/******************************************************
 *
 * zexy - implementation file
 *
 * copyleft (c) IOhannes m zmölnig
 *
 *   1999:forum::für::umläute:2004
 *
 *   institute of electronic music and acoustics (iem)
 *
 ******************************************************
 *
 * license: GNU General Public License v.2
 *
 ******************************************************/

/* 
   (c) 2000:forum::für::umläute:2004

   write to the parallel port
   extended to write to any port (if we do have permissions)

   thanks to
    Olaf Matthes: porting to WindozeNT/2000/XP
    Thomas Musil: adding "control-output" and "input"
*/

#define BASE0  0x3bc
#define BASE1  0x378
#define BASE2  0x278

#define MODE_IOPERM 1
#define MODE_IOPL   0
#define MODE_NONE   -1

#include "zexy.h"

/* ----------------------- lpt --------------------- */

#ifdef Z_WANT_LPT
# include <stdlib.h>

# ifdef NT
/* on windoze everything is so complicated... */
extern int read_parport(int port);
extern void write_parport(int port, int value);
extern int open_port(int port);

static int ioperm(int port, int a, int b)
{
  if(open_port(port) == -1)return(1);
  return(0);
}

static int iopl(int i)
{
  return(-1);
}

static void sys_outb(unsigned char byte, int port)
{
  write_parport(port, byte);
}
static int sys_inb(int port)
{
  return read_parport(port);
}
# else
/* thankfully there is linux */
#  include <sys/io.h>

static void sys_outb(unsigned char byte, int port)
{
  outb(byte, port);
}
static int sys_inb(int port)
{
  return inb(port);
}
# endif /* NT */
#endif /* Z_WANT_LP */


static int count_iopl = 0;
static t_class *lpt_class;

typedef struct _lpt
{
  t_object x_obj;

  unsigned long port;

  int mode; // MODE_IOPERM, MODE_IOPL
} t_lpt;

static void lpt_float(t_lpt *x, t_floatarg f)
{
#ifdef Z_WANT_LPT
  if (x->port) {
    unsigned char b = f;
    sys_outb(b, x->port+0);
  }
#endif /*  Z_WANT_LPT */
}

static void lpt_control(t_lpt *x, t_floatarg f)
{
#ifdef Z_WANT_LPT
  if (x->port) {
    unsigned char b = f;
    sys_outb(b, x->port+2);
  }
#endif /*  Z_WANT_LPT */
}

static void lpt_bang(t_lpt *x)
{
#ifdef Z_WANT_LPT
  if (x->port)	{
    outlet_float(x->x_obj.ob_outlet, (float)sys_inb(x->port+1));
  }
#endif /*  Z_WANT_LPT */
}


static void *lpt_new(t_symbol *s, int argc, t_atom *argv)
{
  t_lpt *x = (t_lpt *)pd_new(lpt_class);
  if(s==gensym("lp"))
    error("lpt: the use of 'lp' has been deprecated; use 'lpt' instead");

  inlet_new(&x->x_obj, &x->x_obj.ob_pd, gensym("float"), gensym("control"));
  outlet_new(&x->x_obj, gensym("float"));
  x->mode = MODE_NONE;
  x->port = 0;

#ifdef Z_WANT_LPT
 
  if ((argc==0)||(argv->a_type==A_FLOAT)) {
    /* FLOAT specifies a parallel port */
    switch ((int)((argc)?atom_getfloat(argv):0)) {
    case 0:
      x->port = BASE0;
      break;
    case 1:
      x->port = BASE1;
      break;  
    case 2:
      x->port = BASE2;
      break;
    default:
      error("lpt : only lpt0, lpt1 and lpt2 are accessible");
      x->port = 0;
      return (x);
    }
  } else { 
    /* SYMBOL might be a file or a hex port-number;
       we ignore the file (device) case by now;
       LATER think about this
    */
    x->port=strtol(atom_getsymbol(argv)->s_name, 0, 16);
  }

  if (!x->port || x->port>65535){
    post("lpt : bad port %x", x->port);
    x->port = 0;
    return (x);
  }

  if (x->port && x->port < 0x400){
    if (ioperm(x->port, 8, 1)) {
      x->mode=MODE_NONE;
    } else x->mode = MODE_IOPERM;
  }
  if(x->mode==MODE_NONE){
    if (iopl(3)){
      x->mode=MODE_NONE;
    } else x->mode=MODE_IOPL;
    count_iopl++;
    //    post("iopl.............................%d", count_iopl);
  }
  
  if(x->mode==MODE_NONE){
    error("lpt : couldn't get write permissions");
    x->port = 0;
    return (x);
  }
  
  post("connected to port %x in mode '%s'", x->port, (x->mode==MODE_IOPL)?"iopl":"ioperm");
  if (x->mode==MODE_IOPL)post("warning: this might seriously damage your pc...");
#else
  error("zexy has been compiled without [lpt]!");
#endif /* Z_WANT_LPT */

  return (x);
}

static void lpt_free(t_lpt *x)
{
#ifdef Z_WANT_LPT
  if (x->port) {
    if (x->mode==MODE_IOPERM && ioperm(x->port, 8, 0)) error("lpt: couldn't clean up device");
    else if (x->mode==MODE_IOPL && (!--count_iopl) && iopl(0))
      error("lpt: couldn't clean up device");
  }
#endif /* Z_WANT_LPT */
}


static void helper(t_lpt *x)
{
  post("\n%c lpt :: direct access to the parallel port", HEARTSYMBOL);
  post("<byte>\t: write byte to the parallel-port");
  post("\ncreation:\t\"lpt [<port>]\": connect to parallel port <port> (0..2)");
  post("\t\t\"lpt <portaddr>\": connect to port @ <portaddr> (hex)");
}

void lpt_setup(void)
{
  lpt_class = class_new(gensym("lpt"),
			  (t_newmethod)lpt_new, (t_method)lpt_free,
			  sizeof(t_lpt), 0, A_GIMME, 0);
  class_addcreator((t_newmethod)lpt_new, gensym("lp"), A_GIMME, 0);

  class_addfloat(lpt_class, (t_method)lpt_float);
  class_addmethod(lpt_class, (t_method)lpt_control, gensym("control"), A_FLOAT, 0);
  class_addbang(lpt_class, (t_method)lpt_bang);

  class_addmethod(lpt_class, (t_method)helper, gensym("help"), 0);
  class_sethelpsymbol(lpt_class, gensym("zexy/lpt"));
  zexy_register("lpt");
}