/* What follows is code that ran before I added some comments and should run
 * after....This is student code and I am posting it because my code is
 * somewhere in the disk cloud of my stuff.  I will more fully comment later.
*/

/*important note: run client on wilkes with ./client 39394 134.173.42.100 stringtopass, and run server on knuth sa ./server 39394*/
/*Thus one more parameter, and not exactly the CS125 Class Project */

/*Majority of socket code was adapted from code a group member wrote in summer research with Prof. Breeden, which also involved some socket tests*/

/* These are the libraries that numerous 'man' commands will show as necessary
 * for Sockets
*/

/*this is the server*/
#include <stdio.h>
#include <sys/socket.h>
#include <stdlib.h>
#include <netinet/in.h>
#include <string.h>
#include <unistd.h>


int main(int argc, char *argv[]){
    /* need a port variable, socket address, various Socket parms */
	int port;   //port to listen to
	struct sockaddr_in address;  //socket address
	port = atoi(argv[1]); //get port from input
	address.sin_family = AF_INET; //use IPv4
	address.sin_port = htons(port); //link port to socket address

    /* go get and open a socket, set it up appropriately */
	int socketLoc = socket(AF_INET, SOCK_STREAM, 0); //initialize socket
	int opt = 1;

    /* this was done in lecture code */
	int err = setsockopt(socketLoc, SOL_SOCKET, SO_REUSEADDR | SO_REUSEPORT, &opt, sizeof(opt));   //eliminates address already in use
	if(err < 0){
                printf("Error with sockopt\n");
                exit(EXIT_FAILURE);
        }
    /* bind the socket, look at class FAQs on Sockets */
	err = bind(socketLoc, (struct sockaddr*)&address, sizeof(address));  //bind
	if(err < 0){
		printf("Error with bind\n");
		exit(EXIT_FAILURE);
	}
	/* Acquired, initialized and bound a Socket, how make it listen for a
     * servide request
     * Then Accept that request
     */
    listen(socketLoc, 3);  //listen
	int addrlen = sizeof(address);
	int new_socket = accept(socketLoc, (struct sockaddr*)&address, (socklen_t*)&addrlen); //accept incoming connection
	char buffer[10000000] = {0};
	err = read(new_socket, buffer, 10000000);  //read from buffer
	if(err < 0){
		printf("Error with read\n");
		exit(EXIT_FAILURE);
	}

	/*find actual numbe of characters read*/
	long unsigned int i;
	for(i=0;i<10000000;i++){
		if(buffer[i] == 0){
			break;
		}
	}

	/*send message*/
	err = send(new_socket, buffer, sizeof(buffer),0);
	if(err < 0){
                printf("Error with send\n");
                exit(EXIT_FAILURE);
        }

	/*print bytes received*/
	printf("Server: received and echoed %lu bytes from 134.173.42.167\n", i);
	return 0;
}