<?php
define("HISTORY_OVERWRITE",1);
define("HISTORY_PREFERENCES",2);
define("HISTORY_OVERWRITEINARRAY",4);

class History {
  public $id = '';
  private $history = array();
  private $options = array();
  private $final = array();
  private $preferences = array();

  public function __construct($id,$opt=array(),$pref=array()) {
    $this->id = $id;
    $this->setOptions($opt);
    $this->setPreferences($pref);
  }

  public function add($hist,$removeDuplicates=false) {
    if($removeDuplicates) {
      if($this->history[count($this->history)-1] != $this) {
        $this->history[] = $hist;
      }
    } else $this->history[] = $hist;

    $this->_mergeElement($hist);

    return $this->final;
  }

  public function setOptions($opt) {
    $this->options = $opt;

    return true;
  }

  public function setPreferences($pref) {
    $this->preferences = $pref;

    return true;
  }

  public function setHistory($hist) {
    $this->history = $hist;

    return true;
  }

  public function merge() {
    foreach($this->history as $hist) {
      $this->_mergeElement($hist);
    }

    return $this->final;
  }

  private function _mergeElement($hist) {
    foreach($hist as $key=>$elem) {
      if($this->_checkPermission($key,HISTORY_OVERWRITE)) {
        if(array_key_exists($key,$this->final)) {
          $this->final[$key] = ($this->_checkPermission($key,HISTORY_PREFERENCES)) ? $this->_checkPreferences($key,$elem,$this->final[$key]) : $elem;
        } else $this->final[$key] = $elem;
      } else $this->final[$key][] = $elem;
    }
  }

  private function _checkPermission($key,$option) {
    if(!array_key_exists($key,$this->options)) return false;
    return ($option & $this->options[$key]) ? true : false;
  }

  private function _checkPreferences($key,$e1,$e2) {
    if(array_key_exists($key,$this->preferences)) {
      foreach($this->preferences[$key] as $e) {
        if($e1 == $e or $e2 == $e) return $e;
      }
    } else return $e1;
  }
}

$o = new History("t");
$o->setOptions(array(
  'status' => HISTORY_OVERWRITE | HISTORY_PREFERENCES,
  'dsn' => HISTORY_OVERWRITE,
  'delays' => HISTORY_OVERWRITE,
  'delay' => HISTORY_OVERWRITE,
  'to' => HISTORY_OVERWRITE,
  'relay' => HISTORY_OVERWRITE,
  'id' => HISTORY_OVERWRITE
));

$o->setPreferences(array(
  'status' => array('sent','deferred')
));

$arr = $o->add(array(
    "status" => "sent"
    , "dsn" => "2.0.0"
    , "relay" => "mailin-03.mx.aol.com[205.188.59.193] =>25"
    , "delays" => "0.52/0/0.64/1.6"
    , "delay" => "2.7"
    , "to" => "testsetes"
    , "id" => "0039560E4"
));
print_r($arr);
$arr = $o->add(array(
    "status" => "deferred"
    , "dsn" => "2.0.0"
    , "relay" => "mailin-03.mx.aol.com[205.188.59.193] =>25"
    , "delays" => "0.52/0/0.64/1.6"
    , "delay" => "2.7"
    , "to" => "something else"
    , "id" => "0039560E4"
));
?>