/*
 * 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;
}