<?php

class CWS_Non_Verbose_Page_Rules {
	public function __construct() {
		add_filter( 'post_rewrite_rules', array( $this, 'post_rewrite_rules' ) );
		add_filter( 'query_vars', array( $this, 'query_vars' ) );
		add_filter( 'request', array( $this, 'request' ) );
	}

	public function page_rewrite_rules( $rules ) {
		foreach ( $rules as $k => $v ) {
			$rules[$k] = str_replace( 'pagename=', 'post_or_page=', $v );
		}
		return $rules;
	}

	public function post_rewrite_rules( $rules ) {
		global $wp_rewrite;
		if ( $wp_rewrite->use_verbose_page_rules && preg_match( '#^/%postname%/?$#', $wp_rewrite->permalink_structure ) ) {
			$wp_rewrite->use_verbose_page_rules = false;
			add_filter( 'page_rewrite_rules', array( $this, 'page_rewrite_rules' ) );
			foreach ( $rules as $k => $v ) {
				// post attachment rule blocks 2nd level pages (e.g. level-1/level-2/), deal with it in page catchall
				if ( substr( $k, 0, 14 ) == '[^/]+/([^/]+)/' )
					unset( $rules[$k] );
				else
					$rules[$k] = str_replace( 'name=', 'post_or_page=', $v );
			}
		}
		return $rules;
	}

	public function query_vars( $vars ) {
		$vars[] = 'post_or_page';
		return $vars;
	}

	public function request( $request ) {
		if ( ! isset( $request['post_or_page'] ) )
			return $request;

		global $wpdb;
		if ( strpos( $request['post_or_page'], '/' ) !== false ) {
			$pieces = explode( '/', $request['post_or_page'] );
			$count = count( $pieces );
			// check for attachment matches first
			if ( ( $count == 2 ||
				$count == 3 && $pieces[2] == 'trackback' ||
				$count == 4 && $pieces[2] == 'feed' && in_array( $pieces[3], array('feed','rdf','rss','rss2','atom') ) ||
				$count == 3 && in_array( $pieces[2], array('feed','rdf','rss','rss2','atom') ) ||
				$count == 3 && preg_match( '/^comment-page-([0-9]{1,})$/', $pieces[2] ) ) &&
					$id = $wpdb->get_var( $wpdb->prepare( "SELECT ID FROM $wpdb->posts WHERE post_name = %s AND post_type = 'attachment' LIMIT 1", $pieces[1] ) ) )
				$request['attachment_id'] = $id;
			// otherwise this is definitely a page
			else
				$request['pagename'] = $request['post_or_page'];
		} else {
			//*
			$post_or_page = $wpdb->get_var( $wpdb->prepare( "SELECT post_type FROM $wpdb->posts WHERE post_name = %s AND post_type IN ('post','page') LIMIT 1", $request['post_or_page'] ) );
			if ( 'page' == $post_or_page )
				$request['pagename'] = $request['post_or_page'];
			else
				$request['name'] = $request['post_or_page'];
			//*/

			/* could try to be a bit smarter and get an ID now
			$results = $wpdb->get_results( $wpdb->prepare( "SELECT ID, post_type FROM $wpdb->posts WHERE post_name = %s AND post_type IN ('post','page') LIMIT 1", $request['post_or_page'] ) );
			if ( $results && $results[0]->post_type == 'page' )
				$request['page_id'] = $results[0]->ID;
			elseif ( $results )
				$request['p'] = $results[0]->ID;
			else
				$request['name'] = $request['post_or_page']; // 404
			//*/
		}

		unset( $request['post_or_page'] );
		return $request;
	}
}

new CWS_Non_Verbose_Page_Rules;