<?php
/**
 * SEF advanced component extension
 *
 * !! Must Be Named sef_ext.gallery.php !!
 *
 * This file is to be used with Mambo, Xaneon extensions, and the Gallery projects to
 * produce Search Engine Friendly URL's. To work, this extension file must be placed
 * in administrator/components/com_sef/extensions and my gallery patch must be used
 * so gallery will respect the Mambo SEF flag. The gallery patch is located
 * here: http://www.thegillis.net/examples/mambo/gallery.mambo.sef.patch
 * The extension is enabled from the Xaneon Extensions -> Configuration -> Components
 * tab. 
 *
 * The gallery patch will not effect gallery's operation except when embedded inside
 * Mambo.
 *
 * Gallery Patch Information:
 * http://www.thegillis.net/programming_papers/php/mambo_and_gallery_sef_urls_with_fix.html
 *
 * Extension Information:
 **/

class sef_gallery {

	/**
	 * Removes all &amp;'s from a url back to regular &'s. Better for parsing.
	 **/
	function ampStrip($url) {
		$url = str_replace( '&amp;', '&', $url );
		return $url;
	}

	/**
	 * Creates the SEF advance URL out of the Mambo request
	 * Input: $string, string, The request URL (index.php?option=com_example&Itemid=$Itemid)
	 * Output: $sefstring, string, SEF advance URL ($var1/$var2/)
	 **/
	function create ($string) {
		// For clerification, I'll use /gallery as the component prefix. This is set in the
		// xaenon config file

		// This will convert the following:
		// Gallery main page:
		//	/index.php?option=com_gallery&Itemid=28 => /gallery/
		// Album pages
		//	/index.php?option=com_gallery&Itemid=28&set_albumName=album&include=view_album.php => /gallery/album/
		// Image pages
		//	/index.php?option=com_gallery&Itemid=28&set_albumName=album&id=image&include=view_photo.php => /gallery/album/image
		// Full image page
		//	/index.php?option=com_gallery&Itemid=28&set_albumName=album&id=image&include=view_photo.php&full=1 => /gallery/album/image?full=1
		//
		// Gallery appears to bypass the page code, but should still work.

		// Make sure we have a &amp; free string
		$string = sef_gallery::ampStrip($string);

		// This is the SEF string. Starts out as just the main gallery, no album selected
		$sefstring = "";

		// Check if there's an album name
		if (preg_match("/[\?&]set_albumName=([^&]*)/",$string,$matches)) {
			// make sef "album/"
			$sefstring .= $matches[1].'/';

			// Check for an image
			if (preg_match("/[\?&]id=([^&]*)/",$string,$matches)) {
				// make "album/image"
				$sefstring .= $matches[1];

				// now check if there's a full string
				if(preg_match("/[\?&]full=([0-9]+)/",$string,$matches)) {
					// make "album/image?full=1"
					$sefstring .= '?full='.$matches[1];
				}
			}
		}

		return $sefstring;
	}

    /**
    * Reverts to the Mambo query string out of the SEF advance URL
    * Input:
    *    $url_array, array, The SEF advance URL split in arrays (first custom virtual directory beginning at $pos+1)
    *    $pos, int, The position of the first virtual directory (component)
    * Output: $QUERY_STRING, string, Mambo query string (var1=$var1&var2=$var2)
    *    Note that this will be added to already defined first part (option=com_example&Itemid=$Itemid)
    **/
    function revert ($url_array, $pos) {

	    // The documentation says to declare the parameters as globals, but I think this is poor
	    // coding to register globals. If you absolutly need it, uncomment the following global line.
	    // Ideally no code should use this feature
	    //global $set_albumName, $id;

	    // $url_array == array( "component", "gallery", $album, $img );
	    if(count($url_array) != 4) {
		    error_log("Unknown parameter count to gallery extension! Found: ".count($url_array));
		    return "";
	    }

	    $set_albumName = $album = $url_array[2];

	    // check if there's a ?full=1 parameter
	    $fullArray = explode("?", $url_array[3]);
	    $id = $img = $fullArray[0];
	    // Fullstring will be appended to the request string if it is defined
	    $fullString = '';
	    if(isset($fullArray[1]) && $fullArray[1] == 'full=1') {
		    $fullString = '&full=11';
		    $_GET['full'] = '1';
		    $_REQUEST['full'] = '1';
	    }

	    // Now we can start building the internal url.
	    // First check if an image was requested
	    if(strlen($img) < 1) {
		    // it's an album they're trying to view
		    $_GET['set_albumName'] = $album;
		    $_REQUEST['set_albumName'] = $album;
		    $_GET['include'] = 'view_album.php';
		    $_REQUEST['include'] = 'view_album.php';
		    return "set_albumName=".$album."&include=view_album.php";
	    }
	    else {
		    // it's an image
		    $_GET['set_albumName'] = $album;
		    $_REQUEST['set_albumName'] = $album;
		    $_GET['id'] = $img;
		    $_REQUEST['id'] = $img;
		    return "set_albumName=".$album."&id=".$img."&include=view_photo.php".$fullString;
	    }
    }

}
?>