if (null !== $this->apcuPrefix) {

            $file = apcu_fetch($this->apcuPrefix.$class, $hit);

            if ($hit) {

                return $file;

            }

        }



        $file = $this->findFileWithExtension($class, '.php');



        // Search for Hack files if we are running on HHVM

        if (false === $file && defined('HHVM_VERSION')) {

            $file = $this->findFileWithExtension($class, '.hh');

        }



        if (null !== $this->apcuPrefix) {

            apcu_add($this->apcuPrefix.$class, $file);

        }



        if (false === $file) {

            // Remember that this class does not exist.

            $this->missingClasses[$class] = true;

        }



        return $file;

    }



    private function findFileWithExtension($class, $ext)

    {

        // PSR-4 lookup

        $logicalPathPsr4 = strtr($class, '\\', DIRECTORY_SEPARATOR) . $ext;



        $first = $class[0];

        if (isset($this->prefixLengthsPsr4[$first])) {

            $subPath = $class;

            while (false !== $lastPos = strrpos($subPath, '\\')) {

                $subPath = substr($subPath, 0, $lastPos);

                $search = $subPath . '\\';

                if (isset($this->prefixDirsPsr4[$search])) {

                    $pathEnd = DIRECTORY_SEPARATOR . substr($logicalPathPsr4, $lastPos + 1);

                    foreach ($this->prefixDirsPsr4[$search] as $dir) {

                        if (file_exists($file = $dir . $pathEnd)) {

                            return $file;

                        }

                    }

                }

            }

        }



        // PSR-4 fallback dirs

        foreach ($this->fallbackDirsPsr4 as $dir) {

            if (file_exists($file = $dir . DIRECTORY_SEPARATOR . $logicalPathPsr4)) {

                return $file;

            }

        }



        // PSR-0 lookup

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

            // namespaced class name

            $logicalPathPsr0 = substr($logicalPathPsr4, 0, $pos + 1)

                . strtr(substr($logicalPathPsr4, $pos + 1), '_', DIRECTORY_SEPARATOR);

        } else {

            // PEAR-like class name

            $logicalPathPsr0 = strtr($class, '_', DIRECTORY_SEPARATOR) . $ext;

        }



        if (isset($this->prefixesPsr0[$first])) {

            foreach ($this->prefixesPsr0[$first] as $prefix => $dirs) {

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

                    foreach ($dirs as $dir) {

                        if (file_exists($file = $dir . DIRECTORY_SEPARATOR . $logicalPathPsr0)) {

                            return $file;

                        }

                    }

                }

            }

        }



        // PSR-0 fallback dirs

        foreach ($this->fallbackDirsPsr0 as $dir) {

            if (file_exists($file = $dir . DIRECTORY_SEPARATOR . $logicalPathPsr0)) {

                return $file;

            }

        }



        // PSR-0 include paths.

        if ($this->useIncludePath && $file = stream_resolve_include_path($logicalPathPsr0)) {

            return $file;

        }



        return false;

    }

}



/**

 * Scope isolated include.

 *

 * Prevents access to $this/self from included files.

 */

function includeFile($file)

{

    include $file;

}

