basic ical parser

1 files changed, 321 insertions, 0 deletions

diff --git a/library/ical.php b/library/ical.php
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+++ b/library/ical.php
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+<?php
+/**
+ * This PHP-Class should only read a iCal-File (*.ics), parse it and give an
+ * array with its content.
+ *
+ * PHP Version 5
+ *
+ * @category Parser
+ * @package  Ics-parser
+ * @author   Martin Thoma <info@martin-thoma.de>
+ * @license  http://www.opensource.org/licenses/mit-license.php  MIT License
+ * @version  SVN: <svn_id>
+ * @link     http://code.google.com/p/ics-parser/
+ * @example  $ical = new ical('MyCal.ics');
+ *           print_r( $ical->events() );
+ */
+
+error_reporting(E_ALL);
+
+/**
+ * This is the iCal-class
+ *
+ * @category Parser
+ * @package  Ics-parser
+ * @author   Martin Thoma <info@martin-thoma.de>
+ * @license  http://www.opensource.org/licenses/mit-license.php  MIT License
+ * @link     http://code.google.com/p/ics-parser/
+ *
+ * @param {string} filename The name of the file which should be parsed
+ * @constructor
+ */
+class ICal
+{
+    /* How many ToDos are in this ical? */
+    public  /** @type {int} */ $todo_count = 0;
+
+    /* How many events are in this ical? */
+    public  /** @type {int} */ $event_count = 0;
+
+    /* The parsed calendar */
+    public /** @type {Array} */ $cal;
+
+    /* Which keyword has been added to cal at last? */
+    private /** @type {string} */ $_lastKeyWord;
+
+    /**
+     * Creates the iCal-Object
+     *
+     * @param {string} $filename The path to the iCal-file
+     *
+     * @return Object The iCal-Object
+     */
+    public function __construct($filename)
+    {
+        if (!$filename) {
+            return false;
+        }
+       
+        $lines = file($filename, FILE_IGNORE_NEW_LINES | FILE_SKIP_EMPTY_LINES);
+        if (stristr($lines[0], 'BEGIN:VCALENDAR') === false) {
+            return false;
+        } else {
+            // TODO: Fix multiline-description problem (see http://tools.ietf.org/html/rfc2445#section-4.8.1.5)
+            foreach ($lines as $line) {
+                $line = trim($line);
+                $add  = $this->keyValueFromString($line);
+                if ($add === false) {
+                    $this->addCalendarComponentWithKeyAndValue($type, false, $line);
+                    continue;
+                }
+
+                list($keyword, $value) = $add;
+
+                switch ($line) {
+                // http://www.kanzaki.com/docs/ical/vtodo.html
+                case "BEGIN:VTODO":
+                    $this->todo_count++;
+                    $type = "VTODO";
+                    break;
+
+                // http://www.kanzaki.com/docs/ical/vevent.html
+                case "BEGIN:VEVENT":
+                    //echo "vevent gematcht";
+                    $this->event_count++;
+                    $type = "VEVENT";
+                    break;
+
+                //all other special strings
+                case "BEGIN:VCALENDAR":
+                case "BEGIN:DAYLIGHT":
+                    // http://www.kanzaki.com/docs/ical/vtimezone.html
+                case "BEGIN:VTIMEZONE":
+                case "BEGIN:STANDARD":
+                    $type = $value;
+                    break;
+                case "END:VTODO": // end special text - goto VCALENDAR key
+                case "END:VEVENT":
+                case "END:VCALENDAR":
+                case "END:DAYLIGHT":
+                case "END:VTIMEZONE":
+                case "END:STANDARD":
+                    $type = "VCALENDAR";
+                    break;
+                default:
+                    $this->addCalendarComponentWithKeyAndValue($type,
+                                                               $keyword,
+                                                               $value);
+                    break;
+                }
+            }
+            return $this->cal;
+        }
+    }
+
+    /**
+     * Add to $this->ical array one value and key.
+     *
+     * @param {string} $component This could be VTODO, VEVENT, VCALENDAR, ...
+     * @param {string} $keyword   The keyword, for example DTSTART
+     * @param {string} $value     The value, for example 20110105T090000Z
+     *
+     * @return {None}
+     */
+    public function addCalendarComponentWithKeyAndValue($component,
+                                                        $keyword,
+                                                        $value)
+    {
+        if ($keyword == false) {
+            $keyword = $this->last_keyword;
+            switch ($component) {
+            case 'VEVENT':
+                $value = $this->cal[$component][$this->event_count - 1]
+                                               [$keyword].$value;
+                break;
+            case 'VTODO' :
+                $value = $this->cal[$component][$this->todo_count - 1]
+                                               [$keyword].$value;
+                break;
+            }
+        }
+       
+        if (stristr($keyword, "DTSTART") or stristr($keyword, "DTEND")) {
+            $keyword = explode(";", $keyword);
+            $keyword = $keyword[0];
+        }
+
+        switch ($component) {
+        case "VTODO":
+            $this->cal[$component][$this->todo_count - 1][$keyword] = $value;
+            //$this->cal[$component][$this->todo_count]['Unix'] = $unixtime;
+            break;
+        case "VEVENT":
+            $this->cal[$component][$this->event_count - 1][$keyword] = $value;
+            break;
+        default:
+            $this->cal[$component][$keyword] = $value;
+            break;
+        }
+        $this->last_keyword = $keyword;
+    }
+
+    /**
+     * Get a key-value pair of a string.
+     *
+     * @param {string} $text which is like "VCALENDAR:Begin" or "LOCATION:"
+     *
+     * @return {array} array("VCALENDAR", "Begin")
+     */
+    public function keyValueFromString($text)
+    {
+        preg_match("/([^:]+)[:]([\w\W]*)/", $text, $matches);
+        if (count($matches) == 0) {
+            return false;
+        }
+        $matches = array_splice($matches, 1, 2);
+        return $matches;
+    }
+
+    /**
+     * Return Unix timestamp from ical date time format
+     *
+     * @param {string} $icalDate A Date in the format YYYYMMDD[T]HHMMSS[Z] or
+     *                           YYYYMMDD[T]HHMMSS
+     *
+     * @return {int}
+     */
+    public function iCalDateToUnixTimestamp($icalDate)
+    {
+        $icalDate = str_replace('T', '', $icalDate);
+        $icalDate = str_replace('Z', '', $icalDate);
+
+        $pattern  = '/([0-9]{4})';   // 1: YYYY
+        $pattern .= '([0-9]{2})';    // 2: MM
+        $pattern .= '([0-9]{2})';    // 3: DD
+        $pattern .= '([0-9]{0,2})';  // 4: HH
+        $pattern .= '([0-9]{0,2})';  // 5: MM
+        $pattern .= '([0-9]{0,2})/'; // 6: SS
+        preg_match($pattern, $icalDate, $date);
+
+        // Unix timestamp can't represent dates before 1970
+        if ($date[1] <= 1970) {
+            return false;
+        }
+        // Unix timestamps after 03:14:07 UTC 2038-01-19 might cause an overflow
+        // if 32 bit integers are used.
+        $timestamp = mktime((int)$date[4],
+                            (int)$date[5],
+                            (int)$date[6],
+                            (int)$date[2],
+                            (int)$date[3],
+                            (int)$date[1]);
+        return  $timestamp;
+    }
+
+    /**
+     * Returns an array of arrays with all events. Every event is an associative
+     * array and each property is an element it.
+     *
+     * @return {array}
+     */
+    public function events()
+    {
+        $array = $this->cal;
+        return $array['VEVENT'];
+    }
+
+    /**
+     * Returns a boolean value whether thr current calendar has events or not
+     *
+     * @return {boolean}
+     */
+    public function hasEvents()
+    {
+        return ( count($this->events()) > 0 ? true : false );
+    }
+
+    /**
+     * Returns false when the current calendar has no events in range, else the
+     * events.
+     *
+     * Note that this function makes use of a UNIX timestamp. This might be a
+     * problem on January the 29th, 2038.
+     * See http://en.wikipedia.org/wiki/Unix_time#Representing_the_number
+     *
+     * @param {boolean} $rangeStart Either true or false
+     * @param {boolean} $rangeEnd   Either true or false
+     *
+     * @return {mixed}
+     */
+    public function eventsFromRange($rangeStart = false, $rangeEnd = false)
+    {
+        $events = $this->sortEventsWithOrder($this->events(), SORT_ASC);
+
+        if (!$events) {
+            return false;
+        }
+
+        $extendedEvents = array();
+       
+        if ($rangeStart !== false) {
+            $rangeStart = new DateTime();
+        }
+
+        if ($rangeEnd !== false or $rangeEnd <= 0) {
+            $rangeEnd = new DateTime('2038/01/18');
+        } else {
+            $rangeEnd = new DateTime($rangeEnd);
+        }
+
+        $rangeStart = $rangeStart->format('U');
+        $rangeEnd   = $rangeEnd->format('U');
+
+       
+
+        // loop through all events by adding two new elements
+        foreach ($events as $anEvent) {
+            $timestamp = $this->iCalDateToUnixTimestamp($anEvent['DTSTART']);
+            if ($timestamp >= $rangeStart && $timestamp <= $rangeEnd) {
+                $extendedEvents[] = $anEvent;
+            }
+        }
+
+        return $extendedEvents;
+    }
+
+    /**
+     * Returns a boolean value whether thr current calendar has events or not
+     *
+     * @param {array} $events    An array with events.
+     * @param {array} $sortOrder Either SORT_ASC, SORT_DESC, SORT_REGULAR,
+     *                           SORT_NUMERIC, SORT_STRING
+     *
+     * @return {boolean}
+     */
+    public function sortEventsWithOrder($events, $sortOrder = SORT_ASC)
+    {
+        $extendedEvents = array();
+       
+        // loop through all events by adding two new elements
+        foreach ($events as $anEvent) {
+            if (!array_key_exists('UNIX_TIMESTAMP', $anEvent)) {
+                $anEvent['UNIX_TIMESTAMP'] =
+                            $this->iCalDateToUnixTimestamp($anEvent['DTSTART']);
+            }
+
+            if (!array_key_exists('REAL_DATETIME', $anEvent)) {
+                $anEvent['REAL_DATETIME'] =
+                            date("d.m.Y", $anEvent['UNIX_TIMESTAMP']);
+            }
+           
+            $extendedEvents[] = $anEvent;
+        }
+       
+        foreach ($extendedEvents as $key => $value) {
+            $timestamp[$key] = $value['UNIX_TIMESTAMP'];
+        }
+        array_multisort($timestamp, $sortOrder, $extendedEvents);
+
+        return $extendedEvents;
+    }
+}