<?php
/**
 * @package     Joomla.Administrator
 * @subpackage  com_admin
 *
 * @copyright   Copyright (C) 2005 - 2018 Open Source Matters, Inc. All rights reserved.
 * @license     GNU General Public License version 2 or later; see LICENSE.txt
 */

defined('_JEXEC') or die;

use Joomla\String\StringHelper;

/**
 * Admin Component Help Model
 *
 * @since  1.6
 */
class AdminModelHelp extends JModelLegacy
{
	/**
	 * The search string
	 *
	 * @var    string
	 * @since  1.6
	 */
	protected $help_search = null;

	/**
	 * The page to be viewed
	 *
	 * @var    string
	 * @since  1.6
	 */
	protected $page = null;

	/**
	 * The ISO language tag
	 *
	 * @var    string
	 * @since  1.6
	 */
	protected $lang_tag = null;

	/**
	 * Table of contents
	 *
	 * @var    array
	 * @since  1.6
	 */
	protected $toc = null;

	/**
	 * URL for the latest version check
	 *
	 * @var    string
	 * @since  1.6
	 */
	protected $latest_version_check = null;

	/**
	 * Method to get the help search string
	 *
	 * @return  string  Help search string
	 *
	 * @since   1.6
	 */
	public function &getHelpSearch()
	{
		if (is_null($this->help_search))
		{
			$this->help_search = JFactory::getApplication()->input->getString('helpsearch');
		}

		return $this->help_search;
	}

	/**
	 * Method to get the page
	 *
	 * @return  string  The page
	 *
	 * @since   1.6
	 */
	public function &getPage()
	{
		if (is_null($this->page))
		{
			$this->page = JHelp::createUrl(JFactory::getApplication()->input->get('page', 'JHELP_START_HERE'));
		}

		return $this->page;
	}

	/**
	 * Method to get the lang tag
	 *
	 * @return  string  lang iso tag
	 *
	 * @since  1.6
	 */
	public function getLangTag()
	{
		if (is_null($this->lang_tag))
		{
			$this->lang_tag = JFactory::getLanguage()->getTag();

			if (!is_dir(JPATH_BASE . '/help/' . $this->lang_tag))
			{
				// Use English as fallback
				$this->lang_tag = 'en-GB';
			}
		}

		return $this->lang_tag;
	}

	/**
	 * Method to get the table of contents
	 *
	 * @return  array  Table of contents
	 */
	public function &getToc()
	{
		if (!is_null($this->toc))
		{
			return $this->toc;
		}

		// Get vars
		$lang_tag    = $this->getLangTag();
		$help_search = $this->getHelpSearch();

		// New style - Check for a TOC JSON file
		if (file_exists(JPATH_BASE . '/help/' . $lang_tag . '/toc.json'))
		{
			$data = json_decode(file_get_contents(JPATH_BASE . '/help/' . $lang_tag . '/toc.json'));

			// Loop through the data array
			foreach ($data as $key => $value)
			{
				$this->toc[$key] = JText::_('COM_ADMIN_HELP_' . $value);
			}

			// Sort the Table of Contents
			asort($this->toc);

			return $this->toc;
		}

		// Get Help files
		jimport('joomla.filesystem.folder');
		$files = JFolder::files(JPATH_BASE . '/help/' . $lang_tag, '\.xml$|\.html$');
		$this->toc = array();

		foreach ($files as $file)
		{
			$buffer = file_get_contents(JPATH_BASE . '/help/' . $lang_tag . '/' . $file);

			if (!preg_match('#<title>(.*?)</title>#', $buffer, $m))
			{
				continue;
			}

			$title = trim($m[1]);

			if (!$title)
			{
				continue;
			}

			// Translate the page title
			$title = JText::_($title);

			// Strip the extension
			$file = preg_replace('#\.xml$|\.html$#', '', $file);

			if ($help_search && StringHelper::strpos(StringHelper::strtolower(strip_tags($buffer)), StringHelper::strtolower($help_search)) === false)
			{
				continue;
			}

			// Add an item in the Table of Contents
			$this->toc[$file] = $title;
		}

		// Sort the Table of Contents
		asort($this->toc);

		return $this->toc;
	}

	/**
	 * Method to get the latest version check
	 *
	 * @return  string  Latest Version Check URL
	 */
	public function &getLatestVersionCheck()
	{
		if (!$this->latest_version_check)
		{
			$override = 'https://help.joomla.org/proxy/index.php?keyref=Help{major}{minor}:'
				. 'Joomla_Version_{major}_{minor}_{maintenance}/{langcode}&amp;lang={langcode}';
			$this->latest_version_check = JHelp::createUrl('JVERSION', false, $override);
		}

		return $this->latest_version_check;
	}
}