path: root/ical_parser.php

<?php
// note from Jared: the _time suffix has been applied to all variables 
// that are timestamps to distinguish between them and Ymd format
// I did not change other variables to use this convention yet

// I started commenting the line above where $master_array gets written to
// I did this because I kept scrolling through looking for them so I decided to mark them

include("./init.inc.php");
include("./functions/date_add.php");
include("./functions/date_functions.php");
include("./functions/draw_functions.php");
include("./functions/overlapping_events.php");

$fillTime = $day_start;
$day_array = array ();
while ($fillTime != "2400") {
	array_push ($day_array, $fillTime);
	ereg ("([0-9]{2})([0-9]{2})", $fillTime, $dTime);
	$fill_h = $dTime[1];
	$fill_min = $dTime[2];
	$fill_min = sprintf("%02d", $fill_min + $gridLength);
	if ($fill_min == 60) {
		$fill_h = sprintf("%02d", ($fill_h + 1));
		$fill_min = "00";
	}
	$fillTime = $fill_h . $fill_min;
}


// what date we want to get data for (for day calendar)
if (!$getdate) $getdate = date("Ymd");
ereg ("([0-9]{4})([0-9]{2})([0-9]{2})", $getdate, $day_array2);
$this_day = $day_array2[3];
$this_month = $day_array2[2];
$this_year = $day_array2[1];

// Start the session
//session_start();
//if (($aYear != $this_year) || ($use_sessions != "yes") || (!is_array($aArray))) {
//echo "not using sessions";


// open the iCal file, read it into a string
$fp = @fopen($filename, "r");
$contents = @fread ($fp, filesize ($filename));
@fclose ($fp);


// turn that string into an array
$contents = ereg_replace("\n ", "", $contents);
$contents = split ("\n", $contents);

// auxiliary array for determining overlaps of events
$overlap_array = array ();

// parse our new array
foreach($contents as $line) {
	if (strstr($line, "BEGIN:VEVENT")) {
		$start_time = "";
		$end_time = "";
		$end_day = "";
		$summary = "";
		$allday_start = "";
		$allday_end = "";
		$start = "";
		$end = "";
		$the_duration = "";
		$beginning = "";
		$rrule_array = "";
		$start_of_vevent = "";
		$end_of_vevent = "";
		$interval = "";
		$number = "";
		$except_dates = array();
		$except_times = array();
		$first_duration = TRUE;
		$bymonthday = "";
		$count = 1000000;
	} elseif (strstr($line, "END:VEVENT")) {
		
		// Clean out \n's and other slashes
		$summary = str_replace("\\n", "<br>", $summary);
		$summary = stripslashes($summary);
		$description = str_replace("\\n", "<br>", $description);
		$mArray_begin = mktime (0,0,0,1,1,$this_year);
		$mArray_end = mktime (0,0,0,1,10,($this_year + 1));
				
		if ($start_time != "") {
			ereg ("([0-9]{2})([0-9]{2})", $start_time, $time);
			ereg ("([0-9]{2})([0-9]{2})", $end_time, $time2);
			$length = ($time2[1]*60+$time2[2]) - ($time[1]*60+$time[2]);
			
			$drawKey = drawEventTimes($start_time, $end_time);
			ereg ("([0-9]{2})([0-9]{2})", $drawKey["draw_start"], $time3);
			$hour = $time3[1];
			$minute = $time3[2];
		}
		
		
		// Handling of the all day events	
		if (($allday_start != "") && ($rrule_array == "")) {
			$start = strtotime("$allday_start");
			$end = strtotime("$allday_end");
			if (($end > $mArray_begin) && ($end < $mArray_end)) {
				while ($start != $end) {
					$start_date = date("Ymd", $start);
					$master_array[($start_date)][("-1")][]= array ("event_text" => "$summary", "description" => $description);
					$start = strtotime("+1 day", $start);
				}
			}
		}
		
		
		// Handling of the recurring events, RRULE
		// This will be quite a bit of work, thats for sure.
		if (is_array($rrule_array)) {
			if ($allday_start != "") {
				$rrule_array["START_DAY"] = $allday_start;
				$rrule_array["END_DAY"] = $allday_end;
				$rrule_array["END"] = "end";
				$recur_start = $allday_start;
			} else {
				$rrule_array["START_DATE"] = $start_date;
				$rrule_array["START_TIME"] = $start_time;
				$rrule_array["END_TIME"] = $end_time;
				$rrule_array["END"] = "end";
			}
			//print_r($rrule_array);
			foreach ($rrule_array as $key => $val) {
				if ($key == "FREQ") {
					if ($val == "YEARLY") {
						$interval = "yyyy";
					} elseif ($val == "MONTHLY") {
						$interval = "m";
					} elseif ($val == "WEEKLY") {
						$interval = "ww";
					} elseif ($val == "DAILY") {
						$interval = "d";
					} elseif ($val == "HOURLY") {
						$interval = "h";
					} elseif ($val == "MINUTELY") {
						$interval = "n";
					} elseif ($val == "SECONDLY") {
						$interval = "s";
					}		
				} elseif ($key == "COUNT") 		{
					$count = $val;
				
				} elseif ($key == "UNTIL") 		{
					$until = ereg_replace("T", "", $val);
					ereg ("([0-9]{4})([0-9]{2})([0-9]{2})([0-9]{0,2})([0-9]{0,2})", $until, $regs);
					$year = $regs[1];
					$month = $regs[2];
					$day = $regs[3];
					$until = strtotime("$year$month$day");
					
				} elseif ($key == "INTERVAL")	{
					$number = $val;
				
				} elseif ($key == "BYSECOND") 	{
					$bysecond = $val;
					$bysecond = split (",", $bysecond);
				
				} elseif ($key == "BYMINUTE") 	{
					$byminute = $val;
					$byminute = split (",", $byminute);
				
				} elseif ($key == "BYHOUR")		{
					$byhour = $val;
					$byhour = split (",", $byhour);
				
				} elseif ($key == "BYDAY") 		{
					$byday = $val;
					$byday = split (",", $byday);
				
				} elseif ($key == "BYMONTHDAY") {
					$bymonthday = $val;
					$bymonthday = split (",", $bymonthday);
					//print_r ($bymonthday);
				
				} elseif ($key == "BYYEARDAY") 	{
					$byyearday = $val;
					$byyearday = split (",", $byyearday);
				
				} elseif ($key == "BYWEEKNO") 	{
					$byweekno = $val;
					$byweekno = split (",", $byweekno);
				
				} elseif ($key == "BYMONTH") 	{
					$bymonth = $val;
					$bymonth = split (",", $bymonth);
				
				} elseif ($key == "BYSETPOS") 	{
					$bysetpos = $val;
				
				} elseif ($key == "WKST") 		{
					$wkst = $val;
				
				} elseif ($key == "END")		{
					
					if ($allday_start != "") {
						
						// Since we hit the end of the RRULE array, lets do something.
						// Below handles yearly, montly, weekly, daily all-day events.
						// $start_of_vevent is the date the recurring event starts.
						// $end_of_vevent is the date the recurring event stops.
						// $count and $count_to check for the COUNT feature
						// $until checks for the UNTIL feature, makes sure we don't recur past it.
						 
						$start_of_vevent = strtotime("$allday_start");
						$end_of_vevent = strtotime("$allday_end");
						$count_to = 0;
						if (!$until) $until = $mArray_end;
						if ($start_of_vevent < $mArray_end) {
							do {
								// This steps through each day of a multiple all-day event and adds to master array
								// Every all day event should pass through here at least once if its recurring.
								$start = $start_of_vevent;
								$end = $end_of_vevent;
								while ($start != $end) {
									$start_date = date("Ymd", $start);
									if (($end > $mArray_begin) && ($end < $mArray_end)) {
										$master_array[($start_date)][("-1")][]= array ("event_text" => "$summary", "description" => $description);
									}
									$start = strtotime("+1 day", $start);
								}
								$start_of_vevent = DateAdd ($interval,  $number, $start_of_vevent);
								$end_of_vevent = DateAdd ($interval,  $number, $end_of_vevent);
								$count_to++;
							} while (($start_of_vevent < $mArray_end) && ($count != $count_to) && ($start_of_vevent < $until)); 
						}
					
					// Let's take care of recurring events that are not all day events
					// DAILY and WEEKLY recurrences seem to work fine. Need feedback.
					// Known bug, doesn't look at UNTIL or COUNT yet.
					} else {
					
						// again, $parse_to_year is set to January 10 of the upcoming year
						$parse_to_year_time  = mktime(0,0,0,1,10,($this_year + 1));
						$start_date_time = strtotime($start_date);
						
						// depending on which view we're looking at, we do one month or one week
						// one day is more difficult, I think, so I wrapped that into the week. We'll have to
						// add another case for "year" once that's added.
						if ($current_view == "month") {
							$start_range_time = strtotime("$this_year-$this_month-01");
							$end_range_time = strtotime("+1 month +1 week", $start_range_time);
						} else {
							$start_range_time = strtotime(dateOfWeek($getdate, substr($week_start_day, 0, 2)));
							$end_range_time = strtotime("+1 week", $start_range_time);
						}
						
						// if $until isn't set yet, we set it to the end of our range we're looking at
						if (!$until) $until = $end_range_time;
						$end_date_time = $until;
						
						// If the $end_range_time is less than the $start_date_time, or $start_range_time is greater
						// than $end_date_time, we may as well forget the whole thing
						// It doesn't do us any good to spend time adding data we aren't even looking at
						// this will prevent the year view from taking way longer than it needs to
						if ($end_range_time >= $start_date_time && $start_range_time <= $end_date_time) {
						
							// if the beginning of our range is less than the start of the item, we may as well set it equal to it
							if ($start_range_time < $start_date_time) $start_range_time = $start_date_time;
							if ($end_range_time > $end_date_time) $end_range_time = $end_date_time;
				
							// initialze the time we will increment
							$next_range_time = $start_range_time;
							
							$count_to = 0;
							// start at the $start_range and go until we hit the end of our range.
							while (($next_range_time >= $start_range_time) && ($next_range_time <= $end_range_time) && ($count_to != $count)) {
								
								// handling WEEKLY events here
								if ($rrule_array["FREQ"] == "WEEKLY") {

									// use weekCompare to see if we even have this event this week
									$diff_weeks = weekCompare(date("Ymd",$next_range_time), $start_date);
									if ($diff_weeks < $count) {
										if ($week_diff % $number == 0) {
											$interval = $number;
											// loop through the days on which this event happens
											foreach($byday as $day) {
											
												// use my fancy little function to get the date of each day
												$next_date = dateOfWeek(date("Ymd", $next_range_time),$day);
												$next_date_time = strtotime($next_date);
												
												if (($next_date_time > $start_date_time) && ($next_date_time <= $end_date_time) && ($count_to != $count) && !in_array($next_date, $except_dates)) {
													// add it to the array if it passes inspection, it allows the first time to be
													// written by the master data writer (hence the > instead of >=) otherwise we can special case these
													// before, the first one would get entered twice and show up twice
													// $next_date can fall up to a week behind $next_range_time because of how dateOfWeek works
													// so we have to check this again. It uses $except_dates so it doesn't add to $master_array
													// on days that have been deleted by the user
// check for overlapping events
													$nbrOfOverlaps = checkOverlap();
// writes to $master array here
													$master_array[($next_date)][($hour.$minute)][] = array ("event_start" => $start_time, "event_text" => $summary, "event_end" => $end_time, "event_length" => $length, "event_overlap" => $nbrOfOverlaps, "description" => $description);
												}
											}
										} else {
											$interval = 1;
										}
										$next_range_time = strtotime("+$interval week", $next_range_time);
									} else {
										// end the loop because we aren't going to write this event anyway
										$count_to = $count;
									}
									
								
								// handling DAILY events here
								} elseif ($rrule_array["FREQ"] == "DAILY") {

									// use dayCompare to see if we even have this event this day
									$diff_days = dayCompare(date("Ymd",$next_range_time), $start_date);
									if ($diff_days < $count) {
										if ($diff_days % $number == 0) {
											$interval = $number;
											$next_date = date("Ymd", $next_range_time);
											$next_date_time = strtotime($next_date);
											
											if (($next_date_time > $start_date_time) && ($next_date_time <= $end_date_time) && ($count_to != $count) && !in_array($next_date, $except_dates)) {
												// same general concept as the WEEKLY recurrence
// check for overlapping events
												$nbrOfOverlaps = checkOverlap();
// writes to $master array here
												$master_array[($next_date)][($hour.$minute)][] = array ("event_start" => $start_time, "event_text" => $summary, "event_end" => $end_time, "event_length" => $length, "event_overlap" => $nbrOfOverlaps, "description" => $description);
											}
										} else {
											$interval = 1;
										}
										$next_range_time = strtotime("+$interval day", $next_range_time);
									} else {
										// end the loop because we aren't going to write this event anyway
										$count_to = $count;
									}
									
									
								// handling MONTHLY events here
								} elseif ($rrule_array["FREQ"] == "MONTHLY") {
									$next_range_time = strtotime(date("Y-m-01", $next_range_time));
									// use monthCompare to see if we even have this event this month
									
									$diff_months = monthCompare(date("Ymd",$next_range_time), $start_date);
									if ($diff_months < $count) {
										if ($diff_months % $number == 0) {
											$interval = $number;
											
											// month has two cases, either $bymonthday or $byday
											if (is_array($bymonthday)) {
											
												// loop through the days on which this event happens
												foreach($bymonthday as $day) {
													if ($day != "0") {
														$next_date_time = strtotime(date("Y-m-",$next_range_time).$day);
														$next_date = date("Ymd", $next_date_time);
														if (($next_date_time > $start_date_time) && ($next_date_time <= $end_date_time) && ($count_to != $count) && !in_array($next_date, $except_dates)) {
															// same general concept as the WEEKLY recurrence
// check for overlapping events	
															$nbrOfOverlaps = checkOverlap();
// writes to $master array here
															$master_array[($next_date)][($hour.$minute)][] = array ("event_start" => $start_time, "event_text" => $summary, "event_end" => $end_time, "event_length" => $length, "event_overlap" => $nbrOfOverlaps, "description" => $description);
														}
													}
												}
												
											// our other case
											} else {
												// loop through the days on which this event happens
												foreach($byday as $day) {
													ereg ("([0-9]{1})([A-Z]{2})", $day, $byday_arr);
													$nth = $byday_arr[1]-1;
													$on_day = two2threeCharDays($byday_arr[2]);
													$next_date_time = strtotime("$on_day +$nth week", $next_range_time);
													$next_date = date("Ymd", $next_date_time);
													if (($next_date_time > $start_date_time) && ($next_date_time <= $end_date_time) && ($count_to != $count) && !in_array($next_date, $except_dates)) {
														// same general concept as the WEEKLY recurrence
// check for overlapping events	
														$nbrOfOverlaps = checkOverlap();
// writes to $master array here
														$master_array[($next_date)][($hour.$minute)][] = array ("event_start" => $start_time, "event_text" => $summary, "event_end" => $end_time, "event_length" => $length, "event_overlap" => $nbrOfOverlaps, "description" => $description);
													}
												}
											}
										} else {
											$interval = 1;
										}
										$next_range_time = strtotime("+$interval month", $next_range_time);
									} else {
										// end the loop because we aren't going to write this event anyway
										$count_to = $count;
									}
									
									
								// anything else we need to end the loop
								} else {
									$next_range_time = $end_range_time + 100;
									$count_to = $count;
								}
							}
						}
					}
				}	
			}
		}
	
	// Let's write all the data to the master array
	if ($start_time != "") {
// check for overlapping events
		$nbrOfOverlaps = checkOverlap();

// writes to $master array here
		$master_array[($start_date)][($hour.$minute)][] = array ("event_start" => $start_time, "event_text" => $summary, "event_end" => $end_time, "event_length" => $length, "event_overlap" => $nbrOfOverlaps, "description" => $description);
	}
		

		
		
		
	} else {
		
		$field = "";
		$data = "";
		
		sscanf($line, "%[^:]:%[^\n]", &$field, &$data);
		
		if(strstr($field, "DTSTART;TZID")) {
			$data = ereg_replace("T", "", $data);
			ereg ("([0-9]{4})([0-9]{2})([0-9]{2})([0-9]{0,2})([0-9]{0,2})", $data, $regs);
			$year = $regs[1];
			$month = $regs[2];
			$day = $regs[3];
			$hour = $regs[4];
			$minute = $regs[5];
			
			$start_date = $year . $month . $day;
			$start_time = $hour . $minute;

		} elseif (strstr($field, "DTEND;TZID")) {
			$data = ereg_replace("T", "", $data);
			ereg ("([0-9]{4})([0-9]{2})([0-9]{2})([0-9]{0,2})([0-9]{0,2})", $data, $regs);
			$year = $regs[1];
			$month = $regs[2];
			$day = $regs[3];
			$hour = $regs[4];
			$minute = $regs[5];
		
			$end_day = $year . $month . $day;
			$end_time = $hour . $minute;
			
		} elseif (strstr($field, "EXDATE;TZID")) {
			$data = ereg_replace("T", "", $data);
			ereg ("([0-9]{4})([0-9]{2})([0-9]{2})([0-9]{0,2})([0-9]{0,2})", $data, $regs);
			$year = $regs[1];
			$month = $regs[2];
			$day = $regs[3];
			$hour = $regs[4];
			$minute = $regs[5];
		
			$except_dates[] = $year . $month . $day;
			$except_times[] = $hour . $minute;
			
		} elseif (strstr($field, "SUMMARY")) {
			$summary = $data;
			
		} elseif (strstr($field, "DESCRIPTION")) {
			$description = $data;	
		
		} elseif (strstr($field, "X-WR-CALNAME")) {
			$calendar_name = $data;
		
		} elseif (strstr($field, "DTSTART;VALUE=DATE")) {
			$allday_start = $data;
			// echo "$allday_start";
		
		} elseif (strstr($field, "DTEND;VALUE=DATE")) {
			$allday_end = $data;
			
		} elseif (strstr($field, "DURATION")) {
			
			if (($first_duration = TRUE) && (!strstr($field, "=DURATION"))) {
				ereg ("^P([0-9]{1,2})?([W,D]{0,1})?(T)?([0-9]{1,2})?(H)?([0-9]{1,2})?(M)?([0-9]{1,2})?(S)?", $data, $duration);
				if ($duration[2] = "W") {
					$weeks = $duration[1];
				} else {
					$days = $duration[1];
				}
				$hours = $duration[4];
				$minutes = $duration[6];
				$seconds = $duration[8];
				$the_duration = ($weeks * 60 * 60 * 24 * 7) + ($days * 60 * 60 * 24) + ($hours * 60 * 60) + ($minutes * 60) + ($seconds);
				$beginning = (strtotime($start_time) + $the_duration);
				$end_time = date ("Hi", $beginning);
				$first_duration = FALSE;
			}	
			
		} elseif (strstr($field, "RRULE")) {
			// $data = "RRULE:FREQ=YEARLY;INTERVAL=2;BYMONTH=1;BYDAY=SU;BYHOUR=8,9;BYMINUTE=30";
			$data = ereg_replace ("RRULE:", "", $data);
			$rrule = split (";", $data);
			foreach ($rrule as $recur) {
				ereg ("(.*)=(.*)", $recur, $regs);
				$rrule_array[$regs[1]] = $regs[2];
			}	
		} elseif (strstr($field, "ATTENDEE")) {
			$attendee = $data;
			// echo "$attendee";
			
		}
	}
}
// Sort the array by absolute date.
if (is_array($master_array)) { 
	ksort($master_array);
	reset($master_array);
}

// Store information in the session
/*if ($use_sessions == "yes") {
	session_start();
	session_register( "aArray", "aYear", "aLanguage", "aCalendar" );
	$aArray = $master_array;
	$aYear = $this_year;
	$aLanguage = $language;
	$aCalendar = $cal;
}*/


// End the session
//}

//If you want to see the values in the arrays, uncomment below.
//print "<pre>";
//print_r($master_array);
//print_r($overlap_array);
//print_r($day_array);
//print_r($rrule);			
//print "</pre>";
	
					
?>