#include <stdio.h>
#include <stdlib.h>
#include "../../basext.h"
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <netdb.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <sys/socket.h>

#define MAXDATASIZE 256

besVERSION_NEGOTIATE
    return (int)INTERFACE_VERSION;
besEND

besSUB_START
        printf ("Simple Socket module version 1 loaded.\n");
	printf ("Released december 27, 2001.\n");
besEND

besSUB_FINISH
besEND

besFUNCTION (__ss_connect)
        VARIABLE ptr;
        char* arg0;
        long arg1;
        int sockfd;
        struct hostent *he;
        struct sockaddr_in their_addr;					// connector's address information

        if(besARGNR<2) return EX_ERROR_TOO_FEW_ARGUMENTS;
        if(besARGNR>2) return EX_ERROR_TOO_MANY_ARGUMENTS;

        ptr = besARGUMENT(1);
        besDEREFERENCE(ptr);
        arg0 = besCONVERT2ZCHAR(besCONVERT2STRING(ptr),arg0);

        ptr = besARGUMENT(2);
        besDEREFERENCE(ptr);
        arg1 = besGETLONGVALUE(ptr);

        sockfd = 0;

        if ((he=gethostbyname(arg0)) == NULL) {  			// get the host info
            printf ("\nSpecified host does not exist!\n");
            sockfd = -1;
        }

        else if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
            printf("\nCannot connect to socket!\n");
            sockfd = -2;
        }

        else {
          their_addr.sin_family = AF_INET;    				// host byte order
          their_addr.sin_port = htons(arg1);				// short, network byte order
          their_addr.sin_addr = *((struct in_addr *)he->h_addr);
          memset(&(their_addr.sin_zero), '\0', 8);			// zero the rest of the struct

          if (connect(sockfd, (struct sockaddr *)&their_addr, sizeof(struct sockaddr)) == -1) {
              printf("Unable to connect to specified host!\n");
              sockfd = -3;
          }
	  else printf("Socket connected.\n");
	}
        besALLOC_RETURN_LONG;
        LONGVALUE(besRETURNVALUE) = sockfd;

        besFREE (arg0);
besEND

besFUNCTION (__ss_disconnect)
        VARIABLE ptr;
	long arg0;

        if(besARGNR<1) return EX_ERROR_TOO_FEW_ARGUMENTS;
        if(besARGNR>1) return EX_ERROR_TOO_MANY_ARGUMENTS;

        ptr = besARGUMENT(1);
        besDEREFERENCE(ptr);
        arg0 = besGETLONGVALUE(ptr);

        close(arg0);
	printf("Socket disconnected.\n");

        besRETURNVALUE = NULL;
besEND

besFUNCTION (__ss_check)
        VARIABLE ptr;
	long arg0;
	fd_set read_available;
        struct timeval tv;
        int returnvalue;

        if(besARGNR<1) return EX_ERROR_TOO_FEW_ARGUMENTS;
        if(besARGNR>1) return EX_ERROR_TOO_MANY_ARGUMENTS;

        ptr = besARGUMENT(1);
        besDEREFERENCE(ptr);
        arg0 = besGETLONGVALUE(ptr);

        returnvalue = 0;

        FD_ZERO(&read_available);
	FD_SET(arg0, &read_available);

        tv.tv_sec = 0;
        tv.tv_usec = 0;
        select(arg0+1, &read_available, NULL, NULL, &tv);

        if (FD_ISSET(arg0, &read_available)){
            printf("There is new data.\n");
            returnvalue = 1;
        }

        besALLOC_RETURN_LONG;
        LONGVALUE(besRETURNVALUE) = returnvalue;
besEND

besFUNCTION (__ss_read)
        VARIABLE ptr;
	long arg0;
	int numbytes, i;
	char buf[MAXDATASIZE];
        char* retstr;

        if(besARGNR<1) return EX_ERROR_TOO_FEW_ARGUMENTS;
        if(besARGNR>1) return EX_ERROR_TOO_MANY_ARGUMENTS;

        ptr = besARGUMENT(1);
        besDEREFERENCE(ptr);
        arg0 = besGETLONGVALUE(ptr);

	numbytes = recv(arg0, buf, MAXDATASIZE-1, 0);

        if (numbytes == -1) {
            printf("Error reading from socket!\n");
            retstr = "SIMPLE SOCKET ERROR 1";
        }

        else if (numbytes == 0){
            printf("Remote side has closed connection!\n");
            retstr = "SIMPLE SOCKET ERROR 2";
        }

	else {
        buf[numbytes-1] = '\n';
        buf[numbytes] = '\0';

        retstr = (char*)buf;
	printf("Data received.\n");
	}

        besALLOC_RETURN_STRING(strlen(retstr));
        memcpy(STRINGVALUE(besRETURNVALUE),retstr,strlen(retstr));
besEND

besFUNCTION (__ss_write)
        VARIABLE ptr;
	long arg0, bytes_sent;
        char* arg1;

        if(besARGNR<2) return EX_ERROR_TOO_FEW_ARGUMENTS;
        if(besARGNR>2) return EX_ERROR_TOO_MANY_ARGUMENTS;

        ptr = besARGUMENT(1);
        besDEREFERENCE(ptr);
        arg0 = besGETLONGVALUE(ptr);

        ptr = besARGUMENT(2);
        besDEREFERENCE(ptr);
        arg1 = besCONVERT2ZCHAR(besCONVERT2STRING(ptr),arg1);

	bytes_sent = send(arg0, arg1, strlen(arg1), 0);

        if (bytes_sent<strlen(arg1)){
	    printf("Some bytes were lost!");
        }

        printf("Data sent.\n");

        besALLOC_RETURN_LONG;
        LONGVALUE(besRETURNVALUE) = bytes_sent;

        besFREE (arg1);
besEND

besFUNCTION (__ss_server)
        VARIABLE ptr;
        char* arg0;
        long arg1, arg2;
        int sockfd;
        int yes = 1;
        struct hostent *he;
        struct sockaddr_in my_addr;					// my address information

        if(besARGNR<3) return EX_ERROR_TOO_FEW_ARGUMENTS;
        if(besARGNR>3) return EX_ERROR_TOO_MANY_ARGUMENTS;

        ptr = besARGUMENT(1);
        besDEREFERENCE(ptr);
        arg0 = besCONVERT2ZCHAR(besCONVERT2STRING(ptr),arg0);

        ptr = besARGUMENT(2);
        besDEREFERENCE(ptr);
        arg1 = besGETLONGVALUE(ptr);

        ptr = besARGUMENT(3);
        besDEREFERENCE(ptr);
        arg2 = besGETLONGVALUE(ptr);

        sockfd = 0;

        if ((he=gethostbyname(arg0)) == NULL) {  			// get the host info
            printf ("\nSpecified host does not exist!\n");
            sockfd = -1;
        }

	else if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
            printf("\nCannot connect to socket!\n");
            sockfd = -2;
        }

        else if (setsockopt(sockfd,SOL_SOCKET,SO_REUSEADDR,&yes,sizeof(int)) == -1) {
            printf("\nCannot configure socket!\n");
            sockfd = -3;
        }

        else {
          my_addr.sin_family = AF_INET;
          my_addr.sin_port = htons(arg1);     				// Fill in specified port
          my_addr.sin_addr = *((struct in_addr *)he->h_addr);		// Fill in specified IP address
          memset(&(my_addr.sin_zero), '\0', 8);				// zero the rest of the struct

          if (bind(sockfd, (struct sockaddr *)&my_addr, sizeof(struct sockaddr)) == -1) {
                printf("Unable to bind the specified socket address!\n");
                sockfd = -4;
          }

          else if (listen(sockfd, arg2) == -1) {
                printf("Unable to listen to the specified socket address!\n");
                sockfd = -5;
          }
          else printf("Server started.\n");
          }

        besALLOC_RETURN_LONG;
        LONGVALUE(besRETURNVALUE) = sockfd;

        besFREE (arg0);
besEND

besFUNCTION (__ss_accept)
        VARIABLE ptr;
	long arg0;
	int sin_size, new_fd;
        struct sockaddr_in their_addr; // connector's address information

        if(besARGNR<1) return EX_ERROR_TOO_FEW_ARGUMENTS;
        if(besARGNR>1) return EX_ERROR_TOO_MANY_ARGUMENTS;

        ptr = besARGUMENT(1);
        besDEREFERENCE(ptr);
        arg0 = besGETLONGVALUE(ptr);

        sin_size = sizeof(struct sockaddr_in);
        if ((new_fd = accept(arg0, (struct sockaddr *)&their_addr, &sin_size)) == -1) {
                printf("No connection made!\n");
                new_fd = -1;
          }
        printf("Got connection from %s\n", inet_ntoa(their_addr.sin_addr));

        besALLOC_RETURN_LONG;
        LONGVALUE(besRETURNVALUE) = new_fd;
besEND