/* SANE - Scanner Access Now Easy.

   Copyright (C) 2006-2007 Wittawat Yamwong <wittawat@web.de>

   This file is part of the SANE package.

   This program is free software; you can redistribute it and/or
   modify it under the terms of the GNU General Public License as
   published by the Free Software Foundation; either version 2 of the
   License, or (at your option) any later version.

   This program is distributed in the hope that it will be useful, but
   WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place - Suite 330, Boston,
   MA 02111-1307, USA.

   As a special exception, the authors of SANE give permission for
   additional uses of the libraries contained in this release of SANE.

   The exception is that, if you link a SANE library with other files
   to produce an executable, this does not by itself cause the
   resulting executable to be covered by the GNU General Public
   License.  Your use of that executable is in no way restricted on
   account of linking the SANE library code into it.

   This exception does not, however, invalidate any other reasons why
   the executable file might be covered by the GNU General Public
   License.

   If you submit changes to SANE to the maintainers to be included in
   a subsequent release, you agree by submitting the changes that
   those changes may be distributed with this exception intact.

   If you write modifications of your own for SANE, it is your choice
   whether to permit this exception to apply to your modifications.
   If you do not wish that, delete this exception notice.
 */
#include "../include/sane/config.h"

#include <string.h>
#include <stdlib.h>
#include <limits.h>		/* INT_MAX */

#include "pixma_rename.h"
#include "pixma_common.h"
#include "pixma_io.h"

#include "../include/sane/sanei_usb.h"


#ifdef __GNUC__
# define UNUSED(v) (void) v
#else
# define UNUSED(v)
#endif


struct pixma_io_t
{
  pixma_io_t *next;
  SANE_Int usb;
};

typedef struct scanner_info_t
{
  struct scanner_info_t *next;
  char *devname;
  const pixma_config_t *cfg;
  char serial[PIXMA_MAX_ID_LEN + 1];	/* "xxxxyyyy_zzzzzzz..."
					   x = vid, y = pid, z = serial */
} scanner_info_t;


static scanner_info_t *first_scanner = NULL;
static pixma_io_t *first_io = NULL;
static unsigned nscanners;


static scanner_info_t *
get_scanner_info (unsigned devnr)
{
  scanner_info_t *si;
  for (si = first_scanner; si && devnr != 0; --devnr, si = si->next)
    {
    }
  return si;
}

static SANE_Status
attach (SANE_String_Const devname)
{
  scanner_info_t *si;

  si = (scanner_info_t *) calloc (1, sizeof (*si));
  if (!si)
    return SANE_STATUS_NO_MEM;
  si->devname = strdup (devname);
  if (!si->devname)
    return SANE_STATUS_NO_MEM;
  si->next = first_scanner;
  first_scanner = si;
  nscanners++;
  return SANE_STATUS_GOOD;
}

static void
clear_scanner_list (void)
{
  scanner_info_t *si = first_scanner;
  while (si)
    {
      scanner_info_t *temp = si;
      free (si->devname);
      si = si->next;
      free (temp);
    }
  nscanners = 0;
  first_scanner = NULL;
}

static SANE_Status
get_descriptor (SANE_Int dn, SANE_Int type, SANE_Int descidx,
		SANE_Int index, SANE_Int length, SANE_Byte * data)
{
  return sanei_usb_control_msg (dn, 0x80, USB_REQ_GET_DESCRIPTOR,
				((type & 0xff) << 8) | (descidx & 0xff),
				index, length, data);
}

static SANE_Status
get_string_descriptor (SANE_Int dn, SANE_Int index, SANE_Int lang,
		       SANE_Int length, SANE_Byte * data)
{
  return get_descriptor (dn, USB_DT_STRING, index, lang, length, data);
}

static void
u16tohex (uint16_t x, char *str)
{
  static const char hdigit[16] =
    { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D',
'E', 'F' };
  str[0] = hdigit[(x >> 12) & 0xf];
  str[1] = hdigit[(x >> 8) & 0xf];
  str[2] = hdigit[(x >> 4) & 0xf];
  str[3] = hdigit[x & 0xf];
  str[4] = '\0';
}

static void
read_serial_number (scanner_info_t * si)
{
  uint8_t unicode[2 * (PIXMA_MAX_ID_LEN - 9) + 2];
  uint8_t ddesc[18];
  int i, len, iSerialNumber;
  SANE_Int usb;
  SANE_Status status;
  char *serial = si->serial;

  u16tohex (si->cfg->vid, serial);
  u16tohex (si->cfg->pid, serial + 4);

  if (SANE_STATUS_GOOD != sanei_usb_open (si->devname, &usb))
    return;
  if (get_descriptor (usb, USB_DT_DEVICE, 0, 0, 18, ddesc)
      != SANE_STATUS_GOOD)
    goto done;
  iSerialNumber = ddesc[16];
  if (iSerialNumber != 0)
    {
      int iSerialNumber = ddesc[16];
      /* Read the first language code. Assumed that there is at least one. */
      if (get_string_descriptor (usb, 0, 0, 4, unicode) != SANE_STATUS_GOOD)
	goto done;
      /* Read the serial number string. */
      status =
	get_string_descriptor (usb, iSerialNumber,
			       unicode[3] * 256 + unicode[2],
			       sizeof (unicode), unicode);
      if (status != SANE_STATUS_GOOD)
	goto done;
      /* Assumed charset: Latin1 */
      len = unicode[0];
      if (len > (int) sizeof (unicode))
	{
	  len = sizeof (unicode);
	  PDBG (pixma_dbg (1, "WARNING:Truncated serial number\n"));
	}
      serial[8] = '_';
      for (i = 2; i < len; i += 2)
	{
	  serial[9 + i / 2 - 1] = unicode[i];
	}
      serial[9 + i / 2 - 1] = '\0';
    }
  else
    {
      PDBG (pixma_dbg (1, "WARNING:No serial number\n"));
    }
done:
  sanei_usb_close (usb);
}

static int
map_error (SANE_Status ss)
{
  switch (ss)
    {
    case SANE_STATUS_GOOD:
      return 0;
    case SANE_STATUS_UNSUPPORTED:
      return PIXMA_ENODEV;
    case SANE_STATUS_DEVICE_BUSY:
      return PIXMA_EBUSY;
    case SANE_STATUS_INVAL:
      return PIXMA_EINVAL;
    case SANE_STATUS_IO_ERROR:
      return PIXMA_EIO;
    case SANE_STATUS_NO_MEM:
      return PIXMA_ENOMEM;
    case SANE_STATUS_ACCESS_DENIED:
      return PIXMA_EACCES;
    case SANE_STATUS_CANCELLED:
    case SANE_STATUS_EOF:
    case SANE_STATUS_JAMMED:
    case SANE_STATUS_NO_DOCS:
    case SANE_STATUS_COVER_OPEN:
      break;
    }
  PDBG (pixma_dbg (1, "BUG:Unmapped SANE Status code %d\n", ss));
  return PIXMA_EIO;		/* should not happen */
}


int
pixma_io_init (void)
{
  sanei_usb_init ();
  nscanners = 0;
  return 0;
}

void
pixma_io_cleanup (void)
{
  while (first_io)
    pixma_disconnect (first_io);
  clear_scanner_list ();
}

unsigned
pixma_collect_devices (const struct pixma_config_t *const pixma_devices[])
{
  unsigned i, j;
  scanner_info_t *si;
  const pixma_config_t *cfg;

  clear_scanner_list ();
  j = 0;
  for (i = 0; pixma_devices[i]; i++)
    {
      for (cfg = pixma_devices[i]; cfg->name; cfg++)
	{
	  sanei_usb_find_devices (cfg->vid, cfg->pid, attach);
	  si = first_scanner;
	  while (j < nscanners)
	    {
	      PDBG (pixma_dbg (3, "pixma_collect_devices() found %s at %s\n",
			       cfg->name, si->devname));
	      si->cfg = cfg;
	      read_serial_number (si);
	      si = si->next;
	      j++;
	    }
	}
    }
  return nscanners;
}

const pixma_config_t *
pixma_get_device_config (unsigned devnr)
{
  const scanner_info_t *si = get_scanner_info (devnr);
  return (si) ? si->cfg : NULL;
}

const char *
pixma_get_device_id (unsigned devnr)
{
  const scanner_info_t *si = get_scanner_info (devnr);
  return (si) ? si->serial : NULL;
}

int
pixma_connect (unsigned devnr, pixma_io_t ** handle)
{
  pixma_io_t *io;
  SANE_Int usb;
  const scanner_info_t *si;
  int error;

  *handle = NULL;
  si = get_scanner_info (devnr);
  if (!si)
    return PIXMA_EINVAL;
  error = map_error (sanei_usb_open (si->devname, &usb));
  if (error < 0)
    return error;
  io = (pixma_io_t *) calloc (1, sizeof (*io));
  if (!io)
    {
      sanei_usb_close (usb);
      return PIXMA_ENOMEM;
    }
  io->next = first_io;
  first_io = io;
  io->usb = usb;
  *handle = io;
  return 0;
}


void
pixma_disconnect (pixma_io_t * io)
{
  pixma_io_t **p;

  if (!io)
    return;
  for (p = &first_io; *p && *p != io; p = &((*p)->next))
    {
    }
  PASSERT (*p);
  if (!(*p))
    return;
  sanei_usb_close (io->usb);
  *p = io->next;
  free (io);
}

int
pixma_reset_device (pixma_io_t * io)
{
  UNUSED (io);
  return PIXMA_ENOTSUP;
}

int
pixma_write (pixma_io_t * io, const void *cmd, unsigned len)
{
  size_t count = len;
  int error;

#ifdef HAVE_SANEI_USB_SET_TIMEOUT
  sanei_usb_set_timeout (PIXMA_BULKOUT_TIMEOUT);
#endif
  error = map_error (sanei_usb_write_bulk (io->usb, cmd, &count));
  if (error == PIXMA_EIO)
    error = PIXMA_ETIMEDOUT;	/* FIXME: SANE doesn't have ETIMEDOUT!! */
  if (count != len)
    {
      PDBG (pixma_dbg (1, "WARNING:pixma_write(): count(%u) != len(%u)\n",
		       (unsigned) count, len));
      error = PIXMA_EIO;
    }
  if (error >= 0)
    error = count;
  PDBG (pixma_dump (10, "OUT ", cmd, error, len, 128));
  return error;
}

int
pixma_read (pixma_io_t * io, void *buf, unsigned size)
{
  size_t count = size;
  int error;

#ifdef HAVE_SANEI_USB_SET_TIMEOUT
  sanei_usb_set_timeout (PIXMA_BULKIN_TIMEOUT);
#endif
  error = map_error (sanei_usb_read_bulk (io->usb, buf, &count));
  if (error == PIXMA_EIO)
    error = PIXMA_ETIMEDOUT;	/* FIXME: SANE doesn't have ETIMEDOUT!! */
  if (error >= 0)
    error = count;
  PDBG (pixma_dump (10, "IN  ", buf, error, -1, 128));
  return error;
}

int
pixma_wait_interrupt (pixma_io_t * io, void *buf, unsigned size, int timeout)
{
  size_t count = size;
  int error;

#ifdef HAVE_SANEI_USB_SET_TIMEOUT
  /* FIXME: What is the meaning of "timeout" in sanei_usb? */
  if (timeout < 0)
    timeout = INT_MAX;
  else if (timeout < 10)
    timeout = 10;
  sanei_usb_set_timeout (timeout);
#endif
  error = map_error (sanei_usb_read_int (io->usb, buf, &count));
  if (error == PIXMA_EIO)
    error = PIXMA_ETIMEDOUT;	/* FIXME: SANE doesn't have ETIMEDOUT!! */
  if (error == 0)
    error = count;
  if (error != PIXMA_ETIMEDOUT)
    PDBG (pixma_dump (10, "INTR", buf, error, -1, -1));
  return error;
}

int
pixma_set_interrupt_mode (pixma_io_t * s, int background)
{
  UNUSED (s);
  return (background) ? PIXMA_ENOTSUP : 0;
}