#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <fcntl.h>
#include <termios.h>
#include <errno.h>
#include <time.h>

char buf[65536];

void sendCmd(int fd, char *cmd) {
	char temp[65536];
	memcpy(temp, cmd, strlen(cmd) - 1);
	temp[strlen(cmd)-1] = 0;
	//printf("send: %s\n", temp);
	if(write(fd, cmd, strlen(cmd)) == -1) {
		fprintf(stderr, "Shit. %s\n", strerror(errno));
		exit(1);
	}
}

void recvResp(int fd) {
	int ret;

  ret = read(fd, buf, 65535);
  if(ret == -1) {
    fprintf(stderr, "Shit. %s\n", strerror(errno));
    exit(1);
  }
  if(ret > 1 && (buf[ret - 1] == '\r' || buf[ret - 2] == '\n'))
    --ret;
  if(ret > 1 && (buf[ret - 1] == '\r' || buf[ret - 2] == '\n'))
    --ret;
  buf[ret] = 0;

  if(buf[0] == '\n' || buf[0] == '\r')
    return recvResp(fd);

  //printf("recv: %s\n", buf);
}

struct termios term;
int initConn(int speed) {
	int fd = open("/dev/tty.baseband", O_RDWR | 0x20000 | O_NOCTTY);
	unsigned int blahnull = 0;
	unsigned int handshake = TIOCM_DTR | TIOCM_RTS | TIOCM_CTS | TIOCM_DSR;

	if(fd == -1) {
    fprintf(stderr, "%i(%s)\n", errno, strerror(errno));
		exit(1);
  }

	ioctl(fd, 0x2000740D);
	fcntl(fd, 4, 0);
	tcgetattr(fd, &term);
	
	ioctl(fd, 0x8004540A, &blahnull);
	cfsetspeed(&term, speed);
	cfmakeraw(&term);
	term.c_cc[VMIN] = 0;
	term.c_cc[VTIME] = 2;
	term.c_cc[VEOL] = '\r';
	
	term.c_iflag = (term.c_iflag & 0xFFFFF0CD) | 5;
	term.c_oflag =  term.c_oflag & 0xFFFFFFFE;
	term.c_cflag = (term.c_cflag & 0xFFFC6CFF) | 0x3CB00;
	term.c_lflag =  term.c_lflag & 0xFFFFFA77;

	term.c_cflag = (term.c_cflag & ~CSIZE) | CS8;
	term.c_cflag &= ~PARENB;
	term.c_lflag |= ICANON;
	term.c_lflag &= ~ECHO;
	
	tcsetattr(fd, TCSANOW, &term);

	ioctl(fd, TIOCSDTR);
	ioctl(fd, TIOCCDTR);
	ioctl(fd, TIOCMSET, &handshake);

  sendCmd(fd, "at\r");
  recvResp(fd);
  if(buf[0] != '0') {
    recvResp(fd);

    sendCmd(fd, "atv0\r");
    recvResp(fd);
    recvResp(fd);
    
    sendCmd(fd, "atE0\r");
    recvResp(fd);
    recvResp(fd);
  }
}

int main(int argc, char **argv) {
  int fd;
  
	unsigned int ctr;
	char brutebuf[28] = "AT+CLCK=\"PN\",0,\"00000000\"\r";

	time_t start, end;

  int kps, foo;
  int days, hours, secs, mins;
	
  fd = initConn(atoi(argv[2]));

  if(argc > 3) {
    sprintf(buf, "at+ipr=%s\r", argv[3]);
    sendCmd(fd, buf);
    cfsetspeed(&term, atoi(argv[3]));
    tcsetattr(fd, TCSANOW, &term);
    recvResp(fd);
    return 1;
  }

	start = time(0);

	for(ctr = atoi(argv[1]); ctr < 100000000; ++ctr) {
		if((ctr % 1000) == 0 && ctr != 0) {
			end = time(0);
      kps = 1000 / (unsigned int) difftime(end, start);
      foo = (99999999 - ctr) / kps;
      secs = foo % 60;
      mins = (foo / 60) % 60;
      hours = (foo / 60 / 60) % 24;
      days = foo / 60 / 60 / 24;
			fprintf(
              stderr, 
              "%08u -- %i kps.  Time to completion: %i:%02i:%02i:%02i\n", 
              ctr, kps, 
              days, hours, mins, secs
              );
			start = end;
		}
		sprintf(brutebuf + 16, "%08u\"\r", ctr);
		sendCmd(fd, brutebuf);
		recvResp(fd);
		if(buf[0] != '4')
			fprintf(stderr, "Last command: %s\nRecv: %s\n", brutebuf, buf, buf[0]);
	}
	close(fd);
}