#include <stdlib.h>
#include <unistd.h>
#include <termios.h>
#include <stdio.h>
#include <sys/select.h>

struct termios saved_tattr;

void
restore_tattr (void)
{
  if (isatty (STDIN_FILENO))
    tcsetattr (STDIN_FILENO, TCSANOW, &saved_tattr);
}

int
main (void)
{
  printf ("end with ^D\n");

  if (isatty (STDIN_FILENO)) {
    tcgetattr (STDIN_FILENO, &saved_tattr);
    struct termios tattr = saved_tattr;

    cfmakeraw(&tattr);

    tcsetattr (STDIN_FILENO, TCSAFLUSH, &tattr);
//    atexit (restore_tattr);
  }
#ifdef use_read
  setbuf (stdout, 0);
#endif

  // enable focus reporting
  printf("\e[?1004h");

  static int nread = 0;
  static unsigned char prevc = 0;

  while (1) {
    unsigned char c;
#ifdef use_read
    int n = read(0, &c, 1); if (n < 1) break;
#else
    c = getchar();
#endif

    switch (c) {
      case 0x00 ... 0x1f:
        printf ("\e[7m^%c\e[m", c + '@');
        //if (c == '\r') printf ("\r\n");
        break;
      case 0x7f:
        printf ("\e[7m^?\e[m");
        break;
      case 0x80 ... 0xFF:
        printf ("\\x%2X", c);
        break;
      default:
        putchar (c);
    }
    // count escape sequences
    if (c == '\e')
      nread++;
    // detect mangled focus report, like [[O or O[O
    if (c == '[' && prevc != '\e') {
      printf("\e[41mFAIL%4d\e[m", nread);
      // touch a marker file (and log nread in it),
      // so a test script can detect it to stop
      char s[99];
      sprintf(s, "echo failed at %d > .minstop", nread);
      system(s);
    }

    if (c == 4) {
      printf ("\r\n"); break;
    }

    prevc = c;
  }
  restore_tattr ();
  return 0;
}