/*
 * Nautilus
 *
 * Copyright (C) 2011 Red Hat, Inc.
 *
 * Nautilus 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.
 *
 * Nautilus 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; see the file COPYING.  If not,
 * see <http://www.gnu.org/licenses/>.
 *
 * Authors: Cosimo Cecchi <cosimoc@redhat.com>
 */

#include <config.h>

#include "nautilus-keyfile-metadata.h"

#include "nautilus-directory-notify.h"
#include "nautilus-file-private.h"
#include "nautilus-file-utilities.h"

#include <glib/gstdio.h>

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>

typedef struct {
	GKeyFile *keyfile;
	guint save_in_idle_id;
} KeyfileMetadataData;

static GHashTable *data_hash = NULL;

static KeyfileMetadataData *
keyfile_metadata_data_new (const char *keyfile_filename)
{
	KeyfileMetadataData *data;
	GKeyFile *retval;
	GError *error = NULL;

	retval = g_key_file_new ();

	g_key_file_load_from_file (retval,
	                           keyfile_filename,
	                           G_KEY_FILE_NONE,
	                           &error);

	if (error != NULL) {
		if (!g_error_matches (error,
		                      G_FILE_ERROR,
		                      G_FILE_ERROR_NOENT)) {
			g_print ("Unable to open the desktop metadata keyfile: %s\n",
			         error->message);
		}

		g_error_free (error);
	}

	data = g_slice_new0 (KeyfileMetadataData);
	data->keyfile = retval;

	return data;
}

static void
keyfile_metadata_data_free (KeyfileMetadataData *data)
{
	g_key_file_unref (data->keyfile);

	if (data->save_in_idle_id != 0) {
		g_source_remove (data->save_in_idle_id);
	}

	g_slice_free (KeyfileMetadataData, data);
}

static GKeyFile *
get_keyfile (const char *keyfile_filename)
{
	KeyfileMetadataData *data;

	if (data_hash == NULL) {
		data_hash = g_hash_table_new_full (g_str_hash,
		                                   g_str_equal,
		                                   g_free,
		                                   (GDestroyNotify) keyfile_metadata_data_free);
	}

	data = g_hash_table_lookup (data_hash, keyfile_filename);

	if (data == NULL) {
		data = keyfile_metadata_data_new (keyfile_filename);

		g_hash_table_insert (data_hash,
		                     g_strdup (keyfile_filename),
		                     data);
	}

	return data->keyfile;
}

static gboolean
save_in_idle_cb (const gchar *keyfile_filename)
{
	KeyfileMetadataData *data;
	gchar *contents;
	gsize length;
	GError *error = NULL;

	data = g_hash_table_lookup (data_hash, keyfile_filename);
	data->save_in_idle_id = 0;

	contents = g_key_file_to_data (data->keyfile, &length, NULL);

	if (contents != NULL) {
		g_file_set_contents (keyfile_filename,
		                     contents, length,
		                     &error);
		g_free (contents);
	}

	if (error != NULL) {
		g_warning ("Couldn't save the desktop metadata keyfile to disk: %s",
		           error->message);
		g_error_free (error);
	}

	return FALSE;
}

static void
save_in_idle (const char *keyfile_filename)
{
	KeyfileMetadataData *data;

	g_return_if_fail (data_hash != NULL);

	data = g_hash_table_lookup (data_hash, keyfile_filename);
	g_return_if_fail (data != NULL);

	if (data->save_in_idle_id != 0) {
		return;
	}

	data->save_in_idle_id = g_idle_add_full (G_PRIORITY_DEFAULT_IDLE,
	                                         (GSourceFunc) save_in_idle_cb,
	                                         g_strdup (keyfile_filename),
	                                         g_free);
}

void
nautilus_keyfile_metadata_set_string (NautilusFile *file,
                                      const char *keyfile_filename,
                                      const gchar *name,
                                      const gchar *key,
                                      const gchar *string)
{
	GKeyFile *keyfile;

	keyfile = get_keyfile (keyfile_filename);

	g_key_file_set_string (keyfile,
	                       name,
	                       key,
	                       string);

	save_in_idle (keyfile_filename);

	if (nautilus_keyfile_metadata_update_from_keyfile (file, keyfile_filename, name)) {
		nautilus_file_changed (file);
	}
}

#define STRV_TERMINATOR "@x-nautilus-desktop-metadata-term@"

void
nautilus_keyfile_metadata_set_stringv (NautilusFile *file,
                                       const char *keyfile_filename,
                                       const char *name,
                                       const char *key,
                                       const char * const *stringv)
{
	GKeyFile *keyfile;
	guint length;
	gchar **actual_stringv = NULL;
	gboolean free_strv = FALSE;

	keyfile = get_keyfile (keyfile_filename);

	/* if we would be setting a single-length strv, append a fake
	 * terminator to the array, to be able to differentiate it later from
	 * the single string case
	 */
	length = g_strv_length ((gchar **) stringv);

	if (length == 1) {
		actual_stringv = g_malloc0 (3 * sizeof (gchar *));
		actual_stringv[0] = (gchar *) stringv[0];
		actual_stringv[1] = STRV_TERMINATOR;
		actual_stringv[2] = NULL;

		length = 2;
		free_strv = TRUE;
	} else {
		actual_stringv = (gchar **) stringv;
	}

	g_key_file_set_string_list (keyfile,
	                            name,
	                            key,
	                            (const gchar **) actual_stringv,
	                            length);

	save_in_idle (keyfile_filename);

	if (nautilus_keyfile_metadata_update_from_keyfile (file, keyfile_filename, name)) {
		nautilus_file_changed (file);
	}

	if (free_strv) {
		g_free (actual_stringv);
	}
}

gboolean
nautilus_keyfile_metadata_update_from_keyfile (NautilusFile *file,
                                               const char *keyfile_filename,
                                               const gchar *name)
{
	gchar **keys, **values;
	const gchar *actual_values[2];
	const gchar *key, *value;
	gchar *gio_key;
	gsize length, values_length;
	GKeyFile *keyfile;
	GFileInfo *info;
	gint idx;
	gboolean res;

	keyfile = get_keyfile (keyfile_filename);

	keys = g_key_file_get_keys (keyfile,
	                            name,
	                            &length,
	                            NULL);

	if (keys == NULL) {
		return FALSE;
	}

	info = g_file_info_new ();

	for (idx = 0; idx < length; idx++) {
		key = keys[idx];
		values = g_key_file_get_string_list (keyfile,
		                                     name,
		                                     key,
		                                     &values_length,
		                                     NULL);

		gio_key = g_strconcat ("metadata::", key, NULL);

		if (values_length < 1) {
			continue;
		} else if (values_length == 1) {
			g_file_info_set_attribute_string (info,
			                                  gio_key,
			                                  values[0]);
		} else if (values_length == 2) {
			/* deal with the fact that single-length strv are stored
			 * with an additional terminator in the keyfile string, to differentiate
			 * them from the regular string case.
			 */
			value = values[1];

			if (g_strcmp0 (value, STRV_TERMINATOR) == 0) {
				/* if the 2nd value is the terminator, remove it */
				actual_values[0] = values[0];
				actual_values[1] = NULL;

				g_file_info_set_attribute_stringv (info,
				                                   gio_key,
				                                   (gchar **) actual_values);
			} else {
				/* otherwise, set it as a regular strv */
				g_file_info_set_attribute_stringv (info,
				                                   gio_key,
				                                   values);
			}
		} else {
			g_file_info_set_attribute_stringv (info,
			                                   gio_key,
			                                   values);
		}

		g_free (gio_key);
		g_strfreev (values);
	}

	res = nautilus_file_update_metadata_from_info (file, info);

	g_strfreev (keys);
	g_object_unref (info);

	return res;
}