<?php
/*
Plugin Name: Query Redirect Rewrite
Plugin URI: http://boren.nu/
Description: Example plugin demonstrating how to add query vars, load custom templates, and genereate rewrite rules.
Author: Ryan Boren
Author URI: http://boren.nu/
*/

$qrr_rewrite_tag = '%qrr%';
$qrr_query_var = 'qrr';
$qrr_link_base = 'qrr';

// This generates the rules to handle /qrr/%qrr%/.
function qrr_generate_rewrite($wp_rewrite) {
	global $qrr_rewrite_tag, $qrr_query_var, $qrr_link_base;

	// Add the tag, pattern, and query.  This replaces %link_category% in the
	// permalink structure with the regex ([^/]+).  The query string will
	// have link_category set to whatever the regex matched.
	$wp_rewrite->add_rewrite_tag($qrr_rewrite_tag, '([^/]+)', "{$qrr_query_var}=");
	// Create the structure off of root.
	$structure = $wp_rewrite->root . $qrr_link_base . "/{$qrr_rewrite_tag}";
	//  Make those rules
	$rules = $wp_rewrite->generate_rewrite_rule($structure);
	// Append the rules to the rules array in the rewrite object.
	$wp_rewrite->rules += $rules;
}

// This adds qrr as a recognized query var. It will be processed out
// of GET, PATH_INFO, or REQUEST_URI depending on how the permalink was
// requested. WP handles the particulars, you don't have to care. The value
// of qrr will be made available via the WP_Query object and
// get_query_var().
function qrr_add_query_var($vars) {
	global $qrr_query_var;

	// Append qrr.
	$vars[] = $qrr_query_var;
	// Don't forget to return the array.
	return $vars;
}

// If qrr is set, redirect to qrr.php.
function qrr_template_redirect() {
	global $qrr_query_var;
	
	// Get the qrr from WP_Query.
	$qrr = get_query_var($qrr_query_var);

	// If it's empty, return.
	if (empty($qrr))
		return;

	// Otherwise, load our template.
	// You must use load_template rather than require or include.
	// load_template() sets up the necessary environment.
	load_template(ABSPATH . "wp-content/{$qrr_query_var}.php");
	// Make sure you exit after loading a template.
	exit;
}

// Hook 'em in.
add_filter('query_vars', 'qrr_add_query_var');
add_action('generate_rewrite_rules', 'qrr_generate_rewrite');
add_action('template_redirect', 'qrr_template_redirect');
?>