<?php
/*
 * Copyright 2008 Marc Mongenet
 *
 * 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.
 *
 */


handle_request();
exit;


# Check if the request is valid, and process it if so.
function handle_request() {
	try {
		require_once 'defines.php';
		require_once 'http.php';
		require_once 'log.php';
		require_once 'str.php';
		require_once 'uri.php';

		configure_php_interpreter();
		$query_doc_name = get_http_parameter(W2ML_QUERY_PARAM);
		check_w2ml_query_param($query_doc_name);
		require 'process_request.php';
		process_request('site:///'.$query_doc_name);
	}
	catch (RequestException $e) {
		log_error($e->getMessage(), DEFAULT_LOG_LIMIT, LOG_ERR);
		emit_http_error(404);
	}
	catch (ResourceUriException $e) {
		log_error($e->getMessage(), DEFAULT_LOG_LIMIT, LOG_ERR);
		emit_http_error(404);
	}
	catch (ResourcePathException $e) {
		log_error($e->getMessage(), DEFAULT_LOG_LIMIT, LOG_ERR);
		emit_http_error(404);
	}
	catch (ResourceOpenException $e) {
		log_error($e->getMessage(), DEFAULT_LOG_LIMIT, LOG_ERR);
		emit_http_error(403);
	}
	catch (ResourceLoadException $e) {
		log_error($e->getMessage(), DEFAULT_LOG_LIMIT, LOG_ERR);
		emit_http_error(500);
	}
	catch (DocumentParseException $e) {
		log_error($e->getMessage(), DEFAULT_LOG_LIMIT, LOG_ERR);
		emit_http_error(500);
	}
	catch (Exception $e) {
		log_error($e->getMessage(), DEFAULT_LOG_LIMIT, LOG_ERR);
		emit_http_error(500);
	}
}


function configure_php_interpreter() {
	if (DEFAULT_LOG_LIMIT !== LOG_DEBUG) {
		error_reporting(0);
	}
	mb_internal_encoding('UTF-8');
	libxml_use_internal_errors(TRUE);
}


class RequestException extends Exception {}


function check_w2ml_query_param($value) {
	if (!is_string($value)) {
		throw new RequestException
			('Missing '.W2ML_QUERY_PARAM.' HTTP request parameter');
	}
	if ($value === '') {
		throw new RequestException
			('Missing '.W2ML_QUERY_PARAM.' HTTP request parameter value');
	}
}


function emit_http_error($error_number) {
	static $errors_text = array(
		400 => 'Bad Request',
		403 => 'Forbidden',
		404 => 'Not Found',
		500 => 'Internal Server Error'
	);
	header('Status: '.$error_number.' '.$errors_text[$error_number]);
	header('HTTP/1.0 '.$error_number.' '.$errors_text[$error_number]);
	echo http_error_in_xhtml('Error '.$error_number.': '.$errors_text[$error_number]);
}

?>