<?php

/*
 * This file is part of the Symfony framework.
 *
 * (c) Fabien Potencier <fabien@symfony.com>
 *
 * This source file is subject to the MIT license that is bundled
 * with this source code in the file LICENSE.
 */

namespace Symfony\Bundle\AsseticBundle\Templating;

use Assetic\Asset\AssetInterface;
use Assetic\Factory\AssetFactory;
use Assetic\Util\TraversableString;
use Symfony\Component\Templating\Helper\Helper;

/**
 * The "assetic" templating helper.
 *
 * @author Kris Wallsmith <kris@symfony.com>
 */
abstract class AsseticHelper extends Helper
{
    protected $factory;

    /**
     * Constructor.
     *
     * @param AssetFactory $factory The asset factory
     */
    public function __construct(AssetFactory $factory)
    {
        $this->factory = $factory;
    }

    /**
     * Returns an array of javascript urls.
     */
    public function javascripts($inputs = array(), $filters = array(), array $options = array())
    {
        if (!isset($options['output'])) {
            $options['output'] = 'js/*.js';
        }

        return $this->getAssetUrls($inputs, $filters, $options);
    }

    /**
     * Returns an array of stylesheet urls.
     */
    public function stylesheets($inputs = array(), $filters = array(), array $options = array())
    {
        if (!isset($options['output'])) {
            $options['output'] = 'css/*.css';
        }

        return $this->getAssetUrls($inputs, $filters, $options);
    }

    /**
     * Returns an array of one image url.
     */
    public function image($inputs = array(), $filters = array(), array $options = array())
    {
        if (!isset($options['output'])) {
            $options['output'] = 'images/*';
        }

        $options['single'] = true;

        return $this->getAssetUrls($inputs, $filters, $options);
    }

    /**
     * Gets the URLs for the configured asset.
     *
     * Usage looks something like this:
     *
     *     <?php foreach ($view['assetic']->assets('@jquery, js/src/core/*', '?yui_js') as $url): ?>
     *         <script src="<?php echo $url ?>" type="text/javascript"></script>
     *     <?php endforeach; ?>
     *
     * When in debug mode, the helper returns an array of one or more URLs.
     * When not in debug mode it returns an array of one URL.
     *
     * @param array|string $inputs  An array or comma-separated list of input strings
     * @param array|string $filters An array or comma-separated list of filter names
     * @param array        $options An array of options
     *
     * @return array An array of URLs for the asset
     */
    private function getAssetUrls($inputs = array(), $filters = array(), array $options = array())
    {
        $explode = function ($value) {
            return array_map('trim', explode(',', $value));
        };

        if (!is_array($inputs)) {
            $inputs = $explode($inputs);
        }

        if (!is_array($filters)) {
            $filters = $explode($filters);
        }

        if (!isset($options['debug'])) {
            $options['debug'] = $this->factory->isDebug();
        }

        if (!isset($options['combine'])) {
            $options['combine'] = !$options['debug'];
        }

        if (isset($options['single']) && $options['single'] && 1 < count($inputs)) {
            $inputs = array_slice($inputs, -1);
        }

        if (!isset($options['name'])) {
            $options['name'] = $this->factory->generateAssetName($inputs, $filters, $options);
        }

        $asset = $this->factory->createAsset($inputs, $filters, $options);

        $one = $this->getAssetUrl($asset, $options);
        $many = array();
        if ($options['combine']) {
            $many[] = $one;
        } else {
            $i = 0;
            foreach ($asset as $leaf) {
                $many[] = $this->getAssetUrl($leaf, array_replace($options, array(
                    'name' => $options['name'].'_'.$i++,
                )));
            }
        }

        return new TraversableString($one, $many);
    }

    /**
     * Returns an URL for the supplied asset.
     *
     * @param AssetInterface $asset   An asset
     * @param array          $options An array of options
     *
     * @return string An echo-ready URL
     */
    abstract protected function getAssetUrl(AssetInterface $asset, $options = array());

    public function getName()
    {
        return 'assetic';
    }
}
