#define _WINSOCK_DEPRECATED_NO_WARNINGS
#define _CRT_SECURE_NO_WARNINGS
#include <iostream>
using namespace std;
// Don't forget to include "ws2_32.lib" in the library list.
#include <winsock2.h>
#include <string.h>
#define TIME_PORT	27015

void main()
{
	const int SIZE = 100;

	// Initialize Winsock (Windows Sockets).

	WSAData wsaData;
	if (NO_ERROR != WSAStartup(MAKEWORD(2, 2), &wsaData))
	{
		cout << "Time Client: Error at WSAStartup()\n";
	}

	// Client side:
	// Create a socket and connect to an internet address.

	SOCKET connSocket = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
	if (INVALID_SOCKET == connSocket)
	{
		cout << "Time Client: Error at socket(): " << WSAGetLastError() << endl;
		WSACleanup();
		return;
	}

	// For a client to communicate on a network, it must connect to a server.

	// Need to assemble the required data for connection in sockaddr structure.

	// Create a sockaddr_in object called server.
	sockaddr_in server;
	server.sin_family = AF_INET;
	server.sin_addr.s_addr = inet_addr("127.0.0.1");
	server.sin_port = htons(TIME_PORT);

	// Send and receive data.

	int bytesSent = 0;
	int bytesRecv = 0;
	char sendBuff[255] = "What's the time?";
	char recvBuff[255];
	int choise;
	bool stop = false;
	bool delayEstimationFlag = false;
	bool measureRTTFlag = false;

	while (stop == false) {

		cout << "\nCLIENT: Choose a message to send:\n\n";
		cout << "1 - GetTime\n";
		cout << "2 - GetTimeWithoutDate\n";
		cout << "3 - GetTimeSinceEpoch\n";
		cout << "4 - GetClientToServerDelayEstimation\n";
		cout << "5 - MeasureRTT\n";
		cout << "6 - GetTimeWithoutDateOrSeconds\n";
		cout << "7 - GetYear\n";
		cout << "8 - GetMonthAndDay\n";
		cout << "9 - GetSecondsSinceBeginingOfMonth\n";
		cout << "10 - GetDayOfYear\n";
		cout << "11 - GetDaylightSavings\n";
		cout << "12 - Exit\n\n";
		cout << "Your choise: ";
		cin >> choise;

		while (!(choise <= 12 && choise >= 1)) {
			cout << "\nInvalid input. Please enter a valid choise: ";
			cin >> choise;
		}

		if (choise == 1) {
			strcpy(sendBuff, "GetTime");
		}
		else if (choise == 2) {
			strcpy(sendBuff, "GetTimeWithoutDate");
		}
		else if (choise == 3) {
			strcpy(sendBuff, "GetTimeSinceEpoch");
		}
		else if (choise == 4) {
			strcpy(sendBuff, "GetClientToServerDelayEstimation");
			delayEstimationFlag = true;
		}
		else if (choise == 5) {
			strcpy(sendBuff, "MeasureRTT");
			measureRTTFlag = true;
		}
		else if (choise == 6) {
			strcpy(sendBuff, "GetTimeWithoutDateOrSeconds");
		}
		else if (choise == 7) {
			strcpy(sendBuff, "GetYear");
		}
		else if (choise == 8) {
			strcpy(sendBuff, "GetMonthAndDay");
		}
		else if (choise == 9) {
			strcpy(sendBuff, "GetSecondsSinceBeginingOfMonth");
		}
		else if (choise == 10) {
			strcpy(sendBuff, "GetDayOfYear");
		}
		else if (choise == 11) {
			strcpy(sendBuff, "GetDaylightSavings");
		}
		else if (choise == 12) {
			stop = true;
			WSACleanup();
		}

		if (delayEstimationFlag) {
			double sum = 0;
			int temp;
			for (int i = 0; i < SIZE; i++) {
				strcpy(sendBuff, "GetClientToServerDelayEstimation");
				bytesSent = sendto(connSocket, sendBuff, (int)strlen(sendBuff), 0, (const sockaddr *)&server, sizeof(server));
				if (SOCKET_ERROR == bytesSent)
				{
					cout << "Time Client: Error at sendto(): " << WSAGetLastError() << endl;
					closesocket(connSocket);
					WSACleanup();
					return;
				}
				cout << "Time Client: Sent: " << bytesSent << "/" << strlen(sendBuff) << " bytes of \"" << sendBuff << "\" message.\n";
			}

			for (int i = 0; i < SIZE; i++) {
				bytesRecv = recv(connSocket, recvBuff, 255, 0);
				recvBuff[bytesRecv] = '\0'; //add the null-terminating to make it a string
				if (i > 0) {
					sum += atoi(recvBuff) - temp;
				}
				temp = atoi(recvBuff);
				if (SOCKET_ERROR == bytesRecv)
				{
					cout << "Time Client: Error at recv(): " << WSAGetLastError() << endl;
					closesocket(connSocket);
					WSACleanup();
					return;
				}

				cout << "Time Client: Recieved: " << bytesRecv << " bytes of \"" << recvBuff << "\" message.\n";
			}

			cout << "\n\nDelay Estimation between client and server is: " << sum / 100 << " ms\n";
			delayEstimationFlag = false;
		}
		else if (measureRTTFlag) {
			double sum = 0;
			DWORD temp;
			for (int i = 0; i < SIZE; i++) {
				strcpy(sendBuff, "MeasureRTT");
				temp = GetTickCount();
				bytesSent = sendto(connSocket, sendBuff, (int)strlen(sendBuff), 0, (const sockaddr *)&server, sizeof(server));
				if (SOCKET_ERROR == bytesSent)
				{
					cout << "Time Client: Error at sendto(): " << WSAGetLastError() << endl;
					closesocket(connSocket);
					WSACleanup();
					return;
				}
				cout << "Time Client: Sent: " << bytesSent << "/" << strlen(sendBuff) << " bytes of \"" << sendBuff << "\" message.\n";

				// Gets the server's answer using simple recieve (no need to hold the server's address).
				bytesRecv = recv(connSocket, recvBuff, 255, 0);
				recvBuff[bytesRecv] = '\0'; //add the null-terminating to make it a string
				sum += GetTickCount() - temp;
				if (SOCKET_ERROR == bytesRecv)
				{
					cout << "Time Client: Error at recv(): " << WSAGetLastError() << endl;
					closesocket(connSocket);
					WSACleanup();
					return;
				}

				cout << "Time Client: Recieved: " << bytesRecv << " bytes of \"" << recvBuff << "\" message.\n";
			}

			cout << "\n\nDelay Estimation between client and server is: " << sum / 100 << " ms\n";
			measureRTTFlag = false;
		}
		else {
			// Asks the server what's the currnet time.
			// The send function sends data on a connected socket.
			// The buffer to be sent and its size are needed.
			// The fourth argument is an idicator specifying the way in which the call is made (0 for default).
			// The two last arguments hold the details of the server to communicate with.
			// NOTE: the last argument should always be the actual size of the client's data-structure (i.e. sizeof(sockaddr)).
			bytesSent = sendto(connSocket, sendBuff, (int)strlen(sendBuff), 0, (const sockaddr *)&server, sizeof(server));
			if (SOCKET_ERROR == bytesSent)
			{
				cout << "Time Client: Error at sendto(): " << WSAGetLastError() << endl;
				closesocket(connSocket);
				WSACleanup();
				return;
			}
			cout << "Time Client: Sent: " << bytesSent << "/" << strlen(sendBuff) << " bytes of \"" << sendBuff << "\" message.\n";

			// Gets the server's answer using simple recieve (no need to hold the server's address).
			bytesRecv = recv(connSocket, recvBuff, 255, 0);
			if (SOCKET_ERROR == bytesRecv)
			{
				cout << "Time Client: Error at recv(): " << WSAGetLastError() << endl;
				closesocket(connSocket);
				WSACleanup();
				return;
			}

			recvBuff[bytesRecv] = '\0'; //add the null-terminating to make it a string
			cout << "Time Client: Recieved: " << bytesRecv << " bytes of \"" << recvBuff << "\" message.\n";
		}
	}

	// Closing connections and Winsock.
	cout << "Time Client: Closing Connection.\n";
	closesocket(connSocket);
	WSACleanup();
}