export async function getLoadBalancer(SPN, endpointUrl: string, name: string, resourceGroupName: string) {
	
	var deferred = Q.defer<any>();    
	var restUrl = "https://management.azure.com/subscriptions/" + SPN.subscriptionId + "/resourceGroups/" + resourceGroupName + "/providers/Microsoft.Network/loadBalancers/" + name + "?api-version=" + azureApiVersion;
	var accessToken = await getAccessToken(SPN, endpointUrl);

	var requestHeader = {
		authorization: 'Bearer ' + accessToken
	}

	tl.debug(`Getting the load balancer: ${name}`);
	httpObj.get('GET', restUrl, requestHeader, (error, response, body) => {
        if(error) {
            deferred.reject(error);
        }
        else if(response.statusCode === 200) {
            deferred.resolve(JSON.parse(body));
        }
        else {
        	deferred.reject(tl.loc("CouldNotFetchLoadBalancer", name, response.statusCode, response.statusMessage, body));
        }
    });
	
    return deferred.promise;
}
    private getAuthorizationToken(): Q.Promise<string> {
        var deferred = Q.defer<string>();
        var oauthTokenRequestUrl = this.authorityUrl + this.domain + "/oauth2/token/";
        var requestData = querystring.stringify({
            resource: this.armUrl,
            client_id: this.clientId,
            grant_type: "client_credentials",
            client_secret: this.secret
        });
        var requestHeader = {
            "Content-Type": "application/x-www-form-urlencoded; charset=utf-8"
        };

        tl.debug('Requesting for Auth Token: ' + oauthTokenRequestUrl);
        httpObj.send('POST', oauthTokenRequestUrl, requestData, requestHeader, (error, response, body) => {
            if (error) {
                deferred.reject(error);
            }
            else if (response.statusCode == 200) {
                deferred.resolve(JSON.parse(body).access_token);
            }
            else {
                deferred.reject(tl.loc('CouldNotFetchAccessTokenforAzureStatusCode', response.statusCode, response.statusMessage));
            }
        });
        return deferred.promise;
    }
function getAccessToken(SPN, endpointUrl: string): Q.Promise<string> {

	var deferred = Q.defer<string>();
	var authorityUrl = authUrl + SPN.tenantID + "/oauth2/token/";

	var post_data = querystring.stringify({
		resource: endpointUrl, 
		client_id: SPN.servicePrincipalClientID,
		grant_type: "client_credentials", 
		client_secret: SPN.servicePrincipalKey
	});

	var requestHeader = {
		"Content-Type": "application/x-www-form-urlencoded; charset=utf-8"
	};

	tl.debug(`Requesting for bearer token ${authorityUrl}`);
	httpObj.send("POST", authorityUrl, post_data, requestHeader, (error, response, body) => {
		if(error) {
			deferred.reject(error);
		}
		else if (response.statusCode == 200) {
			deferred.resolve(JSON.parse(body).access_token);
		}
		else {
			deferred.reject(tl.loc("CouldNotFetchAcessToken", response.statusCode, response.statusMessage, body));
		};
	}); 

    return deferred.promise;
}
export async function getNetworkInterfacesInRG(SPN, endpointUrl: string, resourceGroupName: string) {

	var deferred = Q.defer<any>();
	var restUrl = SPN.url + "subscriptions/" + SPN.subscriptionId + "/resourceGroups/" + resourceGroupName + "/providers/Microsoft.Network/networkInterfaces?api-version=" + azureApiVersion;
	var accessToken = await getAccessToken(SPN, endpointUrl);

	var requestHeader = {
		Authorization: 'Bearer ' + accessToken
	};

	tl.debug(`Getting all network interfaces in the resource group ${resourceGroupName}`);
	httpObj.get('GET', restUrl, requestHeader, (error, response, body) => {
		if(error) {
			deferred.reject(error);
		}
		else if(response.statusCode == 200) {
			deferred.resolve(JSON.parse(body).value);
		}
		else {
			deferred.reject(tl.loc("CouldNotFetchNetworkInterfacesInRg", resourceGroupName, response.statusCode, response.statusMessage, body));
		}

	});
	return deferred.promise;
}
	setTimeout (function putNetworkInterface() {
		if(retryCount > maxRetries) {
			deferred.reject(tl.loc("MaxRetriesExceededForSettingNetworkInterface", nic.name));
			return;
		}
		
		tl.debug(`Trial Count = ${retryCount}`);
		httpObj.send("PUT", restUrl, JSON.stringify(nic, null, 2), requestHeader, (error, response, body) => {
	        if(error) {
	            deferred.reject(error); 
	        }
	        else if(response.statusCode == 200) {	

	        	// wait for the provisioning state to be succeeded
	        	// check after every 20 seconds
	        	var asyncUrl = response.headers["azure-asyncoperation"];
	        	var checkStatusRetryCount = 0;
	        	var checkStatusWaitTime = 20000;
	        	setTimeout( async function checkSuccessStatus() {
	        		try {
	        			var provisioningState =  await checkProvisioningState(asyncUrl, accessToken);
	        			tl.debug("Status = " + provisioningState);
	        			if(provisioningState == "Succeeded") {
	        				return deferred.resolve("setNICStatusSuccess");
	        			}
	        		}
	        		catch(error) {
	        			// ignore errors and retry setting the network interface
	        			tl.debug(`Checking provisioning state errored out : ${error}`);
	        			retryCount++;
	        			tl.debug("Retrying setting network interface after " + sleepTime/1000 + " sec");
	        			return setTimeout(putNetworkInterface, sleepTime);
	        		}
	        		if(++checkStatusRetryCount == 10) {
	        			// Retry setting the network interface
	        			retryCount++;
	        			tl.debug("Retrying setting network interface after " + sleepTime/1000 + " sec");
	        			setTimeout(putNetworkInterface, sleepTime);
	        		}
					else {
						// Re-check the status of the provisioning state
						setTimeout(checkSuccessStatus, checkStatusWaitTime);
					}
	        	}, 1);
	        }
	        else if(response.statusCode == 429){
	        	body = JSON.parse(body);
	        	if(body["error"] && body["error"].code == "RetryableError") {
	        		retryCount++;
	        		tl.debug(JSON.stringify(body, null, 4));
        			tl.debug("Retrying setting network interface after " + sleepTime/1000 + " sec");
        			setTimeout(putNetworkInterface, sleepTime);
	        	}
	        }
	        else {
	        	deferred.reject(tl.loc("FailedSettingNetworkInterface", nic.name, response.statusCode, response.statusMessage, body));
	        }
		});
	}, 1);
 return new Promise<WebResponse>((resolve, reject) => {
     httpObj.send(request.method, request.uri, request.body, request.headers, (error, response, body) => {
         if (error) {
             reject(error);
         }
         else {
             var httpResponse = toWebResponse(response, body);
             resolve(httpResponse);
         }
     });
 });
async function checkProvisioningState(url: string, accessToken: string) {
	var deferred = Q.defer();
	var headers = {
		Authorization: "Bearer " + accessToken
	};
	httpObj.get("GET", url, headers, (error, response, body) => {
		if(error){
			deferred.reject(error);
		}
		else if(response.statusCode == 200) {
			deferred.resolve(JSON.parse(body).status);
		}
		else {
			deferred.reject(body);
		}
	});
	return deferred.promise;	
}