/* -*- mode: C; c-file-style: "linux" -*- */
/* GdkPixbuf library
 * queryloaders.c:
 *
 * Copyright (C) 2002 The Free Software Foundation
 * 
 * Author: Matthias Clasen <maclas@gmx.de>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 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
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */

#include <config.h>

#include <glib.h>
#include <glib/gprintf.h>
#include <gmodule.h>

#include <errno.h>
#include <string.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif

#include "gdk-pixbuf/gdk-pixbuf.h"
#include "gdk-pixbuf/gdk-pixbuf-private.h"
#include "gdk-pixbuf/gdk-pixbuf-io.h"

#if USE_LA_MODULES
#define SOEXT ".la"
#else
#define SOEXT ("." G_MODULE_SUFFIX)
#endif
#define SOEXT_LEN (strlen (SOEXT))

static void
print_escaped (const char *str)
{
	gchar *tmp = g_strescape (str, "");
	g_printf ("\"%s\" ", tmp);
	g_free (tmp);
}

static int
loader_sanity_check (const char *path, GdkPixbufFormat *info, GdkPixbufModule *vtable)
{
	const GdkPixbufModulePattern *pattern;
	const char *error = "";

	for (pattern = info->signature; pattern->prefix; pattern++) 
	{
		int prefix_len = strlen (pattern->prefix);
		if (prefix_len == 0) 
		{
			error = "empty pattern";

			goto error;
		}
		if (pattern->mask)
		{
			int mask_len = strlen (pattern->mask);
			if (mask_len != prefix_len)
			{
				error = "mask length mismatch";
				
				goto error;
			}
			if (strspn (pattern->mask, " !xzn") < mask_len) 
			{
				error = "bad char in mask";
				
				goto error;
			}
		}
	}

	if (!vtable->load && !vtable->begin_load && !vtable->load_animation)
	{
		error = "no load method implemented";

		goto error;
	}

	if (vtable->begin_load && (!vtable->stop_load || !vtable->load_increment))
	{
		error = "incremental loading support incomplete";

		goto error;
	}

	if ((info->flags & GDK_PIXBUF_FORMAT_WRITABLE) && !vtable->save) 
	{
		error = "loader claims to support saving but doesn't implement save";
		goto error;
	}
	    
	return 1;

 error:
	g_fprintf (stderr, "Loader sanity check failed for %s: %s\n", 
		   path, error);
	
	return 0;
}

static void 
write_loader_info (const char *path, GdkPixbufFormat *info)
{
	const GdkPixbufModulePattern *pattern;
	char **mime; 
	char **ext; 

	g_printf("\"%s\"\n", path);
	g_printf ("\"%s\" %d \"%s\" \"%s\"\n", 
		  info->name, info->flags, 
		  info->domain ? info->domain : GETTEXT_PACKAGE, info->description);
	for (mime = info->mime_types; *mime; mime++) {
		g_printf ("\"%s\" ", *mime);
	}
	g_printf ("\"\"\n");
	for (ext = info->extensions; *ext; ext++) {
		g_printf ("\"%s\" ", *ext);
	}
	g_printf ("\"\"\n");
	for (pattern = info->signature; pattern->prefix; pattern++) {
		print_escaped (pattern->prefix);
		print_escaped (pattern->mask ? (const char *)pattern->mask : "");
		g_printf ("%d\n", pattern->relevance);
	}
	g_printf ("\n");
}

static void
query_module (const char *dir, const char *file)
{
	char *path;
	GModule *module;
	void                    (*fill_info)     (GdkPixbufFormat *info);
	void                    (*fill_vtable)   (GdkPixbufModule *module);

	if (g_path_is_absolute (file)) 
		path = g_strdup (file);
	else
		path = g_build_filename (dir, file, NULL);

	module = g_module_open (path, 0);
	if (module &&
	    g_module_symbol (module, "fill_info", (gpointer *) &fill_info) &&
	    g_module_symbol (module, "fill_vtable", (gpointer *) &fill_vtable)) {
		GdkPixbufFormat *info;
		GdkPixbufModule *vtable;
		
#ifdef G_OS_WIN32
		/* Replace backslashes in path with forward slashes, so that
		 * it reads in without problems.
		 */
		{
			char *p = path;
			while (*p) {
				if (*p == '\\')
					*p = '/';
				p++;
			}
		}
#endif	
		info = g_new0 (GdkPixbufFormat, 1);
		vtable = g_new0 (GdkPixbufModule, 1);
		
		(*fill_info) (info);
		(*fill_vtable) (vtable);
		
		if (loader_sanity_check (path, info, vtable)) 
			write_loader_info (path, info);
		
		g_free (info);
		g_free (vtable);
	}
	else {
		if (module == NULL)
			g_fprintf (stderr, "g_module_open() failed for %s: %s\n", path,
				   g_module_error());
	        else
			g_fprintf (stderr, "Cannot load loader %s\n", path);
	}
	if (module)
		g_module_close (module);
	g_free (path);
}

int main (int argc, char **argv)
{
	gint i;

	g_printf ("# GdkPixbuf Image Loader Modules file\n"
		"# Automatically generated file, do not edit\n"
		"#\n");
  
	if (argc == 1) {
#ifdef USE_GMODULE
		const char *path;
		GDir *dir;
    
		path = g_getenv ("GDK_PIXBUF_MODULEDIR");
		if (path == NULL || *path == '\0')
			path = PIXBUF_LIBDIR;

		g_printf ("# LoaderDir = %s\n#\n", path);

		dir = g_dir_open (path, 0, NULL);
		if (dir) {
			const char *dent;

			while ((dent = g_dir_read_name (dir))) {
				gint len = strlen (dent);
				if (len > SOEXT_LEN && 
				    strcmp (dent + len - SOEXT_LEN, SOEXT) == 0) {
					query_module (path, dent);
				}
			}
			g_dir_close (dir);
		}
#else
		g_printf ("# dynamic loading of modules not supported\n");
#endif
	}
	else {
		char *cwd = g_get_current_dir ();

		for (i = 1; i < argc; i++)
			query_module (cwd, argv[i]);

		g_free (cwd);
	}

	return 0;
}