Club Drupal

<?php

/**

 * @file

 * Utility functions for Date iCal. Many of these are re-writes of buggy Date

 * module code.

 */

/**

 * Parse the repeat data into date values.

 *

 * This is a re-write of date_repeat_build_dates() which fixes it's bugs

 * regarding multi-property RDATEs and EXDATEs.

 */

function _date_ical_get_repeat_dates($field_name, $repeat_data, $item, $source) {

  module_load_include('inc', 'date_api', 'date_api_ical');

  $field_info = field_info_field($field_name);

  $rrule_values = _date_ical_parse_repeat_rule($repeat_data['RRULE']);

  //$exrule_values = _date_ical_parse_repeat_rule($repeat_data['EXRULE']);

  $rdates = _date_ical_parse_repeat_dates($repeat_data['RDATE']);

  $exdates = _date_ical_parse_repeat_dates($repeat_data['EXDATE']);

  // By the time we get here, the start and end dates have been

  // adjusted back to UTC, but we want localtime dates to do

  // things like '+1 Tuesday', so adjust back to localtime.

  $timezone = date_get_timezone($field_info['settings']['tz_handling'], $item['timezone']);

  $timezone_db = date_get_timezone_db($field_info['settings']['tz_handling']);

  $start = new DateObject($item['value'], $timezone_db, date_type_format($field_info['type']));

  $start->limitGranularity($field_info['settings']['granularity']);

  if ($timezone != $timezone_db) {

    date_timezone_set($start, timezone_open($timezone));

  }

  if (!empty($item['value2']) && $item['value2'] != $item['value']) {

    $end = new DateObject($item['value2'], date_get_timezone_db($field_info['settings']['tz_handling']), date_type_format($field_info['type']));

    $end->limitGranularity($field_info['settings']['granularity']);

    date_timezone_set($end, timezone_open($timezone));

  }

  else {

    $end = $start;

  }

  $duration = $start->difference($end);

  $start_datetime = date_format($start, DATE_FORMAT_DATETIME);

  if (!empty($rrule_values['UNTIL']['datetime'])) {

    // TODO: The spec says that UNTIL must be specified in UTC, but I think

    // this may not be followd by all feed creators. It may be a good idea to

    // support optionally assuming the date has the same TZID as DTSTART.

    $end = date_ical_date($rrule_values['UNTIL'], $timezone);

    $end_datetime = date_format($end, DATE_FORMAT_DATETIME);

  }

  elseif (!empty($rrule_values['COUNT'])) {

    $end_datetime = NULL;

  }

  else {

    // No UNTIL and no COUNT?

    return array();

  }

  // Convert the EXDATE and RDATE values to datetime strings.

  // Even though exdates and rdates can be specified to the second, Date

  // Repeat's code checks them by comparing them to the date value only.

  $exceptions = array();

  foreach ($exdates as $exception) {

    $date = date_ical_date($exception, $timezone);

    $exceptions[] = date_format($date, 'Y-m-d');

  }

  $additions = array();

  foreach ($rdates as $rdate) {

    $date = date_ical_date($rdate, $timezone);

    $additions[] = date_format($date, 'Y-m-d');

  }

  // TODO: EXRULE.

  $date_repeat_compatible_rrule = "{$repeat_data['RRULE']}\n{$repeat_data['RDATE']}\n{$repeat_data['EXDATE']}";

  $calculated_dates = date_repeat_calc($date_repeat_compatible_rrule, $start_datetime, $end_datetime, $exceptions, $timezone, $additions);

  $repeat_dates = array();

  foreach ($calculated_dates as $delta => $date) {

    // date_repeat_calc always returns DATE_DATETIME dates, which is

    // not necessarily $field_info['type'] dates.

    // Convert returned dates back to db timezone before storing.

    $date_start = new DateObject($date, $timezone, DATE_FORMAT_DATETIME);

    $date_start->limitGranularity($field_info['settings']['granularity']);

    date_timezone_set($date_start, timezone_open($timezone_db));

    $date_end = clone($date_start);

    date_modify($date_end, '+' . $duration . ' seconds');

    $repeat_dates[$delta] = array(

      'value' => date_format($date_start, date_type_format($field_info['type'])),

      'value2' => date_format($date_end, date_type_format($field_info['type'])),

      'offset' => date_offset_get($date_start),

      'offset2' => date_offset_get($date_end),

      'timezone' => $timezone,

      'rrule' => $date_repeat_compatible_rrule,

    );

  }

  return $repeat_dates;

}

/**

 * Parse an rrule or exrule string.

 *

 * @return array

 *   Array in the form of PROPERTY => array(VALUES)

 *   PROPERTIES include FREQ, INTERVAL, COUNT, BYDAY, BYMONTH, BYYEAR, UNTIL.

 */

function _date_ical_parse_repeat_rule($repeat_rule_string) {

  module_load_include('inc', 'date_api', 'date_api_ical');

  $repeat_rule_string = preg_replace('/(R|EX)RULE.*:/', '', $repeat_rule_string);

  $items = array('DATA' => $repeat_rule_string);

  foreach (explode(';', $repeat_rule_string) as $recur_val) {

    list($key, $value) = explode('=', $recur_val);

    // Must be some kind of invalid data.

    if (empty($key) || empty($value)) {

      continue;

    }

    // These keys never have multiple values.

    if (in_array($key, array('UNTIL', 'FREQ', 'INTERVAL', 'COUNT', 'WKST'))) {

      if ($key == 'UNTIL') {

        // This is a function from the date_api module, not date_ical.

        $value = date_ical_parse_date('', $value);

      }

    }

    else {

      // The rest can be multi-value csv strings.

      $value = explode(',', $value);

    }

    $items[$key] = $value;

  }

  return $items;

}

/**

 * Parses an iCal RDATE or EXDATE, including multi-property rules.

 *

 * @param string $repeat_date_string

 *   An RDATE or EXDATE property string, e.g.

 *   "EXDATE;TZID=America/Los_Angeles:20130415T180000,20130422T180000"

 *   Can be multiple EXDATE or RDATE properties, separated by newlines.

 *

 * @return array

 *   An array of dates returned by date_ical_parse_date().

 */

function _date_ical_parse_repeat_dates($repeat_date_string) {

  module_load_include('inc', 'date_api', 'date_api_ical');

  $properties = explode("\n", str_replace("\r\n", "\n", $repeat_date_string));

  $parsed_dates = array();

  foreach ($properties as $property) {

    $matches = array();

    if (preg_match('/(R|EX)DATE([^:]*):(.*)/', $property, $matches)) {

      $params = $matches[2];

      foreach (explode(',', $matches[3]) as $date) {

        $parsed_dates[] = date_ical_parse_date($params, $date);

      }

    }

  }

  return $parsed_dates;

}