Xoops\Core\Psr4ClassLoader

Complexity

Total Complexity

16

Size/Duplication

Total Lines	169
Duplicated Lines	0 %

Coupling/Cohesion

Components	1
Dependencies	0

Test Coverage

Coverage

26.09%

Importance

Changes

0

6 Methods

Rating	Name	Duplication	Size	Complexity
A	addLoader()	0	14	3
A	register()	0	4	1
A	addNamespace()	0	21	3
A	requireFile()	0	10	2
B	loadClass()	0	28	3
B	loadMappedFile()	0	26	4

<?php
/**
 * Copyright (c) 2013 PHP Framework Interop Group
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

namespace Xoops\Core;

/**
 * A Class Loader that implements the technical interoperability
 * standards for PHP 5.3 namespaces and class names set forth in PSR-4.
 * This general-purpose implementation includes the optional functionality
 * of allowing multiple base directories for a single namespace prefix.
 *
 * From the PHP Framework Interop Group
 *
 * Examples
 *
 * Given a foo-bar package of classes in the file system at the following
 * paths ...
 *
 *     /path/to/packages/foo-bar/
 *         src/
 *             Baz.php             # Foo\Bar\Baz
 *             Qux/
 *                 Quux.php        # Foo\Bar\Qux\Quux
 *         tests/
 *             BazTest.php         # Foo\Bar\BazTest
 *             Qux/
 *                 QuuxTest.php    # Foo\Bar\Qux\QuuxTest
 *
 * ... add the path to the class files for the \Foo\Bar\ namespace prefix
 * as follows:
 *
 * @code
 *      <?php
 *      // instantiate the loader
 *      $loader = new \Xoops\Core\Psr4ClassLoader;
 *
 *      // register the autoloader
 *      $loader->register();
 *
 *      // register the base directories for the namespace prefix
 *      $loader->addNamespace('Foo\Bar', '/path/to/packages/foo-bar/src');
 *      $loader->addNamespace('Foo\Bar', '/path/to/packages/foo-bar/tests');
 * @endcode
 *
 * The following line would cause the autoloader to attempt to load the
 * \Foo\Bar\Qux\Quux class from /path/to/packages/foo-bar/src/Qux/Quux.php:
 *
 * @code
 *      <?php
 *      new \Foo\Bar\Qux\Quux;
 * @endcode
 *
 * The following line would cause the autoloader to attempt to load the
 * \Foo\Bar\Qux\QuuxTest class from /path/to/packages/foo-bar/tests/Qux/QuuxTest.php:
 *
 * @code
 *      <?php
 *      new \Foo\Bar\Qux\QuuxTest;
 * @endcode
 *
 * @category  Xoops\Core\Psr4ClassLoader
 * @package   Xoops
 * @author    https://github.com/php-fig/fig-standards/
 * @author    Richard Griffith <richard@geekwright.com>
 * @copyright 2013 PHP Framework Interop Group
 * @copyright 2013-2014 XOOPS Project (http://xoops.org)
 * @license   MIT (see above)
 * @link      https://github.com/php-fig/fig-standards/wiki/PSR-4-Example-Implementations
 * @see       http://www.php-fig.org/
 */
class Psr4ClassLoader
{
    /**
     * An associative array where the key is a namespace prefix and the value
     * is an array of base directories for classes in that namespace.
     *
     * @var array
     */
    protected $prefixes = array();

    /**
     * addLoader sets all basic options and registers the autoloader
     *
     * @param type  $namespace namespace
     * @param mixed $path      path(s) to the namespace's directories
     *                         Can be string - only one directory
     *                         or array of strings - multiple directories
     *
     * @return SplClassLoader
     */
    public static function addLoader($namespace, $path)
    {
        $loaderClass = get_called_class();
        $loader = new $loaderClass($namespace, $path);
        if (is_array($path)) {
            foreach ($path as $pathdir) {
                $loader->addNamespace($namespace, $pathdir);
            }
        } else {
            $loader->addNamespace($namespace, $path);
        }
        $loader->register();
        return $loader;
    }

    /**
     * Register loader with SPL autoloader stack.
     *
     * @return null
     */
    public function register()
    {
        spl_autoload_register(array($this, 'loadClass'));
    }

    /**
     * Adds a base directory for a namespace prefix.
     *
     * @param string $prefix   The namespace prefix.
     * @param string $base_dir Base directory for class files in namespace.
     * @param bool   $prepend  If true, prepend the base directory to the
     *                         stack instead of appending it; this causes
     *                         it to be searched first rather than last.
     *
     * @return null
     */
    public function addNamespace($prefix, $base_dir, $prepend = false)
    {
        // normalize namespace prefix
        $prefix = trim($prefix, '\\') . '\\';

        // normalize the base directory with a trailing separator
        $base_dir = rtrim($base_dir, '/') . DIRECTORY_SEPARATOR;
        $base_dir = rtrim($base_dir, DIRECTORY_SEPARATOR) . '/';

        // initialize the namespace prefix array
        if (isset($this->prefixes[$prefix]) === false) {
            $this->prefixes[$prefix] = array();
        }

        // retain the base directory for the namespace prefix
        if ($prepend) {
            array_unshift($this->prefixes[$prefix], $base_dir);
        } else {
            array_push($this->prefixes[$prefix], $base_dir);
        }
    }

    /**
     * Loads the class file for a given class name.
     *
     * @param string $class The fully-qualified class name.
     *
     * @return string|false  The mapped file name on success, or boolean false on
     * failure.
     */
    public function loadClass($class)
    {
        // the current namespace prefix
        $prefix = $class;

        // work backwards through the namespace names of the fully-qualified
        // class name to find a mapped file name
        while (false !== $pos = strrpos($prefix, '\\')) {
            // retain the trailing namespace separator in the prefix
            $prefix = substr($class, 0, $pos + 1);

            // the rest is the relative class name
            $relative_class = substr($class, $pos + 1);

            // try to load a mapped file for the prefix and relative class
            $mapped_file = $this->loadMappedFile($prefix, $relative_class);
            if ($mapped_file !== false) {
                return $mapped_file;
            }

            // remove the trailing namespace separator for the next iteration
            // of strrpos()
            $prefix = rtrim($prefix, '\\');
        }

        // never found a mapped file
        return false;
    }

    /**
     * Load the mapped file for a namespace prefix and relative class.
     *
     * @param string $prefix         The namespace prefix.
     * @param string $relative_class The relative class name.
     *
     * @return false|string  Boolean false if no mapped file can be loaded, or the
     * name of the mapped file that was loaded.
     */
    protected function loadMappedFile($prefix, $relative_class)
    {
        // are there any base directories for this namespace prefix?
        if (isset($this->prefixes[$prefix]) === false) {
            return false;
        }

        // look through base directories for this namespace prefix
        foreach ($this->prefixes[$prefix] as $base_dir) {
            // replace the namespace prefix with the base directory,
            // replace namespace separators with directory separators
            // in the relative class name, append with .php
            $file = $base_dir
                  . str_replace('\\', '/', $relative_class)
                  . '.php';

            // if the mapped file exists, require it
            if ($this->requireFile($file)) {
                // yes, we're done
                return $file;
            }
        }

        // never found it
        return false;
    }

    /**
     * If a file exists, require it from the file system.
     *
     * @param string $file The file to require.
     *
     * @return bool   True if the file exists, false if not.
     */
    protected function requireFile($file)
    {
        if (file_exists($file)) {
            require $file;

            return true;
        }

        return false;
    }
}