/*
** a1kb.c: APPLE I Keyboard Emulator via PC LPT port
*/

#include <stdio.h>
#include <ctype.h>
#include <string.h>
#define LINUX 1
#ifdef LINUX
#include <stdlib.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <sys/io.h>
#include <termios.h>
#else
#include <conio.h>
#endif

#undef DEBUG              /* turn on to get more verbose and detailed output */

/* Width of STROBE pulse. On the Aero 4/33C, 0.1 sec for 7700 ticks */
#define DELAY 7700

#define BACKSP 0x5f
#define POS1   0x02
                
typedef unsigned char byte;
typedef unsigned int  word;

word lpt_ad = 0x378;

#ifdef LINUX
int _getch()
{
  struct termios oldt, newt;
  int ch;

  tcgetattr(STDIN_FILENO, &oldt);
  newt = oldt;
  newt.c_lflag &= ~(ICANON | ECHO);
  tcsetattr(STDIN_FILENO, TCSANOW, &newt);
  ch = getchar();
  tcsetattr(STDIN_FILENO, TCSANOW, &oldt);
  return ch;
}

int _kbhit()
{
  struct termios oldt;

  tcgetattr(0, &oldt);

  struct termios newt = oldt;

  newt.c_lflag &= ~ICANON;
  tcsetattr(0, TCSANOW, &newt);

  int byteswaiting;
  ioctl(0, FIONREAD, &byteswaiting);

  tcsetattr(0, TCSANOW, &oldt);

  return byteswaiting > 0;
}

int RD_PORT()
{
  int ch;

  /* Get access to the ports */
  if (ioperm(lpt_ad, 3, 1)) {
    perror("ioperm");
    exit(1);
  }

  ch = inb(lpt_ad);

  /* We don't need the ports anymore */
  if (ioperm(lpt_ad, 3, 0)) {
    perror("ioperm");
    exit(1);
  }

  return ch;
}

int WR_DPORT (int x)
{
  /* Get access to the ports */
  if (ioperm(lpt_ad, 3, 1)) {
    perror("ioperm");
    exit(1);
  }

  outb(x, lpt_ad);

  /* We don't need the ports anymore */
  if (ioperm(lpt_ad, 3, 0)) {
    perror("ioperm");
    exit(1);
  }
}

int WR_CPORT (int x)
{
  /* Get access to the ports */
  if (ioperm(lpt_ad, 3, 1)) {
    perror("ioperm");
    exit(1);
  }

  outb(x, lpt_ad + 2);

  /* We don't need the ports anymore */
  if (ioperm(lpt_ad, 3, 0)) {
    perror("ioperm");
    exit(1);
  }
}
#else
#define RD_DPORT()  _inp(lpt_ad)
#define WR_DPORT(x) _outp(lpt_ad, x)
#define WR_CPORT(x) _outp(lpt_ad + 2, x)
#endif

void do_cport(int idle, int active)
{
 unsigned long i;

 WR_CPORT(idle);
 for(i = 0; i < DELAY * 8l; i++) WR_CPORT(active);
 WR_CPORT(idle);
}

#ifdef LINUX
#define FILENAMLEN 16
#else
#define FILENAMLEN 128
#endif

int main(int argc, char *argv[])
{
 int i, j, key, zflg;
 FILE *fp;
 char fname[FILENAMLEN + 1];

 WR_CPORT(0x0c);
 zflg = 0;
 fp = (FILE *) 0;

 while(1) {
  if(fp) {    /* if file is open, get characters from file, not from keyboard */
   key = fgetc(fp);
   if((key == EOF) || _kbhit()) {
    fclose(fp);
    fp = (FILE *) 0;
    continue;
   }
   /* process special characters here, may end with continue */
   if(key == 0x0a) key = 0x0d;                            /* convert LF to CR */
  } else key = _getch();        /* no file open, get characters from keyboard */
  if(key) {                            /* if key code != 0, emulate key press */
   if(zflg) {               /* this <key> code had a preceeding zero key code */
    zflg = 0;
    if(key == 0x3b) { 
#ifdef DEBUG
     printf("\nF1: RESET\n");
#endif
     do_cport(0x0c, 0x08);
     continue;
    } else if(key == 0x3c) {
#ifdef DEBUG
     printf("\nF2: CLR SCREEN\n");
#endif
     do_cport(0x0c, 0x04);
     continue;
    } else if(key == 0x3d) {
     if(fp) fclose(fp);
     do {
      printf("\nEnter filename: ");
      if(!fgets(fname, FILENAMLEN, stdin)) continue;
      j = strlen(fname);
      if(fname[j - 1] == '\n') fname[--j] = '\0';
     } while(!j);
     fp = fopen(fname, "r");
     if(fp == NULL) printf("Sorry, can't open file '%s'", fname);
     putchar('\n');
     continue;
    } else if(key == 0x53) key = BACKSP;
    else if(key == 0x4b) key = POS1;
   }                        /* end of key codes with preceeding zero key code */
#ifdef DEBUG
   printf(" %.2x", key);
#endif
   if(islower(key)) key = toupper(key);
   key &= 0x7f;
#ifndef DEBUG
   putchar(key);
   if(key == 0x0d) putchar('\n');
#endif 
   WR_DPORT(key);
   key |= 0x80;
   for(i = 0; i < DELAY; i++) WR_DPORT(key);
   key &= 0x7f;
   for(j = 0; j < 10; j++) {
    for(i = 0; i < DELAY; i++) WR_DPORT(key);
    if(fp == NULL) break;
   }
  } else zflg = 1;                        /* if key code == 0, memorize this. */
 }

 exit(0);
}

/* FIN a1kb.c --------------------------------------------------------------- */