<?php
/**
 * Flight: An extensible micro-framework.
 *
 * @copyright   Copyright (c) 2011, Mike Cao <mike@mikecao.com>
 * @license     MIT, http://flightphp.com/license
 */

namespace flight\net;

/**
 * The Router class is responsible for routing an HTTP request to
 * an assigned callback function. The Router tries to match the
 * requested URL against a series of URL patterns. 
 */
class Router {
    /**
     * Mapped routes.
     *
     * @var array
     */
    protected $routes = array();

    /**
     * Pointer to current route
     *
     * @var int
     */
    protected $index = 0;

    /**
     * Gets mapped routes.
     *
     * @return array Array of routes
     */
    public function getRoutes() {
        return $this->routes;
    }

    /**
     * Clears all routes the router.
     */
    public function clear() {
        $this->routes = array();
    }

    /**
     * Maps a URL pattern to a callback function.
     *
     * @param string $pattern URL pattern to match
     * @param callback $callback Callback function
     */
    public function map($pattern, $callback) {
        if (strpos($pattern, ' ') !== false) {
            list($method, $url) = explode(' ', trim($pattern), 2);

            $methods = explode('|', $method);

            array_push($this->routes, new Route($url, $callback, $methods));
        }
        else {
            array_push($this->routes, new Route($pattern, $callback, array('*')));
        }
    }

    /**
     * Routes the current request.
     *
     * @param Request $request Request object
     * @return Route Matching route
     */
    public function route(Request $request) {
        while ($route = $this->current()) {
            if ($route !== false && $route->matchMethod($request->method) && $route->matchUrl($request->url)) {
                return $route;
            }
            $this->next();
        }

        return false;
    }

    /**
     * Gets the current route.
     *
     * @return Route
     */
    public function current() {
        return isset($this->routes[$this->index]) ? $this->routes[$this->index] : false;
    }

    /**
     * Gets the next route.
     *
     * @return Route
     */
    public function next() {
        $this->index++;
    }

    /**
     * Reset to the first route.
     */
    public  function reset() {
        $this->index = 0;
    }
}