toc.php

<?php
/**
 * Toc v1.3.1
 *
 * This plugin automagically generates a (minified) Table of Contents
 * based on special markers in the document and adds it into the
 * resulting HTML document.
 *
 * Dual licensed under the MIT or GPL Version 3 licenses, see LICENSE.
 * http://benjamin-regler.de/license/
 *
 * @package     Toc
 * @version     1.3.1
 * @link        <https://github.com/sommerregen/grav-plugin-external-links>
 * @author      Benjamin Regler <sommerregen@benjamin-regler.de>
 * @copyright   2015, Benjamin Regler
 * @license     <http://opensource.org/licenses/MIT>        MIT
 * @license     <http://opensource.org/licenses/GPL-3.0>    GPLv3
 */

namespace Grav\Plugin;

use Grav\Common\Plugin;
use Grav\Common\Data\Data;
use Grav\Common\Page\Page;
use Grav\Plugin\Shortcodes;
use RocketTheme\Toolbox\Event\Event;

/**
 * Toc
 *
 * This plugin automagically generates a (minified) Table of Contents
 * based on special markers in the document and adds it into the
 * resulting HTML document.
 */
class TocPlugin extends Plugin
{
  /** ---------------------------
   * Private/protected properties
   * ----------------------------
   */

  /**
   * Instance of Toc class
   *
   * @var object
   */
  protected $toc;

  /** -------------
   * Public methods
   * --------------
   */

  /**
   * Return a list of subscribed events.
   *
   * @return array    The list of events of the plugin of the form
   *                      'name' => ['method_name', priority].
   */
  public static function getSubscribedEvents()
  {
    return [
      'onPluginsInitialized' => ['onPluginsInitialized', 0],
    ];
  }

  /**
   * Initialize configuration
   */
  public function onPluginsInitialized()
  {
    if ($this->isAdmin()) {
      $this->active = false;
      return;
    }

    if ($this->config->get('plugins.toc.enabled')) {
      $this->enable([
        // Page
        'onPageContentProcessed' => ['onPageContentProcessed', 0],

        // Twig
        'onTwigInitialized' => ['onTwigInitialized', 0],
        'onTwigSiteVariables' => ['onTwigSiteVariables', 0],
        'onTwigTemplatePaths' => ['onTwigTemplatePaths', 0],

        // Shortcodes
        'onShortcodesInitialized' => ['onShortcodesInitialized', 0]
      ]);
    }
  }

  /**
   * Apply TOC filter to content, when each page has not been
   * cached yet.
   *
   * @param  Event  $event The event when 'onPageContentProcessed' was
   *                       fired.
   */
  public function onPageContentProcessed(Event $event)
  {
    /** @var Page $page */
    $page = $event['page'];

    $config = $this->mergeConfig($page);
    if ($config->get('enabled') && $config->get('process')) {
      // Get content, apply TocFilter and save modified page content
      $content = $page->getRawContent();
      $page->setRawContent(
        $this->tocFilter($content, $config->toArray(), $page)
      );
    }
  }

  /**
   * Initialize Twig configuration and filters.
   */
  public function onTwigInitialized()
  {
    // Expose tocFilter
    $this->grav['twig']->twig()->addFilter(
      new \Twig_SimpleFilter('toc', [$this, 'tocFilter'], ['is_safe' => ['html']])
    );
  }

  /**
   * Add current directory to Twig lookup paths.
   */
  public function onTwigTemplatePaths()
  {
    $this->grav['twig']->twig_paths[] = __DIR__ . '/templates';
  }

  /**
   * Set needed variables to display a table of contents.
   */
  public function onTwigSiteVariables() {
    if ($this->config->get('plugins.toc.built_in_css')) {
      $this->grav['assets']->add('plugin://toc/assets/css/toc.css');
    }
  }

  /**
   * Filter to automatically create a (minified) table of contents.
   *
   * @param  string $content The content to be filtered
   * @param  array  $options Array of options for the TOC filter
   *
   * @return string          The content with inserted anchor- and
   *                         permalinks in headings and table of contents
   *                         blocks
   */
  public function tocFilter($content, $params = [])
  {
    // Get custom user configuration
    $page = func_num_args() > 2 ? func_get_arg(2) : $this->grav['page'];
    $config = $this->mergeConfig($page, true, $params);

    // Render Toc
    return $this->init()->render($content, $config, $page);
  }

  /**
   * Register {{% toc %}}, {{% minitoc %}} and {{% tocify %}} shortcodes.
   *
   * @param  Event  $event An event object.
   */
  public function onShortcodesInitialized(Event $event)
  {
    $toc = $this->init();
    $function = function($event) {
      // Update header to bypass evaluation
      if (isset($event['page']->header()->toc->enabled)) {
        $event['page']->header()->toc->enabled = true;
      }

      return '['.strtoupper($event['tag']).']';
    };

    $shortcodes = [
      new Shortcodes\InlineShortcode('toc', $function),
      new Shortcodes\InlineShortcode('minitoc', $function),
      // new Shortcodes\BlockShortcode('tocify', [$toc, 'tocifyShortcode'])
    ];

    // Register {{% toc %}}, {{% minitoc %}} and {{% tocify %}} shortcode
    $event['shortcodes']->register($shortcodes);
  }

  /** -------------------------------
   * Private/protected helper methods
   * --------------------------------
   */

  /**
   * Initialize plugin and all dependencies.
   *
   * @return \Grav\Plugin\ExternalLinks   Returns ExternalLinks instance.
   */
  protected function init()
  {
    if (!$this->toc) {
      // Initialize Toc class
      require_once(__DIR__ . '/classes/Toc.php');
      $this->toc = new Toc();
    }

    return $this->toc;
  }
}