/*
 Copyright (C) 2008-2009 Christian Dywan <christian@twotoasts.de>

 This library is free software; you can redistribute it and/or
 modify it under the terms of the GNU Lesser General Public
 License as published by the Free Software Foundation; either
 version 2.1 of the License, or (at your option) any later version.

 See the file COPYING for the full license text.
*/

#include "midori-extension.h"

#if HAVE_CONFIG_H
    #include <config.h>
#endif

#include "midori-app.h"

#include <katze/katze.h>
#include "sokoke.h"
#include <glib/gi18n.h>

G_DEFINE_TYPE (MidoriExtension, midori_extension, G_TYPE_OBJECT);

struct _MidoriExtensionPrivate
{
    gchar* name;
    gchar* description;
    gchar* version;
    gchar* authors;

    gboolean active;
    gchar* config_dir;
    GList* lsettings;
    GHashTable* settings;
    GKeyFile* key_file;
};

typedef struct
{
    gchar* name;
    GType type;
    gboolean default_value;
    gboolean value;
} MESettingBoolean;

typedef struct
{
    gchar* name;
    GType type;
    gint default_value;
    gint value;
} MESettingInteger;

typedef struct
{
    gchar* name;
    GType type;
    gchar* default_value;
    gchar* value;
} MESettingString;

void me_setting_free (gpointer setting)
{
    MESettingString* string_setting = (MESettingString*)setting;

    g_free (string_setting->name);
    if (string_setting->type == G_TYPE_STRING)
    {
        g_free (string_setting->default_value);
        g_free (string_setting->value);
    }
}

#define midori_extension_can_install_setting(extension, name) \
    if (extension->priv->active) \
    { \
        g_critical ("%s: Settings have to be installed before " \
                    "the extension is activated.", G_STRFUNC); \
        return; \
    } \
    if (g_hash_table_lookup (extension->priv->settings, name)) \
    { \
        g_critical ("%s: A setting with the name '%s' is already installed.", \
                    G_STRFUNC, name); \
        return; \
    }

#define me_setting_install(stype, _name, gtype, _default_value, _value) \
    setting = g_new (stype, 1); \
    setting->name = _name; \
    setting->type = gtype; \
    setting->default_value = _default_value; \
    setting->value = _value; \
    g_hash_table_insert (extension->priv->settings, setting->name, setting); \
    extension->priv->lsettings = g_list_prepend \
        (extension->priv->lsettings, setting);

#define me_setting_type(setting, gtype, rreturn) \
if (!setting) { \
g_critical ("%s: There is no setting with the name '%s' installed.", G_STRFUNC, name); \
rreturn; } \
if (setting->type != gtype) { \
g_critical ("%s: The setting '%s' is not a string.", G_STRFUNC, name); \
rreturn; }

enum
{
    PROP_0,

    PROP_NAME,
    PROP_DESCRIPTION,
    PROP_VERSION,
    PROP_AUTHORS
};

enum {
    ACTIVATE,
    DEACTIVATE,

    LAST_SIGNAL
};

static guint signals[LAST_SIGNAL];

static void
midori_extension_finalize (GObject* object);

static void
midori_extension_set_property (GObject*      object,
                               guint         prop_id,
                               const GValue* value,
                               GParamSpec*   pspec);

static void
midori_extension_get_property (GObject*    object,
                               guint       prop_id,
                               GValue*     value,
                               GParamSpec* pspec);

static void
midori_extension_class_init (MidoriExtensionClass* class)
{
    GObjectClass* gobject_class;
    GParamFlags flags;

    signals[ACTIVATE] = g_signal_new (
        "activate",
        G_TYPE_FROM_CLASS (class),
        (GSignalFlags)(G_SIGNAL_RUN_LAST | G_SIGNAL_ACTION),
        0,
        0,
        NULL,
        g_cclosure_marshal_VOID__OBJECT,
        G_TYPE_NONE, 1,
        MIDORI_TYPE_APP);

    signals[DEACTIVATE] = g_signal_new (
        "deactivate",
        G_TYPE_FROM_CLASS (class),
        (GSignalFlags)(G_SIGNAL_RUN_LAST | G_SIGNAL_ACTION),
        0,
        0,
        NULL,
        g_cclosure_marshal_VOID__VOID,
        G_TYPE_NONE, 0,
        G_TYPE_NONE);

    gobject_class = G_OBJECT_CLASS (class);
    gobject_class->finalize = midori_extension_finalize;
    gobject_class->set_property = midori_extension_set_property;
    gobject_class->get_property = midori_extension_get_property;

    flags = G_PARAM_READWRITE | G_PARAM_CONSTRUCT | G_PARAM_STATIC_STRINGS;

    g_object_class_install_property (gobject_class,
                                     PROP_NAME,
                                     g_param_spec_string (
                                     "name",
                                     "Name",
                                     "The name of the extension",
                                     NULL,
                                     flags));

    g_object_class_install_property (gobject_class,
                                     PROP_DESCRIPTION,
                                     g_param_spec_string (
                                     "description",
                                     "Description",
                                     "The description of the extension",
                                     NULL,
                                     flags));

    g_object_class_install_property (gobject_class,
                                     PROP_VERSION,
                                     g_param_spec_string (
                                     "version",
                                     "Version",
                                     "The version of the extension",
                                     NULL,
                                     flags));

    g_object_class_install_property (gobject_class,
                                     PROP_AUTHORS,
                                     g_param_spec_string (
                                     "authors",
                                     "Authors",
                                     "The authors of the extension",
                                     NULL,
                                     flags));

    g_type_class_add_private (class, sizeof (MidoriExtensionPrivate));
}

static void
midori_extension_activate_cb (MidoriExtension* extension,
                              MidoriApp*       app)
{
    GList* lsettings = g_list_first (extension->priv->lsettings);

    /* If a configuration directory was requested before activation we
       assume we should load and save settings. This is a detail that
       extension writers shouldn't worry about. */
    extension->priv->key_file = lsettings && extension->priv->config_dir
        ? g_key_file_new () :  NULL;
    if (extension->priv->key_file)
    {
        gchar* config_file;
        GError* error = NULL;

        config_file = g_build_filename (extension->priv->config_dir, "config", NULL);
        if (!g_key_file_load_from_file (extension->priv->key_file, config_file,
                                        G_KEY_FILE_KEEP_COMMENTS, &error))
        {
            if (error->code != G_FILE_ERROR_NOENT)
                printf (_("The configuration of the extension '%s' couldn't be loaded: %s\n"),
                        extension->priv->name, error->message);
            g_error_free (error);
        }
    }

    while (lsettings)
    {
        MESettingString* setting = (MESettingString*)lsettings->data;

        if (setting->type == G_TYPE_BOOLEAN)
        {
            MESettingBoolean* setting_ = (MESettingBoolean*)setting;
            if (extension->priv->key_file)
                setting_->value = sokoke_key_file_get_boolean_default (
                    extension->priv->key_file,
                    "settings", setting->name, setting_->default_value, NULL);
            else
                setting_->value = setting_->default_value;
        }
        else if (setting->type == G_TYPE_INT)
        {
            MESettingInteger* setting_ = (MESettingInteger*)setting;
            if (extension->priv->key_file)
                setting_->value = sokoke_key_file_get_integer_default (
                    extension->priv->key_file,
                    "settings", setting->name, setting_->default_value, NULL);
            else
                setting_->value = setting_->default_value;
        }
        else if (setting->type == G_TYPE_STRING)
        {
            if (extension->priv->key_file)
                setting->value = sokoke_key_file_get_string_default (
                    extension->priv->key_file,
                    "settings", setting->name, setting->default_value, NULL);
            else
                setting->value = g_strdup (setting->default_value);
        }
        else
            g_assert_not_reached ();

        lsettings = g_list_next (lsettings);
    }

    extension->priv->active = TRUE;
    /* FIXME: Disconnect all signal handlers */
}

static void
midori_extension_init (MidoriExtension* extension)
{
    extension->priv = G_TYPE_INSTANCE_GET_PRIVATE (extension,
        MIDORI_TYPE_EXTENSION, MidoriExtensionPrivate);

    extension->priv->active = FALSE;
    extension->priv->config_dir = NULL;
    extension->priv->lsettings = NULL;
    extension->priv->settings = g_hash_table_new_full (g_str_hash, g_str_equal,
        g_free, me_setting_free);
    extension->priv->key_file = NULL;

    g_signal_connect (extension, "activate",
        G_CALLBACK (midori_extension_activate_cb), NULL);
}

static void
midori_extension_finalize (GObject* object)
{
    MidoriExtension* extension = MIDORI_EXTENSION (object);

    katze_assign (extension->priv->name, NULL);
    katze_assign (extension->priv->description, NULL);
    katze_assign (extension->priv->version, NULL);
    katze_assign (extension->priv->authors, NULL);

    katze_assign (extension->priv->config_dir, NULL);
    g_list_free (extension->priv->lsettings);
    g_hash_table_destroy (extension->priv->settings);
    if (extension->priv->key_file)
        g_key_file_free (extension->priv->key_file);
}

static void
midori_extension_set_property (GObject*      object,
                               guint         prop_id,
                               const GValue* value,
                               GParamSpec*   pspec)
{
    MidoriExtension* extension = MIDORI_EXTENSION (object);

    switch (prop_id)
    {
    case PROP_NAME:
        katze_assign (extension->priv->name, g_value_dup_string (value));
        break;
    case PROP_DESCRIPTION:
        katze_assign (extension->priv->description, g_value_dup_string (value));
        break;
    case PROP_VERSION:
        katze_assign (extension->priv->version, g_value_dup_string (value));
        break;
    case PROP_AUTHORS:
        katze_assign (extension->priv->authors, g_value_dup_string (value));
        break;
    default:
        G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
        break;
    }
}

static void
midori_extension_get_property (GObject*    object,
                               guint       prop_id,
                               GValue*     value,
                               GParamSpec* pspec)
{
    MidoriExtension* extension = MIDORI_EXTENSION (object);

    switch (prop_id)
    {
    case PROP_NAME:
        g_value_set_string (value, extension->priv->name);
        break;
    case PROP_DESCRIPTION:
        g_value_set_string (value, extension->priv->description);
        break;
    case PROP_VERSION:
        g_value_set_string (value, extension->priv->version);
        break;
    case PROP_AUTHORS:
        g_value_set_string (value, extension->priv->authors);
        break;
    default:
        G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
        break;
    }
}

/**
 * midori_extension_is_prepared:
 * @extension: a #MidoriExtension
 *
 * Determines if @extension is prepared for use, for instance
 * by ensuring that all required values are set and that it
 * is actually activatable.
 *
 * Return value: %TRUE if @extension is ready for use
 **/
gboolean
midori_extension_is_prepared (MidoriExtension* extension)
{
    g_return_val_if_fail (MIDORI_IS_EXTENSION (extension), FALSE);

    if (extension->priv->name && extension->priv->description
        && extension->priv->version && extension->priv->authors
        && g_signal_has_handler_pending (extension, signals[ACTIVATE], 0, FALSE))
        return TRUE;
    return FALSE;
}

/**
 * midori_extension_is_active:
 * @extension: a #MidoriExtension
 *
 * Determines if @extension is active.
 *
 * Return value: %TRUE if @extension is active
 *
 * Since: 0.1.2
 **/
gboolean
midori_extension_is_active (MidoriExtension* extension)
{
    g_return_val_if_fail (MIDORI_IS_EXTENSION (extension), FALSE);

    return extension->priv->active;
}

/**
 * midori_extension_deactivate:
 * @extension: a #MidoriExtension
 *
 * Attempts to deactivate @extension in a way that the instance
 * is actually finished irreversibly.
 **/
void
midori_extension_deactivate (MidoriExtension* extension)
{
    g_return_if_fail (MIDORI_IS_EXTENSION (extension));

    extension->priv->active = FALSE;
    g_signal_emit (extension, signals[DEACTIVATE], 0);
}

/**
 * midori_extension_get_config_dir:
 * @extension: a #MidoriExtension
 *
 * Retrieves the path to a directory reserved for configuration
 * files specific to the extension. For that purpose the 'name'
 * of the extension is actually part of the path.
 *
 * If settings are installed on the extension, they will be
 * loaded from and saved to a file "config" in this path.
 *
 * Return value: a path, such as ~/.config/midori/extensions/name
 **/
const gchar*
midori_extension_get_config_dir (MidoriExtension* extension)
{
    g_return_val_if_fail (midori_extension_is_prepared (extension), NULL);

    if (!extension->priv->config_dir)
        extension->priv->config_dir = g_build_filename (
            g_get_user_config_dir (), PACKAGE_NAME, "extensions",
            extension->priv->name, NULL);

    return extension->priv->config_dir;
}

/**
 * midori_extension_install_boolean:
 * @extension: a #MidoriExtension
 * @name: the name of the setting
 * @default_value: the default value
 *
 * Installs a boolean that can be used to conveniently
 * store user configuration.
 *
 * Note that all settings have to be installed before
 * the extension is activated.
 *
 * Since: 0.1.3
 **/
void
midori_extension_install_boolean (MidoriExtension* extension,
                                  const gchar*     name,
                                  gboolean         default_value)
{
    MESettingBoolean* setting;

    g_return_if_fail (midori_extension_is_prepared (extension));
    midori_extension_can_install_setting (extension, name);

    me_setting_install (MESettingBoolean, g_strdup (name), G_TYPE_BOOLEAN,
                        default_value, FALSE);
}

/**
 * midori_extension_get_boolean:
 * @extension: a #MidoriExtension
 * @name: the name of the setting
 *
 * Retrieves the value of the specified setting.
 *
 * Since: 0.1.3
 **/
gboolean
midori_extension_get_boolean (MidoriExtension* extension,
                              const gchar*     name)
{
    MESettingBoolean* setting;

    g_return_val_if_fail (midori_extension_is_prepared (extension), FALSE);
    g_return_val_if_fail (name != NULL, FALSE);

    setting = g_hash_table_lookup (extension->priv->settings, name);

    me_setting_type (setting, G_TYPE_BOOLEAN, return FALSE);

    return setting->value;
}

/**
 * midori_extension_set_boolean:
 * @extension: a #MidoriExtension
 * @name: the name of the setting
 * @value: the new value
 *
 * Assigns a new value to the specified setting.
 *
 * Since: 0.1.3
 **/
void
midori_extension_set_boolean (MidoriExtension* extension,
                              const gchar*     name,
                              gboolean         value)
{
    MESettingBoolean* setting;

    g_return_if_fail (midori_extension_is_active (extension));
    g_return_if_fail (name != NULL);

    setting = g_hash_table_lookup (extension->priv->settings, name);

    me_setting_type (setting, G_TYPE_BOOLEAN, return);

    setting->value = value;
    if (extension->priv->key_file)
    {
        GError* error = NULL;
        /* FIXME: Handle readonly folder/ file */
        gchar* config_file = g_build_filename (extension->priv->config_dir,
                                               "config", NULL);
        g_mkdir_with_parents (extension->priv->config_dir, 0700);
        g_key_file_set_boolean (extension->priv->key_file,
                                "settings", name, value);
        sokoke_key_file_save_to_file (extension->priv->key_file, config_file, &error);
        if (error)
        {
            printf (_("The configuration of the extension '%s' couldn't be saved: %s\n"),
                    extension->priv->name, error->message);
            g_error_free (error);
        }
    }
}

/**
 * midori_extension_install_integer:
 * @extension: a #MidoriExtension
 * @name: the name of the setting
 * @default_value: the default value
 *
 * Installs an integer that can be used to conveniently
 * store user configuration.
 *
 * Note that all settings have to be installed before
 * the extension is activated.
 *
 * Since: 0.1.3
 **/
void
midori_extension_install_integer (MidoriExtension* extension,
                                  const gchar*     name,
                                  gint             default_value)
{
    MESettingInteger* setting;

    g_return_if_fail (midori_extension_is_prepared (extension));
    midori_extension_can_install_setting (extension, name);

    me_setting_install (MESettingInteger, g_strdup (name), G_TYPE_INT,
                        default_value, 0);
}

/**
 * midori_extension_get_integer:
 * @extension: a #MidoriExtension
 * @name: the name of the setting
 *
 * Retrieves the value of the specified setting.
 *
 * Since: 0.1.3
 **/
gint
midori_extension_get_integer (MidoriExtension* extension,
                              const gchar*     name)
{
    MESettingInteger* setting;

    g_return_val_if_fail (midori_extension_is_prepared (extension), 0);
    g_return_val_if_fail (name != NULL, 0);

    setting = g_hash_table_lookup (extension->priv->settings, name);

    me_setting_type (setting, G_TYPE_INT, return 0);

    return setting->value;
}

/**
 * midori_extension_set_integer:
 * @extension: a #MidoriExtension
 * @name: the name of the setting
 * @value: the new value
 *
 * Assigns a new value to the specified setting.
 *
 * Since: 0.1.3
 **/
void
midori_extension_set_integer (MidoriExtension* extension,
                              const gchar*     name,
                              gint             value)
{
    MESettingInteger* setting;

    g_return_if_fail (midori_extension_is_active (extension));
    g_return_if_fail (name != NULL);

    setting = g_hash_table_lookup (extension->priv->settings, name);

    me_setting_type (setting, G_TYPE_INT, return);

    setting->value = value;
    if (extension->priv->key_file)
    {
        GError* error = NULL;
        /* FIXME: Handle readonly folder/ file */
        gchar* config_file = g_build_filename (extension->priv->config_dir,
                                               "config", NULL);
        g_mkdir_with_parents (extension->priv->config_dir, 0700);
        g_key_file_set_integer (extension->priv->key_file,
                                "settings", name, value);
        sokoke_key_file_save_to_file (extension->priv->key_file, config_file, &error);
        if (error)
        {
            printf (_("The configuration of the extension '%s' couldn't be saved: %s\n"),
                    extension->priv->name, error->message);
            g_error_free (error);
        }
    }
}

/**
 * midori_extension_install_string:
 * @extension: a #MidoriExtension
 * @name: the name of the setting
 * @default_value: the default value
 *
 * Installs a string that can be used to conveniently
 * store user configuration.
 *
 * Note that all settings have to be installed before
 * the extension is activated.
 *
 * Since: 0.1.3
 **/
void
midori_extension_install_string (MidoriExtension* extension,
                                 const gchar*     name,
                                 const gchar*     default_value)
{
    MESettingString* setting;

    g_return_if_fail (midori_extension_is_prepared (extension));
    midori_extension_can_install_setting (extension, name);

    me_setting_install (MESettingString, g_strdup (name), G_TYPE_STRING,
                        g_strdup (default_value), NULL);
}

/**
 * midori_extension_get_string:
 * @extension: a #MidoriExtension
 * @name: the name of the setting
 *
 * Retrieves the value of the specified setting.
 *
 * Since: 0.1.3
 **/
const gchar*
midori_extension_get_string (MidoriExtension* extension,
                             const gchar*     name)
{
    MESettingString* setting;

    g_return_val_if_fail (midori_extension_is_prepared (extension), NULL);
    g_return_val_if_fail (name != NULL, NULL);

    setting = g_hash_table_lookup (extension->priv->settings, name);

    me_setting_type (setting, G_TYPE_STRING, return NULL);

    return setting->value;
}

/**
 * midori_extension_set_string:
 * @extension: a #MidoriExtension
 * @name: the name of the setting
 * @value: the new value
 *
 * Assigns a new value to the specified setting.
 *
 * Since: 0.1.3
 **/
void
midori_extension_set_string (MidoriExtension* extension,
                             const gchar*     name,
                             const gchar*     value)
{
    MESettingString* setting;

    g_return_if_fail (midori_extension_is_active (extension));
    g_return_if_fail (name != NULL);

    setting = g_hash_table_lookup (extension->priv->settings, name);

    me_setting_type (setting, G_TYPE_STRING, return);

    katze_assign (setting->value, g_strdup (value));
    if (extension->priv->key_file)
    {
        GError* error = NULL;
        /* FIXME: Handle readonly folder/ file */
        gchar* config_file = g_build_filename (extension->priv->config_dir,
                                               "config", NULL);
        g_mkdir_with_parents (extension->priv->config_dir, 0700);
        g_key_file_set_string (extension->priv->key_file,
                                "settings", name, value);
        sokoke_key_file_save_to_file (extension->priv->key_file, config_file, &error);
        if (error)
        {
            printf (_("The configuration of the extension '%s' couldn't be saved: %s\n"),
                    extension->priv->name, error->message);
            g_error_free (error);
        }
    }
}