/* GNU Mailutils -- a suite of utilities for electronic mail
   Copyright (C) 1999, 2000, 2001, 2004, 2005, 2007  Free Software Foundation, Inc.

   This library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 3 of the License, or (at your option) any later version.

   This library 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
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General
   Public License along with this library; if not, write to the
   Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
   Boston, MA 02110-1301 USA */

#ifdef HAVE_CONFIG_H
# include <config.h>
#endif

#include <errno.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>

#include <mailutils/errno.h>
#include <mailutils/nls.h>
#include <debug0.h>

mu_debug_printer_fp mu_debug_default_printer = mu_debug_stderr_printer;

int
mu_debug_create (mu_debug_t *pdebug, void *owner)
{
  mu_debug_t debug;
  if (pdebug == NULL)
    return MU_ERR_OUT_PTR_NULL;
  debug = calloc (sizeof (*debug), 1);
  if (debug == NULL)
    return ENOMEM;
  debug->printer = mu_debug_default_printer;
  debug->owner = owner;
  *pdebug = debug;
  return 0;
}

void
mu_debug_destroy (mu_debug_t *pdebug, void *owner)
{
  if (pdebug && *pdebug)
    {
      mu_debug_t debug = *pdebug;
      if (debug->owner == owner)
	{
	  mu_stream_destroy (&debug->stream,
			     mu_stream_get_owner (debug->stream));
	  free (*pdebug);
	  *pdebug = NULL;
	}
    }
}

void *
mu_debug_get_owner (mu_debug_t debug)
{
  return (debug) ? debug->owner : NULL;
}

int
mu_debug_set_level (mu_debug_t debug, size_t level)
{
  if (debug == NULL)
    return EINVAL;
  debug->level = level;
  return 0;
}

int
mu_debug_get_level (mu_debug_t debug, size_t *plevel)
{
  if (debug == NULL)
    return EINVAL;
  if (plevel)
    *plevel = debug->level;
  return 0;
}

int
mu_debug_set_print (mu_debug_t debug, mu_debug_printer_fp printer, void *owner)
{
  if (debug == NULL)
    return EINVAL;
  if (debug->owner != owner)
    return EACCES;
  debug->printer = printer;
  return 0;
}

int
mu_debug_print (mu_debug_t debug, size_t level, const char *format, ...)
{
  va_list ap;

  va_start (ap, format);
  
  mu_debug_printv (debug, level, format, ap);
  
  va_end (ap);

  return 0;
}

int
mu_debug_printv (mu_debug_t debug, size_t level, const char *format,
		 va_list ap)
{
  if (debug == NULL || format == NULL)
    return EINVAL;

  if (!(debug->level & level))
    return 0;

  if (debug->printer)
    {
      mu_off_t len;
      mu_transport_t tbuf;
      char *ptr, *start, *p;
      size_t nseg;
      
      if (debug->stream == NULL)
	{
	  int rc = mu_memory_stream_create (&debug->stream, NULL, 0);
	  if (rc)
	    {
	      fprintf (stderr,
		       _("cannot create memory stream for debugging output: %s\n"),
		       mu_strerror (rc));
	      vfprintf (stderr, format, ap);
	      return rc;
	    }
	}

      mu_stream_sequential_vprintf (debug->stream, format, ap);
      mu_stream_get_transport (debug->stream, &tbuf);
      start = (char*) tbuf;
      mu_stream_size (debug->stream, &len);
      ptr = start;
      nseg = 0;
      for (p = ptr = start; p < start + len; p++)
	{
	  if (*p == '\n')
	    {
	      int c = *++p;
	      *p = 0;
	      debug->printer (debug, level, ptr);
	      *p = c;
	      ptr = p;
	      nseg++;
	    }
	}

      if (nseg)
	{
	  if (start[len - 1] != '\n')
	    {
	      size_t s = len - (ptr - start);
	      memmove (start, ptr, len);
	    }
	  else
	    len = 0;

	  mu_stream_truncate (debug->stream, len);
	  mu_stream_seek (debug->stream, len, SEEK_SET);
	}
    }
  else
    vfprintf (stderr, format, ap);

  return 0;
}