<?php
/**
* @brief Union Iterator Pattern
* @author <a href='https://www.invisioncommunity.com'>Invision Power Services, Inc.</a>
* @copyright (c) Invision Power Services, Inc.
* @license https://www.invisioncommunity.com/legal/standards/
* @package Invision Community
* @since 14 Nov 2014
*/
namespace IPS\Patterns;
/* To prevent PHP errors (extending class does not exist) revealing path */
if ( !defined( '\IPS\SUITE_UNIQUE_KEY' ) )
{
header( ( isset( $_SERVER['SERVER_PROTOCOL'] ) ? $_SERVER['SERVER_PROTOCOL'] : 'HTTP/1.0' ) . ' 403 Forbidden' );
exit;
}
/**
* Union Iterator Pattern
*/
class _UnionIterator implements \Iterator, \Countable
{
/**
* @brief Iterators
*/
protected $iterators;
/**
* @brief Current lowest value
*/
protected $currentIteratorKey;
/**
* @brief Order Direction
*/
protected $orderDirection;
/**
* Constructor
*
* @param string $orderDirection "asc" or "desc"
* @return void
*/
public function __construct( $orderDirection )
{
$this->iterators = new \SplObjectStorage;
$this->orderDirection = $orderDirection;
}
/**
* Attach Iterator
*
* @param \Traverable $iterator Iterator
* @param mixed $key The name of the property which contains the value used to compare positions
* @return void
*/
public function attachIterator( \Traversable $iterator, $key )
{
$this->iterators->attach( $iterator, $key );
}
/**
* Rewind
*
* @return void
*/
public function rewind()
{
foreach ( $this->iterators as $iterator )
{
$iterator->rewind();
}
$this->currentLowestValue = NULL;
$this->next();
}
/**
* Get current row
*
* @return array
*/
public function current()
{
foreach ( $this->iterators as $k => $iterator )
{
if ( $k === $this->currentIteratorKey )
{
$return = $iterator->current();
$iterator->next();
return $return;
}
}
}
/**
* Get current key
*
* @return mixed
*/
public function key()
{
return NULL;
}
/**
* Fetch next result
*
* @return void
*/
public function next()
{
$this->currentIteratorKey = NULL;
$currentLowestValue = NULL;
$values = array();
foreach ( $this->iterators as $k => $iterator )
{
if ( $iterator->valid() )
{
$col = $this->iterators->getInfo();
$current = $iterator->current();
if ( is_array( $current ) )
{
$value = $current[ $col ];
}
else
{
$value = $current->$col;
}
if ( $value instanceof \IPS\DateTime )
{
$value = $value->getTimestamp();
}
if ( $currentLowestValue === NULL or ( $this->orderDirection === 'asc' and $value < $currentLowestValue ) or ( $this->orderDirection === 'desc' and $value > $currentLowestValue ) )
{
$currentLowestValue = $value;
$this->currentIteratorKey = $k;
}
}
}
}
/**
* Is the current row valid?
*
* @return bool
*/
public function valid()
{
return $this->currentIteratorKey !== NULL;
}
/**
* Get count
*
* @return void
*/
public function count()
{
$count = 0;
foreach ( $this->iterators as $iterator )
{
$count += count( $iterator );
}
return $count;
}
}