<?php

/**
 * Joomla! Content Management System
 *
 * @copyright  (C) 2016 Open Source Matters, Inc. <https://www.joomla.org>
 * @license    GNU General Public License version 2 or later; see LICENSE.txt
 */

namespace Joomla\CMS\Component\Router\Rules;

use Joomla\CMS\Component\ComponentHelper;
use Joomla\CMS\Component\Router\RouterView;
use Joomla\CMS\Language\Multilanguage;

// phpcs:disable PSR1.Files.SideEffects
\defined('JPATH_PLATFORM') or die;
// phpcs:enable PSR1.Files.SideEffects

/**
 * Rule to identify the right Itemid for a view in a component
 *
 * @since  3.4
 */
class MenuRules implements RulesInterface
{
    /**
     * Router this rule belongs to
     *
     * @var   RouterView
     * @since 3.4
     */
    protected $router;

    /**
     * Lookup array of the menu items
     *
     * @var   array
     * @since 3.4
     */
    protected $lookup = array();

    /**
     * Class constructor.
     *
     * @param   RouterView  $router  Router this rule belongs to
     *
     * @since   3.4
     */
    public function __construct(RouterView $router)
    {
        $this->router = $router;

        $this->buildLookup();
    }

    /**
     * Finds the right Itemid for this query
     *
     * @param   array  &$query  The query array to process
     *
     * @return  void
     *
     * @since   3.4
     */
    public function preprocess(&$query)
    {
        $active = $this->router->menu->getActive();

        /**
         * If the active item id is not the same as the supplied item id or we have a supplied item id and no active
         * menu item then we just use the supplied menu item and continue
         */
        if (isset($query['Itemid']) && ($active === null || $query['Itemid'] != $active->id)) {
            return;
        }

        // Get query language
        $language = isset($query['lang']) ? $query['lang'] : '*';

        // Set the language to the current one when multilang is enabled and item is tagged to ALL
        if (Multilanguage::isEnabled() && $language === '*') {
            $language = $this->router->app->get('language');
        }

        if (!isset($this->lookup[$language])) {
            $this->buildLookup($language);
        }

        // Check if the active menu item matches the requested query
        if ($active !== null && isset($query['Itemid'])) {
            // Check if active->query and supplied query are the same
            $match = true;

            foreach ($active->query as $k => $v) {
                if (isset($query[$k]) && $v !== $query[$k]) {
                    // Compare again without alias
                    if (\is_string($v) && $v == current(explode(':', $query[$k], 2))) {
                        continue;
                    }

                    $match = false;
                    break;
                }
            }

            if ($match) {
                // Just use the supplied menu item
                return;
            }
        }

        $needles = $this->router->getPath($query);

        $layout = isset($query['layout']) && $query['layout'] !== 'default' ? ':' . $query['layout'] : '';

        if ($needles) {
            foreach ($needles as $view => $ids) {
                $viewLayout = $view . $layout;

                if ($layout && isset($this->lookup[$language][$viewLayout])) {
                    if (\is_bool($ids)) {
                        $query['Itemid'] = $this->lookup[$language][$viewLayout];

                        return;
                    }

                    foreach ($ids as $id => $segment) {
                        if (isset($this->lookup[$language][$viewLayout][(int) $id])) {
                            $query['Itemid'] = $this->lookup[$language][$viewLayout][(int) $id];

                            return;
                        }
                    }
                }

                if (isset($this->lookup[$language][$view])) {
                    if (\is_bool($ids)) {
                        $query['Itemid'] = $this->lookup[$language][$view];

                        return;
                    }

                    foreach ($ids as $id => $segment) {
                        if (isset($this->lookup[$language][$view][(int) $id])) {
                            $query['Itemid'] = $this->lookup[$language][$view][(int) $id];

                            return;
                        }
                    }
                }
            }
        }

        // Check if the active menuitem matches the requested language
        if (
            $active && $active->component === 'com_' . $this->router->getName()
            && ($language === '*' || \in_array($active->language, array('*', $language)) || !Multilanguage::isEnabled())
        ) {
            $query['Itemid'] = $active->id;

            return;
        }

        // If not found, return language specific home link
        $default = $this->router->menu->getDefault($language);

        if (!empty($default->id)) {
            $query['Itemid'] = $default->id;
        }
    }

    /**
     * Method to build the lookup array
     *
     * @param   string  $language  The language that the lookup should be built up for
     *
     * @return  void
     *
     * @since   3.4
     */
    protected function buildLookup($language = '*')
    {
        // Prepare the reverse lookup array.
        if (!isset($this->lookup[$language])) {
            $this->lookup[$language] = array();

            $component  = ComponentHelper::getComponent('com_' . $this->router->getName());
            $views = $this->router->getViews();

            $attributes = array('component_id');
            $values     = array((int) $component->id);

            $attributes[] = 'language';
            $values[]     = array($language, '*');

            $items = $this->router->menu->getItems($attributes, $values);

            foreach ($items as $item) {
                if (isset($item->query['view'], $views[$item->query['view']])) {
                    $view = $item->query['view'];

                    $layout = '';

                    if (isset($item->query['layout'])) {
                        $layout = ':' . $item->query['layout'];
                    }

                    if ($views[$view]->key) {
                        if (!isset($this->lookup[$language][$view . $layout])) {
                            $this->lookup[$language][$view . $layout] = array();
                        }

                        if (!isset($this->lookup[$language][$view])) {
                            $this->lookup[$language][$view] = array();
                        }

                        // If menuitem has no key set, we assume 0.
                        if (!isset($item->query[$views[$view]->key])) {
                            $item->query[$views[$view]->key] = 0;
                        }

                        /**
                         * Here it will become a bit tricky
                         * language != * can override existing entries
                         * language == * cannot override existing entries
                         */
                        if (!isset($this->lookup[$language][$view . $layout][$item->query[$views[$view]->key]]) || $item->language !== '*') {
                            $this->lookup[$language][$view . $layout][$item->query[$views[$view]->key]] = $item->id;
                            $this->lookup[$language][$view][$item->query[$views[$view]->key]] = $item->id;
                        }
                    } else {
                        /**
                         * Here it will become a bit tricky
                         * language != * can override existing entries
                         * language == * cannot override existing entries
                         */
                        if (!isset($this->lookup[$language][$view . $layout]) || $item->language !== '*') {
                            $this->lookup[$language][$view . $layout] = $item->id;
                        }
                    }
                }
            }
        }
    }

    /**
     * Dummy method to fulfil the interface requirements
     *
     * @param   array  &$segments  The URL segments to parse
     * @param   array  &$vars      The vars that result from the segments
     *
     * @return  void
     *
     * @since   3.4
     * @codeCoverageIgnore
     */
    public function parse(&$segments, &$vars)
    {
    }

    /**
     * Dummy method to fulfil the interface requirements
     *
     * @param   array  &$query     The vars that should be converted
     * @param   array  &$segments  The URL segments to create
     *
     * @return  void
     *
     * @since   3.4
     * @codeCoverageIgnore
     */
    public function build(&$query, &$segments)
    {
    }
}