timeago.inc.php

<?php

function timeAgoInWords($timestring, $timezone = NULL) {
  $timeAgo = new TimeAgo($timezone);
  
  return $timeAgo->inWords($timestring, "now");
}

/** 
 * This class can help you find out just how much time has passed between
 * two dates.
 *
 * It has two functions you can call:
 * inWords() which gives you the "time ago in words" between two dates.
 * dateDifference() which returns an array of years,months,days,hours,minutes and
 * seconds between the two dates.
 *
 * @author jimmiw
 * @since 0.2.0 (2010/05/05)
 * @site http://github.com/jimmiw/php-time-ago
 */
class TimeAgo {
  // defines the number of seconds per "unit"
  private $secondsPerMinute;
  private $secondsPerHour;
  private $secondsPerDay;
  private $secondsPerMonth;
  private $secondsPerYear;
  private $timezone;
  
  public function __construct($timezone = NULL) {
    $this->secondsPerMinute = 60;
    $this->secondsPerHour = $this->secondsPerMinute * 60;
    $this->secondsPerDay = $this->secondsPerHour * 24;
    $this->secondsPerMonth = $this->secondsPerDay * 30;
    $this->secondsPerYear = $this->secondsPerMonth * 12;
    
    // if the $timezone is null, we take 'Europe/London' as the default
    // this was done, because the parent construct tossed an exception
    if($timezone == NULL) {
      $timezone = 'Europe/Copenhagen';
    }
    
    $this->timezone = $timezone;
  }
  
  public function inWords($past, $now = "now") {
    // sets the default timezone
    date_default_timezone_set($this->timezone);
    // finds the past in datetime
    $past = strtotime($past);
    // finds the current datetime
    $now = strtotime($now);
    
    // creates the "time ago" string. This always starts with an "about..."
    $timeAgo = "";
    
    // finds the time difference
    $timeDifference = $now - $past;
    
    // less than 29secs
    if($timeDifference <= 29) {
      $timeAgo = "less than a minute";
    }
    // more than 29secs and less than 1min29secss
    else if($timeDifference > 29 && $timeDifference <= 89) {
      $timeAgo = "1 minute";
    }
    // between 1min30secs and 44mins29secs
    else if($timeDifference > 89 &&
      $timeDifference <= (($this->secondsPerMinute * 44) + 29)
    ) {
      $minutes = floor($timeDifference / $this->secondsPerMinute);
      $timeAgo = $minutes." minutes";
    }
    // between 44mins30secs and 1hour29mins29secs
    else if(
      $timeDifference > (($this->secondsPerMinute * 44) + 29)
      &&
      $timeDifference < (($this->secondsPerMinute * 89) + 29)
    ) {
      $timeAgo = "about 1 hour";
    }
    // between 1hour29mins30secs and 23hours59mins29secs
    else if(
      $timeDifference > (
        ($this->secondsPerMinute * 89) +
        29
      )
      &&
      $timeDifference <= (
        ($this->secondsPerHour * 23) +
        ($this->secondsPerMinute * 59) +
        29
      )
    ) {
      $hours = floor($timeDifference / $this->secondsPerHour);
      $timeAgo = $hours." hours";
    }
    // between 23hours59mins30secs and 47hours59mins29secs
    else if(
      $timeDifference > (
        ($this->secondsPerHour * 23) +
        ($this->secondsPerMinute * 59) +
        29
      )
      &&
      $timeDifference <= (
        ($this->secondsPerHour * 47) +
        ($this->secondsPerMinute * 59) +
        29
      )
    ) {
      $timeAgo = "1 day";
    }
    // between 47hours59mins30secs and 29days23hours59mins29secs
    else if(
      $timeDifference > (
        ($this->secondsPerHour * 47) +
        ($this->secondsPerMinute * 59) +
        29
      )
      &&
      $timeDifference <= (
        ($this->secondsPerDay * 29) +
        ($this->secondsPerHour * 23) +
        ($this->secondsPerMinute * 59) +
        29
      )
    ) {
      $days = floor($timeDifference / $this->secondsPerDay);
      $timeAgo = $days." days";
    }
    // between 29days23hours59mins30secs and 59days23hours59mins29secs
    else if(
      $timeDifference > (
        ($this->secondsPerDay * 29) +
        ($this->secondsPerHour * 23) +
        ($this->secondsPerMinute * 59) +
        29
      )
      &&
      $timeDifference <= (
        ($this->secondsPerDay * 59) +
        ($this->secondsPerHour * 23) +
        ($this->secondsPerMinute * 59) +
        29
      )
    ) {
      $timeAgo = "about 1 month";
    }
    // between 59days23hours59mins30secs and 1year (minus 1sec)
    else if(
      $timeDifference > (
        ($this->secondsPerDay * 59) + 
        ($this->secondsPerHour * 23) +
        ($this->secondsPerMinute * 59) +
        29
      )
      &&
      $timeDifference < $this->secondsPerYear
    ) {
      $months = round($timeDifference / $this->secondsPerMonth);
      // if months is 1, then set it to 2, because we are "past" 1 month
      if($months == 1) {
        $months = 2;
      }
      
      $timeAgo = $months." months";
    }
    // between 1year and 2years (minus 1sec)
    else if(
      $timeDifference >= $this->secondsPerYear
      &&
      $timeDifference < ($this->secondsPerYear * 2)
    ) {
      $timeAgo = "about 1 year";
    }
    // 2years or more
    else {
      $years = floor($timeDifference / $this->secondsPerYear);
      $timeAgo = "over ".$years." years";
    }
    
    return $timeAgo;
  }
  
  public function dateDifference($past, $now = "now") {
    // initializes the placeholders for the different "times"
    $seconds = 0;
    $minutes = 0;
    $hours = 0;
    $days = 0;
    $months = 0;
    $years = 0;
    
    // sets the default timezone
    date_default_timezone_set($this->timezone);
    
    // finds the past in datetime
    $past = strtotime($past);
    // finds the current datetime
    $now = strtotime($now);
    
    // calculates the difference
    $timeDifference = $now - $past;
    
    // starts determining the time difference
    if($timeDifference >= 0) {
      switch($timeDifference) {
        // finds the number of years
        case ($timeDifference >= $this->secondsPerYear):
          // uses floor to remove decimals
          $years = floor($timeDifference / $this->secondsPerYear);
          // saves the amount of seconds left
          $timeDifference = $timeDifference-($years * $this->secondsPerYear);
        
        // finds the number of months
        case ($timeDifference >= $this->secondsPerMonth && $timeDifference <= ($this->secondsPerYear-1)):
          // uses floor to remove decimals
          $months = floor($timeDifference / $this->secondsPerMonth);
          // saves the amount of seconds left
          $timeDifference = $timeDifference-($months * $this->secondsPerMonth);
        
        // finds the number of days
        case ($timeDifference >= $this->secondsPerDay && $timeDifference <= ($this->secondsPerYear-1)):
          // uses floor to remove decimals
          $days = floor($timeDifference / $this->secondsPerDay);
          // saves the amount of seconds left
          $timeDifference = $timeDifference-($days * $this->secondsPerDay);
        
        // finds the number of hours
        case ($timeDifference >= $this->secondsPerHour && $timeDifference <= ($this->secondsPerDay-1)):
          // uses floor to remove decimals
          $hours = floor($timeDifference / $this->secondsPerHour);
          // saves the amount of seconds left
          $timeDifference = $timeDifference-($hours * $this->secondsPerHour);
        
        // finds the number of minutes
        case ($timeDifference >= $this->secondsPerMinute && $timeDifference <= ($this->secondsPerHour-1)):
          // uses floor to remove decimals
          $minutes = floor($timeDifference / $this->secondsPerMinute);
          // saves the amount of seconds left
          $timeDifference = $timeDifference-($minutes * $this->secondsPerMinute);
          
        // finds the number of seconds
        case ($timeDifference <= ($this->secondsPerMinute-1)):
          // seconds is just what there is in the timeDifference variable
          $seconds = $timeDifference;
      }
    }
    
    $difference = array(
      "years" => $years,
      "months" => $months,
      "days" => $days,
      "hours" => $hours,
      "minutes" => $minutes,
      "seconds" => $seconds
    );
    
    return $difference;
  }
}

?>