<?php
// This function returns a list of all calendars that the current user
// has access to. Basically, all local calendars found in the calendar
// directory, plus any webcals listed in the configuration file, but
// excluding blacklisted calendars and locked calendars which the user,
// if logged in, does not have access to.
//
// $username		= The username. Empty if no username provided.
// $password		= The password. Empty if no password provided.
// $cal_filename	= The calendar name without .ics.
// $admin			= True if this is an administrative request, in
//					  which case all local calendars only will be
//					  returned.
function availableCalendars($username, $password, $cal_filename, $admin = false) {
	// Import globals.
	global $list_webcals, $blacklisted_cals, $locked_cals, $locked_map, $apache_map, $lang, $_SERVER, $phpiCal_config;
	// Create the list of available calendars.
	$calendars = array();

	// Grab any HTTP authentication.
	unset($http_user);
	if ((isset($_SERVER['PHP_AUTH_USER'])) && ($phpiCal_config->allow_login == 'yes')) {
		$http_user = $_SERVER['PHP_AUTH_USER'];
	}

	// Grab the list of unlocked calendars.
	$unlocked_cals = array();
	if (isset($locked_map["$username:$password"])) {
		$unlocked_cals = $locked_map["$username:$password"];
	}
	// Make a local copy of the requested calendars.
	if (!is_array($cal_filename))
		$cal_filename_local = array($cal_filename);
	else
		$cal_filename_local = $cal_filename;

	// Create the list of available calendars.
	$calendars = array();
	
	// This array keeps track of paths we need to search.
	$search_paths = array($phpiCal_config->calendar_path);
	// Add web calendars.
	if ($cal_filename_local[0] == $phpiCal_config->ALL_CALENDARS_COMBINED || $admin)	{
		if (!isset($http_user) && !$admin) {
			foreach ($list_webcals as $file) {
				// Make sure the URL ends with .ics.
				if (!is_string($file)) continue;			
				// Add this calendar.
				array_push($calendars, $file);
			}
		}
	}	
	// Set some booleans that will dictate our search.
	$find_all = ($cal_filename_local[0] == $phpiCal_config->ALL_CALENDARS_COMBINED || $admin);
	
	// Process all search paths.
	while (!empty($search_paths)) {
		// Read the next search path.
		$search_path = array_pop($search_paths);
			
		// This array keeps track of filenames we need to look at.
		$files = array();
		
		// Build the list of files we need to check.
		//
		// We do a full directory search if we are supposed to find all
		// calendars, the calendar we're looking for may be in a
		// subdirectory, or we are supporting the iCal repository format.
		// The latter is necessary because the calendar name cannot be
		// used to identify the calendar filename.
		if ($find_all || $phpiCal_config->recursive_path == 'yes' || $phpiCal_config->support_ical == 'yes') {
			// Open the directory.
			$dir_handle = opendir($search_path)
				or die(error(sprintf($lang['l_error_path'], $search_path), implode(',', $cal_filename)));
			if ($dir_handle === false)
				die(error(sprintf($lang['l_error_path'], $search_path), implode(',', $cal_filename)));
				
			// Add each file in the directory that does not begin with a dot.
			while (false !== ($file = readdir($dir_handle))) {
				// Make sure this is not a dot file.
				if (preg_match("/^\./", $file)) continue;
				array_push($files, "$search_path/$file");
			}
		} else {
			// The file process block below expects actual filenames. So
			// we have to append '.ics' to the passed in calendar names.
			foreach ($cal_filename_local as $filename) {
				array_push($files, "$search_path/$filename.ics");
			}
		}
		
		// Process files.
		foreach ($files as $file) {
			// Push directories onto the search paths if recursive paths is
			// turned on.
			if (is_dir($file)) {
				if ($phpiCal_config->recursive_path == 'yes') array_push($search_paths, $file);
				continue;
			}			
			// Make sure the file is real.
			if (!is_file($file)) continue;
			// Remove any php files.
			if (preg_match("/^.*\.php$/i", $file)) continue;
			# remove publish log file 
			if ($file == 'publish_log.txt') continue;
			// Make sure this is not a blacklisted calendar.
			$cal_name = getCalendarName($file); 
			if (in_array($cal_name, $blacklisted_cals)) continue;
			// If HTTP authenticated, make sure this calendar is available
			// to the user.
			if (isset($http_user) && isset($apache_map[$http_user]) && !in_array($cal_name, $apache_map[$http_user])) continue;

			// Make sure this calendar is not locked.
			if (!$admin && in_array($cal_name, $locked_cals) && !in_array($cal_name, $unlocked_cals)) continue;
			
			// Add this calendar if we're looking for it, and remove it's name
			// from the local list because we've found it.
			if ($find_all || in_array($cal_name, $cal_filename_local)) {
				array_push($calendars, $file);
				$cal_filename_local = array_diff($cal_filename_local, array($cal_name));				
				// If the local list is empty, we're done.
				if (empty($cal_filename_local))	break 2;
			}
		}
	}
	// Return the sorted calendar list.
	natcasesort($calendars);
	return $calendars;
}

// This function returns the result of the availableCalendars function
// but only includes the calendar names.
//
// $username		= The username. Empty if no username provided.
// $password		= The password. Empty if no password provided.
// $cal_filename	= The calendar name without .ics.
// $admin			= True if this is an administrative request, in
//					  which case all local calendars only will be
//					  returned.
function availableCalendarNames($username, $password, $cal_filename, $admin = false) {
	// Grab the available calendar paths.
	$calendars = availableCalendars($username, $password, $cal_filename, $admin);

	// Strip the paths off the calendars.
	foreach (array_keys($calendars) as $key) {
		$calendars[$key] = getCalendarName($key);
	}
	
	// Return the sorted calendar names.
	natcasesort($calendars);
	return $calendars;
}

// This function returns the calendar name for the specified calendar path.
//
// $cal_path	= The path to the calendar file.
function getCalendarName($cal_path) {
	global $phpiCal_config;
		
	// If iCal is supported, check the directory for an Info.plist.
	if ($phpiCal_config->support_ical == 'yes') {
		// Look for the Info.plist file.
		$plist_filename = dirname($cal_path)."/Info.plist";
		if (is_file($plist_filename)) {
			// Read the Info.plist.
			$handle = fopen($plist_filename, 'r');
			$contents = fread($handle, filesize($plist_filename));
			fclose($handle);
						
			// Pull out the calendar name.
			$num_matches = preg_match("/<key>Title<\/key>\s*?<string>(.+?)<\/string>/i", $contents, $matches);
			if ($num_matches > 0)
				return $matches[1];
		}
	}
	
	// At this point, just pull the name off the file.
	$name = str_replace(".ics", '', basename($cal_path));
	if ((substr($cal_path, 0, 7) == 'http://') ||
		(substr($cal_path, 0, 8) == 'https://') ||
		(substr($cal_path, 0, 9) == 'webcal://')) {
		$name = urldecode($name);
	}
	return $name;
}

// This function prints out the calendars available to the user, for
// selection. Should be enclosed within a <select>...</select>, which
// is not printed out by this function.
//
// $cals	= The calendars (entire path, e.g. from availableCalendars).
function display_ical_list($cals, $pick=FALSE) {
	global $cal, $current_view, $getdate, $lang, $calendar_lang, $all_cal_comb_lang, $cal_filelist, $cal_displaynames, $list_webcals, $phpiCal_config, $master_array;
	// Print each calendar option.
	$return = '';

	$all_cals = false;
	if (count($cals) > 1) $all_cals = true;

	foreach ($cals as $cal_tmp) {
		// Format the calendar path for display.
		//
		$cal_displayname_tmp = '';
		$search_idx = array_search($cal_tmp, $cal_filelist);
		if (is_numeric($search_idx)) {
			$cal_displayname_tmp = $cal_displaynames[$search_idx];
		}
		else if ((substr($cal_tmp, 0, 7) == 'http://') ||
			(substr($cal_tmp, 0, 8) == 'https://') ||
			(substr($cal_tmp, 0, 9) == 'webcal://')) {
			$cal_tmp2 = str_replace('webcal://', 'http://', $cal_tmp);
			$cal_tmp2 = str_replace('https://',  'http://', $cal_tmp2);
			$num = 1;
			foreach ($master_array[-4] as $master_cal) {
				if ($master_cal['filename'] == $cal_tmp2) {
					$cal_displayname_tmp = $master_array[-3][$num];
					break;
				}
				$num++;
			}
		}
		else {
			# pull the name from the $cal_tmp file
			$ifile = @fopen($cal_tmp, 'r');
			if ($ifile == FALSE) exit(error($lang['l_error_cantopen'], $cal_tmp));
			while (!feof($ifile)) {
				$line = fgets($ifile, 1024);
				$line = trim($line);
				if (preg_match ("/([^:]+):(.*)/", $line, $regs)){
					$field = $regs[1];
					$data = $regs[2];
					$property = $field;
					$prop_pos = strpos($property,';');
					if ($prop_pos !== false) $property = substr($property,0,$prop_pos);
					$property = strtoupper($property);
					if ($property == "X-WR-CALNAME"){
						$cal_displayname_tmp = stripslashes($data);
						break;
					}
				}	
				#stop reading if we find an event or timezone before there's a name
				if ($line == "BEGIN:VTIMEZONE" ||$line == "BEGIN:VEVENT") break;
			}
			@fclose($ifile);
		}
		if (empty($cal_displayname_tmp)) {
			// Only display the calendar name, replace all instances of "32" with " ",
			// and remove the .ics suffix.
			$cal_displayname_tmp = getCalendarName($cal_tmp);
			#$cal_displayname_tmp = str_replace('32', ' ', $cal_displayname_tmp);
		}

		// If this is a webcal, add 'Webcal' to the display name.
		if (preg_match("/^(https?|webcal):\/\//i", $cal_tmp)) {
			$cal_displayname_tmp .= " Webcal";
		}

		// Otherwise, remove all the path information, since that should
		// not be used to identify local calendars. Also add the calendar
		// label to the display name.
		else {
			// Strip path and .ics suffix.
			$cal_tmp = getCalendarName($cal_tmp);
			// Add calendar label.
			$cal_displayname_tmp .= " $calendar_lang";
		}

		// Encode the calendar path.
		$cal_encoded_tmp = urlencode($cal_tmp);
		if(in_array($cal_tmp, $list_webcals)){
			$cal_encoded_tmp = md5($phpiCal_config->salt.$cal_tmp);;
		}

		// Try to detect unselected calendars
		if (!in_array($cal_encoded_tmp, explode(",", $cal))) $all_cals = false;

		// Display the option.
		//
		// The submitted calendar will be encoded, and always use http://
		// if it is a webcal. So that is how we perform the comparison when
		// trying to figure out if this is the selected calendar.
		if($pick) {
			if (in_array($cal_encoded_tmp, explode(",", $cal)) || count($cals) == count(explode(",", $cal))) {
				$return .= "<option value=\"$cal_encoded_tmp\" selected=\"selected\">$cal_displayname_tmp</option>\n";
			} else {
				$return .= "<option value=\"$cal_encoded_tmp\">$cal_displayname_tmp</option>\n";
			}
		} else {
			if ($cal_encoded_tmp == $cal || $cal_encoded_tmp == urldecode($cal)) {
				$return .= "<option value=\"$current_view.php?cal=$cal_encoded_tmp&amp;getdate=$getdate\" selected=\"selected\">$cal_displayname_tmp</option>";
			} else {
				$return .= "<option value=\"$current_view.php?cal=$cal_encoded_tmp&amp;getdate=$getdate\">$cal_displayname_tmp</option>";	
			}
		}
	}			

	// option to open all (non-web) calenders together
	if (!$pick) {
		if ($all_cals || $cal == $phpiCal_config->ALL_CALENDARS_COMBINED) {
			$return .=  "<option value=\"$current_view.php?cal=$phpiCal_config->ALL_CALENDARS_COMBINED&amp;getdate=$getdate\" selected=\"selected\">$all_cal_comb_lang</option>";
		} else {
			$return .=  "<option value=\"$current_view.php?cal=$phpiCal_config->ALL_CALENDARS_COMBINED&amp;getdate=$getdate\">$all_cal_comb_lang</option>";
		}
	}

	return $return;
}