<?php 
/* 
Plugin Name: FlexURL
Version: 0.2
Plugin URI: http://philhord.com/wp-hacks/flexurl
Description: Allows abbreviated post-slug lookups in case they were broken by email wrapping
Author: Phil Hord
Author URI: http://philhord.com
*/ 

/* 
** Mod log
**	06/08/05	phord	- redirect to correct page instead of showing data on "broken" URL
*/

$phord_old_query="";
$phord_unique_flexurl_marker="phord_match_string_unique_br549";
$phord_flexurl_pending_multi=FALSE;

// This gets called when the query_string is getting parsed.
// We need to catch the "name=" query arg and change it to 
// something we can recognize later.
function phord_query_filter($data) { 
	global $phord_old_query, $phord_unique_flexurl_marker;
	$phord_old_query = "";

	$out=$data;
	$x = strpos($data, "name=");
	if ($x > 0)  // make sure it's not something_name
	{
		$x = strpos($data, "&name=");
		if (!($x===FALSE)) ++$x;
	}

	if (!($x===FALSE)) {
	        $match=substr($data, $x+5);
	        $length=strcspn($match, "&");
	        $match=substr($match, 0, $length);
	        $out = substr($data, 0, $x) . "name=$phord_unique_flexurl_marker" . substr($data, $x+5+$length);
		$phord_old_query = $match;
	}
	return $out;
} 


// This filter gets called to parse the "where" clause for MYSQL for *all* lookups.
// Be very, very careful in here.
// We are essentially changing the query from "name = 'some_cutoff_name'" to "name LIKE 'some_cutoff_name%'"
// We use a little private marker up in phord_query_filter to make this easier.
function phord_where_filter($data) { 
	global $phord_old_query, $phord_unique_flexurl_marker;
	global $phord_flexurl_pending_multi;
	$phord_flexurl_pending_multi=FALSE;

	if (''==phord_old_query)
	    return $data;

	$out=$data;
	$x = strpos($data, "= '$phord_unique_flexurl_marker'");
	$length = strlen("= '$phord_unique_flexurl_marker'");
	if (!($x===FALSE)) {
	        $out = substr($data, 0, $x) . " like '$phord_old_query%' " . substr($data, $x+$length);
		$phord_flexurl_pending_multi = TRUE;
		
	}
	return $out;
} 

// This filter gets called after the list of posts is retrieved.
// We need to adjust some things to handle multiple posts in case
// multiple posts were returned even though the query was supposed
// to be for a single post originally.
function phord_posts_filter($posts) { 
	global $phord_flexurl_pending_multi;
	global $wp_query;
	global $phord_old_query;

	if ($phord_flexurl_pending_multi)
	{
		if (count($posts) > 1)
		{
			$wp_query->is_single = FALSE;
		}
		else
		{
			// Here we did a search on a partial or complete name that returned exactly one entry.
			// Check if the search name was complete.  If not, redirect to the correct location.
			$id = rtrim(get_permalink($posts[0]->ID), "/")."/";
			if (stristr($id, $phord_old_query."/") === FALSE)
			{
//				echo "<!-- ".get_permalink($posts[0]->ID).", ".$phord_old_query." -->";
				HEADER ( "HTTP/1.1 301 Moved Permanently" ); 
				HEADER ( "Location: " . get_permalink($posts[0]->ID) );
				exit(0);
			}
		}
	}
	$phord_flexurl_pending_multi=FALSE;

	return $posts;
} 

// Attach all our filters
add_filter('query_string', 'phord_query_filter');
add_filter('posts_where', 'phord_where_filter');
add_filter('the_posts', 'phord_posts_filter');

// make sure there's no blank spaces or lines after this line:
?>