<?php
// $Id: mobileplugin.module,v 1.9 2010/01/26 17:01:42 teemule Exp $

/**
 * Mobile Plugin is a mobile optimization package for Drupal.
 * Nitro FX Oy, Finland 2009
 * Mikko Hyytiainen, Teemu Lehtinen
 */

define('MOBILEPLUGIN_FULL_GROUP', 'full');
define('MOBILEPLUGIN_MOBILE_GROUP', 'mobile');
define('MOBILEPLUGIN_ENABLE', 'enable mobile plugin for');

/**
 * Returns the permissions used by the module.
 * @return permissions array
 */
function mobileplugin_perm() {
	return array(MOBILEPLUGIN_ENABLE);
}

/**
* Displays help and module information.
* @param path
* @param arg
* @return help text for the section
*/
function mobileplugin_help($path, $arg) {
	$output = '';
	switch ($path) {
	case 'admin/help#mobileplugin':
		$output = '<p>' .  t('Provides a mobile optimized view to the site') . '</p>';
		break;
	}
	return $output;
}

/** 
 * Logic to select a group and set the theme at page init time.
 */
function mobileplugin_init() {
	global $mobileplugin_group, $mobileplugin_host_defined;
	if (!user_access(MOBILEPLUGIN_ENABLE)) {
		return;
	}
	$mobile_host = variable_get('mobileplugin_mobile_domain', '');
	$mobileplugin_host_defined = strlen($mobile_host) > 0;
	$cached_state = false;

	// Check for session and cookie.
	if (isset($_SESSION['mobileplugin_group'])) {
		$cached_state = $_SESSION['mobileplugin_group'];
	} else if (isset($_COOKIE['mobileplugin_group'])) {
		$cached_state = $_COOKIE['mobileplugin_group'];
	}
	if ($cached_state) {
		list($group, $touch) = explode(',', $cached_state);
		if (intval($touch)) {
			_mobileplugin_add_class('touchscreen');
		}
		$mobileplugin_group = _mobileplugin_validate_group($group);
		_mobileplugin_set_theme($mobileplugin_group);
		return;
	}

	// Check for configured mobile domain.
	if ($mobileplugin_host_defined) {
		if($_SERVER['HTTP_HOST'] != $mobile_host) {
			$mobileplugin_group = MOBILEPLUGIN_FULL_GROUP;
			return;
		}
		$mobileplugin_group = MOBILEPLUGIN_MOBILE_GROUP;
	} else {
		$mobileplugin_group = MOBILEPLUGIN_FULL_GROUP;
	}

	// Do device detection.
	$touch = 0;
	if (variable_get('mobileplugin_detection', true)) {
		list($mobileplugin_group, $touch) = _mobileplugin_detect_group($mobileplugin_group);
		if ($touch) {
			_mobileplugin_add_class('touchscreen');
		}
	}

	// Store group to a cookie.
	setcookie('mobileplugin_group', $mobileplugin_group .','. ($touch ? '1' : '0'), 0, '/');
	_mobileplugin_set_theme();
}

/** 
 * Attaches pages and actions to menu paths.
 * @return the menu items
 */
function mobileplugin_menu() {
	$items = array();
	$items['mobileplugin/switch'] = array(
		'page callback' => 'mobileplugin_switch',
		'access arguments' => array('access content'),
		'type' => MENU_CALLBACK
	);
	$items['admin/build/mobileplugin'] = array(
		'title' => 'Mobile Plugin',
		'description' => 'Set up a mobile site',
		'page callback' => 'drupal_get_form',
		'page arguments' => array('mobileplugin_admin_settings'),
		'file' => 'mobileplugin-admin.inc',
		'access arguments' => array('administer site configuration'),
		'type' => MENU_NORMAL_ITEM
	);
	$items['admin/build/mobileplugin/settings'] = array(
		'title' => 'Settings',
		'file' => 'mobileplugin-admin.inc',
		'access arguments' => array('administer site configuration'),
		'type' => MENU_DEFAULT_LOCAL_TASK,
		'weight' => -10
	);
	$items['admin/build/mobileplugin/groups'] = array(
		'title' => 'Device groups',
		'page callback' => 'mobileplugin_groups',
		'file' => 'mobileplugin-admin.inc',
		'access arguments' => array('administer site configuration'),
		'type' => MENU_LOCAL_TASK,
		'weight' => 1
	);
	$items['admin/build/mobileplugin/groups/edit'] = array(
		'title' => 'Edit group',
		'page callback' => 'drupal_get_form',
		'page arguments' => array('mobileplugin_groups_form'),
		'file' => 'mobileplugin-admin.inc',
		'access arguments' => array('administer site configuration'),
		'type' => MENU_CALLBACK
	);
	$items['admin/build/mobileplugin/groups/filter'] = array(
		'title' => 'Filter group css and js',
		'page callback' => 'drupal_get_form',
		'page arguments' => array('mobileplugin_filter_form'),
		'file' => 'mobileplugin-admin.inc',
		'access arguments' => array('administer site configuration'),
		'type' => MENU_CALLBACK
	);
	$items['admin/build/mobileplugin/rules'] = array(
		'title' => 'Detection rules',
		'page callback' => 'mobileplugin_rules',
		'file' => 'mobileplugin-admin.inc',
		'access arguments' => array('administer site configuration'),
		'type' => MENU_LOCAL_TASK,
		'weight' => 2
	);
	$items['admin/build/mobileplugin/rules/edit'] = array(
		'title' => 'Edit rule',
		'page callback' => 'drupal_get_form',
		'page arguments' => array('mobileplugin_rules_form'),
		'file' => 'mobileplugin-admin.inc',
		'access arguments' => array('administer site configuration'),
		'type' => MENU_CALLBACK
	);
	$items['admin/build/mobileplugin/test'] = array(
		'page callback' => 'mobileplugin_test_group',
		'file' => 'mobileplugin-admin.inc',
		'access arguments' => array('administer site configuration'),
		'type' => MENU_CALLBACK
	);
	$items['admin/build/mobileplugin/debug'] = array(
		'title' => 'Device debug',
		'page callback' => 'mobileplugin_debug',
		'file' => 'mobileplugin-admin.inc',
		'access arguments' => array('administer site configuration'),
		'type' => MENU_LOCAL_TASK,
		'weight' => 3
	);
	return $items;
}

/**
 * Checks if a mobile version is served.
 * @return true if a mobile version is served
 */
function mobileplugin_is_mobile() {
	global $mobileplugin_group;
	return $mobileplugin_group != MOBILEPLUGIN_FULL_GROUP;
}

/**
 * Gets the current group settings.
 * @return the current group settings
 */
function mobileplugin_get_group_setup() {
	global $mobileplugin_group;
	static $group_setup;
	if ($group_setup) {
		return $group_setup;
	}
	$allgroups = _mobileplugin_get_groups();
	$group_setup = $allgroups[$mobileplugin_group];
	return $group_setup;
}

/**
* Switches from the mobile to full view and vice versa.
*/
function mobileplugin_switch() {
	global $mobileplugin_group;
	if ($mobileplugin_group != MOBILEPLUGIN_FULL_GROUP) {
		$group = MOBILEPLUGIN_FULL_GROUP;
		$touch = false;
	} else {
		list($group, $touch) = _mobileplugin_detect_group(MOBILEPLUGIN_MOBILE_GROUP);
	}
	setcookie('mobileplugin_group', $group . ',' . ($touch ? '1' : '0'), time() + 8640000, '/');
	drupal_goto(drupal_get_destination());
}

/**
 * Sets the configured theme for the given group.
 */
function _mobileplugin_set_theme() {
	global $mobileplugin_group, $custom_theme;
	if ($group != MOBILEPLUGIN_FULL_GROUP) {
		$grouplist = _mobileplugin_get_groups();
		$custom_theme = $grouplist[$mobileplugin_group]['theme'];
	}
}

/**
 * Adds a css class for the page.
 * @param name a css class name
 */
function _mobileplugin_add_class($name = null) {
	global $mobileplugin_class;
	if (!is_null($name)) {
		$mobileplugin_class .= ' '.$name;
	}
	return $mobileplugin_class;
}

/**
 * Detects the device group.
 * @return the device group detected
 */
function _mobileplugin_detect_group($default_group = MOBILEPLUGIN_FULL_GROUP) {
	$device = null;
	$rules = _mobileplugin_get_rules();
	foreach ($rules as $r) {

		// Get property value to compare.
		$v = null;
		if ($r['capability'] == 'USERAGENT') {
			$v = $_SERVER['HTTP_USER_AGENT'];
		} else if (module_exists('wurfl')) {
			if (is_null($device)) {
				$device = wurfl_get_requestingDevice();
			}
			if ($device) {
				if ($r['capability'] == 'ID') {
					$v = $device->id;
				} else {
					$v = $device->getCapability($r['capability']);
				}
			}
		} else if ($r['capability'] == 'is_wireless_device') {
			module_load_include('inc', 'mobileplugin', 'mobileplugin-detect');
			$v = mobileplugin_lite_detection() ? 'true' : 'false';
		}

		// Find matches.
		if (!is_null($v) && _mobileplugin_detect_match($v, $r['operator'], $r['value'])) {
			if ($r['group_name'] == 'no') {
				return array($default_group, false);
			}
			$gt = explode(',', $r['group_name']);
			if (count($gt) > 1) {
				return array($gt[0], $gt[1] > 0);
			}
			$t = false;
			if (module_exists('wurfl')) {
				if (is_null($device)) {
					$device = wurfl_get_requestingDevice();
				}
				$t = ($device && $device->getCapability('is_wireless_device') == 'true'
					&& $device->getCapability('pointing_method') == 'touchscreen');
			}
			return array($gt[0], $t);
		}
	}
	return array($default_group, false);
}

/**
 * Compares values.
 */
function _mobileplugin_detect_match($value, $op, $compare) {
	$arr = explode("\n", $compare);
	switch ($op) {
	case '==':
		foreach ($arr as $a) {
			if ($value == $a) {
				return true;
			}
		}
		return false;
	case '!=':
		foreach ($arr as $a) {
			if ($value == $a) {
				return false;
			}
		}
		return true;
	case '<=':
		foreach ($arr as $a) {
			if ($value <= $a) {
				return true;
			}
		}
		return false;
	case '>=':
		foreach ($arr as $a) {
			if ($value >= $a) {
				return true;
			}
		}
		return false;
	case '=~':
		foreach ($arr as $a) {
			if (stripos($value, trim($a)) !== false) {
				return true;
			}
		}
		return false;
	case '!=~':
		foreach ($arr as $a) {
			if (stripos($value, $a) !== false) {
				return false;
			}
		}
		return true;
	}
	return false;
}

/**
 * Validates the group is in the configured groups.
 * @param group a group name
 * @return a valid group name
 */
function _mobileplugin_validate_group($group) {
	$g = strtolower($group);
	$grouplist = _mobileplugin_get_groups();
	if (isset($grouplist[$g])) {
		return $g;
	}
	return MOBILEPLUGIN_FULL_GROUP;
}

/**
 * Gets the configured groups.
 * @return configured groups and their settings
 */
function _mobileplugin_get_groups() {
	static $grouplist;
	if ($grouplist) {
		return $grouplist;
	}
	if ($c = cache_get('mobileplugin_grouplist', 'cache')) {
		$grouplist = $c->data;
	} else {
		$grouplist = array();
		$result = db_query('select name,theme,data from {mobileplugin_groups}');
		while ($row = db_fetch_array($result)) {
			_mobileplugin_group_setup_in($row);
			$grouplist[$row['name']] = $row;
		}
		cache_set('mobileplugin_grouplist', $grouplist, 'cache');
	}
	return $grouplist;
}

/**
 * Processes the group settings for use.
 * @param group a loaded group settings array
 */
function _mobileplugin_group_setup_in(&$group) {
	if ($group['data']) {
		$group = array_merge($group, unserialize($group['data']));
	}
	unset($group['data']);
}

/**
 * Gets the configured rules from the database.
 * @return the detection rules in ordered array
 */
function _mobileplugin_get_rules() {
	static $rulelist;
	if ($rulelist) {
		return $rulelist;
	}
	if ($c = cache_get('mobileplugin_rulelist', 'cache')) {
		$rulelist = $c->data;
	} else {
		$rulelist = array();
		$n = 0;
		$result = db_query('select capability,operator,value,group_name from {mobileplugin_rules} order by weight asc');
		while ($row = db_fetch_array($result)) {
			$rulelist[$n] = $row;
			$n++;
		}
		cache_set('mobileplugin_rulelist', $rulelist, 'cache');
	}
	return $rulelist;
}

/**
 * Optimizes node content.
 * @param node a node object
 * @param op the current operation
 * @param teaser a flag of teaser view
 * @param page a flag of page view 
 */
function mobileplugin_nodeapi(&$node, $op, $teaser = false, $page = true) {
	global $mobileplugin_group;
	if ($op == 'view' && $mobileplugin_group != MOBILEPLUGIN_FULL_GROUP) {
		$element_names = array_filter(array_keys($node->content), 'element_child');
		$cache_key = 'mobileplugin_optimized:'. $node->nid .':'. ($teaser ? 't' : 'f') .':'. $mobileplugin_group;
		if ($c = cache_get($cache_key, 'cache_page')) {
			$values = $c->data;
		} else {
			$values = array();
			foreach ($element_names as $name) {
				$values[$name] = $node->content[$name]['#value'];
			}
			_mobileplugin_optimize($values);
			cache_set($cache_key, $values, 'cache_page');
		}
		foreach ($element_names as $name) {
			$node->content[$name]['#value'] = $values[$name];
		}
	} else if($op == 'update' || $op == 'delete') {
		cache_clear_all('mobileplugin_optimized:'. $node->nid .':', 'cache_page', true);
	}
}

/**
 * Optimizes comment content.
 * @param comment a comment object
 * @param op the current operation
 */
function mobileplugin_comment(&$comment, $op) {
	global $mobileplugin_group;
	if ($op == 'view' && $mobileplugin_group != MOBILEPLUGIN_FULL_GROUP) {
		$cache_key = 'mobileplugin_optimized_cid:'. $comment->cid .':'. $mobileplugin_group;
		if ($c = cache_get($cache_key, 'cache_page')) {
			$value = $c->data;
		} else {
			$map = array('value' => $comment->comment);
			_mobileplugin_optimize($map);
			$value = $map['value'];
			cache_set($cache_key, $value, 'cache_page');
		}
		$comment->comment = $value;
	} else if ($op == 'update' || $op == 'delete') {
		cache_clear_all('mobileplugin_optimized_cid:'. $comment->cid .':', 'cache_page', true);
	}
}

/**
 * Optimizes html content for mobile view.
 * @param map an associative array of html markup to optimize
 */
function _mobileplugin_optimize(&$map) {
	require_once(dirname(__FILE__) . '/simple_html_dom.php');

	// Prepare group configuration.
	$group_setup = mobileplugin_get_group_setup();
	$imgact = _mobileplugin_get_setup_val($group_setup, 'imageact', 'scale');
	$width = $height = 180;
	if ($imgact == 'scale') {
		list($w, $h) = explode('x', _mobileplugin_get_setup_val($group_setup, 'imagesize', ''));
		$w = intval(trim($w));
		$h = intval(trim($h));
		if ($w > 0 && $h > 0) {
			$width = $w;
			$height = $h;
		}
	}
	$bw = intval(_mobileplugin_get_setup_val($group_setup, 'breakwords', 30));

	// Optimize given key values.
	$values = array();
	foreach ($map as $key => $value) {
		if (!empty($value)) {
			$dom = str_get_html($value);
			module_invoke_all('mobileplugin_optimize_dom', $group_setup, $dom);

			// Do image processing.
			$dom = str_get_html($dom->save());
			switch ($imgact) {
			case 'scale':
				foreach ($dom->find('img') as $i) {
					$res = _mobileplugin_image_scaled($i->src, $width, $height);
					if (is_array($res)) {
						$i->width = $res[0];
						$i->height = $res[1] > 0 ? $res[1] : null;
					} else {
						$i->src = base_path() . $res;
						$i->width = null;
						$i->height = null;
					}
				}
				break;
			case 'remove':
				foreach ($dom->find('img') as $i) {
					$i = null;
				}
				break;
			default:
				break;
			}

			// Break long words.
			if ($bw > 0) {
				foreach ($dom->find('text') as $t) {
					if ($t->parent()->tag != 'script') {
						$t->outertext = _mobileplugin_break_long_words($t->outertext, $bw);
					}
				}
			}
			$map[$key] = $dom->save();
		}
	}
}

/**
 * Gets a setting or a default value. Usable helper for modules implementing mobileplugin hooks.
 * @param group a group settings array
 * @param key a stored key
 * @param default a default value
 * @return a stored value or default
 */
function _mobileplugin_get_setup_val(&$group, $key, $default) {
	if (isset($group[$key])) {
		return $group[$key];
	}
	return $default;
}

/**
 * Scales an image down if possible.
 * @param url an image url
 * @param width a maximum width
 * @param height a maximum height
 * @return new image url or size array
 */
function _mobileplugin_image_scaled($url, $width, $height) {
	$copydir = file_directory_path() . '/mobileplugin';
	$sizedir = $copydir . '/' . $width . 'x' . $height;
	$basename = md5($url) . substr($url, strrpos($url, '.'));
	$targetname = $sizedir . '/' . $basename;
	if (file_exists($targetname)) {
		return $targetname;
	}

	// Get the image through http to be sure.
	$urlinfo = parse_url($url);
	if (!$urlinfo['host'] || $urlinfo['host'] == $_SERVER['SERVER_NAME']) {
		$bpath = base_path();
		$bpathl = strlen($bpath);
		if (substr($urlinfo['path'], 0, $bpathl) == $bpath) {
			$file = urldecode(substr($urlinfo['path'], $bpathl));

			// Try to activate imagecache.
			if (!file_exists($file)) {
				drupal_http_request($urlinfo['path'], array(), 'GET', null, 1);
				if (!file_exists($file)) {
					return array($width, 0);
				}
			}

			// Scale using imageapi if available.
			file_check_directory($copydir, true);
			file_check_directory($sizedir, true);
			drupal_get_messages();
			if (module_exists('imageapi') && imageapi_default_toolkit()) {
				$image = imageapi_image_open($file);
				if ($image->info['width'] > 0) {
					if (imageapi_image_scale($image, $width, $height) && imageapi_image_close($image, $targetname)) {
						return $targetname;
					}
				}
			}
			if (image_scale($file, $targetname, $width, $height)) {
				return $targetname;
			}
		}
	}
	return array($width, 0);
}

/**
 * Adds suggested word breaks to long words.
 * @param str a source string
 * @param max a maximum word length
 * @return the result string
 */
function _mobileplugin_break_long_words($str, $max) {
	$res = '';
	$l = strlen($str);
	$c = 0;
	for ($i = 0; $i < $l; $i++) {
		$ch = $str{$i};
		$res .= $ch;
		if ($ch == ' ' || $ch == "\t" || $ch == '\n') {
			$c = 0;
		} else {
			$c++;
			if ($c == $max) {
				$res .= '<wbr/>';
				$c = 0;
			}
		}
	}
	return $res;
}

/**
 * Gets filtered css markup.
 * @return filtered css markup
 */
function _mobileplugin_filter_css(&$css = array()) {
	$group_setup = mobileplugin_get_group_setup();
	$filtercss = _mobileplugin_get_setup_val($group_setup, 'filtercss', array('sites/all/themes/', 'themes/', 'sites/default/files/'));
	foreach ($css as $media => $types) {
		foreach ($types as $type => $files) {
			foreach ($files as $file => $preprocess) {
				if (!_mobileplugin_is_inside_paths($file, $filtercss)) {
					unset($css[$media][$type][$file]);
				}
			}
		}
	}
	return drupal_get_css($css);
}

/**
 * Gets filtered header js markup.
 * @return filtered header js markup
 */
function _mobileplugin_filter_js() {
	$group_setup = mobileplugin_get_group_setup();
	$filterjs = _mobileplugin_get_setup_val($group_setup, 'filterjs', array());
	$js = drupal_add_js();
	foreach ($js as $type => $files) {
		switch ($type) {
		case 'setting':
			if (!_mobileplugin_is_inside_paths('misc/drupal.js', $filterjs)) {
				unset($js['setting']);
			}
			break;
		case 'inline':
			break;
		default:
			foreach ($files as $file => $info) {
				if (!_mobileplugin_is_inside_paths($file, $filterjs)) {
					unset($js[$type][$file]);
				}
			}
		}
	}
	return drupal_get_js('header', $js);
}

/**
 * Tests if a target is inside the given paths.
 * @param target a target path or file
 * @param paths a list of paths
 * @return true if the target is inside the given paths
 */
function _mobileplugin_is_inside_paths($target, &$paths) {
	foreach ($paths as $p) {
		$lp = strlen($p);
		if (strlen($target) >= $lp && $p == substr($target, 0, $lp)) {
			return true;
		}
	}
	return false;
}

/**
* Implements a drupal block.
* @param op the block operation
* @param delta the block delta
* @returns the block data
*/
function mobileplugin_block($op = 'list', $delta = 0) {
	if ($op == 'list') {
		$blocks[0]['info'] = t('Switch to and from mobile version');
		$blocks[0]['cache'] = BLOCK_NO_CACHE;
		return $blocks;
	} else if ($op == 'view') {
		$block = array();
		switch($delta) {
		case 0:
			if (user_access(MOBILEPLUGIN_ENABLE)) {
				$switch = _mobileplugin_get_switch();
				$block = array('content' => theme('mobileplugin_switch', $switch['url'], $switch['title']));
			}
			break;
		}
		return $block;
	}
}

/**
 * Defines full/mobile switch.
 */
function _mobileplugin_get_switch() {
	global $mobileplugin_host_defined, $mobileplugin_group;
	static $switch;
	if ($switch) {
		return $switch;
	}
	$switch = array();
	if ($mobileplugin_group == MOBILEPLUGIN_FULL_GROUP) {
		if ($mobileplugin_host_defined) {
			$switch['url'] = 'http://' . variable_get('mobileplugin_mobile_domain', '');
		} else {
			$switch['url'] = 'mobileplugin/switch';
		}
		$switch['title'] = t('Show mobile version');
	} else {
		if ($mobileplugin_host_defined) {
			$switch['url'] = 'http://' . variable_get('mobileplugin_full_domain', '');
		} else {
			$switch['url'] = 'mobileplugin/switch';
		}
		$switch['title'] = t('Show full browser version');
	}
	return $switch;
}

/**
 * Register theme functions.
 * @return theme function array
 */
function mobileplugin_theme() {
	return array(
		'mobileplugin_switch' => array(
			'arguments' => array($url => '', $title => '')
		)
	);
}

/**
* Themes full/mobile switch block.
* @param url a url to switch the theme
* @param title a title for the operation
*/
function theme_mobileplugin_switch($url, $title) {
	return l($title, $url, array('query' => drupal_get_destination()));
}