functions/date.php

   1 <?php
   2
   3 /**
   4  * date.php
   5  *
   6  * Takes a date and parses it into a usable format.  The form that a
   7  * date SHOULD arrive in is:
   8  *       <Tue,> 29 Jun 1999 09:52:11 -0500 (EDT)
   9  * (as specified in RFC 822) -- 'Tue' is optional
  10  *
  11  * @copyright &copy; 1999-2006 The SquirrelMail Project Team
  12  * @license http://opensource.org/licenses/gpl-license.php GNU Public License
  13  * @version $Id$
  14  * @package squirrelmail
  15  * @subpackage date
  16  */
  17
  18 /**
  19  * dependency information
  20  * - none
  21  */
  22
  23 /**
  24  * Corrects a time stamp to be the local time.
  25  *
  26  * @param int stamp the timestamp to adjust
  27  * @param string tzc the timezone correction
  28  * @return int the corrected timestamp
  29  */
  30 function getGMTSeconds($stamp, $tzc) {
  31     /* date couldn't be parsed */
  32     if ($stamp == -1) {
  33         return -1;
  34     }
  35     /* timezone correction, expressed as `shhmm' */
  36     switch($tzc)
  37     {
  38         case 'Pacific':
  39         case 'PST':
  40             $tzc = '-0800';
  41             break;
  42         case 'Mountain':
  43         case 'MST':
  44         case 'PDT':
  45             $tzc = '-0700';
  46             break;
  47         case 'Central':
  48         case 'CST':
  49         case 'MDT':
  50             $tzc = '-0600';
  51             break;
  52         case 'Eastern':
  53         case 'EST':
  54         case 'CDT':
  55             $tzc = '-0500';
  56             break;
  57         case 'EDT':
  58             $tzc = '-0400';
  59             break;
  60         case 'GMT':
  61             $tzc = '+0000';
  62             break;
  63         case 'BST':
  64         case 'MET':
  65         case 'CET':
  66             $tzc = '+0100';
  67             break;
  68         case 'EET':
  69         case 'IST':
  70         case 'MET DST':
  71         case 'METDST':
  72         case 'MEST':
  73         case 'CEST':
  74             $tzc = '+0200';
  75             break;
  76         case 'HKT':
  77             $tzc = '+0800';
  78             break;
  79         case 'JST':
  80         case 'KST':
  81             $tzc = '+0900';
  82             break;
  83     }
  84     $neg = false;
  85     if (substr($tzc, 0, 1) == '-') {
  86         $neg = true;
  87     } else if (substr($tzc, 0, 1) != '+') {
  88         $tzc = '+'.$tzc;
  89     }
  90     $hh = substr($tzc,1,2);
  91     $mm = substr($tzc,3,2);
  92     $iTzc = ($hh * 60 + $mm) * 60;
  93     if ($neg) $iTzc = -1 * (int) $iTzc;
  94     /* stamp in gmt */
  95     $stamp -= $iTzc;
  96     /* now find what the server is at */
  97     $current = date('Z', time());
  98     /* stamp in local timezone */
  99     $stamp += $current;
 100
 101     return $stamp;
 102 }
 103
 104 /**
 105  * Returns the (localized) string for a given day number.
 106  * Switch system has been intentionaly chosen for the
 107  * internationalization of month and day names. The reason
 108  * is to make sure that _("") strings will go into the
 109  * main po.
 110  *
 111  * @param int day_number the day number
 112  * @return string the day in human readable form
 113  */
 114 function getDayName( $day_number ) {
 115
 116     switch( $day_number ) {
 117     case 0:
 118         $ret = _("Sunday");
 119         break;
 120     case 1:
 121         $ret = _("Monday");
 122         break;
 123     case 2:
 124         $ret = _("Tuesday");
 125         break;
 126     case 3:
 127         $ret = _("Wednesday");
 128         break;
 129     case 4:
 130         $ret = _("Thursday");
 131         break;
 132     case 5:
 133         $ret = _("Friday");
 134         break;
 135     case 6:
 136         $ret = _("Saturday");
 137         break;
 138     default:
 139         $ret = '';
 140     }
 141     return( $ret );
 142 }
 143
 144 /**
 145  * Like getDayName, but returns the short form
 146  * @param int day_number the day number
 147  * @return string the day in short human readable form
 148  */
 149 function getDayAbrv( $day_number ) {
 150
 151     switch( $day_number ) {
 152     case 0:
 153         $ret = _("Sun");
 154         break;
 155     case 1:
 156         $ret = _("Mon");
 157         break;
 158     case 2:
 159         $ret = _("Tue");
 160         break;
 161     case 3:
 162         $ret = _("Wed");
 163         break;
 164     case 4:
 165         $ret = _("Thu");
 166         break;
 167     case 5:
 168         $ret = _("Fri");
 169         break;
 170     case 6:
 171         $ret = _("Sat");
 172         break;
 173     default:
 174         $ret = '';
 175     }
 176     return( $ret );
 177 }
 178
 179
 180 /**
 181  * Returns the (localized) string for a given month number.
 182  *
 183  * @param string month_number the month number (01..12)
 184  * @return string the month name in human readable form
 185  */
 186 function getMonthName( $month_number ) {
 187     switch( $month_number ) {
 188      case '01':
 189         $ret = _("January");
 190         break;
 191      case '02':
 192         $ret = _("February");
 193         break;
 194      case '03':
 195         $ret = _("March");
 196         break;
 197      case '04':
 198         $ret = _("April");
 199         break;
 200      case '05':
 201         $ret = _("May");
 202         break;
 203      case '06':
 204         $ret = _("June");
 205         break;
 206      case '07':
 207         $ret = _("July");
 208         break;
 209      case '08':
 210         $ret = _("August");
 211         break;
 212      case '09':
 213         $ret = _("September");
 214         break;
 215      case '10':
 216         $ret = _("October");
 217         break;
 218      case '11':
 219         $ret = _("November");
 220         break;
 221      case '12':
 222         $ret = _("December");
 223         break;
 224      default:
 225         $ret = '';
 226     }
 227     return( $ret );
 228 }
 229
 230 /**
 231  * Returns the (localized) string for a given month number,
 232  * short representation.
 233  *
 234  * @param string month_number the month number (01..12)
 235  * @return string the shortened month in human readable form
 236  */
 237 function getMonthAbrv( $month_number ) {
 238     switch( $month_number ) {
 239      case '01':
 240         $ret = _("Jan");
 241         break;
 242      case '02':
 243         $ret = _("Feb");
 244         break;
 245      case '03':
 246         $ret = _("Mar");
 247         break;
 248      case '04':
 249         $ret = _("Apr");
 250         break;
 251      case '05':
 252         $ret = _("Ma&#121;");
 253         break;
 254      case '06':
 255         $ret = _("Jun");
 256         break;
 257      case '07':
 258         $ret = _("Jul");
 259         break;
 260      case '08':
 261         $ret = _("Aug");
 262         break;
 263      case '09':
 264         $ret = _("Sep");
 265         break;
 266      case '10':
 267         $ret = _("Oct");
 268         break;
 269      case '11':
 270         $ret = _("Nov");
 271         break;
 272      case '12':
 273         $ret = _("Dec");
 274         break;
 275      default:
 276         $ret = '';
 277     }
 278     return( $ret );
 279 }
 280
 281 /**
 282  * Returns the localized representation of the date/time.
 283  *
 284  * @param string date_format The format for the date, like the input for the PHP date() function.
 285  * @param int stamp the timestamp to convert
 286  * @return string a full date representation
 287  */
 288 function date_intl( $date_format, $stamp ) {
 289     $ret = str_replace( array('D','F','l','M'), array('$1','$2','$3','$4'), $date_format );
 290     // to reduce the date calls we retrieve m and w in the same call
 291     $ret = date('w#m#'. $ret, $stamp );
 292     // extract day and month in order to replace later by intl day and month
 293     $aParts = explode('#',$ret);
 294     $ret = str_replace(array('$1','$4','$2','$3',), array(getDayAbrv($aParts[0]),
 295                                                           getMonthAbrv($aParts[1]),
 296                                                           getMonthName($aParts[1]),
 297                                                           getDayName($aParts[0])),
 298                                                           $aParts[2]);
 299     return( $ret );
 300 }
 301
 302 /**
 303  * This returns a date of the format "Wed, Oct 29, 2003 9:52 am",
 304  * or the same in 24H format (depending on the user's settings),
 305  * and taking localization into accout.
 306  *
 307  * @param int stamp the timestamp
 308  * @return string the long date string
 309  */
 310 function getLongDateString( $stamp ) {
 311
 312     global $hour_format;
 313
 314     if ($stamp == -1) {
 315         return '';
 316     }
 317
 318     if ( $hour_format == SMPREF_TIME_12HR ) {
 319         $date_format = _("D, F j, Y g:i a");
 320     } else {
 321         $date_format = _("D, F j, Y H:i");
 322     }
 323
 324     return( date_intl( $date_format, $stamp ) );
 325
 326 }
 327
 328 /**
 329  * Returns a short representation of the date,
 330  * taking timezones and localization into account.
 331  * Depending on user's settings, this string can be
 332  * of the form: "14:23" or "Jun 14, 2003" depending
 333  * on whether the stamp is "today" or not.
 334  *
 335  * @param int stamp the timestamp
 336  * @return string the date string
 337  */
 338 function getDateString( $stamp ) {
 339
 340     global $invert_time, $hour_format, $show_full_date;
 341
 342     if ( $stamp == -1 ) {
 343        return '';
 344     }
 345
 346     $now = time();
 347
 348     $dateZ = date('Z', $now );
 349
 350     // FIXME: isn't this obsolete and introduced as a terrible workaround
 351     // for bugs at other places which are fixed a long time ago?
 352     if ($invert_time) {
 353         $dateZ = - $dateZ;
 354     }
 355
 356     // calculate when it was midnight and when it will be,
 357     // in order to display dates differently if they're 'today'
 358     $midnight = $now - ($now % 86400) - $dateZ;
 359     // this is to correct if after calculations midnight is more than
 360     // one whole day away.
 361     if ($now - $midnight > 86400) {
 362         $midnight += 86400;
 363     }
 364     $nextmid = $midnight + 86400;
 365
 366     if (($show_full_date == 1) || ($nextmid < $stamp)) {
 367         $date_format = _("M j, Y");
 368     } else if ($midnight < $stamp) {
 369         /* Today */
 370         if ( $hour_format == SMPREF_TIME_12HR ) {
 371             $date_format = _("g:i a");
 372         } else {
 373             $date_format = _("H:i");
 374         }
 375     } else if ($midnight - 518400 < $stamp) {
 376         /* This week */
 377         if ( $hour_format == SMPREF_TIME_12HR ) {
 378             $date_format = _("D, g:i a");
 379         } else {
 380             $date_format = _("D, H:i");
 381         }
 382     } else {
 383         /* before this week */
 384         $date_format = _("M j, Y");
 385     }
 386
 387     return( date_intl( $date_format, $stamp ) );
 388 }
 389
 390 /**
 391  * Decodes a RFC 822 Date-header into a timestamp
 392  *
 393  * @param array dateParts the Date-header split by whitespace
 394  * @return int the timestamp calculated from the header
 395  */
 396 function getTimeStamp($dateParts) {
 397     /* $dateParts[0] == <day of week>   Mon, Tue, Wed
 398      * $dateParts[1] == <day of month>  23
 399      * $dateParts[2] == <month>         Jan, Feb, Mar
 400      * $dateParts[3] == <year>          1999
 401      * $dateParts[4] == <time>          18:54:23 (HH:MM:SS)
 402      * $dateParts[5] == <from GMT>      +0100
 403      * $dateParts[6] == <zone>          (EDT)
 404      *
 405      * NOTE:  In RFC 822, it states that <day of week> is optional.
 406      *        In that case, dateParts[0] would be the <day of month>
 407      *        and everything would be bumped up one.
 408      */
 409
 410     /*
 411      * Simply check to see if the first element in the dateParts
 412      * array is an integer or not.
 413      * Since the day of week is optional, this check is needed.
 414      */
 415      if (count($dateParts) <2) {
 416         return -1;
 417      } else if (count($dateParts) ==3) {
 418         if (substr_count($dateParts[0],'-') == 2 &&
 419             substr_count($dateParts[1],':') == 2) {
 420             //  dd-Month-yyyy 23:19:05 +0200
 421             //  redefine the date
 422             $aDate = explode('-',$dateParts[0]);
 423             $newDate = array($aDate[0],$aDate[1],$aDate[2],$dateParts[1],$dateParts[2]);
 424             $dateParts = $newDate;
 425         }
 426      }
 427
 428     /* remove day of week */
 429     if (!is_numeric(trim($dateParts[0]))) {
 430         $dataParts = array_shift($dateParts);
 431     }
 432     /* calculate timestamp separated from the zone and obs-zone */
 433     $stamp = strtotime(implode (' ', array_splice ($dateParts,0,4)));
 434     if (!isset($dateParts[0])) {
 435         $dateParts[0] = '+0000';
 436     }
 437
 438     if (!preg_match('/^[+-]{1}[0-9]{4}$/',$dateParts[0])) {
 439         /* zone in obs-zone format */
 440         if (preg_match('/\((.+)\)/',$dateParts[0],$regs)) {
 441             $obs_zone = $regs[1];
 442         } else {
 443             $obs_zone = $dateParts[0];
 444         }
 445         return getGMTSeconds($stamp, $obs_zone);
 446     } else {
 447         return getGMTSeconds($stamp, $dateParts[0]);
 448     }
 449 }