<?php /** @file */

namespace Zotlabs\Render;

use App;

require_once('include/security.php');
require_once('include/menu.php');

/**
 * @brief Comanche Page Description Language.
 *
 * Comanche is a markup language similar to bbcode with which to create elaborate
 * and complex web pages by assembling them from a series of components - some of
 * which are pre-built and others which can be defined on the fly. Comanche uses
 * a Page Decription Language to create these pages.
 *
 * Comanche primarily chooses what content will appear in various regions of the
 * page. The various regions have names and these names can change depending on
 * what layout template you choose.
 */

class Comanche {

	function parse($s, $pass = 0) {
		$matches = [];

		$cnt = preg_match_all("/\[comment\](.*?)\[\/comment\]/ism", $s, $matches, PREG_SET_ORDER);
		if ($cnt) {
			foreach ($matches as $mtch) {
				$s = str_replace($mtch[0], '', $s);
			}
		}

		/*
		 * This section supports the "switch" statement of the form given by the following
		 * example. The [default][/default] block must be the last in the arbitrary
		 * list of cases. The first case that matches the switch variable is used
		 * and the rest are not evaluated.
		 *
		 * [switch observer.language]
		 * [case de]
		 *   [block]german-content[/block]
		 * [/case]
		 * [case es]
		 *   [block]spanish-content[/block]
		 * [/case]
		 * [default]
		 *   [block]english-content[/block]
		 * [/default]
		 * [/switch]
		 */

		$cnt = preg_match_all("/\[switch (.*?)\](.*?)\[default\](.*?)\[\/default\]\s*\[\/switch\]/ism", $s, $matches, PREG_SET_ORDER);
		if ($cnt) {
			foreach ($matches as $mtch) {
				$switch_done = 0;
				$switch_var = $this->get_condition_var($mtch[1]);
				$default = $mtch[3];
				$cases = [];
				$cntt = preg_match_all("/\[case (.*?)\](.*?)\[\/case\]/ism", $mtch[2], $cases, PREG_SET_ORDER);
				if ($cntt) {
					foreach ($cases as $case) {
						if ($case[1] === $switch_var) {
							$switch_done = 1;
							$s = str_replace($mtch[0], $case[2], $s);
							break;
						}
					}
					if ($switch_done === 0) {
						$s = str_replace($mtch[0], $default, $s);
					}
				}
			}
		}

		$cnt = preg_match_all("/\[if (.*?)\](.*?)\[else\](.*?)\[\/if\]/ism", $s, $matches, PREG_SET_ORDER);
		if ($cnt) {
			foreach ($matches as $mtch) {
				if ($this->test_condition($mtch[1])) {
					$s = str_replace($mtch[0], $mtch[2], $s);
				}
				else {
					$s = str_replace($mtch[0], $mtch[3], $s);
				}
			}
		}
		else {
			$cnt = preg_match_all("/\[if (.*?)\](.*?)\[\/if\]/ism", $s, $matches, PREG_SET_ORDER);
			if ($cnt) {
				foreach ($matches as $mtch) {
					if ($this->test_condition($mtch[1])) {
						$s = str_replace($mtch[0], $mtch[2], $s);
					}
					else {
						$s = str_replace($mtch[0], '', $s);
					}
				}
			}
		}
		if ($pass == 0) {
			$this->parse_pass0($s);
		}
		else {
			$this->parse_pass1($s);
		}
	}

	function parse_pass0($s) {

		$matches = null;

		$cnt = preg_match("/\[layout\](.*?)\[\/layout\]/ism", $s, $matches);
		if ($cnt) {
			App::$page['template'] = trim($matches[1]);
		}
		
		$cnt = preg_match("/\[template=(.*?)\](.*?)\[\/template\]/ism", $s, $matches);
		if ($cnt) {
			App::$page['template'] = trim($matches[2]);
			App::$page['template_style'] = trim($matches[2]) . '_' . $matches[1];
		}

		$cnt = preg_match("/\[template\](.*?)\[\/template\]/ism", $s, $matches);
		if ($cnt) {
			App::$page['template'] = trim($matches[1]);
		}

		$cnt = preg_match("/\[theme=(.*?)\](.*?)\[\/theme\]/ism", $s, $matches);
		if ($cnt) {
			App::$layout['schema'] = trim($matches[1]);
			App::$layout['theme'] = trim($matches[2]);
		}

		$cnt = preg_match("/\[theme\](.*?)\[\/theme\]/ism", $s, $matches);
		if ($cnt) {
			App::$layout['theme'] = trim($matches[1]);
		}
		
		$cnt = preg_match("/\[navbar\](.*?)\[\/navbar\]/ism", $s, $matches);
		if ($cnt) {
			App::$layout['navbar'] = trim($matches[1]);
		}

		$cnt = preg_match_all("/\[webpage\](.*?)\[\/webpage\]/ism", $s, $matches, PREG_SET_ORDER);
		if ($cnt) {
			// only the last webpage definition is used if there is more than one
			foreach ($matches as $mtch) {
				App::$layout['webpage'] = $this->webpage($a,$mtch[1]);
			}
		}
	}

	function parse_pass1($s) {
		$cnt = preg_match_all("/\[region=(.*?)\](.*?)\[\/region\]/ism", $s, $matches, PREG_SET_ORDER);
		if ($cnt) {
			foreach ($matches as $mtch) {
				App::$layout['region_' . $mtch[1]] = $this->region($mtch[2],$mtch[1]);
			}
		}
	}

	/**
	 * @brief Replace conditional variables with real values.
	 *
	 * Currently supported condition variables:
	 *   * $config.xxx.yyy - get_config with cat = xxx and k = yyy
	 *   * $request - request uri for this page
	 *   * $observer.language - viewer's preferred language (closest match)
	 *   * $observer.address - xchan_addr or false
	 *   * $observer.name - xchan_name or false
	 *   * $observer - xchan_hash of observer or empty string
	 *   * $local_channel - logged in channel_id or false
	 *
	 * @param string $v The conditional variable name
	 * @return string|boolean
	 */
	function get_condition_var($v) {
		if ($v) {
			$x = explode('.', $v);
			if ($x[0] == 'config') {
				return get_config($x[1],$x[2]);
			}
			elseif ($x[0] === 'request') {
				return $_SERVER['REQUEST_URI'];
			}
			elseif ($x[0] === 'local_channel') {
				return local_channel();
			}
			elseif ($x[0] === 'observer') {
				if (count($x) > 1) {
					if ($x[1] == 'language') {
						return App::$language;
					}
					$y = App::get_observer();
					if (! $y) {
						return false;
					}
					if ($x[1] == 'address') {
						return $y['xchan_addr'];
					}
					elseif ($x[1] == 'name') {
						return $y['xchan_name'];
					}
					elseif ($x[1] == 'webname') {
						return substr($y['xchan_addr'],0,strpos($y['xchan_addr'],'@'));
					}
					return false;
				}
				return get_observer_hash();
			}
			else {
				return false;
			}
		}
		return false;
	}

	/**
	 * @brief Test for Conditional Execution conditions.
	 *
	 * This is extensible. The first version of variable testing supports tests of the forms:
	 *
	 * - [if $config.system.foo ~= baz] which will check if get_config('system','foo') contains the string 'baz';
	 * - [if $config.system.foo == baz] which will check if get_config('system','foo') is the string 'baz';
	 * - [if $config.system.foo != baz] which will check if get_config('system','foo') is not the string 'baz';
	 * - [if $config.system.foo >= 3] which will check if get_config('system','foo') is greater than or equal to 3;
	 * - [if $config.system.foo > 3] which will check if get_config('system','foo') is greater than 3;
	 * - [if $config.system.foo <= 3] which will check if get_config('system','foo') is less than or equal to 3;
	 * - [if $config.system.foo < 3] which will check if get_config('system','foo') is less than 3;
	 *
	 * - [if $config.system.foo {} baz] which will check if 'baz' is an array element in get_config('system','foo')
	 * - [if $config.system.foo {*} baz] which will check if 'baz' is an array key in get_config('system','foo')
	 * - [if $config.system.foo] which will check for a return of a true condition for get_config('system','foo');
	 *
	 * The values 0, '', an empty array, and an unset value will all evaluate to false.
	 *
	 * @param int|string $s
	 * @return boolean
	 */
	function test_condition($s) {

		if (preg_match('/[\$](.*?)\s\~\=\s(.*?)$/',$s,$matches)) {
			$x = $this->get_condition_var($matches[1]);
			if (stripos($x,trim($matches[2])) !== false) {
				return true;
			}
			return false;
		}

		if (preg_match('/[\$](.*?)\s\=\=\s(.*?)$/',$s,$matches)) {
			$x = $this->get_condition_var($matches[1]);
			if ($x == trim($matches[2])) {
				return true;
			}
			return false;
		}

		if (preg_match('/[\$](.*?)\s\!\=\s(.*?)$/',$s,$matches)) {
			$x = $this->get_condition_var($matches[1]);
			if ($x != trim($matches[2])) {
				return true;
			}
			return false;
		}

		if (preg_match('/[\$](.*?)\s\>\=\s(.*?)$/',$s,$matches)) {
			$x = $this->get_condition_var($matches[1]);
			if ($x >= trim($matches[2])) {
				return true;
			}
			return false;
		}

		if (preg_match('/[\$](.*?)\s\<\=\s(.*?)$/',$s,$matches)) {
			$x = $this->get_condition_var($matches[1]);
			if ($x <= trim($matches[2])) {
				return true;
			}
			return false;
		}

		if (preg_match('/[\$](.*?)\s\>\s(.*?)$/',$s,$matches)) {
			$x = $this->get_condition_var($matches[1]);
			if ($x > trim($matches[2])) {
				return true;
			}
			return false;
		}

		if (preg_match('/[\$](.*?)\s\>\s(.*?)$/',$s,$matches)) {
			$x = $this->get_condition_var($matches[1]);
			if ($x < trim($matches[2])) {
				return true;
			}
			return false;
		}

		if (preg_match('/[\$](.*?)\s\{\}\s(.*?)$/',$s,$matches)) {
			$x = $this->get_condition_var($matches[1]);
			if (is_array($x) && in_array(trim($matches[2]),$x)) {
				return true;
			}
			return false;
		}

		if (preg_match('/[\$](.*?)\s\{\*\}\s(.*?)$/',$s,$matches)) {
			$x = $this->get_condition_var($matches[1]);
			if (is_array($x) && array_key_exists(trim($matches[2]),$x)) {
				return true;
			}
			return false;
		}

		if (preg_match('/[\$](.*?)$/',$s,$matches)) {
			$x = $this->get_condition_var($matches[1]);
			if ($x) {
				return true;
			}
			return false;
		}
		return false;
	}

	/**
	 * @brief Return rendered menu for current channel_id.
	 *
	 * @see menu_render()
	 * @param string $s
	 * @param string $class (optional) default empty
	 * @return string
	 */
	function menu($s, $class = '') {

		$channel_id = $this->get_channel_id();
		$name = $s;

		$cnt = preg_match_all("/\[var=(.*?)\](.*?)\[\/var\]/ism", $s, $matches, PREG_SET_ORDER);
		if ($cnt) {
			foreach ($matches as $mtch) {
				$var[$mtch[1]] = $mtch[2];
				$name = str_replace($mtch[0], '', $name);
			}
		}

		if ($channel_id) {
			$m = menu_fetch($name, $channel_id, get_observer_hash());
			return menu_render($m, $class, $edit = false, $var);
		}
	}


	function replace_region($match) {
		if (array_key_exists($match[1], App::$page)) {
			return App::$page[$match[1]];
		}
	}

	/**
	 * @brief Returns the channel_id of the profile owner of the page.
	 *
	 * Returns the channel_id of the profile owner of the page, or the local_channel
	 * if there is no profile owner. Otherwise returns 0.
	 *
	 * @return int channel_id
	 */
	function get_channel_id() {
		$channel_id = ((is_array(App::$profile)) ? App::$profile['profile_uid'] : 0);

		if ((! $channel_id) && (local_channel())) {
			$channel_id = local_channel();
		}
		return $channel_id;
	}

	/**
	 * @brief Returns a parsed block.
	 *
	 * @param string $s
	 * @param string $class (optional) default empty
	 * @return string parsed HTML of block
	 */
	function block($s, $class = '') {
		$var = [];
		$matches = [];
		$name = $s;
		$class = (($class) ? $class : 'bblock widget');

		$cnt = preg_match_all("/\[var=(.*?)\](.*?)\[\/var\]/ism", $s, $matches, PREG_SET_ORDER);
		if ($cnt) {
			foreach ($matches as $mtch) {
				$var[$mtch[1]] = $mtch[2];
				$name = str_replace($mtch[0], '', $name);
			}
		}

		$o = '';
		$channel_id = $this->get_channel_id();

		if ($channel_id) {
			$r = q("select * from item inner join iconfig on iconfig.iid = item.id and item.uid = %d
				and iconfig.cat = 'system' and iconfig.k = 'BUILDBLOCK' and iconfig.v = '%s' limit 1",
				intval($channel_id),
				dbesc($name)
			);

			if ($r) {
				//check for eventual menus in the block and parse them
				$cnt = preg_match_all("/\[menu\](.*?)\[\/menu\]/ism", $r[0]['body'], $matches, PREG_SET_ORDER);
				if ($cnt) {
					foreach ($matches as $mtch) {
						$r[0]['body'] = str_replace($mtch[0], $this->menu(trim($mtch[1])), $r[0]['body']);
					}
				}
				$cnt = preg_match_all("/\[menu=(.*?)\](.*?)\[\/menu\]/ism", $r[0]['body'], $matches, PREG_SET_ORDER);
				if ($cnt) {
					foreach ($matches as $mtch) {
						$r[0]['body'] = str_replace($mtch[0],$this->menu(trim($mtch[2]),$mtch[1]),$r[0]['body']);
					}
				}

				// emit the block
				$o .= (($var['wrap'] == 'none') ? '' : '<div class="' . $class . '">');

				if ($r[0]['title'] && trim($r[0]['body']) != '$content') {
					$o .= '<h3>' . $r[0]['title'] . '</h3>';
				}

				if (trim($r[0]['body']) === '$content') {
					$o .= App::$page['content'];
				}
				else {
					$o .= prepare_text($r[0]['body'], $r[0]['mimetype']);
				}

				$o .= (($var['wrap'] == 'none') ? '' : '</div>');
			}
		}

		return $o;
	}

	/**
	 * @brief Include JS depending on framework.
	 *
	 * @param string $s
	 * @return string
	 */
	function js($s) {

		switch ($s) {
			case 'jquery':
				$path = 'view/js/jquery.js';
				break;
			case 'bootstrap':
				$path = 'vendor/twbs/bootstrap/dist/js/bootstrap.bundle.min.js';
				break;
			case 'foundation':
				$path = 'library/foundation/js/foundation.js';
				$init = "\r\n" . '<script>$(document).ready(function() { $(document).foundation(); });</script>';
				break;
		}

		$ret = '<script src="' . z_root() . '/' . $path . '" ></script>';
		if ($init) {
			$ret .= $init;
		}
		return $ret;
	}

	/**
	 * @brief Include CSS depending on framework.
	 *
	 * @param string $s
	 * @return string
	 */
	function css($s) {

		switch ($s) {
			case 'bootstrap':
				$path = 'vendor/twbs/bootstrap/dist/css/bootstrap.min.css';
				break;
			case 'foundation':
				$path = 'library/foundation/css/foundation.min.css';
				break;
		}

		$ret = '<link rel="stylesheet" href="' . z_root() . '/' . $path . '" type="text/css" media="screen">';

		return $ret;
	}

	/**
	 * This doesn't really belong in Comanche, but it could also be argued that it is the perfect place.
	 * We need to be able to select what kind of template and decoration to use for the webpage at the heart of our content.
	 * For now we'll allow an '[authored]' element which defaults to name and date, or 'none' to remove these, and perhaps
	 * 'full' to provide a social network style profile photo.
	 *
	 * But leave it open to have richer templating options and perhaps ultimately discard this one, once we have a better idea
	 * of what template and webpage options we might desire.
	 *
	 * @param[in,out] array $a
	 * @param string $s
	 * @return array
	 */
	function webpage(&$a, $s) {
		$ret = [];
		$matches = [];

		$cnt = preg_match_all("/\[authored\](.*?)\[\/authored\]/ism", $s, $matches, PREG_SET_ORDER);
		if ($cnt) {
			foreach ($matches as $mtch) {
				$ret['authored'] = $mtch[1];
			}
		}

		return $ret;
	}

	/**
	 * @brief Render a widget.
	 *
	 * @param string $name
	 * @param string $text
	 */
	function widget($name, $text) {
		$vars = [];
		$matches = [];

		$cnt = preg_match_all("/\[var=(.*?)\](.*?)\[\/var\]/ism", $text, $matches, PREG_SET_ORDER);
		if ($cnt) {
			foreach ($matches as $mtch) {
				$vars[$mtch[1]] = $mtch[2];
			}
		}

		if (! purify_filename($name)) {
			return '';
		}

		$clsname = ucfirst($name);
		$nsname = "\\Zotlabs\\Widget\\" . $clsname;

		$found = false;
		$widgets = \Zotlabs\Extend\Widget::get();
		if ($widgets) {
			foreach ($widgets as $widget) {
				if (is_array($widget) && strtolower($widget[1]) === strtolower($name) && file_exists($widget[0])) {
					require_once($widget[0]);
					$found = true;
				}
			}
		}

		if (! $found) {
			if (file_exists('Zotlabs/SiteWidget/' . $clsname . '.php')) {
				require_once('Zotlabs/SiteWidget/' . $clsname . '.php');
			}
			elseif (file_exists('widget/' . $clsname . '/' . $clsname . '.php')) {
				require_once('widget/' . $clsname . '/' . $clsname . '.php');
			}
			elseif (file_exists('Zotlabs/Widget/' . $clsname . '.php')) {
				require_once('Zotlabs/Widget/' . $clsname . '.php');
			}
			else {
				$pth = theme_include($clsname . '.php');
				if ($pth) {
					require_once($pth);
				}
			}
		}

		if (class_exists($nsname)) {
			$x = new $nsname;
			$f = 'widget';
			if (method_exists($x,$f)) {
				return $x->$f($vars);
			}
		}

		$func = 'widget_' . trim($name);

		if (! function_exists($func)) {
			if (file_exists('widget/' . trim($name) . '.php')) {
				require_once('widget/' . trim($name) . '.php');
			}
			elseif (file_exists('widget/' . trim($name) . '/' . trim($name) . '.php')) {
				require_once('widget/' . trim($name) . '/' . trim($name) . '.php');
			}
			if (! function_exists($func)) {
				$theme_widget = $func . '.php';
				if (theme_include($theme_widget)) {
					require_once(theme_include($theme_widget));
				}
			}
		}

		if (function_exists($func)) {
			return $func($vars);
		}
	}


	function region($s,$region_name) {

		$s = str_replace('$region',$region_name,$s);

		$matches = [];

		$cnt = preg_match_all("/\[menu\](.*?)\[\/menu\]/ism", $s, $matches, PREG_SET_ORDER);
		if ($cnt) {
			foreach ($matches as $mtch) {
				$s = str_replace($mtch[0], $this->menu(trim($mtch[1])), $s);
			}
		}

		// menu class e.g. [menu=horizontal]my_menu[/menu] or [menu=tabbed]my_menu[/menu]
		// allows different menu renderings to be applied

		$cnt = preg_match_all("/\[menu=(.*?)\](.*?)\[\/menu\]/ism", $s, $matches, PREG_SET_ORDER);
		if ($cnt) {
			foreach ($matches as $mtch) {
				$s = str_replace($mtch[0],$this->menu(trim($mtch[2]),$mtch[1]),$s);
			}
		}
		$cnt = preg_match_all("/\[block\](.*?)\[\/block\]/ism", $s, $matches, PREG_SET_ORDER);
		if ($cnt) {
			foreach ($matches as $mtch) {
				$s = str_replace($mtch[0],$this->block(trim($mtch[1])),$s);
			}
		}

		$cnt = preg_match_all("/\[block=(.*?)\](.*?)\[\/block\]/ism", $s, $matches, PREG_SET_ORDER);
		if ($cnt) {
			foreach ($matches as $mtch) {
				$s = str_replace($mtch[0],$this->block(trim($mtch[2]),trim($mtch[1])),$s);
			}
		}

		$cnt = preg_match_all("/\[js\](.*?)\[\/js\]/ism", $s, $matches, PREG_SET_ORDER);
		if ($cnt) {
			foreach ($matches as $mtch) {
				$s = str_replace($mtch[0],$this->js(trim($mtch[1])),$s);
			}
		}

		$cnt = preg_match_all("/\[css\](.*?)\[\/css\]/ism", $s, $matches, PREG_SET_ORDER);
		if ($cnt) {
			foreach ($matches as $mtch) {
				$s = str_replace($mtch[0],$this->css(trim($mtch[1])),$s);
			}
		}

		$cnt = preg_match_all("/\[widget=(.*?)\](.*?)\[\/widget\]/ism", $s, $matches, PREG_SET_ORDER);
		if ($cnt) {
			foreach ($matches as $mtch) {
				$s = str_replace($mtch[0],$this->widget(trim($mtch[1]),$mtch[2]),$s);
			}
		}

		return $s;
	}


	/**
	 * @brief Registers a page template/variant for use by Comanche selectors.
	 *
	 * @param array $arr
	 *    'template' => template name
	 *    'variant' => array(
	 *           'name' => variant name
	 *           'desc' => text description
	 *           'regions' => array(
	 *               'name' => name
	 *               'desc' => text description
	 *           )
	 *    )
	 */
	function register_page_template($arr) {
		App::$page_layouts[$arr['template']] = array($arr['variant']);
		return;
	}

}