<?php
/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

define("LOCATION_SERVICE_PRODUCT_NAME", "Location");
define("LOCATION_SERVICE_DOMAIN", "location.aliyuncs.com");
define("LOCATION_SERVICE_VERSION", "2015-06-12");
define("LOCATION_SERVICE_DESCRIBE_ENDPOINT_ACTION", "DescribeEndpoints");
define("LOCATION_SERVICE_REGION", "cn-hangzhou");
define("CACHE_EXPIRE_TIME", 3600);

class DescribeEndpointRequest extends RpcAcsRequest
{
	function __construct($id, $serviceCode, $endPointType) {
		parent::__construct(LOCATION_SERVICE_PRODUCT_NAME, LOCATION_SERVICE_VERSION, LOCATION_SERVICE_DESCRIBE_ENDPOINT_ACTION);
		
		$this->queryParameters["Id"] = $id;
		$this->queryParameters["ServiceCode"] = $serviceCode;
		$this->queryParameters["Type"] = $endPointType;
		$this->setRegionId(LOCATION_SERVICE_REGION);
		
		$this->setAcceptFormat("JSON");
	}
}

class LocationService
{	
	private $clientProfile;
	public static $cache = array();
	public static $lastClearTimePerProduct = array();
	public static $serviceDomain = LOCATION_SERVICE_DOMAIN;
	
	function __construct($clientProfile) {
		$this->clientProfile = $clientProfile;
	}
	
	public function findProductDomain($regionId, $serviceCode, $endPointType, $product)
	{
		$key = $regionId.'#'.$product;
		@$domain = self::$cache[$key];
		if ($domain == null || $this->checkCacheIsExpire($key) == true)
		{
			$domain = $this->findProductDomainFromLocationService($regionId, $serviceCode, $endPointType);
            self::$cache[$key] = $domain;
		}

		return $domain;
	}

	public static function addEndPoint($regionId, $product, $domain)
    {
        $key = $regionId.'#'.$product;
        self::$cache[$key] = $domain;
        $lastClearTime = mktime(0, 0, 0, 1, 1, 2999);
        self::$lastClearTimePerProduct[$key] = $lastClearTime;
    }

    public static function modifyServiceDomain($domain)
    {
        self::$serviceDomain = $domain;
    }

	private function checkCacheIsExpire($key)
    {
        $lastClearTime = self::$lastClearTimePerProduct[$key];
        if ($lastClearTime == null)
        {
            $lastClearTime = time();
            self::$lastClearTimePerProduct[$key] = $lastClearTime;
        }

        $now = time();
        $elapsedTime = $now - $lastClearTime;

        if ($elapsedTime > CACHE_EXPIRE_TIME)
        {
            $lastClearTime = time();
            self::$lastClearTimePerProduct[$key] = $lastClearTime;
            return true;
        }

        return false;
    }
	
	private function findProductDomainFromLocationService($regionId, $serviceCode, $endPointType)
	{
		$request = new DescribeEndpointRequest($regionId, $serviceCode, $endPointType);
		
		$signer = $this->clientProfile->getSigner();
		$credential = $this->clientProfile->getCredential();
		
		$requestUrl = $request->composeUrl($signer, $credential, self::$serviceDomain);
		
		$httpResponse = HttpHelper::curl($requestUrl, $request->getMethod(), null, $request->getHeaders());
		
		if (!$httpResponse->isSuccess())
		{
			return null;
		}

		$respObj = json_decode($httpResponse->getBody());
		return $respObj->Endpoints->Endpoint[0]->Endpoint;
	}
}