/* This file is in the public domain. */

#include <stdio.h>
#include <fcntl.h>
#include <ctype.h>
#include <errno.h>
#include <stdarg.h>
#include <stdlib.h>
#include <unistd.h>
#include <strings.h>
#include <termios.h>

extern const char *__progname;

#include "errf.h"
#include "panic.h"
#include "config.h"
#include "nested.h"
#include "escaped.h"
#include "stdio-util.h"

#include "interact.h"

static int pp_initted = 0;
static int pp_ifd;
static int pp_ofd;
static int tio_saved;
static int flags_saved;
#define SAVE_FLAGS (O_NONBLOCK)
static struct termios tio_old;
static struct termios tio_new;

static void get_pp_fds(void)
{
 if (! pp_initted)
  { pp_ifd = open("/dev/tty",O_RDWR,0);
    if (pp_ifd < 0)
     { pp_ifd = 0;
       pp_ofd = 1;
     }
    else
     { pp_ofd = pp_ifd;
     }
    pp_initted = 1;
  }
}

static void save_tio(int fd)
{
 tio_saved = (tcgetattr(fd,&tio_old) >= 0);
 flags_saved = fcntl(fd,F_GETFL,0) & SAVE_FLAGS;
}

static void restore_tio(int fd)
{
 tcsetattr(fd,TCSANOW,&tio_old);
 fcntl(fd,F_SETFL,(fcntl(fd,F_GETFL,0)&~SAVE_FLAGS)|flags_saved);
}

static void echo_off(int fd)
{
 if (tio_saved)
  { tio_new = tio_old;
    tio_new.c_lflag &= ~(ECHO|ECHOK|ECHOE|ECHOKE|ECHOPRT|ECHOCTL);
    if (tio_old.c_lflag & ECHO) tio_new.c_lflag |= ECHONL;
    tcsetattr(fd,TCSANOW,&tio_new);
  }
}

static void nbio_off(int fd)
{
 fcntl(fd,F_SETFL,fcntl(fd,F_GETFL,0)&~O_NONBLOCK);
}

static void prompt(int to, const char *fmt, va_list ap)
{
 FILE *f;

 NESTED int w(void *cookie __attribute__((__unused__)), const char *buf, int len)
  { return(write(to,buf,len));
  }

 f = fwopen(0,w);
 vfprintf(f,fmt,ap);
 fclose(f);
}

void get_with_prompt(char **sp, int *lp, unsigned int flags, const char *fmt, ...)
{
 va_list ap;
 FILE *f;
 int r;
 char c;
 int ifd;
 int ofd;
 int eofs;

 if (config_bool("no-interaction")) panic("not interactive");
 if (flags & GWP_DEV_TTY)
  { get_pp_fds();
    ifd = pp_ifd;
    ofd = pp_ofd;
  }
 else
  { ifd = 0;
    ofd = 1;
  }
 save_tio(ifd);
 if (flags & GWP_NO_ECHO) echo_off(ifd);
 nbio_off(ifd);
 if (flags & GWP_ESC_BLK)
  { int len;
    NESTED int w(void *cookie __attribute__((__unused__)), const char *buf, int len)
     { return(write(ofd,buf,len));
     }
    f = fwopen(0,&w);
    va_start(ap,fmt);
    len = va_arg(ap,int);
    va_end(ap);
    print_escaped(f,fmt,len,len);
    fclose(f);
  }
 else
  { va_start(ap,fmt);
    prompt(ofd,fmt,ap);
    va_end(ap);
  }
 f = fopen_alloc(sp,lp);
 eofs = 0;
 while (1)
  { r = read(ifd,&c,1);
    switch (r)
     { case -1:
	  switch (errno)
	   { case EINTR:
		continue;
		break;
	     default:
		fprintf(errf,"%s: read: %s\n",__progname,strerror(errno));
		exit(1);
		break;
	   }
	  break;
       case 0:
	  fprintf(errf,"%s: read EOF\n",__progname);
	  if (eofs++ > 20) exit(1);
	  break;
       case 1:
	  if (eofs) eofs --;
	  break;
       default:
	  fprintf(errf,"%s: read returned %d?\n",__progname,r);
	  exit(1);
	  break;
     }
    if ((c == '\n') || (c == '\r'))
     { fclose(f);
       restore_tio(ifd);
       return;
     }
    putc(c,f);
  }
}

int prompted_choice(const char *prompt, int nresp, ...)
{
 va_list ap;
 const char **resps;
 int *lens;
 int i;
 char *resp;
 int rlen;
 int s;

 if (config_bool("no-interaction")) panic("not interactive");
 resps = malloc(nresp*sizeof(const char *));
 lens = malloc(nresp*sizeof(int));
 va_start(ap,nresp);
 for (i=0;i<nresp;i++)
  { resps[i] = va_arg(ap,const char *);
    lens[i] = strlen(resps[i]);
  }
 va_end(ap);
 while <"done"> (1)
  { get_with_prompt(&resp,&rlen,GWP_DEV_TTY,"%s",prompt);
    while ((rlen > 0) && isspace((unsigned char)resp[rlen-1])) rlen --;
    if (rlen < 1) continue;
    for (s=0;(s<rlen)&&isspace((unsigned char)resp[s]);s++) ;
    for (i=0;i<nresp;i++)
     { if ((rlen-s == lens[i]) && !bcmp(resps[i],resp+s,lens[i]))
	{ free(resp);
	  free(lens);
	  free(resps);
	  return(i);
	}
     }
    free(resp);
  }
}