#include<sys/socket.h>
#include<sys/types.h>
#include<sys/stat.h>
#include<netinet/ip.h>
#include<arpa/inet.h>
#include<stdio.h>
#include<unistd.h>
#include<signal.h>
#include<stdlib.h>
#include<fcntl.h>
#include<string.h>
#include<pthread.h>

int skt; // Global.  This is the socket that the server will listen on
pthread_mutex_t new_client_mutex;

void close_server(int signal_number){
	printf("Closing down the server\n");
	close(skt);
}

char *words[128000];
size_t word_count = 0;
char dictionary_contents[1024*1024];
void load_dictionary(){
	char *filename = "/usr/share/dict/american-english";
	int fd = open(filename, O_RDONLY);
	if(fd == -1){
		perror("open");
		exit(1);
	}
	size_t readlen = read(fd, dictionary_contents, 1024*1024);
	char *prev_start = dictionary_contents;
	for(int i = 0; i < readlen; i++){
		if(dictionary_contents[i] == '\n'){
			words[word_count++] = prev_start;
			dictionary_contents[i] = 0;
			prev_start = dictionary_contents + i + 1;
		}
	}	
}

char* random_word(){
	size_t t = random() % word_count;
	return words[t];
}
void *handle_client(void* arg){
	char word_request;
	int client_fd = (long int)arg;
	while(1){
		size_t readlen = read(client_fd, &word_request, 1);
		if(word_request == '0')
			break;

		if(readlen == 1){
			for(int i = 0; i < word_request - '0'; i++){
				char* rw = random_word();
				printf("Sending word:  %s (%d)\n", rw, strlen(rw));
				write(client_fd, rw, strlen(rw));
				write(client_fd, "\n", 1);
			}
		}
	}

	close(client_fd);
}

int main(int argc, char ** argv){
	srandom((long int)(&argc));
	load_dictionary();
	struct sockaddr_in sad;
	sad.sin_port = htons(5142);
	sad.sin_addr.s_addr = INADDR_ANY;
	sad.sin_family = AF_INET;

	skt = socket(AF_INET, SOCK_STREAM, 0);
	if(skt == -1){
		perror("socket");
		return 1;
	}
	struct sigaction close_action;
	close_action.sa_handler = close_server;
	if(sigaction(SIGINT, &close_action, 0)){
		perror("sigaction");
		return 1;
	}

	if( bind(skt, (struct sockaddr *)(&sad), sizeof(struct sockaddr_in)) ){
		perror("bind");
		return 1;
	}
	if( listen(skt, 5) ){
		perror("listen");
		return 1;
	}	
	int client_fd;
	struct sockaddr_in client_address;
	socklen_t address_size = sizeof(struct sockaddr_in);
	for(;;){
		client_fd = accept(skt, (struct sockaddr *)(&client_address), &address_size);
		if(client_fd == -1){
			perror("accept");
			break;
		}
		printf("Connection made from address %s\n", inet_ntoa(client_address.sin_addr));
		// start a new thread for the new client
		pthread_t T;
		pthread_create(&T, 0, handle_client, (void*)(long int) client_fd); 
	}
	return 0;
}