system/libraries/Calendar_Event.php

   1 <?php defined('SYSPATH') OR die('No direct access allowed.');
   2 /**
   3  * Calendar event observer class.
   4  *
   5  * $Id: Calendar_Event.php 3917 2009-01-21 03:06:22Z zombor $
   6  *
   7  * @package    Calendar
   8  * @author     Kohana Team
   9  * @copyright  (c) 2007-2008 Kohana Team
  10  * @license    http://kohanaphp.com/license.html
  11  */
  12 class Calendar_Event extends Event_Observer {
  13
  14         // Boolean conditions
  15         protected $booleans = array
  16         (
  17                 'current',
  18                 'weekend',
  19                 'first_day',
  20                 'last_day',
  21                 'last_occurrence',
  22                 'easter',
  23         );
  24
  25         // Rendering conditions
  26         protected $conditions = array();
  27
  28         // Cell classes
  29         protected $classes = array();
  30
  31         // Cell output
  32         protected $output = '';
  33
  34         /**
  35          * Adds a condition to the event. The condition can be one of the following:
  36          *
  37          * timestamp       - UNIX timestamp
  38          * day             - day number (1-31)
  39          * week            - week number (1-5)
  40          * month           - month number (1-12)
  41          * year            - year number (4 digits)
  42          * day_of_week     - day of week (1-7)
  43          * current         - active month (boolean) (only show data for the month being rendered)
  44          * weekend         - weekend day (boolean)
  45          * first_day       - first day of month (boolean)
  46          * last_day        - last day of month (boolean)
  47          * occurrence      - occurrence of the week day (1-5) (use with "day_of_week")
  48          * last_occurrence - last occurrence of week day (boolean) (use with "day_of_week")
  49          * easter          - Easter day (boolean)
  50          * callback        - callback test (boolean)
  51          *
  52          * To unset a condition, call condition with a value of NULL.
  53          *
  54          * @chainable
  55          * @param   string  condition key
  56          * @param   mixed   condition value
  57          * @return  object
  58          */
  59         public function condition($key, $value)
  60         {
  61                 if ($value === NULL)
  62                 {
  63                         unset($this->conditions[$key]);
  64                 }
  65                 else
  66                 {
  67                         if ($key === 'callback')
  68                         {
  69                                 // Do nothing
  70                         }
  71                         elseif (in_array($key, $this->booleans))
  72                         {
  73                                 // Make the value boolean
  74                                 $value = (bool) $value;
  75                         }
  76                         else
  77                         {
  78                                 // Make the value an int
  79                                 $value = (int) $value;
  80                         }
  81
  82                         $this->conditions[$key] = $value;
  83                 }
  84
  85                 return $this;
  86         }
  87
  88         /**
  89          * Add a CSS class for this event. This can be called multiple times.
  90          *
  91          * @chainable
  92          * @param   string  CSS class name
  93          * @return  object
  94          */
  95         public function add_class($class)
  96         {
  97                 $this->classes[$class] = $class;
  98
  99                 return $this;
 100         }
 101
 102         /**
 103          * Remove a CSS class for this event. This can be called multiple times.
 104          *
 105          * @chainable
 106          * @param   string  CSS class name
 107          * @return  object
 108          */
 109         public function remove_class($class)
 110         {
 111                 unset($this->classes[$class]);
 112
 113                 return $this;
 114         }
 115
 116         /**
 117          * Set HTML output for this event.
 118          *
 119          * @chainable
 120          * @param   string  HTML output
 121          * @return  object
 122          */
 123         public function output($str)
 124         {
 125                 $this->output = $str;
 126
 127                 return $this;
 128         }
 129
 130         /**
 131          * Add a CSS class for this event. This can be called multiple times.
 132          *
 133          * @chainable
 134          * @param   string  CSS class name
 135          * @return  object
 136          */
 137         public function notify($data)
 138         {
 139                 // Split the date and current status
 140                 list ($month, $day, $year, $week, $current) = $data;
 141
 142                 // Get a timestamp for the day
 143                 $timestamp = mktime(0, 0, 0, $month, $day, $year);
 144
 145                 // Date conditionals
 146                 $condition = array
 147                 (
 148                         'timestamp'   => (int) $timestamp,
 149                         'day'         => (int) date('j', $timestamp),
 150                         'week'        => (int) $week,
 151                         'month'       => (int) date('n', $timestamp),
 152                         'year'        => (int) date('Y', $timestamp),
 153                         'day_of_week' => (int) date('w', $timestamp),
 154                         'current'     => (bool) $current,
 155                 );
 156
 157                 // Tested conditions
 158                 $tested = array();
 159
 160                 foreach ($condition as $key => $value)
 161                 {
 162                         // Test basic conditions first
 163                         if (isset($this->conditions[$key]) AND $this->conditions[$key] !== $value)
 164                                 return FALSE;
 165
 166                         // Condition has been tested
 167                         $tested[$key] = TRUE;
 168                 }
 169
 170                 if (isset($this->conditions['weekend']))
 171                 {
 172                         // Weekday vs Weekend
 173                         $condition['weekend'] = ($condition['day_of_week'] === 0 OR $condition['day_of_week'] === 6);
 174                 }
 175
 176                 if (isset($this->conditions['first_day']))
 177                 {
 178                         // First day of month
 179                         $condition['first_day'] = ($condition['day'] === 1);
 180                 }
 181
 182                 if (isset($this->conditions['last_day']))
 183                 {
 184                         // Last day of month
 185                         $condition['last_day'] = ($condition['day'] === (int) date('t', $timestamp));
 186                 }
 187
 188                 if (isset($this->conditions['occurrence']))
 189                 {
 190                         // Get the occurance of the current day
 191                         $condition['occurrence'] = $this->day_occurrence($timestamp);
 192                 }
 193
 194                 if (isset($this->conditions['last_occurrence']))
 195                 {
 196                         // Test if the next occurance of this date is next month
 197                         $condition['last_occurrence'] = ((int) date('n', $timestamp + 604800) !== $condition['month']);
 198                 }
 199
 200                 if (isset($this->conditions['easter']))
 201                 {
 202                         if ($condition['month'] === 3 OR $condition['month'] === 4)
 203                         {
 204                                 // This algorithm is from Practical Astronomy With Your Calculator, 2nd Edition by Peter
 205                                 // Duffett-Smith. It was originally from Butcher's Ecclesiastical Calendar, published in
 206                                 // 1876. This algorithm has also been published in the 1922 book General Astronomy by
 207                                 // Spencer Jones; in The Journal of the British Astronomical Association (Vol.88, page
 208                                 // 91, December 1977); and in Astronomical Algorithms (1991) by Jean Meeus.
 209
 210                                 $a = $condition['year'] % 19;
 211                                 $b = (int) ($condition['year'] / 100);
 212                                 $c = $condition['year'] % 100;
 213                                 $d = (int) ($b / 4);
 214                                 $e = $b % 4;
 215                                 $f = (int) (($b + 8) / 25);
 216                                 $g = (int) (($b - $f + 1) / 3);
 217                                 $h = (19 * $a + $b - $d - $g + 15) % 30;
 218                                 $i = (int) ($c / 4);
 219                                 $k = $c % 4;
 220                                 $l = (32 + 2 * $e + 2 * $i - $h - $k) % 7;
 221                                 $m = (int) (($a + 11 * $h + 22 * $l) / 451);
 222                                 $p = ($h + $l - 7 * $m + 114) % 31;
 223
 224                                 $month = (int) (($h + $l - 7 * $m + 114) / 31);
 225                                 $day = $p + 1;
 226
 227                                 $condition['easter'] = ($condition['month'] === $month AND $condition['day'] === $day);
 228                         }
 229                         else
 230                         {
 231                                 // Easter can only happen in March or April
 232                                 $condition['easter'] = FALSE;
 233                         }
 234                 }
 235
 236                 if (isset($this->conditions['callback']))
 237                 {
 238                         // Use a callback to determine validity
 239                         $condition['callback'] = call_user_func($this->conditions['callback'], $condition, $this);
 240                 }
 241
 242                 $conditions = array_diff_key($this->conditions, $tested);
 243
 244                 foreach ($conditions as $key => $value)
 245                 {
 246                         if ($key === 'callback')
 247                         {
 248                                 // Callbacks are tested on a TRUE/FALSE basis
 249                                 $value = TRUE;
 250                         }
 251
 252                         // Test advanced conditions
 253                         if ($condition[$key] !== $value)
 254                                 return FALSE;
 255                 }
 256
 257                 $this->caller->add_data(array
 258                 (
 259                         'classes' => $this->classes,
 260                         'output'  => $this->output,
 261                 ));
 262         }
 263
 264         /**
 265          * Find the week day occurrence for a specific timestamp. The occurrence is
 266          * relative to the current month. For example, the second Saturday of any
 267          * given month will return "2" as the occurrence. This is used in combination
 268          * with the "occurrence" condition.
 269          *
 270          * @param   integer  UNIX timestamp
 271          * @return  integer
 272          */
 273         protected function day_occurrence($timestamp)
 274         {
 275                 // Get the current month for the timestamp
 276                 $month = date('m', $timestamp);
 277
 278                 // Default occurrence is one
 279                 $occurrence = 1;
 280
 281                 // Reduce the timestamp by one week for each loop. This has the added
 282                 // benefit of preventing an infinite loop.
 283                 while ($timestamp -= 604800)
 284                 {
 285                         if (date('m', $timestamp) !== $month)
 286                         {
 287                                 // Once the timestamp has gone into the previous month, the
 288                                 // proper occurrence has been found.
 289                                 return $occurrence;
 290                         }
 291
 292                         // Increment the occurrence
 293                         $occurrence++;
 294                 }
 295         }
 296
 297 } // End Calendar Event