#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <termios.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <sys/time.h>
#include <sys/ioctl.h>
#include <signal.h>
#include <sys/io.h>


#define BAUDRATE B19200


int main(int *argc, char **argv){
        printf("Sending sms...\n");
        printf("%d\n",argc);
        if (argc <5 ) {
                printf("Usage %s port_speed device_name phone_num message\n",argv[0]);
                return -1;
        }


        int fd;
        char buf[256] , res[256];
        size_t nbytes;
        struct termios oldtio,newtio;


        printf("port speed -> %s, device -> %s, phone_num -> %s, message -> %s\n",argv[1],argv[2],argv[3],argv[4]);
        //fd = open(argv[2], O_RDWR | O_NOCTTY | O_NONBLOCK);
        fd = open(argv[2], O_RDWR | O_NOCTTY);
        if (fd == -1) { perror("Error opening port"); }
        tcgetattr(fd,&oldtio); /* save current serial port settings */
        bzero(&newtio, sizeof(newtio)); /* clear struct for new port settings */
       /* 
          BAUDRATE: Set bps rate. You could also use cfsetispeed and cfsetospeed.
          CRTSCTS : output hardware flow control (only used if the cable has
                    all necessary lines. See sect. 7 of Serial-HOWTO)
          CS8     : 8n1 (8bit,no parity,1 stopbit)
          CLOCAL  : local connection, no modem contol
          CREAD   : enable receiving characters
        */
         newtio.c_cflag = BAUDRATE | CRTSCTS | CS8 | CLOCAL | CREAD;
        //newtio.c_cflag = BAUDRATE | CS8 | CLOCAL | CREAD;
         
        /*
          IGNPAR  : ignore bytes with parity errors
          ICRNL   : map CR to NL (otherwise a CR input on the other computer
                    will not terminate input)
          otherwise make device raw (no other input processing)
        */
         newtio.c_iflag = IGNPAR | ICRNL;
         
        /*
         Raw output.
        */
         newtio.c_oflag = 0;
         
        /*
          ICANON  : enable canonical input
          disable all echo functionality, and don't send signals to calling program
        */
         newtio.c_lflag = ICANON;
         
        /* 
          now clean the modem line and activate the settings for the port
        */
        int fdFlags;
        fcntl(fd, F_SETFL, fdFlags);
        fdFlags &= ~O_NONBLOCK;
        fcntl(fd, F_SETFL, fdFlags);
        tcflush(fd, TCOFLUSH);
        // toggle DTR to reset modem
        int mctl = TIOCM_DTR;
        ioctl(fd, TIOCMBIC, &mctl);

         tcflush(fd, TCIFLUSH);
         tcsetattr(fd,TCSANOW,&newtio);
        

/* logics here */

        //printf("%d\n",sizeof(buf));
        //memset(buf, 0, sizeof(buf));
        //strcpy(buf,"ATZ");
        //write(fd,buf,strlen(buf));
        //sleep(13);
        fd_set fds;
        struct timeval timeout;
        FD_ZERO(&fds);
        FD_SET(fd, &fds);
        timeout.tv_sec = 50;
        timeout.tv_usec = 0;
        //select(FD_SETSIZE, &fds, NULL, NULL, &timeout);
        select(FD_SETSIZE, NULL, &fds, NULL, &timeout);
        //strcpy(buf,"AT S7=45 S0=0 L1 V1 X4 &c1 E1 Q0");
        strcpy(buf,"ATZ\r");
        printf("say -> %s\n",buf);
        write(fd,buf,strlen(buf));
        FD_ZERO(&fds);
        FD_SET(fd, &fds);
        select(FD_SETSIZE, &fds, NULL, NULL, &timeout);
        read(fd,res,255); //read "OK"
        printf("got response <- %s\n",res);
        FD_ZERO(&fds);
        FD_SET(fd, &fds);
        select(FD_SETSIZE, NULL, &fds, NULL, &timeout);
        strcpy(buf,"AT+CMGF=1\r");
        printf("say -> %s\n",buf);
        write(fd,buf,strlen(buf));
        memset(res, 0, sizeof(res));
        //sleep(3);
        FD_ZERO(&fds);
        FD_SET(fd, &fds);
        select(FD_SETSIZE, &fds, NULL, NULL, &timeout);
        read(fd,res,255); //read "OK"
        printf("got response <- %s\n",res);
        memset(buf, 0, sizeof(buf));
        strcpy(buf,"AT+CMGW=\"");
        strcpy(buf+strlen(buf),argv[3]);
        strcpy(buf+strlen(buf),"\"\r");
        printf("say -> %s\n",buf);
        FD_ZERO(&fds);
        FD_SET(fd, &fds);
        select(FD_SETSIZE, NULL, &fds, NULL, &timeout);
        write(fd,buf,strlen(buf));
        memset(res, 0, sizeof(res));
        //FD_ZERO(&fds);
        //FD_SET(fd, &fds);
        //select(FD_SETSIZE, &fds, NULL, NULL, &timeout);
        //read(fd,res,255); //read  ">"
        //printf("got response <- %s\n",res);
        memset(buf, 0, sizeof(buf));
        strcpy(buf,argv[4]);
        strcpy(buf+strlen(buf),"\032");
        printf("sending payload %s\n",buf);
        FD_ZERO(&fds);
        FD_SET(fd, &fds);
        select(FD_SETSIZE, NULL, &fds, NULL, &timeout);
        write(fd,buf,strlen(buf)); //write message to
        //sleep(5); //sleep after send
        memset(buf, 0, sizeof(buf));
        FD_ZERO(&fds);
        FD_SET(fd, &fds);
        select(FD_SETSIZE, &fds, NULL, NULL, &timeout);
        read(fd,buf,255); //read response "+CMGW: ID"
        printf("got response <- %s\n",buf);

        memset(buf, 0, sizeof(buf));
        while (strstr(buf,"CMGW:")==NULL){
        memset(buf, 0, sizeof(buf));
        FD_ZERO(&fds);
        FD_SET(fd, &fds);
        select(FD_SETSIZE, &fds, NULL, NULL, &timeout);
        read(fd,buf,255); //read response "+CMGW: ID"
        printf("got response <- %s\n",buf);
        }




        memset(res, 0, sizeof(res));
        strncpy(res,strchr(buf,' ')+1,(strlen(strchr(buf,' ')+1))); //searching for sms ID
        printf("got sms ID number -- %s\n",res);
        memset(buf, 0, sizeof(buf));
        strcpy(buf,"AT+CMSS=");
        strncpy(buf+strlen(buf),res,strlen(res));
        strcpy(buf+strlen(buf),"\r");
        FD_ZERO(&fds);
        FD_SET(fd, &fds);
        select(FD_SETSIZE, NULL, &fds, NULL, &timeout);
        write(fd,buf,strlen(buf));
        memset(buf, 0, sizeof(buf));
        FD_ZERO(&fds);
        FD_SET(fd, &fds);
        select(FD_SETSIZE, &fds, NULL, NULL, &timeout);
        read(fd,buf,255); //read
        printf("got response <- %s\n",buf);
        memset(res, 0, sizeof(res));
        strncpy(res,strchr(buf,' ')+1,(strlen(strchr(buf,' ')+1))); //searching for _sent_ sms ID
        printf("got _sent_ sms ID %s\n",res);


        //read +CMSS: 218
        //deleteting stored sms (but how?)




         /* restore the old port settings */
         tcsetattr(fd,TCSANOW,&oldtio);
        return 0;
}