<?php


/**
 * Utility class for the Arlima plugin. Important that you don't use closures
 * or any other php features that isn't available in php 5.2 in this file
 */
class Arlima_Plugin {

    const VERSION = 2.2;
    const EXPORT_FEED_NAME = 'arlima-export';
    const STATIC_VERSION = '13.92211';

    private static $is_scissors_installed = null;
    private static $is_wp_related_post_installed = null;
    private static $has_loaded_textdomain = false;

    /**
     * Actions added in the theme
     */
    function initThemeActions() {
        add_action('init', array($this, 'commonInitHook'));
        add_action('init', array($this, 'themeInitHook'));
    }

    /**
     * Actions added in wp-admin
     */
    function initAdminActions() {
        add_action('init', array($this, 'commonInitHook'));
        add_action('init', array($this, 'adminInitHook'));
        add_action('admin_menu', array($this, 'adminMenu' ));
        add_action('admin_footer', array($this, 'warnAboutIncompatiblePHPVersion'));
        add_action('add_meta_boxes', array($this, 'addMetaBox') );
    }

    /**
     * function called on init in the theme
     */
    function themeInitHook() {
        $this->addTemplateCSS();
    }


    /**
     * If we get a lot of calls to this function we might as well always make a call
     * to load_plugin_textdomain on init, and not only in wp-admin
     *
     * @see Arlima_Plugin::loadTextDomain()
     * @static
     * @return bool
     */
    public static function loadTextDomain() {
        if( !self::$has_loaded_textdomain ) {
            self::$has_loaded_textdomain = true;
            load_plugin_textdomain('arlima', false, 'arlima/lang/');
        }
    }

    /**
     * Init hook taking place in both wp-admin and theme
     */
    function commonInitHook() {
        add_action('wp_before_admin_bar_render', function() {
            /* @var WP_Admin_Bar $wp_admin_bar */
            global $wp_admin_bar;
            if( is_admin_bar_showing() ) {
                Arlima_Plugin::loadTextDomain();
                $wp_admin_bar->add_menu( array(
                    'id' => 'arlima',
                    'parent' => '',
                    'title' => __( 'Article lists', 'arlima'),
                    'href' => admin_url( 'admin.php?page=arlima' )
                ) );
                foreach(Arlima_ListFactory::loadListSlugs() as $list_data) {
                    $wp_admin_bar->add_menu( array(
                        'id' => 'arlima-'.$list_data->id,
                        'parent' => 'arlima',
                        'title' => $list_data->title,
                        'href' => admin_url( 'admin.php?page=arlima&amp;open_list='.$list_data->id )
                    ) );
                }
            }
        });
        $this->addExportFeeds();
        self::$is_scissors_installed = function_exists('scissors_create_image');
        self::$is_wp_related_post_installed = function_exists('MRP_get_related_posts');

        // update publish date for arlima articles
        add_action('save_post', function($post_id) {
            if( !defined('DOING_AUTOSAVE') || !DOING_AUTOSAVE ) {
                Arlima_ListFactory::updateArlimaArticleData(get_post($post_id));
            }
        });
    }

    /**
     * Function called on init in wp-admin
     */
    function adminInitHook() {
        self::update();
        self::loadTextDomain();
    }

    /**
     * Adds arlima export feed to Wordpress
     */
    function addExportFeeds() {
        add_feed(self::EXPORT_FEED_NAME, array($this, 'loadExportFeed'));
    }

    /**
     * Install procedure for this plugin
     *  - Adds database tables
     *  - Adds version number in db
     *  - Adds arlima export feed and flushed wp_rewrite
     * @static
     */
    public static function install() {
        Arlima_ListFactory::install();
        global  $wp_rewrite;
        $plugin = new self();
        $plugin->addExportFeeds();
        $wp_rewrite->flush_rules();
        $plugin = new self();
        $settings = $plugin->loadSettings();
        $settings['install_version'] = self::VERSION;
        $plugin->saveSettings($settings);
    }

    /**
     * Uninstall procedure for this plugin
     *  - Removes plugin settings
     *  - Removes database tables
     * @static
     */
    public static function uninstall() {
        Arlima_ListFactory::uninstall();
        delete_option('arlima_plugin_settings');
    }

    /**
     * Deactivation procedure for this plugin
     *  - Removes feed from wp_rewrite
     * @static
     */
    public static function deactivate() {
        global $wp_rewrite;
        $feed_index = array_search('arlima', $wp_rewrite->feeds);
        if($feed_index) {
            array_splice($wp_rewrite->feeds, $feed_index, 1);
            $wp_rewrite->flush_rules();
        }
    }

    /**
     * Update procedure for this plugin. Since wordpress is lacking this feature we
     * should call this function on a regular basis.
     */
    public static function update() {
        $plugin = new self();
        $settings = $plugin->loadSettings();
        $current_version = isset($settings['install_version']) ? $settings['install_version'] : 0;

        // Time for update
        if($current_version != self::VERSION) {

            // Update to v 2.0
            if($current_version < 2) {
                global  $wp_rewrite;
                $plugin->addExportFeeds();
                $wp_rewrite->flush_rules();
            }

            // Update to version 2.2
            if($current_version < self::VERSION) {
                Arlima_ListFactory::databaseUpdates($current_version);
            }

            $settings['install_version'] = self::VERSION;
            $plugin->saveSettings($settings);
        }
    }

    /**
     * Will try to export arlima list from currently visited page
     */
    function loadExportFeed() {
        global $wp_query;
        $format = isset($_REQUEST['format']) ? $_REQUEST['format']:Arlima_ExportManager::DEFAULT_FORMAT;
        $page_slug = !empty($wp_query->query_vars['pagename']) ? $wp_query->query_vars['pagename'] : '';
        $export_manager = new Arlima_ExportManager($this);
        $export_manager->export($page_slug, $format);
        die;
    }

    /**
     * Settings of any kind related to this plugin
     * @return array
     */
    function loadSettings() {
        return get_option('arlima_plugin_settings', array());
    }

    /**
     * @param array $setting
     */
    function saveSettings(array $setting) {
        update_option('arlima_plugin_settings', $setting);
    }

    /**
     * Adds meta box to post edit/create page
     */
    function addMetaBox() {
        add_meta_box(
            'arlima-meta-box',
            'Arlima',
            array($this, 'postMetaBox'),
            'post',
            'side',
            'low'
        );
    }

    /**
     * Content of meta box used to send a wordpress post immediately from post
     * edit page in wp-admin to an arlima list
     */
    function postMetaBox() {
        global $post;

        wp_nonce_field( plugin_basename( __FILE__ ), 'vkuc_nonce' );

        if ( $post->post_status == 'publish' ) { ?>
            <input type="hidden" name="arlima-postid" id="arlima-postid" value="<?php echo $post->ID; ?>" />
            <select name="arlima-listid" id="arlima-listid">
                <option value=""><?php _e('Choose article list', 'arlima') ?></option>
                <?php foreach( Arlima_ListFactory::loadListSlugs() as $arlima_list ) { ?>
                    <option value="<?php echo $arlima_list->id; ?>"><?php echo $arlima_list->title; ?></option>
                <?php }	?>
            </select>
            <input id="arlima-send-to-list-btn" class="button-secondary action" type="button" name="arlima-send-to-list-btn" value="Skicka" /> <img src="<?php echo   ARLIMA_PLUGIN_URL . '/images/ajax-loader-trans.gif'; ?>" class="ajax-loader" style="display:none;" />
        <?php }else{
           echo '<em>'.__('Post needs to be published', 'arlima').'</em>';
        }
    }

    /**
     * This function will output a warning message if the server has
     * a PHP version lower than 5.3
     */
    function warnAboutIncompatiblePHPVersion() {
        $version_parts = explode('.', phpversion());
        $version = floatval($version_parts[0] .'.'. $version_parts[1]);
        if( $version < 5.3 ): ?>
        <div style="position: fixed; background-color:#EEE; background: rgba(255,255,255, .9); line-height: 140%; border: #FF0000 dashed 3px; z-index: 9999; top:40px; right:20px; padding: 20px; text-align: center">
            <p>
                <strong style="color:red; font-size: 300%;">WARNING</strong>
                <strong>
                    <br /><br /> You need to deactivate the plugin &quot;Arlima&quot;.<br />
                    The reason for this is that your server does<br /> not have a PHP installation of
                    version 5.3 or higher.
                </strong>
            </p>
        </div>
        <?php endif;
    }

    /**
     * Creates the menu in wp-admin for this plugin and then call Arlima_Plugin::addAdminPageScriptsAndStylesheets
     * that will add all javascript and stylesheets needed by this plugin in wp-admin
     */
    function adminMenu() {
        $arlima_mainpage = add_menu_page(__('Article List Manager', 'arlima'), __('Article lists', 'arlima'), 'edit_posts', 'arlima', 'Arlima_Plugin::loadAdminMainPage', ARLIMA_PLUGIN_URL . '/images/skull-icon.png');
        add_submenu_page('arlima', __('Article lists', 'arlima'), __('Manage lists', 'arlima'), 'edit_posts', 'arlima', 'Arlima_Plugin::loadAdminMainPage');
        $arlima_editpage = add_submenu_page('arlima', __('Edit lists', 'arlima'), __('Edit lists', 'arlima'), 'edit_posts', 'arlima-editpage', 'Arlima_Plugin::loadAdminEditPage' );
        $arlima_webservicepage = add_submenu_page('arlima',  __('Web Service', 'arlima'), __('Web Service', 'arlima'), 'edit_posts', 'arlima-webservicepage', 'Arlima_Plugin::loadAdminWebServicePage');

        $this->addAdminPageScriptsAndStylesheets($arlima_mainpage, $arlima_editpage, $arlima_webservicepage);

        if( function_exists('poll_footer_admin' ) ) {
            add_action('admin_footer', 'poll_footer_admin');
        }
    }

    /**
     * @param string $main_page_slug
     * @param string $edit_page_slug
     * @param string $service_page_slug
     */
    function addAdminPageScriptsAndStylesheets($main_page_slug, $edit_page_slug, $service_page_slug) {
        add_action('admin_print_scripts-'.$main_page_slug, array($this, 'addAdminMainPageScripts'));
        add_action('admin_print_styles-'.$main_page_slug, array($this, 'addAdminStyleSheets'));
        add_action('admin_print_styles-'.$main_page_slug,  array($this, 'addTemplateCSS'));
        add_action('admin_print_scripts-'.$main_page_slug, array($this, 'addTinyMCEFilters'));
        add_action('admin_footer-'.$main_page_slug, array($this, 'addTemplateLoadingJS'));

        add_action('admin_print_scripts-'.$edit_page_slug, array($this, 'addAdminEditPageScripts'));
        add_action('admin_print_styles-'.$edit_page_slug, array($this, 'addAdminStyleSheets'));

        add_action('admin_print_styles-'.$service_page_slug, array($this, 'addAdminStyleSheets'));
        add_action('admin_print_scripts-'.$service_page_slug, array($this, 'addAdminServicePageScripts'));

        // Javascript used in meta-box on wp-admin page where blog posts is created
        $php_file = basename($_SERVER['PHP_SELF']);
        if($php_file == 'post-new.php' || $php_file = 'post.php') {
            wp_enqueue_script('arlima_js_admin', ARLIMA_PLUGIN_URL.'/js/admin-post.js', array('jquery' ), self::STATIC_VERSION );
            wp_localize_script('arlima_js_admin', 'ArlimaJSAdmin', array(
                    'ajaxurl' => admin_url('admin-ajax.php' ),
                    'arlimaNonce' => wp_create_nonce('arlima-nonce' ),
                    'imageurl' => ARLIMA_PLUGIN_URL . '/images/',
                    'lang' => array(
                        'notice' => __('Are you sure you want to insert this post in the top of selected article list?', 'arlima'),
                        'wasSentTo' => __('The post is inserted in article list', 'arlima')
                    )
                )
            );
        }
    }

    /**
     * Add javascripts used on list edit page in wp-admin
     */
    function addAdminEditPageScripts() {
        wp_enqueue_script( 'arlima_js', ARLIMA_PLUGIN_URL . 'js/page-edit.js', array( 'jquery' ), self::STATIC_VERSION );
        wp_enqueue_script( 'arlima_js_jquery', ARLIMA_PLUGIN_URL . 'js/arlima/arlima-jquery-plugins.js', array( 'jquery' ), self::STATIC_VERSION );
    }

    /**
     * Add javascripts used on list edit page in wp-admin
     */
    function addAdminServicePageScripts() {
        wp_enqueue_script( 'arlima_js', ARLIMA_PLUGIN_URL . 'js/page-service.js', array( 'jquery' ),  self::STATIC_VERSION );
    }

    /**
     * Adds all javascript files needed in the list editor in wp-admin
     */
    function addAdminMainPageScripts() {

        // Enqueue scissors scripts if installed
        if( Arlima_Plugin::isScissorsInstalled() ) {

            $scissors_url = WP_PLUGIN_URL . '/scissors-continued';
            wp_enqueue_script('scissors_crop', $scissors_url.'/js/jquery.Jcrop.js', array('jquery') );
            wp_enqueue_script('scissors_js', $scissors_url.'/js/scissors.js' );

            $scissors_js_obj = array('ajaxUrl' => admin_url('admin-ajax.php'));
            foreach( array('large', 'medium', 'thumbnail') as $size ) {
                $width = intval(get_option("{$size}_size_w"));
                $height = intval(get_option("{$size}_size_h"));
                $ratio = max(1, $width) / max(1, $height);
                if(!get_option("{$size}_crop"))
                    $ratio = 0;

                $scissors_js_obj[$size.'AspectRatio'] = $ratio;
            }

            echo '<script>var scissors = '.json_encode($scissors_js_obj).';</script>';
        }

        // Add our template css to tinyMCE
        if ( ! function_exists('tdav_css') ) {
            function tdav_css($wp) {
                $wp .= ',' . Arlima_Plugin::getTemplateCSS();
                return $wp;
            }
        }
        add_filter( 'mce_css', 'tdav_css' );


        wp_enqueue_script( 'jquery' );

        wp_register_script(  'jquery-ui', 'http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.16/jquery-ui.js', array( 'jquery' ) );
        wp_enqueue_script( 'jquery-ui' );

        wp_enqueue_script( 'media-upload' );
        wp_enqueue_script( 'thickbox' );

        wp_enqueue_script( 'qtip', ARLIMA_PLUGIN_URL . 'js/jquery/qtip/jquery.qtip.min.js', array( 'jquery' ) );
        wp_enqueue_script( 'colourpicker', ARLIMA_PLUGIN_URL . 'js/jquery/colourpicker/jquery.colourpicker.js', array( 'jquery' ) );

        wp_register_script( 'fancybox',  ARLIMA_PLUGIN_URL . 'js/jquery/fancybox/jquery.fancybox-1.3.4.pack.js', 'jquery', null, true);
        wp_enqueue_script( 'fancybox' );

        wp_enqueue_script( 'jquery-ui-nestedsortable', ARLIMA_PLUGIN_URL . 'js/jquery/jquery.ui.nestedSortable.js', array( 'jquery' ), '1.2' );
        wp_enqueue_script( 'pluploadfull', ARLIMA_PLUGIN_URL . 'js/misc/plupload.full.js', array( 'jquery' ));
        wp_enqueue_script( 'jquery-tmpl', ARLIMA_PLUGIN_URL . 'js/jquery/jquery.tmpl.min.js', array( 'jquery' ) );
        wp_enqueue_script( 'arlima-jquery-plugins', ARLIMA_PLUGIN_URL . 'js/arlima/arlima-jquery-plugins.js', array( 'jquery' ),self::STATIC_VERSION );
        wp_enqueue_script( 'arlima-template-loader', ARLIMA_PLUGIN_URL . 'js/arlima/template-loader.js', array( 'jquery' ), self::STATIC_VERSION );
        wp_enqueue_script( 'arlima-js', ARLIMA_PLUGIN_URL . 'js/arlima/arlima.js', array( 'jquery' ),  self::STATIC_VERSION );
        wp_enqueue_script( 'arlima-plupload-init', ARLIMA_PLUGIN_URL . 'js/arlima/plupload-init.js', array( 'jquery' ), self::STATIC_VERSION );
        wp_enqueue_script( 'arlima-main-js', ARLIMA_PLUGIN_URL . 'js/page-main.js', array( 'jquery' ), self::STATIC_VERSION );

        // Use the newest version of hotkeys (wordpress uses old beta)
        wp_deregister_script('jquery-hotkeys');
        wp_register_script('jquery-hotkeys-new-version', ARLIMA_PLUGIN_URL . 'js/jquery/jquery.hotkeys.js', array(), self::STATIC_VERSION );
        wp_enqueue_script('jquery-hotkeys-new-version');

        wp_localize_script( 'arlima-js', 'ArlimaJS', array(
                'ajaxurl' => admin_url( 'admin-ajax.php' ),
                'arlimaNonce' => wp_create_nonce( 'arlima-nonce' ),
                'imageurl' => ARLIMA_PLUGIN_URL . '/images/',
                'baseurl' => get_bloginfo('url'),
                'is_admin' => current_user_can('manage_options') ? 1:0,
                'preview_query_arg' =>  Arlima_List::QUERY_ARG_PREVIEW,
                'lang' => array( // todo: but these args in a separate .js.php file when this array gets to long
                    'unsaved' => __('You have one, or more, unsaved article lists', 'arlima'),
                    'laterVersion' => __('It exists an older version of this article list', 'arlima'),
                    'overWrite' => __('Do you still want to save this version of the list?', 'arlima'),
                    'severalExtras' => __('This article list has more than one extra-streamer', 'arlima'),
                    'changesBeforeRemove' => __('You have made changes to this list, do you want to remove it anyway?', 'arlima'),
                    'wantToRemove' => __('Do you want to remove "', 'arlima'),
                    'fromList' => __('" from this article list?', 'arlima'),
                    'chooseImage' => __('Choose image', 'arlima'),
                    'admin_lock' => __('This article is locked by admin', 'arlima'),
                    'admin_only' => __('Only administrators can manage article locks', 'arlima'),
                    'noList' => __('No list is active!', 'arlima'),
                    'noImages' => __('This article has no related image', 'arlima'),
                    'noConnection' => __('this article is not connected to any post', 'arlima'),
                    'listRemoved' => __('This list have been removed!', 'arlima'),
                    'savePreview' => __('to save article list', 'arlima'),
                    'isSaved' => __('This list has no unsaved changes', 'arlima'),
                    'missingPreviewPage' => __('This list is missing a preview page', 'arlima'),
                    'hasUnsavedChanges' => __('This list has unsaved changes', 'arlima'),
                    'dragAndDrop' => __('Drag images to this container', 'arlima'),
                    'sticky' => __('Sticky', 'arlima'),
                    'loggedOut' => __('Your login session seems to have expired, pls reload the page!', 'arlima')
                )
            )
        );
    }

    /**
     * Will enqueue the css for the presentation of articles in an arlima list
     */
    function addTemplateCSS() {
        wp_enqueue_style('arlima_template_css', self::getTemplateCSS(), array(), '1.0');
    }

    /**
     * Get the path to the CSS file that controls the presentation of article in
     * an arlima list
     * @static
     * @return string
     */
    public static function getTemplateCSS() {
        return apply_filters('arlima_template_css',   ARLIMA_PLUGIN_URL . 'css/template.css');
    }

    /**
     * Will output javascript that loads all jQuery templates from backend
     */
    function addTemplateLoadingJS() {
        $tmpl_resolver = new Arlima_TemplatePathResolver();
        $templates = array();
        foreach($tmpl_resolver->getTemplateFiles() as $directory => $tmpl_files) {
            foreach($tmpl_files as $file) {
                $templates[] = $tmpl_resolver->fileToUrl($file);
            }
        }

        ?>
        <script>
            var tmpls = [];
            <?php foreach($templates as $tmpl): ?>
                tmpls.push('<?php echo $tmpl ?>?v=4');
            <?php endforeach; ?>
            ArlimaTemplateLoader.load(tmpls);
            <?php if( !empty($_GET['open_list']) ): ?>
                var loadArlimListOnLoad = <?php echo intval($_GET['open_list']); ?>;
            <?php endif; ?>
        </script>
        <?php
    }

    /**
     * Add all stylesheets needed by this plugin in wp-admin
     */
    function addAdminStyleSheets() {
        wp_enqueue_style('arlima_css', ARLIMA_PLUGIN_URL . 'css/admin.css', null, self::STATIC_VERSION );
        wp_enqueue_style('thickbox' );
        wp_enqueue_style('jquery_ui_css', 'http://ajax.googleapis.com/ajax/libs/jqueryui/1.8/themes/smoothness/jquery-ui.css' );
        wp_enqueue_style('qtip_css', ARLIMA_PLUGIN_URL . 'js/jquery/qtip/jquery.qtip.css' );
        wp_enqueue_style('colourpicker_css', ARLIMA_PLUGIN_URL . 'js/jquery/colourpicker/colourpicker.css' );
        wp_enqueue_style('fancy_css', ARLIMA_PLUGIN_URL . 'js/jquery/fancybox/jquery.fancybox-1.3.4.css' );
    }

    /**
     * Will hook into tinyMCE setup and modify the functionality of tinyMCE HTML editor
     * @TODO: Decide whether or not this should be moved from this plugin to somewhere else
     */
    function addTinyMCEFilters() {

        add_filter('mce_external_plugins', function( $plugin_array ) {
            $plugin_array['vkentrywords'] = ARLIMA_PLUGIN_URL . 'js/tinymce/plugins/vkentrywords/editor_plugin.js';
            return $plugin_array;
        });

        add_filter('mce_buttons', function( $buttons ) {
                unset( $buttons[ array_search('wp_more', $buttons ) ] );
                unset( $buttons[ array_search('fullscreen', $buttons ) ] );
                unset( $buttons[ array_search('vkpreamble', $buttons ) ] );
                unset( $buttons[ array_search('vksubheading', $buttons ) ] );
                array_unshift($buttons, "vkentrywords");
                return $buttons;
            }
            , 20);

        add_filter('mce_buttons_2', function( $buttons ) {
            unset( $buttons[ array_search('outdent', $buttons ) ] );
            unset( $buttons[ array_search('indent', $buttons ) ] );
            unset( $buttons[ array_search('wp_help', $buttons ) ] );
            return $buttons;
        }, 20);
    }

    /**
     * Tells whether or not the plugin ScissorsContinued is installed
     * @static
     * @return bool
     */
    public static function isScissorsInstalled() {
        return self::$is_scissors_installed;
    }

    /**
     * Tells whether or not plugin WP Related Posts is installed
     * @static
     * @return bool|null
     */
    public static function isWPRelatedPostsInstalled() {
        return self::$is_wp_related_post_installed;
    }

    /**
     * Class loader that either tries to load the class from arlima class
     * directory or jQueryTmpl directory
     * @static
     * @param string $class
     */
    public static function classLoader($class) {
        // use substr instead of strpos or regexp, way faster in this case
        if( substr($class, 0, 7) == 'Arlima_' ) {
            require_once ARLIMA_PLUGIN_PATH.'/classes/'.substr($class, 7).'.php';
        }
        elseif( substr($class, 0, 10) == 'jQueryTmpl' ) {
            $jquery_tmpl_class = ARLIMA_PLUGIN_PATH.'/classes/jquery-tmpl-php/'.str_replace('_', DIRECTORY_SEPARATOR, $class).'.php';
            require_once $jquery_tmpl_class;
        }

        // Deprecated classes
        elseif( substr($class, 0, 6) == 'Arlima') {
            require_once ARLIMA_PLUGIN_PATH.'/classes/deprecated.php';
        }
    }

    /**
     * @static
     * @param string $func
     * @param float $since
     * @param string|bool $replacement - optional
     */
    public static function warnAboutUseOfDeprecatedFunction($func, $since, $replacement=false) {
        if(WP_DEBUG) {
            trigger_error( sprintf('Use of deprecated arlima function %s, deprecated since vesion %f %s', $func, (string)$since, $replacement ? ' use '.$replacement.' instead':''), E_USER_WARNING );
        }
    }

    /**
     * @static
     * @param string $page
     */
    protected static function loadAdminPage($page) {
        ?>
        <div class="wrap"><div id="icon-plugins" class="icon32"></div>
            <h2><?php _e('Article List Manager', 'arlima') ?></h2>
            <?php require ARLIMA_PLUGIN_PATH . '/pages/'.$page.'.php'; ?>
        </div>
        <?php
    }

    public static function loadAdminMainPage() {
        self::loadAdminPage('main');
    }

    public static function loadAdminEditPage() {
        self::loadAdminPage('edit');
    }

    public static function loadAdminHelpPage() {
        self::loadAdminPage('help');
    }

    public static function loadAdminWebServicePage() {
        self::loadAdminPage('service');
    }

    /**
     * Will output a set of option elements containing streamer background colors.
     * @static
     */
    public static function loadStreamerColos() {
        // Make it possible for theme or other plugins to
        // define their own streamer colors
        $predefined_colors = apply_filters('arlima_streamer_colors', array());
        if(!empty($predefined_colors)) {
            foreach($predefined_colors as $hex) {
                echo '<option value="'.$hex.'">#'.$hex.'</option>';
            }
        }

        // default colors
        else {
            $cs = array( '00', '33', '66', '99', 'CC', 'FF' );
            for( $i=0; $i<6; $i++ ) {
                for( $j=0; $j<6; $j++ ) {
                    for( $k=0; $k<6; $k++ ) {
                        $c = $cs[ $i ] .$cs[ $j ] .$cs[ $k ];
                        echo '<option value="' . $c . '">#' . $c . '</option>\n';
                    }
                }
            }
        }
    }

    /**
     * If current theme is missing an arlima page template this function will
     * output a div with information about the issue
     * @static
     */
    public static function warnAboutMissingTemplate() {
        $arlima_template_path = get_stylesheet_directory().'/page-arlima.php';
        if( !file_exists($arlima_template_path) ): ?>
            <div id="message" class="updated">
                <p>
                    Theme file &quot;page-arlima.php&quot; is missing. Please copy file
                    <strong><?php echo str_replace(ABSPATH, '', WP_PLUGIN_DIR . '/arlima/page-arlima-example.php') ?></strong>
                    to <strong><?php echo str_replace(ABSPATH, '', $arlima_template_path) ?></strong> and reload this page.
                </p>
                <p>
                    <em>If you just installed this plugin for the first time you also need to do the following:</em>
                </p>
                <ol>
                    <li>Go to &quot;Pages&quot; -&gt; &quot;All pages&quot; in wp-admin and open the page named &quot;Home&quot;</li>
                    <li>Change page template to &quot;Article List Page&quot;</li>
                    <li>Add a custom field with name &quot;arlima&quot; and value &quot;frontpage&quot;</li>
                </ol>
            </div>
        <?php endif;
    }
}