<?php
/**
* SeekQuarry/Yioop --
* Open Source Pure PHP Search Engine, Crawler, and Indexer
*
* Copyright (C) 2009, 2010, 2011 Chris Pollett hide@address.com
*
* LICENSE:
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* END LICENSE
*
* @author Chris Pollett hide@address.com
* @package seek_quarry
* @subpackage processor
* @license http://www.gnu.org/licenses/ GPL3
* @link http://www.seekquarry.com/
* @copyright 2009, 2010, 2011
* @filesource
*/
if(!defined('BASE_DIR')) {echo "BAD REQUEST"; exit();}
/**
* Load base class, if needed.
*/
require_once BASE_DIR."/lib/processors/text_processor.php";
/**
* Load so can parse urls
*/
require_once BASE_DIR."/lib/url_parser.php";
/**
* Used for convertPixels
*/
require_once BASE_DIR."/lib/utility.php";
/**
* Used to create crawl summary information
* for SVG files. This class is a little bit
* weird in that it generates thumbs like the
* image processor classes, but when it gives
* up on the data it falls back to text
* processor handling.
*
* @author Chris Pollett
* @package seek_quarry
* @subpackage processor
*/
class SvgProcessor extends TextProcessor
{
const MAX_DESCRIPTION_LEN = 2000;
const MAX_THUMB_LEN = 5000;
/**
* Used to extract the title, description and links from
* a string consisting of svg image. If the image is small
* enough, an attempt is made to generate a thumbnail
*
* @param string $page web-page contents
* @param string $url the url where the page contents came from,
* used to canonicalize relative links
*
* @return array a summary of the contents of the page
*
*/
public function process($page, $url)
{
if(is_string($page)) {
self::closeDanglingTags($page);
$dom = self::dom($page);
if($dom !== false && isset($dom->documentElement)) {
$summary[self::TITLE] = "";
$summary[self::DESCRIPTION] = self::description($dom);
$summary[self::LINKS] = array();
$summary[self::PAGE] =
"<html><body><div><img src='data:image/svg+xml;base64," .
base64_encode($page)."' alt='".$summary[self::DESCRIPTION].
"' /></div></body></html>";
if(strlen($page) < self::MAX_THUMB_LEN) {
$thumb_string = self::createThumb($dom);
$summary[self::THUMB] = 'data:image/svg+xml;base64,'.
base64_encode($thumb_string);
}
}else {
$summary = parent::process($page, $url);
}
}
return $summary;
}
/**
* Used to create an svg thumbnail from a dom object
*
* @param object $dom a dom svg image object
*
*/
static function createThumb($dom)
{
$svg = $dom->documentElement;
if($svg->hasAttribute("width")) {
$width = $svg->getAttribute("width");
} else {
$width = 600;
}
$width = convertPixels($width);
if($svg->hasAttribute("height")) {
$height = $svg->getAttribute("height");
} else {
$height = 600;
}
$height = convertPixels($height);
$svg->setAttributeNS("", "width", "150px");
$svg->setAttributeNS("", "height", "150px");
if(!$svg->hasAttribute("viewBox")) {
$svg->setAttributeNS("", "viewBox", "0 0 $width $height");
}
return $dom->saveXML();
}
/**
* Return a document object based on a string containing the contents of
* an SVG page
*
* @param string $page a web page
*
* @return object document object
*/
static function dom($page)
{
$dom = new DOMDocument();
@$dom->loadXML($page);
return $dom;
}
/**
* Returns html head title of a webpage based on its document object
*
* @param object $dom a document object to extract a title from.
* @return string a title of the page
*
*/
static function title($dom)
{
$sites = array();
$xpath = new DOMXPath($dom);
$titles = $xpath->evaluate("/svg//desc");
$title = "";
foreach($titles as $pre_title) {
$title .= $pre_title->textContent;
}
return $title;
}
/**
* Returns descriptive text concerning a svg page based on its document
* object
*
* @param object $dom a document object to extract a description from.
* @return string a description of the page
*/
static function description($dom) {
$sites = array();
$xpath = new DOMXPath($dom);
$description = "";
/*
concatenate the contents of then additional dom elements up to
the limit of description length
*/
$page_parts = array("/svg//desc",
"/svg//text");
foreach($page_parts as $part) {
$doc_nodes = $xpath->evaluate($part);
foreach($doc_nodes as $node) {
$description .= " ".$node->textContent;
if(strlen($description) > self::MAX_DESCRIPTION_LEN) { break 2;}
}
}
$description = mb_ereg_replace("(\s)+", " ", $description);
return $description;
}
}
?>