<?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\Bridge\Twig\Extension;

use Symfony\Bridge\Twig\TokenParser\FormThemeTokenParser;

use Symfony\Component\Form\FormView;

use Symfony\Component\Form\Exception\FormException;

use Symfony\Component\Form\Util\FormUtil;

/**

 * FormExtension extends Twig with form capabilities.

 *

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

 * @author Bernhard Schussek <bernhard.schussek@symfony.com>

 */

class FormExtension extends \Twig_Extension

{

    protected $resources;

    protected $blocks;

    protected $environment;

    protected $themes;

    protected $varStack;

    protected $template;

    public function __construct(array $resources = array())

    {

        $this->themes = new \SplObjectStorage();

        $this->varStack = array();

        $this->blocks = new \SplObjectStorage();

        $this->resources = $resources;

    }

    /**

     * {@inheritdoc}

     */

    public function initRuntime(\Twig_Environment $environment)

    {

        $this->environment = $environment;

    }

    /**

     * Sets a theme for a given view.

     *

     * @param FormView $view      A FormView instance

     * @param array    $resources An array of resources

     */

    public function setTheme(FormView $view, array $resources)

    {

        $this->themes->attach($view, $resources);

        $this->blocks = new \SplObjectStorage();

    }

    /**

     * Returns the token parser instance to add to the existing list.

     *

     * @return array An array of Twig_TokenParser instances

     */

    public function getTokenParsers()

    {

        return array(

            // {% form_theme form "SomeBungle::widgets.twig" %}

            new FormThemeTokenParser(),

        );

    }

    public function getFunctions()

    {

        return array(

            'form_enctype'             => new \Twig_Function_Method($this, 'renderEnctype', array('is_safe' => array('html'))),

            'form_widget'              => new \Twig_Function_Method($this, 'renderWidget', array('is_safe' => array('html'))),

            'form_errors'              => new \Twig_Function_Method($this, 'renderErrors', array('is_safe' => array('html'))),

            'form_label'               => new \Twig_Function_Method($this, 'renderLabel', array('is_safe' => array('html'))),

            'form_row'                 => new \Twig_Function_Method($this, 'renderRow', array('is_safe' => array('html'))),

            'form_rest'                => new \Twig_Function_Method($this, 'renderRest', array('is_safe' => array('html'))),

            '_form_is_choice_group'    => new \Twig_Function_Method($this, 'isChoiceGroup', array('is_safe' => array('html'))),

            '_form_is_choice_selected' => new \Twig_Function_Method($this, 'isChoiceSelected', array('is_safe' => array('html'))),

        );

    }

    public function isChoiceGroup($label)

    {

        return FormUtil::isChoiceGroup($label);

    }

    public function isChoiceSelected(FormView $view, $choice)

    {

        return FormUtil::isChoiceSelected($choice, $view->get('value'));

    }

    /**

     * Renders the HTML enctype in the form tag, if necessary

     *

     * Example usage in Twig templates:

     *

     *     <form action="..." method="post" {{ form_enctype(form) }}>

     *

     * @param FormView $view  The view for which to render the encoding type

     *

     * @return string The html markup

     */

    public function renderEnctype(FormView $view)

    {

        return $this->render($view, 'enctype');

    }

    /**

     * Renders a row for the view.

     *

     * @param FormView $view      The view to render as a row

     * @param array    $variables An array of variables

     *

     * @return string The html markup

     */

    public function renderRow(FormView $view, array $variables = array())

    {

        return $this->render($view, 'row', $variables);

    }

    /**

     * Renders views which have not already been rendered.

     *

     * @param FormView $view      The parent view

     * @param array    $variables An array of variables

     *

     * @return string The html markup

     */

    public function renderRest(FormView $view, array $variables = array())

    {

        return $this->render($view, 'rest', $variables);

    }

    /**

     * Renders the HTML for a given view

     *

     * Example usage in Twig:

     *

     *     {{ form_widget(view) }}

     *

     * You can pass options during the call:

     *

     *     {{ form_widget(view, {'attr': {'class': 'foo'}}) }}

     *

     *     {{ form_widget(view, {'separator': '+++++'}) }}

     *

     * @param FormView        $view      The view to render

     * @param array           $variables Additional variables passed to the template

     *

     * @return string The html markup

     */

    public function renderWidget(FormView $view, array $variables = array())

    {

        return $this->render($view, 'widget', $variables);

    }

    /**

     * Renders the errors of the given view

     *

     * @param FormView $view The view to render the errors for

     *

     * @return string The html markup

     */

    public function renderErrors(FormView $view)

    {

        return $this->render($view, 'errors');

    }

    /**

     * Renders the label of the given view

     *

     * @param FormView $view  The view to render the label for

     * @param string   $label Label name

     * @param array    $variables Additional variables passed to the template

     *

     * @return string The html markup

     */

    public function renderLabel(FormView $view, $label = null, array $variables = array())

    {

        if ($label !== null) {

            $variables += array('label' => $label);

        }

        return $this->render($view, 'label', $variables);

    }

    /**

     * Renders a template.

     *

     * 1. This function first looks for a block named "_<view id>_<section>",

     * 2. if such a block is not found the function will look for a block named

     *    "<type name>_<section>",

     * 3. the type name is recursively replaced by the parent type name until a

     *    corresponding block is found

     *

     * @param FormView  $view       The form view

     * @param string    $section    The section to render (i.e. 'row', 'widget', 'label', ...)

     * @param array     $variables  Additional variables

     *

     * @return string The html markup

     *

     * @throws FormException if no template block exists to render the given section of the view

     */

    protected function render(FormView $view, $section, array $variables = array())

    {

        $mainTemplate = in_array($section, array('widget', 'row'));

        if ($mainTemplate && $view->isRendered()) {

                return '';

        }

        if (null === $this->template) {

            $this->template = reset($this->resources);

            if (!$this->template instanceof \Twig_Template) {

                $this->template = $this->environment->loadTemplate($this->template);

            }

        }

        $custom = '_'.$view->get('id');

        $rendering = $custom.$section;

        $blocks = $this->getBlocks($view);

        if (isset($this->varStack[$rendering])) {

            $typeIndex = $this->varStack[$rendering]['typeIndex'] - 1;

            $types = $this->varStack[$rendering]['types'];

            $this->varStack[$rendering]['variables'] = array_replace_recursive($this->varStack[$rendering]['variables'], $variables);

        } else {

            $types = $view->get('types');

            $types[] = $custom;

            $typeIndex = count($types) - 1;

            $this->varStack[$rendering] = array (

                'variables' => array_replace_recursive($view->all(), $variables),

                'types'     => $types,

            );

        }

        do {

            $types[$typeIndex] .= '_'.$section;

            if (isset($blocks[$types[$typeIndex]])) {

                $this->varStack[$rendering]['typeIndex'] = $typeIndex;

                // we do not call renderBlock here to avoid too many nested level calls (XDebug limits the level to 100 by default)

                ob_start();

                $this->template->displayBlock($types[$typeIndex], $this->varStack[$rendering]['variables'], $blocks);

                $html = ob_get_clean();

                if ($mainTemplate) {

                    $view->setRendered();

                }

                unset($this->varStack[$rendering]);

                return $html;

            }

        } while (--$typeIndex >= 0);

        throw new FormException(sprintf(

            'Unable to render the form as none of the following blocks exist: "%s".',

            implode('", "', array_reverse($types))

        ));

    }

    /**

     * Returns the name of the extension.

     *

     * @return string The extension name

     */

    public function getName()

    {

        return 'form';

    }

    /**

     * Returns the blocks used to render the view.

     *

     * Templates are looked for in the resources in the following order:

     *   * resources from the themes (and its parents)

     *   * resources from the themes of parent views (up to the root view)

     *   * default resources

     *

     * @param FormView $view The view

     *

     * @return array An array of Twig_TemplateInterface instances

     */

    protected function getBlocks(FormView $view)

    {

        if (!$this->blocks->contains($view)) {

            $rootView = !$view->hasParent();

            $templates = $rootView ? $this->resources : array();

            if (isset($this->themes[$view])) {

                $templates = array_merge($templates, $this->themes[$view]);

            }

            $blocks = array();

            foreach ($templates as $template) {

                if (!$template instanceof \Twig_Template) {

                    $template = $this->environment->loadTemplate($template);

                }

                $templateBlocks = array();

                do {

                    $templateBlocks = array_merge($template->getBlocks(), $templateBlocks);

                } while (false !== $template = $template->getParent(array()));

                $blocks = array_merge($blocks, $templateBlocks);

            }

            if (!$rootView) {

                $blocks = array_merge($this->getBlocks($view->getParent()), $blocks);

            }

            $this->blocks->attach($view, $blocks);

        } else {

            $blocks = $this->blocks[$view];

        }

        return $blocks;

    }

}