<?php
class linkChecker
{
    protected $_links = array();
 
    protected $_sites = array();
 
 
    public function __construct() 
    {
 
    }
 
    public function addSite($site)
    {
        if (in_array($site, $this->_sites)) {
            throw new linkException("Site already in list");
        }
 
        $this->_sites[] = $site;
    }
 
    public function processSites()
    {
        foreach ($this->_sites as $site) {
            $this->_processLinks($site);
        }
    }
 
    protected function _processLinks($url)
    {
        $this->_addLink($url, $url);
        $d = new DomDocument;
        @$d->loadHTMLFile($url);
        foreach ($d->getElementsByTagName('a') as $link) {
            $this->_addLink($link->getAttribute('href'), $url);
        }
        unset($d);
    }
 
    protected function _addLink($link, $url)
    {
        $l = new checkableLink($link, $url);
        if (!isset($this->_links[$l->url])) {
            $this->_checkLink($l);
            $this->_links[$l->url] = $l;
        }
        unset($l);
    }
 
    protected function _checkLink(checkableLink &amp;$checkableLink)
    {
        $d = new DomDocument;
        $d->loadHTMLFile($checkableLink->url) or $checkableLink->valid = false;
    }
}
 
 
 
 
 
 
class checkableLink
{
    public $host = null;
 
    public $url = null;
 
    public $checked = false;
 
    public $valid = true;
 
    public function __construct($link = null, $url = null)
    {
        if (stripos($link, '/') === 0) {
            $this->url = $url . $link;
        }
        else {
            $this->url = $url;
        }
    }
}
 
class linkException extends exception
{}
?>