/*
 * This is a better server than simple_server.c
 * I'm only going to comment changes from simple_server.c
 * So if there's something that doesn't make any sense in here, maybe look at that one.
 */
#include<sys/socket.h>
#include<sys/types.h>
#include<netinet/ip.h>
#include<arpa/inet.h>
#include<stdio.h>
#include<unistd.h>
#include<signal.h>
#include<stdlib.h>
#include<string.h>

#include "looking_glass.h"

int skt;
void shut_down_server(int signal){
	printf("\nDoing everything we need to do to shut down the server\n");
	close(skt);
	exit(0); 
}

int main(int argc, char ** argv){
	uint16_t listen_port = 5141; // 5141 is the default
	if(argc > 1){
		listen_port = atoi(argv[1]);
		if(listen_port < 1){
			printf("Invalid port:  %s\n", argv[1]);
			exit(1);
		}
		printf("Will listen on port %d\n", listen_port);
	} else {
		printf("No port specified, defaulting to %d\n", listen_port);
	}	
	struct sigaction sa;
	sa.sa_handler = shut_down_server;
	sigaction(SIGINT, &sa, 0);

	struct sockaddr_in sad;
	sad.sin_port = htons(listen_port);
	sad.sin_addr.s_addr = INADDR_ANY;
	sad.sin_family = AF_INET;

	skt = socket(AF_INET, SOCK_STREAM, 0); // Step 1
	if(skt == -1){
		perror("socket");
		return 1;
	}
	if( bind(skt, (struct sockaddr *)(&sad), sizeof(struct sockaddr_in)) ){ // step 2
		perror("bind");
		return 1;
	}
	if( listen(skt, 5) ){ // step 3
		perror("listen");
		return 1;
	}	
	int client_fd;
	struct sockaddr_in client_address;
	socklen_t address_size = sizeof(struct sockaddr_in);
	while(1){
		client_fd = accept(skt, (struct sockaddr *)(&client_address), &address_size); // step 4
		printf("Connection made from address %s\n", inet_ntoa(client_address.sin_addr));
		/* Sending method:  Array of Characters  */
		unsigned char version_message[5];
		version_message[0] = 14;
		version_message[1] = 5;	
		version_message[2] = 7;	
		version_message[3] = 0;	
		version_message[4] = 0;
		write(client_fd, version_message, 5);
		// next:  Send a game message out
		// type:  11 (1 byte)
		// initial points:  637 (2 bytes)
		// stat limit:  637 (2 bytes)
		// description length:  strlen(description) (2 bytes)
		// description:  ...

		char *description = looking_glass;
		/* Sending method:  Individual Variables */
		char type = 11;
		uint16_t initial_points = 637;
		uint16_t stat_limit = 637;
		uint16_t description_length = strlen(description);
		// description was specified above, so we could use strlen
		printf("Description length is %d\n", description_length);

		write(client_fd, &type, 1);
		write(client_fd, &initial_points, 2);
		write(client_fd, &stat_limit, 2);
		write(client_fd, &description_length, 2);
		write(client_fd, description, description_length);

		close(client_fd);
	}
	return 0;
}