/* The GIMP -- an image manipulation program
 * Copyright (C) 1995 Spencer Kimball and Peter Mattis
 * Copyright (C) 1997 Daniel Risacher, magnus@alum.mit.edu
 *
 * 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.
 */

/* Minor changes to support file magic */
/* 4 Oct 1997 -- Risacher */

/* gzip plug-in for the gimp */
/* loosley based on url.c by */
/* Josh MacDonald, jmacd@cs.berkeley.edu */

/* and, very loosely on hrz.c by */
/* Albert Cahalan <acahalan at cs.uml.edu> */

/* This is reads and writes gziped image files for the Gimp
 *
 * You need to have gzip installed for it to work.
 *
 * It should work with file names of the form
 * filename.foo.gz where foo is some already-recognized extension
 *
 * and it also works for names of the form
 * filename.xcfgz - which is equivalent to
 * filename.xcf.gz
 *
 * I added the xcfgz bit because having a default extension of xcf.gz
 * can confuse the file selection dialog box somewhat, forcing the
 * user to type sometimes when he/she otherwise wouldn't need to.
 *
 * I later decided I didn't like it because I don't like to bloat
 * the file-extension namespace.  But I left in the recognition
 * feature/bug so if people want to use files named foo.xcfgz by
 * default, they can just hack their pluginrc file.
 *
 * to do this hack, change :
 *                      "xcf.gz,gz,xcfgz"
 * to
 *                      "xcfgz,gz,xcf.gz"
 *
 *
 * -Dan Risacher, 0430 CDT, 26 May 1997
 */

#include "config.h"

#include <glib.h>		/* For G_OS_WIN32 */

#ifdef G_OS_WIN32
#define STRICT
#define WinMain WinMain_foo
#include <windows.h>
#undef WinMain
#endif

#include <stdlib.h>
#include <stdio.h>
#include <sys/types.h>
#ifdef HAVE_SYS_PARAM_H
#include <sys/param.h>
#endif
#ifdef HAVE_SYS_WAIT_H
#include <sys/wait.h>
#endif
#include <sys/stat.h>
#include <string.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <errno.h>

#ifdef __EMX__
#include <fcntl.h>
#include <process.h>
#endif

#include <libgimp/gimp.h>

#include "libgimp/stdplugins-intl.h"


/* Author 1: Josh MacDonald (url.c) */
/* Author 2: Daniel Risacher (gz.c) */

/* According to USAF Lt Steve Werhle, US DoD software development
 * contracts average about $25 USD per source line of code (SLOC).  By
 * that metric, I figure this plug-in is worth about $10,000 USD */
/* But you got it free.   Magic of Gnu. */


static void          query       (void);
static void          run         (gchar       *name,
				  gint         nparams,
				  GParam      *param,
				  gint        *nreturn_vals,
				  GParam     **return_vals);

static gint32        load_image  (gchar       *filename,
				  gint32       run_mode,
				  GStatusType *status /* return value */);
static GStatusType   save_image  (gchar       *filename,
				  gint32       image_ID,
				  gint32       drawable_ID,
				  gint32       run_mode);

static gboolean   valid_file     (gchar       *filename);
static gchar    * find_extension (gchar       *filename);

GPlugInInfo PLUG_IN_INFO =
{
  NULL,  /* init_proc  */
  NULL,  /* quit_proc  */
  query, /* query_proc */
  run,   /* run_proc   */
};

MAIN ()

static void
query (void)
{
  static GParamDef load_args[] =
  {
    { PARAM_INT32, "run_mode", "Interactive, non-interactive" },
    { PARAM_STRING, "filename", "The name of the file to load" },
    { PARAM_STRING, "raw_filename", "The name entered" },
  };
  static GParamDef load_return_vals[] =
  {
    { PARAM_IMAGE, "image", "Output image" },
  };
  static gint nload_args = sizeof (load_args) / sizeof (load_args[0]);
  static gint nload_return_vals = (sizeof (load_return_vals) /
				   sizeof (load_return_vals[0]));

  static GParamDef save_args[] =
  {
    { PARAM_INT32, "run_mode", "Interactive, non-interactive" },
    { PARAM_IMAGE, "image", "Input image" },
    { PARAM_DRAWABLE, "drawable", "Drawable to save" },
    { PARAM_STRING, "filename", "The name of the file to save the image in" },
    { PARAM_STRING, "raw_filename", "The name of the file to save the image in" }
  };
  static gint nsave_args = sizeof (save_args) / sizeof (save_args[0]);

  INIT_I18N();

  gimp_install_procedure ("file_gz_load",
                          "loads files compressed with gzip",
                          "You need to have gzip installed.",
                          "Daniel Risacher",
                          "Daniel Risacher, Spencer Kimball and Peter Mattis",
                          "1995-1997",
                          "<Load>/gzip",
			  NULL,
                          PROC_PLUG_IN,
                          nload_args, nload_return_vals,
                          load_args, load_return_vals);

  gimp_install_procedure ("file_gz_save",
                          "saves files compressed with gzip",
                          "You need to have gzip installed.",
                          "Daniel Risacher",
                          "Daniel Risacher, Spencer Kimball and Peter Mattis",
                          "1995-1997",
                          "<Save>/gzip",
			  "RGB*, GRAY*, INDEXED*",
                          PROC_PLUG_IN,
                          nsave_args, 0,
                          save_args, NULL);

  gimp_register_magic_load_handler ("file_gz_load",
				    "xcf.gz,gz,xcfgz", 
				    "",
				    "0,string,\037\213");
  gimp_register_save_handler       ("file_gz_save",
				    "xcf.gz,gz,xcfgz",
				    "");
}

static void
run (gchar   *name,
     gint     nparams,
     GParam  *param,
     gint    *nreturn_vals,
     GParam **return_vals)
{
  static GParam values[2];
  GRunModeType  run_mode;
  GStatusType   status = STATUS_SUCCESS;
  gint32        image_ID;

  run_mode = param[0].data.d_int32;

  INIT_I18N();

  *nreturn_vals = 1;
  *return_vals  = values;
  values[0].type          = PARAM_STATUS;
  values[0].data.d_status = STATUS_EXECUTION_ERROR;

  if (strcmp (name, "file_gz_load") == 0)
    {
      image_ID = load_image (param[1].data.d_string,
			     param[0].data.d_int32,
			     &status);

      if (image_ID != -1 &&
	  status == STATUS_SUCCESS)
	{
	  *nreturn_vals = 2;
	  values[1].type         = PARAM_IMAGE;
	  values[1].data.d_image = image_ID;
	}
    }
  else if (strcmp (name, "file_gz_save") == 0)
    {
      switch (run_mode)
	{
	case RUN_INTERACTIVE:
	  break;
	case RUN_NONINTERACTIVE:
	  /*  Make sure all the arguments are there!  */
	  if (nparams != 4)
	    status = STATUS_CALLING_ERROR;
	  break;
	case RUN_WITH_LAST_VALS:
	  break;

	default:
	  break;
	}

      if (status == STATUS_SUCCESS)
	{
	  status = save_image (param[3].data.d_string,
			       param[1].data.d_int32,
			       param[2].data.d_int32,
			       param[0].data.d_int32);
	 }
    }
  else
    {
      status = STATUS_CALLING_ERROR;
    }

  values[0].data.d_status = status;
}

#ifdef __EMX__
static gint
spawn_gzip (gchar *filename,
	    gchar *tmpname,
	    gchar *parms,
	    gint  *pid)
{
  FILE *f;
  gint tfd;
  
  if (!(f = fopen (filename,"w")))
    {
      g_message ("gz: fopen failed: %s\n", g_strerror (errno));
      return -1;
    }

  /* save fileno(stdout) */
  tfd = dup (fileno (stdout));
  /* make stdout for this process be the output file */
  if (dup2 (fileno (f), fileno (stdout)) == -1)
    {
      g_message ("gz: dup2 failed: %s\n", g_strerror (errno));
      close (tfd);
      return -1;
    }
  fcntl (tfd, F_SETFD, FD_CLOEXEC);
  *pid = spawnlp (P_NOWAIT, "gzip", "gzip", parms, tmpname, NULL);
  fclose (f);
  /* restore fileno(stdout) */
  dup2 (tfd, fileno (stdout));
  close (tfd);
  if (*pid == -1)
    {
      g_message ("gz: spawn failed: %s\n", g_strerror (errno));
      return -1;
    }
  return 0;
}
#endif

static GStatusType
save_image (gchar  *filename,
	    gint32  image_ID,
	    gint32  drawable_ID,
	    gint32  run_mode)
{
  GParam* params;
  gint retvals;
  gchar *ext;
  gchar *tmpname;
#ifndef G_OS_WIN32
  FILE *f;
  gint pid;
  gint status;
#else
  SECURITY_ATTRIBUTES secattr;
  HANDLE f;
  STARTUPINFO startupinfo;
  PROCESS_INFORMATION processinfo;
  gchar *cmdline;
#endif

  if (NULL == (ext = find_extension (filename)))
    {
      g_message (_("gz: no sensible extension, saving as gzip'd xcf\n"));
      ext = ".xcf";
    }

  /* get a temp name with the right extension and save into it. */

  params = gimp_run_procedure ("gimp_temp_name",
			       &retvals,
			       PARAM_STRING, ext + 1,
			       PARAM_END);

  tmpname = g_strdup (params[1].data.d_string);
  gimp_destroy_params (params, retvals);

  params = gimp_run_procedure ("gimp_file_save",
			       &retvals,
 			       PARAM_INT32, run_mode,
			       PARAM_IMAGE, image_ID,
			       PARAM_DRAWABLE, drawable_ID,
			       PARAM_STRING, tmpname,
			       PARAM_STRING, tmpname,
			       PARAM_END);

  if (!valid_file (tmpname) ||
      params[0].data.d_status != STATUS_SUCCESS)
    {
      unlink (tmpname);
      g_free (tmpname);
      return params[0].data.d_status;
    }

/*   if (! file_save(image_ID, tmpname, tmpname)) { */
/*     unlink (tmpname); */
/*     return -1; */
/*   } */

#ifndef G_OS_WIN32
#ifndef __EMX__
  /* fork off a gzip process */
  if ((pid = fork ()) < 0)
    {
      g_message ("gz: fork failed: %s\n", g_strerror (errno));
      g_free (tmpname);
      return STATUS_EXECUTION_ERROR;
    }
  else if (pid == 0)
    {

      if (!(f = fopen (filename, "w")))
	{
	  g_message ("gz: fopen failed: %s\n", g_strerror (errno));
	  g_free (tmpname);
	  _exit (127);
	}

      /* make stdout for this process be the output file */
      if (-1 == dup2 (fileno (f), fileno (stdout)))
	g_message ("gz: dup2 failed: %s\n", g_strerror (errno));

      /* and gzip into it */
      execlp ("gzip", "gzip", "-cf", tmpname, NULL);
      g_message ("gz: exec failed: gzip: %s\n", g_strerror (errno));
      g_free (tmpname);
      _exit(127);
    }
  else
#else /* __EMX__ */
  if (spawn_gzip (filename, tmpname, "-cf", &pid) == -1)  
    {
      g_free (tmpname);
      return STATUS_EXECUTION_ERROR;
    }
#endif
    {
      waitpid (pid, &status, 0);

      if (!WIFEXITED (status) ||
	  WEXITSTATUS (status) != 0)
	{
	  g_message ("gz: gzip exited abnormally on file %s\n", tmpname);
	  g_free (tmpname);
	  return 0;
	}
    }
#else  /* G_OS_WIN32 */
  secattr.nLength = sizeof (SECURITY_ATTRIBUTES);
  secattr.lpSecurityDescriptor = NULL;
  secattr.bInheritHandle = TRUE;

  if ((f = CreateFile (filename, GENERIC_WRITE, FILE_SHARE_READ,
		       &secattr, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL))
      == INVALID_HANDLE_VALUE)
    {
      g_message ("gz: CreateFile failed\n");
      g_free (tmpname);
      _exit (127);
    }

  startupinfo.cb = sizeof (STARTUPINFO);
  startupinfo.lpReserved = NULL;
  startupinfo.lpDesktop = NULL;
  startupinfo.lpTitle = NULL;
  startupinfo.dwFlags =
    STARTF_FORCEOFFFEEDBACK | STARTF_USESHOWWINDOW | STARTF_USESTDHANDLES;
  startupinfo.wShowWindow = SW_SHOWMINNOACTIVE;
  startupinfo.cbReserved2 = 0;
  startupinfo.lpReserved2 = NULL;
  startupinfo.hStdInput = GetStdHandle (STD_INPUT_HANDLE);
  startupinfo.hStdOutput = f;
  startupinfo.hStdError = GetStdHandle (STD_ERROR_HANDLE);

  cmdline = g_strdup_printf ("gzip -cf %s", tmpname);

  if (!CreateProcess (NULL, cmdline, NULL, NULL,
		      TRUE, NORMAL_PRIORITY_CLASS, NULL, NULL,
		      &startupinfo, &processinfo))
    {
      g_message ("gz: CreateProcess failed\n");
      g_free (tmpname);
      _exit (127);
    }
  CloseHandle (f);
  CloseHandle (processinfo.hThread);
  WaitForSingleObject (processinfo.hProcess, INFINITE);
#endif /* G_OS_WIN32 */

  unlink (tmpname);
  g_free (tmpname);

  return STATUS_SUCCESS;
}

static gint32
load_image (gchar       *filename,
	    gint32       run_mode,
	    GStatusType *status /* return value */)
{
  GParam* params;
  gint retvals;
  gchar *ext;
  gchar *tmpname;
#ifndef G_OS_WIN32
  gint pid;
  gint process_status;
#else
  SECURITY_ATTRIBUTES secattr;
  HANDLE f;
  STARTUPINFO startupinfo;
  PROCESS_INFORMATION processinfo;
  gchar *cmdline;
#endif

  if (NULL == (ext = find_extension (filename)))
    {
      g_message (_("gz: no sensible extension, attempting to load with file magic\n"));
    }

  /* find a temp name */
  params = gimp_run_procedure ("gimp_temp_name",
			       &retvals,
			       PARAM_STRING, ext + 1,
			       PARAM_END);

  tmpname = g_strdup (params[1].data.d_string);
  gimp_destroy_params (params, retvals);

#ifndef G_OS_WIN32
#ifndef __EMX__
  /* fork off a g(un)zip and wait for it */
  if ((pid = fork ()) < 0)
    {
      g_message ("gz: fork failed: %s\n", g_strerror (errno));
      g_free (tmpname);
      *status = STATUS_EXECUTION_ERROR;
      return -1;
    }
  else if (pid == 0)  /* child process */
    {
      FILE *f;
       if (!(f = fopen (tmpname, "w")))
	 {
	   g_message ("gz: fopen failed: %s\n", g_strerror (errno));
	   g_free (tmpname);
	   _exit(127);
	 }

      /* make stdout for this child process be the temp file */
      if (-1 == dup2 (fileno (f), fileno (stdout)))
	{
	  g_free (tmpname);
	  g_message ("gz: dup2 failed: %s\n", g_strerror (errno));
	}

      /* and unzip into it */
      execlp ("gzip", "gzip", "-cfd", filename, NULL);
      g_message ("gz: exec failed: gunzip: %s\n", g_strerror (errno));
      g_free (tmpname);
      _exit(127);
    }
  else  /* parent process */
#else /* __EMX__ */
   if (spawn_gzip (tmpname, filename, "-cfd", &pid) == -1)
     {
       g_free (tmpname);
       *status = STATUS_EXECUTION_ERROR;
       return -1;
     }
#endif
    {
      waitpid (pid, &process_status, 0);

      if (!WIFEXITED (process_status) ||
	  WEXITSTATUS (process_status) != 0)
	{
	  g_message ("gz: gzip exited abnormally on file %s\n", filename);
	  g_free (tmpname);
	  *status = STATUS_EXECUTION_ERROR;
	  return -1;
	}
    }
#else
  secattr.nLength = sizeof (SECURITY_ATTRIBUTES);
  secattr.lpSecurityDescriptor = NULL;
  secattr.bInheritHandle = TRUE;

  if ((f = CreateFile (tmpname, GENERIC_WRITE, FILE_SHARE_READ,
		       &secattr, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL))
      == INVALID_HANDLE_VALUE)
    {
      g_message ("gz: CreateFile failed\n");
      g_free (tmpname);
      _exit (127);
    }

  startupinfo.cb = sizeof (STARTUPINFO);
  startupinfo.lpReserved = NULL;
  startupinfo.lpDesktop = NULL;
  startupinfo.lpTitle = NULL;
  startupinfo.dwFlags =
    STARTF_FORCEOFFFEEDBACK | STARTF_USESHOWWINDOW | STARTF_USESTDHANDLES;
  startupinfo.wShowWindow = SW_SHOWMINNOACTIVE;
  startupinfo.cbReserved2 = 0;
  startupinfo.lpReserved2 = NULL;
  startupinfo.hStdInput = GetStdHandle (STD_INPUT_HANDLE);
  startupinfo.hStdOutput = f;
  startupinfo.hStdError = GetStdHandle (STD_ERROR_HANDLE);

  cmdline = g_strdup_printf ("gzip -cfd %s", filename);

  if (!CreateProcess (NULL, cmdline, NULL, NULL,
		      TRUE, NORMAL_PRIORITY_CLASS, NULL, NULL,
		      &startupinfo, &processinfo))
    {
      g_message ("gz: CreateProcess failed: %d\n", GetLastError ());
      g_free (tmpname);
      _exit (127);
    }
  CloseHandle (f);
  CloseHandle (processinfo.hThread);
  WaitForSingleObject (processinfo.hProcess, INFINITE);
#endif /* G_OS_WIN32 */

  /* now that we un-gziped it, load the temp file */

  params = gimp_run_procedure ("gimp_file_load",
			       &retvals,
			       PARAM_INT32, run_mode,
			       PARAM_STRING, tmpname,
			       PARAM_STRING, tmpname,
			       PARAM_END);
  unlink (tmpname);
  g_free (tmpname);

  *status = params[0].data.d_status;

  if (params[0].data.d_status != STATUS_SUCCESS)
    {
      return -1;
    }
  else
    {
      gimp_image_set_filename (params[1].data.d_int32, filename);
      return params[1].data.d_int32;
    }
}

static gboolean
valid_file (gchar *filename)
{
  gint stat_res;
  struct stat buf;

  stat_res = stat(filename, &buf);

  if ((0 == stat_res) && (buf.st_size > 0))
    return TRUE;
  else
    return FALSE;
}

static gchar *
find_extension (gchar *filename)
{
  gchar *filename_copy;
  gchar *ext;

  /* we never free this copy - aren't we evil! */
  filename_copy = g_malloc (strlen (filename) + 1);
  strcpy (filename_copy, filename);

  /* find the extension, boy! */
  ext = strrchr (filename_copy, '.');

  while (1)
    {
      if (!ext || ext[1] == 0 || strchr (ext, '/'))
	{
	  return NULL;
	}
      if (0 == strcmp (ext, ".xcfgz"))
	{
	  return ".xcf";  /* we've found it */
	}
      if (0 != strcmp (ext,".gz"))
	{
	  return ext;
	}
      else
	{
	  /* we found ".gz" so strip it, loop back, and look again */
	  *ext = 0;
	  ext = strrchr (filename_copy, '.');
	}
    }
}