Typed array

PageUnitsCollection.php

<?php
/** Collection handler for webpage content blocks
*
* @version SVN: $Id: PageUnitsCollection.php 1231 2018-08-11 19:40:50Z anrdaemon $
*/

namespace AnrDaemon\CcWeb\Helpers;

use
  AnrDaemon\CcWeb\Objects\PageUnit;

class PageUnitsCollection
extends \ArrayObject
{
  public function _sort(PageUnit $a, PageUnit $b)
  {
    if($a['showorder'] > $b['showorder'])
      return 1;

    if($a['showorder'] < $b['showorder'])
      return -1;

    if($a['id'] > $b['id'])
      return 1;

    if($a['id'] < $b['id'])
      return -1;

    return 0;
  }

  protected function _validate($state, $index = null)
  {
    if(is_null($state))
      return null;

    if($state instanceof PageUnit)
      return $state;

    if(is_array($state))
    {
      $value = PageUnit::createFromState($value);
      return $value;
    }

    throw new \InvalidArgumentException("Value " . ($index ? "at index {$index} " : "") . "must be of type AnrDaemon\\CcWeb\\Objects\\PageUnit or compatible.");
  }

// Magic!

  public function __construct($array = array(), $flags = 0)
  {
    parent::{__FUNCTION__}([], $flags);
    $this->exchangeArray($array);
  }

// ArrayAccess

  public function offsetSet($offset, $state)
  {
    $value = $this->_validate($state);

    if(empty($value))
      return $this->offsetUnset($offset);

    return parent::{__FUNCTION__}($offset, $value);
  }

// ArrayObject

  public function append($value)
  {
    return $this->offsetSet(null, $value);
  }

  public function asort()
  {
    $this->uasort([$this, "_sort"]);
  }

  public function exchangeArray($array)
  {
    $data = [];
    foreach($array as $offset => $state)
    {
      $value = $this->_validate($state, $offset);

      if(empty($value))
        continue;

      $data[$offset] = $value;
    }

    return parent::{__FUNCTION__}($data);
  }

// Serializable

  public function serialize()
  {
    return serialize($this->getArrayCopy());
  }

  public function unserialize($value)
  {
    $this->exchangeArray(unserialize($value));
  }
}