<?php
/* Author: Peter Nelson / @_peterdn - controllers\url.php
 * The main controller for the site. */
 
	class Url extends Controller
	{
		public function Url()
		{
			parent::Controller();
			$this->load->helper("url");
		}
		
		public function index()
		{
			$this->load->view("url_create");
		}
				
		public function redirect()
		{
			$subs = explode("/", uri_string());
			$slug = $subs[3];
			
			$this->load->model("Urls_table");
			$url = $this->Urls_table->getUrlForSlug($slug);
			$this->Urls_table->incrementHits($slug);
			
			if ($url)
			{
				// Redirect to url or to a warning page,
				// depending on the urls perceived reputation.
				// Give the site the benefit of the doubt if we
				// can get no information about it.
				$rep = $this->_getUrlReputation($url);
				if ($rep && is_array($rep))
				{
					$min = 100;
					foreach ($rep as $name => $r)
						$min = $min < $r["reputation"] ? $min : $r["reputation"];
						
					if ($min < 60)
						redirect("/url/warning/$slug");
				}
				
				header("location: $url");
				exit();
			}
			else
			{
				redirect("/");
			}
		}
		
		public function warning()
		{			
			$subs = explode("/", uri_string());
			$slug = $subs[3];
			
			$this->load->model("Urls_table");
			$url = $this->Urls_table->getUrlForSlug($slug);
			
			if ($url)
			{
				$rep = $this->_getUrlReputation($url);
				$hostname = parse_url($url, PHP_URL_HOST);
				
				$data = Array("slug" => $slug, "url" => $url, 
				  "rep" => $rep, "hostname" => $hostname);
				$this->load->view("url_warning", $data);
			}
			else
			{
				redirect("/");
			}
		}
		
		public function create()
		{
			$url = $this->input->post("url");
			$url = filter_var($url, FILTER_VALIDATE_URL, FILTER_FLAG_SCHEME_REQUIRED);
			
			if (!$url)
				redirect("/");
			
			$this->load->model("Urls_table");
			
			$n = 5;
			$i = 0;
			do
			{
				$slug = $this->Urls_table->generateSlug($n);
				if ($n < 10 && ++$i % 5 == 0)
					++$n;
			}
			while ($this->Urls_table->doesSlugExist($slug));

			$date = new DateTime();
			$date = $date->format("Y-m-d H:i:s");
			
			$slug = $this->Urls_table->createUrlRow($url, $slug, $date, 0, 0);
						
			redirect("/url/view/$slug");
		}
		
		public function view()
		{
			$slug = $this->uri->segment(3);
			$this->load->model("Urls_table");
			if ($url = $this->Urls_table->getUrlForSlug($slug))
			{
				$rep = $this->_getUrlReputation($url);
				$hostname = parse_url($url, PHP_URL_HOST);
				$hits = $this->Urls_table->getHitsForSlug($slug);
				
				$data = Array("slug" => $slug, "url" => $url, 
				  "rep" => $rep, "hostname" => $hostname, "hits" => $hits);
				$this->load->view("url_view", $data);
			}
			else
			{
				redirect("/");
			}
		}
		
		public function privacy()
		{
			$this->load->view("url_privacy");
		}
		
		private function _getUrlReputation($url)
		{
			// URL reputation data provided by WOT
			// More info at http://www.mywot.com/wiki/API
			$attributes = array(0 => "Trustworthiness", 1 => "Vendor reliability",
			  2 => "Privacy", 4 => "Child safety");
			
			$r = new HttpRequest("http://api.mywot.com/0.4/public_query2",
			  HttpRequest::METH_GET);
			$r->setOptions(array("timeout" => 3));
			$r->addQueryData(array("url" => $url));
			try
			{
				$r->send();
				if ($r->getResponseCode() == 200)
				{
					// parse the XML response
					$doc = new DOMDocument();
					$doc->loadXML($r->getResponseBody());
					$qs = $doc->getElementsByTagName("query");
					if (!$qs || $qs->length < 1)
						return false;
					
					$q = $qs->item(0);
					$apps = $q->getElementsByTagName("application");
					if (!$apps)
						return false;
					
					$reps = array();
					$min = 100;
					for ($i = 0; $i < $apps->length; ++$i)
					{
						$a = $apps->item($i);
						$name = (int)$a->attributes->getNamedItem("name")->nodeValue;
						$rep = (int)$a->attributes->getNamedItem("r")->nodeValue;
						$min = $min < $rep ? $min : $rep;
						$conf = (int)$a->attributes->getNamedItem("c")->nodeValue;
						$reps[$attributes[$name]] = array("reputation" => $rep, "confidence" => $conf);
					}
					return $reps;
				}
			}
			catch (HttpException $ex)
			{
				return false;
			}
		}
	}