/*
   paths to configuration files

   Copyright (C) 2010 The Free Software Foundation, Inc.

   Written by:
   Slava Zanko <slavazanko@gmail.com>, 2010.

   This file is part of the Midnight Commander.

   The Midnight Commander 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.

   The Midnight Commander 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., 51 Franklin Street, Fifth Floor, Boston,
   MA 02110-1301, USA.
 */

#include <config.h>

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

#include "lib/global.h"
#include "lib/fileloc.h"
#include "lib/vfs/vfs.h"
#include "lib/util.h.h"         /* unix_error_string() */

#include "lib/mcconfig.h"

/*** global variables ****************************************************************************/

/*** file scope macro definitions ****************************************************************/

/*** file scope type declarations ****************************************************************/

/*** file scope variables ************************************************************************/

static gboolean xdg_vars_initialized = FALSE;
static char *xdg_config = NULL;
static char *xdg_cache = NULL;
static char *xdg_data = NULL;

static const char *homedir = NULL;

static gboolean config_dir_present = FALSE;

static const struct
{
    const char *old_filename;

    char **new_basedir;
    const char *new_filename;
} mc_config_migrate_rules[] =
{
    /* *INDENT-OFF* */
    /* config */
    { "ini",                                   &xdg_config, MC_CONFIG_FILE},
    { "filehighlight.ini",                     &xdg_config, MC_FHL_INI_FILE},
    { "hotlist",                               &xdg_config, MC_HOTLIST_FILE},
    { "mc.keymap",                             &xdg_config, GLOBAL_KEYMAP_FILE},

    /* data */
    { "skins",                                 &xdg_data, MC_SKINS_SUBDIR},
    { "fish",                                  &xdg_data, FISH_PREFIX},
    { "bindings",                              &xdg_data, MC_FILEBIND_FILE},
    { "menu",                                  &xdg_data, MC_USERMENU_FILE},
    { "bashrc",                                &xdg_data, "bashrc"},
    { "inputrc",                               &xdg_data, "inputrc"},
    { "extfs.d",                               &xdg_data, MC_EXTFS_DIR},
    { "cedit" PATH_SEP_STR "Syntax",           &xdg_data, EDIT_SYNTAX_FILE},
    { "cedit" PATH_SEP_STR "menu",             &xdg_data, EDIT_HOME_MENU},
    { "cedit" PATH_SEP_STR "edit.indent.rc",   &xdg_data, EDIT_DIR PATH_SEP_STR "edit.indent.rc"},
    { "cedit" PATH_SEP_STR "edit.spell.rc",    &xdg_data, EDIT_DIR PATH_SEP_STR "edit.spell.rc"},

    /* cache */
    { "history",                               &xdg_cache, MC_HISTORY_FILE},
    { "panels.ini",                            &xdg_cache, MC_PANELS_FILE},
    { "log",                                   &xdg_cache, "mc.log"},
    { "filepos",                               &xdg_cache, MC_FILEPOS_FILE},
    { "Tree",                                  &xdg_cache, MC_TREESTORE_FILE},
    { "cedit" PATH_SEP_STR "cooledit.clip",    &xdg_cache, EDIT_CLIP_FILE},
    { "cedit" PATH_SEP_STR "cooledit.temp",    &xdg_cache, EDIT_TEMP_FILE},
    { "cedit" PATH_SEP_STR "cooledit.block",   &xdg_cache, EDIT_BLOCK_FILE},

    {NULL, NULL, NULL}
    /* *INDENT-ON* */
};

/*** file scope functions *********************************************************************** */
/* --------------------------------------------------------------------------------------------- */

static void
mc_config_mkdir (const char *directory_name, GError ** error)
{
    if ((!g_file_test (directory_name, G_FILE_TEST_EXISTS | G_FILE_TEST_IS_DIR)) &&
        (g_mkdir_with_parents (directory_name, 0700) != 0))
    {
        g_propagate_error (error,
                           g_error_new (MC_ERROR, 0, _("Cannot create %s directory"),
                                        directory_name));
    }
}

/* --------------------------------------------------------------------------------------------- */

static char *
mc_config_init_one_config_path (const char *path_base, const char *subdir, GError ** error)
{
    char *full_path;

    full_path = g_build_filename (path_base, subdir, NULL);

    if (g_file_test (full_path, G_FILE_TEST_EXISTS | G_FILE_TEST_IS_DIR))
        config_dir_present = TRUE;

    mc_config_mkdir (full_path, error);
    if (error != NULL && *error != NULL)
    {
        g_free (full_path);
        full_path = NULL;
    }
    return full_path;
}

/* --------------------------------------------------------------------------------------------- */

static char *
mc_config_get_deprecated_path (void)
{
    return g_build_filename (mc_config_get_home_dir (), "." MC_USERCONF_DIR, NULL);
}

/* --------------------------------------------------------------------------------------------- */

static void
mc_config_copy (const char *old_name, const char *new_name, GError ** error)
{
    if (g_file_test (old_name, G_FILE_TEST_IS_REGULAR))
    {
        char *contents = NULL;
        size_t length;

        if (g_file_get_contents (old_name, &contents, &length, error))
            g_file_set_contents (new_name, contents, length, error);

        g_free (contents);
        return;
    }

    if (g_file_test (old_name, G_FILE_TEST_IS_DIR))
    {

        GDir *dir;
        const char *dir_name;

        dir = g_dir_open (old_name, 0, error);
        if (dir == NULL)
            return;

        if (g_mkdir_with_parents (new_name, 0700) == -1)
        {
            g_dir_close (dir);
            g_propagate_error (error,
                               g_error_new (MC_ERROR, 0,
                                            _
                                            ("An error occured while migrating user settings: %s"),
                                            unix_error_string (errno)));
            return;
        }

        while ((dir_name = g_dir_read_name (dir)) != NULL)
        {
            char *old_name2, *new_name2;

            old_name2 = g_build_filename (old_name, dir_name, NULL);
            new_name2 = g_build_filename (new_name, dir_name, NULL);
            mc_config_copy (old_name2, new_name2, error);
            g_free (new_name2);
            g_free (old_name2);
        }
    }
}

/* --------------------------------------------------------------------------------------------- */
/*** public functions ****************************************************************************/
/* --------------------------------------------------------------------------------------------- */

void
mc_config_init_config_paths (GError ** error)
{
    const char *mc_datadir;

    char *u_config_dir = (char *) g_get_user_config_dir ();
    char *u_data_dir = (char *) g_get_user_data_dir ();
    char *u_cache_dir = (char *) g_get_user_cache_dir ();

    if (xdg_vars_initialized)
        return;

    u_config_dir = (u_config_dir == NULL)
        ? g_build_filename (mc_config_get_home_dir (), ".config", NULL) : g_strdup (u_config_dir);

    u_cache_dir = (u_cache_dir == NULL)
        ? g_build_filename (mc_config_get_home_dir (), ".cache", NULL) : g_strdup (u_cache_dir);

    u_data_dir = (u_data_dir == NULL)
        ? g_build_filename (mc_config_get_home_dir (), ".local", "share", NULL)
        : g_strdup (u_data_dir);

    xdg_config = mc_config_init_one_config_path (u_config_dir, MC_USERCONF_DIR, error);
    xdg_cache = mc_config_init_one_config_path (u_cache_dir, MC_USERCONF_DIR, error);
    xdg_data = mc_config_init_one_config_path (u_data_dir, MC_USERCONF_DIR, error);

    g_free (u_data_dir);
    g_free (u_cache_dir);
    g_free (u_config_dir);

    /* This is the directory, where MC was installed, on Unix this is DATADIR */
    /* and can be overriden by the MC_DATADIR environment variable */
    mc_datadir = g_getenv ("MC_DATADIR");
    if (mc_datadir != NULL)
        mc_global.sysconfig_dir = g_strdup (mc_datadir);
    else
        mc_global.sysconfig_dir = g_strdup (SYSCONFDIR);

    mc_global.share_data_dir = g_strdup (DATADIR);

    xdg_vars_initialized = TRUE;
}

/* --------------------------------------------------------------------------------------------- */

void
mc_config_deinit_config_paths (void)
{
    if (!xdg_vars_initialized)
        return;

    g_free (xdg_config);
    g_free (xdg_cache);
    g_free (xdg_data);

    g_free (mc_global.share_data_dir);
    g_free (mc_global.sysconfig_dir);

    xdg_vars_initialized = FALSE;
}

/* --------------------------------------------------------------------------------------------- */

const char *
mc_config_get_data_path (void)
{
    if (!xdg_vars_initialized)
        mc_config_init_config_paths (NULL);

    return (const char *) xdg_data;
}

/* --------------------------------------------------------------------------------------------- */

const char *
mc_config_get_cache_path (void)
{
    if (!xdg_vars_initialized)
        mc_config_init_config_paths (NULL);

    return (const char *) xdg_cache;
}

/* --------------------------------------------------------------------------------------------- */

const char *
mc_config_get_home_dir (void)
{
    if (homedir == NULL)
    {
        homedir = g_getenv ("HOME");
        if (homedir == NULL)
            homedir = g_get_home_dir ();
    }
    return homedir;
}

/* --------------------------------------------------------------------------------------------- */

const char *
mc_config_get_path (void)
{
    if (!xdg_vars_initialized)
        mc_config_init_config_paths (NULL);

    return (const char *) xdg_config;
}

/* --------------------------------------------------------------------------------------------- */

void
mc_config_migrate_from_old_place (GError ** error)
{
    char *old_dir;
    size_t rule_index;

    old_dir = mc_config_get_deprecated_path ();

    g_free (mc_config_init_one_config_path (xdg_config, EDIT_DIR, error));
    g_free (mc_config_init_one_config_path (xdg_cache, EDIT_DIR, error));
    g_free (mc_config_init_one_config_path (xdg_data, EDIT_DIR, error));

    for (rule_index = 0; mc_config_migrate_rules[rule_index].old_filename != NULL; rule_index++)
    {
        char *old_name;

        old_name =
            g_build_filename (old_dir, mc_config_migrate_rules[rule_index].old_filename, NULL);

        if (g_file_test (old_name, G_FILE_TEST_EXISTS))
        {
            char *new_name;

            new_name = g_build_filename (*mc_config_migrate_rules[rule_index].new_basedir,
                                         mc_config_migrate_rules[rule_index].new_filename, NULL);

            mc_config_copy (old_name, new_name, error);

            g_free (new_name);
        }
        g_free (old_name);
    }

    g_propagate_error (error,
                       g_error_new (MC_ERROR, 0,
                                    _
                                    ("Your old settings were migrated from %s\n"
                                     "to Freedesktop recommended dirs.\n"
                                     "To get more info, please visit\n"
                                     "http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html"),
                                    old_dir));

    g_free (old_dir);
}

/* --------------------------------------------------------------------------------------------- */

gboolean
mc_config_deprecated_dir_present (void)
{
    char *old_dir;
    gboolean is_present;

    old_dir = mc_config_get_deprecated_path ();
    is_present = g_file_test (old_dir, G_FILE_TEST_EXISTS | G_FILE_TEST_IS_DIR);
    g_free (old_dir);

    return is_present && !config_dir_present;
}

/* --------------------------------------------------------------------------------------------- */