<?php

class Qs_Navigation
{
    protected static $_navigation = null;
    protected static $_buildNavigation = null;
    protected static $_defaultNavigation = null;
    protected static $_isEnabled = null;
    protected static $_config = null;
    protected static $_defaultConfig = array(
        'enabled'     => false,
        'mode'        => 'exclude',
        'properties'  => array('title' => 'menuTitle', 'url' => 'url'),
        'excludeList' => array(array(array('isRoot' => 'y'))),
    );

    public static function isEnabled()
    {
        if (null === Qs_Navigation::$_isEnabled) {
            Qs_Navigation::$_isEnabled = Qs_Navigation::_getConfig('enabled');
        }
        return Qs_Navigation::$_isEnabled;
    }

    public static function clean()
    {
        $nav = Qs_Navigation::$_navigation;
        Qs_Navigation::$_navigation = null;
        return $nav;
    }

    /**
     * Allows to show the breadcrumb navigation on the page
     *
     * @return  bool Old Value
     */
    public static function enable()
    {
        $oldValue = Qs_Navigation::$_isEnabled;
        Qs_Navigation::$_isEnabled = true;
        return $oldValue;
    }

    /**
     * Disallows to show the breadcrumb navigation on the page
     *
     * @return  bool Old Value
     */
    public static function disable()
    {
        $oldValue = Qs_Navigation::$_isEnabled;
        Qs_Navigation::$_isEnabled = false;
        return $oldValue;
    }

    /**
     * Set navigation that will be displayed on the page,
     * Optional param $enable allows/disallows to show navigation on the page
     *
     * @param array $nav
     * @param bool $enable
     * @return bool
     * @throws Qs_Exception
     */
    public static function set($nav, $enable = null)
    {
        if (!empty($nav) && is_array($nav)) {
            $nav = (is_array(reset($nav))) ? $nav : array($nav);
            $oldNav = Qs_Navigation::$_navigation;
            Qs_Navigation::$_navigation = $nav;
            if (null !== $enable) {
                if (is_bool($enable)) {
                    Qs_Navigation::$_isEnabled = $enable;
                } else {
                    throw new Qs_Exception('Invalid $enable parameter given in Qs_Navigation');
                }
            }
            return $oldNav;
        } else {
            throw new Qs_Exception('Invalid $nav parameter given in Qs_Navigation');
        }
    }

    /**
     * Returns breadcrumbs for current page (including config rules, changes made by
     * function Qs_Navigation::set(), Qs_Navigation::append()).
     * Parameter "$properties" sets page properties that will be returned (default: 'title'=>'menuTitle', 'url'=>'url').
     *
     * @param   array   $properties
     * @return  array
     * @throws Qs_Exception
     */
    public static function get($properties = null)
    {
        if (null !== $properties && !is_array($properties)) {
            throw new Qs_Exception('Invalid $properties parameter given in Qs_Navigation');
        }
        if (null !== Qs_Navigation::$_navigation) {
            $nav = Qs_Navigation::$_navigation;
        } else {
            $nav = Qs_Navigation::build();
            Qs_Navigation::$_navigation = $nav;
        }
        if (null !== $properties && null !== $nav) {
            foreach ($nav as $key => $page) {
                $nav[$key] = Qs_Navigation::_processPage($page, $properties);
            }
        }
        return $nav;
    }

    /**
     * Appends/Prepends $breadcrumbs to the $target (if given), or Qs_Navigation::get().
     * Returns navigation.
     * Function does not affect the output of navigation on the page. Use Qs_Navigation::append() instead.
     *
     * @param   array   $breadcrumbs
     * @param   string  $mode
     * @param   array   $target
     * @return array
     * @throws Qs_Exception
     */
    public static function getAppend($breadcrumbs, $mode = 'append', $target = null)
    {

        if (!is_array($breadcrumbs)) {
            throw new Qs_Exception('Invalid $breadcrumbs parameter in Qs_Navigation');
        }
        if (null == $target) {
            $target = Qs_Navigation::get();
            if (null === $target) {
                return null;
            }
        } elseif (!is_array($target)) {
            throw new Qs_Exception('Invalid $target parameter given in Qs_Navigation');
        }
        $breadcrumbs = (is_array(reset($breadcrumbs))) ? $breadcrumbs : array($breadcrumbs);
        if ('append' == $mode) {
            foreach ($breadcrumbs as $item) {
                array_push($target, $item);
            }
        } else {
            $breadcrumbs = array_reverse($breadcrumbs);
            foreach ($breadcrumbs as $item) {
                array_unshift($target, $item);
            }
        }
        return $target;
    }

    /**
     *  Appends/Prepends $breadcrumbs to the default navigation and retuns it
     *
     * @param   array   $breadcrumbs
     * @param   string  $mode
     * @return array
     */
    public static function append($breadcrumbs, $mode = 'append')
    {
        Qs_Navigation::$_navigation = Qs_Navigation::getAppend($breadcrumbs, $mode);
        return Qs_Navigation::$_navigation;
    }

    /**
     * Returns breadcrumb navigation based on SiteMap and Config rules
     *
     * @return array
     * @throws Qs_Exception
     */
    public static function build()
    {
        if (null !== Qs_Navigation::$_buildNavigation) {
            return Qs_Navigation::$_buildNavigation;
        }
        $config = Qs_Navigation::_getConfig();
        $mode = $config['mode'];
        if (!isset($config['mode'])
            || !method_exists('Qs_Navigation', '_check' . ucfirst($mode) . 'Rules')
            || !isset($config['properties']) || !is_array($config['properties'])
            || (isset($config['prepend']) && !is_array($config['prepend']))
            || (isset($config['append']) && !is_array($config['append']))
            || !isset($config[$mode.'List'])
        ) {
                throw new Qs_Exception('Invalid config given in Qs_Navigation::getNavigation()');
        }
        $navigation = null;
        if (call_user_func(array('Qs_Navigation', '_check' . ucfirst($mode).'Rules'), $config[$mode . 'List'])) {
            $navigation = Qs_Navigation::_getDefault($config['properties']);
            if (isset($config['prepend'])) {
                $navigation = Qs_Navigation::getAppend($config['prepend'], 'prepend', $navigation);
            }
            if (isset($config['append'])) {
                $navigation = Qs_Navigation::getAppend($config['append'], 'append', $navigation);
            }
        }
        Qs_Navigation::$_buildNavigation = (empty($navigation)) ? null : $navigation;
        return Qs_Navigation::$_buildNavigation;
    }

    protected static function _isBackEndArea()
    {
        return (0 === strpos(CURRENT_PAGE_FINAL, 'admin/'));
    }

    /**
     * Returns default breadcrumbs navigation based on SiteMap (not including config rules)
     *
     * @param   array   $properties
     * @return  array
     */
    protected static function _getDefault($properties = array())
    {
        if (null !== Qs_Navigation::$_defaultNavigation
            && (empty($properties) || ($properties == Qs_Navigation::_getConfig('properties')))) {
                return Qs_Navigation::$_defaultNavigation;
        }
        $nav = $tree = array();
        $subUrl = Qs_Constant::get('CURRENT_PAGE_FINAL');
        $properties = (empty($properties)) ? Qs_Navigation::_getConfig('properties') : $properties;
        $parts = explode('/', trim($subUrl, '/'));
        if (Qs_Navigation::_isBackEndArea()) {
            $tree = Qs_SiteMap::getBackendSiteMapFull();
        } else {
            $tree = Qs_SiteMap::getFromDb();
            $firstPage = reset($tree);
            if ('y' != $firstPage['isRoot']
                && !in_array(reset($parts), array('', $firstPage['alias']))
                && null !== ($sub = Qs_Navigation::_processPage($firstPage, $properties))
            ) {
                    $nav[] = $sub;
            }
        }
        foreach ($parts as $alias) {
            if (array_key_exists($alias, $tree)) {
                $nav[] = Qs_Navigation::_processPage($tree[$alias], $properties);
                if (isset($tree[$alias]['sub'])) {
                    $tree = $tree[$alias]['sub'];
                } else {
                    break;
                }
            } else {
                break;
            }
        }
        if (empty($properties) || ($properties == Qs_Navigation::_getConfig('properties'))) {
            Qs_Navigation::$_defaultNavigation = (empty($nav)) ? null : $nav;
        }
        return (empty($nav)) ? null : $nav;
    }

    protected static function _checkIncludeRules($includeList)
    {
        $page = Qs_SiteMap::getPage(CURRENT_PAGE);
        if (!is_array($page) || empty($page)) {
            return false;
        }
        $includeList = (is_array($includeList)) ? $includeList : array($includeList);
        foreach ($includeList as $rule) {
            if (is_int($rule)) {
                if ($rule == $page['id']) {
                    return true;
                }
            } elseif (is_string($rule)) {
                if ($rule == $page['fullAlias']) {
                    return true;
                }
            } elseif (is_array($rule)) {
                if (true == Qs_Navigation::_checkPageQuery($page, $rule)) {
                    return true;
                }
            } else {
                throw new Qs_Exception('Invalid $includeList parameter given in Qs_Navigation');
            }
        }
        return false;
    }

    protected static function _checkExcludeRules($excludeList)
    {
        $page = Qs_SiteMap::getPage(CURRENT_PAGE);
        if (!is_array($page) || empty($page)) {
            return true;
        }
        $excludeList = (is_array($excludeList)) ? $excludeList : array($excludeList);
        foreach ($excludeList as $rule) {
            if (is_int($rule)) {
                if ($rule == $page['id']) {
                    return false;
                }
            } elseif (is_string($rule)) {
                if ($rule == $page['fullAlias']) {
                    return false;
                }
            } elseif (is_array($rule)) {
                if (true == Qs_Navigation::_checkPageQuery($page, $rule)) {
                    return false;
                }
            } else {
                throw new Qs_Exception('Invalid $excludeList parameter given in Qs_Navigation');
            }
        }
        return true;
    }

    public static function _processPage($page, $properties)
    {
        if (!isset($page) || !is_array($page)) {
            return null;
        }
        $part = array();
        foreach ($properties as $name => $prop) {
            $name = (is_string($name)) ? $name : $prop;
            if (isset($page[$prop])) {
                $part[$name] = $page[$prop];
            }
        }

        // якщо елемент редірект на сторінку на якій ми знаходимось, то не виводимо лінк для цього елемента
        if ($page['redirect'] == 'y' && $page['redirectType'] == 'page') {
            $doc = Zend_Registry::get('doc');
            if ($page['redirectPageId'] == $doc->getOption('id')) {
                $part['url'] = '';
            }
        }

        return $part;
    }

    protected static function _getConfig($field = null)
    {
        if (null === Qs_Navigation::$_config) {
            $config = Qs_Config::get(basename(__FILE__, '.php'), Qs_Config::QS_TYPE)->toArray();
            if (empty($config)) {
                throw new Qs_Exception('config is not found');
            }
            $configPath = (Qs_Navigation::_isBackEndArea()) ? 'admin' : NULL;
            Qs_Navigation::$_config = Qs_Array::get($config, $configPath, Qs_Navigation::$_defaultConfig);
        }
        return (null === $field) ? Qs_Navigation::$_config : Qs_Array::get(Qs_Navigation::$_config, $field);
    }

    protected static function _checkPageQuery($page, $rule)
    {
        $_page = array_shift($rule)   or $_page = array();
        $_item = array_shift($rule)   or $_item = array();
        $_config = array_shift($rule) or $_config = array();

        $diff = array_diff_assoc($_page, $page);
        if (empty($diff)) {
            if (!isset($page['items'])) {
                $page['items'] = array();
            }
            foreach ($page['items'] as &$item) {
                $diff = array_diff_assoc($_item, $item);
                if (empty($diff)) {
                    $config = Qs_Array::get($item, 'config', array());
                    $diff = array_diff_assoc($_config, $config);
                    if (empty($diff)) {
                        return true;
                    }
                }
            }
        }
        return false;
    }
}