<?php

/*

 * This file is part of Twig.

 *

 * (c) 2009 Fabien Potencier

 *

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

 * file that was distributed with this source code.

 */

/**

 * Loads template from the filesystem.

 *

 * @package    twig

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

 */

class Twig_Loader_Filesystem implements Twig_LoaderInterface

{

    protected $paths;

    protected $cache;

    /**

     * Constructor.

     *

     * @param string|array $paths A path or an array of paths where to look for templates

     */

    public function __construct($paths)

    {

        $this->setPaths($paths);

    }

    /**

     * Returns the paths to the templates.

     *

     * @return array The array of paths where to look for templates

     */

    public function getPaths()

    {

        return $this->paths;

    }

    /**

     * Sets the paths where templates are stored.

     *

     * @param string|array $paths A path or an array of paths where to look for templates

     */

    public function setPaths($paths)

    {

        if (!is_array($paths)) {

            $paths = array($paths);

        }

        $this->paths = array();

        foreach ($paths as $path) {

            $this->addPath($path);

        }

    }

    /**

     * Adds a path where templates are stored.

     *

     * @param string $path A path where to look for templates

     */

    public function addPath($path)

    {

        // invalidate the cache

        $this->cache = array();

        if (!is_dir($path)) {

            throw new Twig_Error_Loader(sprintf('The "%s" directory does not exist.', $path));

        }

        $this->paths[] = $path;

    }

    /**

     * Gets the source code of a template, given its name.

     *

     * @param  string $name The name of the template to load

     *

     * @return string The template source code

     */

    public function getSource($name)

    {

        return file_get_contents($this->findTemplate($name));

    }

    /**

     * Gets the cache key to use for the cache for a given template name.

     *

     * @param  string $name The name of the template to load

     *

     * @return string The cache key

     */

    public function getCacheKey($name)

    {

        return $this->findTemplate($name);

    }

    /**

     * Returns true if the template is still fresh.

     *

     * @param string    $name The template name

     * @param timestamp $time The last modification time of the cached template

     */

    public function isFresh($name, $time)

    {

        return filemtime($this->findTemplate($name)) < $time;

    }

    protected function findTemplate($name)

    {

        // normalize name

        $name = preg_replace('#/{2,}#', '/', strtr($name, '\\', '/'));

        if (isset($this->cache[$name])) {

            return $this->cache[$name];

        }

        $this->validateName($name);

        foreach ($this->paths as $path) {

            if (is_file($path.'/'.$name)) {

                return $this->cache[$name] = $path.'/'.$name;

            }

        }

        throw new Twig_Error_Loader(sprintf('Unable to find template "%s" (looked into: %s).', $name, implode(', ', $this->paths)));

    }

    protected function validateName($name)

    {

        if (false !== strpos($name, "\0")) {

            throw new Twig_Error_Loader('A template name cannot contain NUL bytes.');

        }

        $parts = explode('/', $name);

        $level = 0;

        foreach ($parts as $part) {

            if ('..' === $part) {

                --$level;

            } elseif ('.' !== $part) {

                ++$level;

            }

            if ($level < 0) {

                throw new Twig_Error_Loader(sprintf('Looks like you try to load a template outside configured directories (%s).', $name));

            }

        }

    }

}