/*
* Copyright © 2010 Codethink Limited
*
* 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.
*
* 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General
* Public License along with this library; if not, see <http://www.gnu.org/licenses/>.
*
* Authors: Ryan Lortie <desrt@desrt.ca>
*/
#include "config.h"
#include "gaction.h"
#include "glibintl.h"
#include <string.h>
G_DEFINE_INTERFACE (GAction, g_action, G_TYPE_OBJECT)
/**
* SECTION:gaction
* @title: GAction
* @short_description: An action interface
* @include: gio/gio.h
*
* #GAction represents a single named action.
*
* The main interface to an action is that it can be activated with
* g_action_activate(). This results in the 'activate' signal being
* emitted. An activation has a #GVariant parameter (which may be
* %NULL). The correct type for the parameter is determined by a static
* parameter type (which is given at construction time).
*
* An action may optionally have a state, in which case the state may be
* set with g_action_change_state(). This call takes a #GVariant. The
* correct type for the state is determined by a static state type
* (which is given at construction time).
*
* The state may have a hint associated with it, specifying its valid
* range.
*
* #GAction is merely the interface to the concept of an action, as
* described above. Various implementations of actions exist, including
* #GSimpleAction.
*
* In all cases, the implementing class is responsible for storing the
* name of the action, the parameter type, the enabled state, the
* optional state type and the state and emitting the appropriate
* signals when these change. The implementor is responsible for filtering
* calls to g_action_activate() and g_action_change_state() for type
* safety and for the state being enabled.
*
* Probably the only useful thing to do with a #GAction is to put it
* inside of a #GSimpleActionGroup.
**/
/**
* GAction:
*
* #GAction is an opaque data structure and can only be accessed
* using the following functions.
**/
/**
* GActionInterface:
* @get_name: the virtual function pointer for g_action_get_name()
* @get_parameter_type: the virtual function pointer for g_action_get_parameter_type()
* @get_state_type: the virtual function pointer for g_action_get_state_type()
* @get_state_hint: the virtual function pointer for g_action_get_state_hint()
* @get_enabled: the virtual function pointer for g_action_get_enabled()
* @get_state: the virtual function pointer for g_action_get_state()
* @change_state: the virtual function pointer for g_action_change_state()
* @activate: the virtual function pointer for g_action_activate(). Note that #GAction does not have an
* 'activate' signal but that implementations of it may have one.
*
* The virtual function table for #GAction.
*
* Since: 2.28
*/
void
g_action_default_init (GActionInterface *iface)
{
/**
* GAction:name:
*
* The name of the action. This is mostly meaningful for identifying
* the action once it has been added to a #GActionGroup. It is immutable.
*
* Since: 2.28
**/
g_object_interface_install_property (iface,
g_param_spec_string ("name",
P_("Action Name"),
P_("The name used to invoke the action"),
NULL,
G_PARAM_READABLE |
G_PARAM_STATIC_STRINGS));
/**
* GAction:parameter-type:
*
* The type of the parameter that must be given when activating the
* action. This is immutable, and may be %NULL if no parameter is needed when
* activating the action.
*
* Since: 2.28
**/
g_object_interface_install_property (iface,
g_param_spec_boxed ("parameter-type",
P_("Parameter Type"),
P_("The type of GVariant passed to activate()"),
G_TYPE_VARIANT_TYPE,
G_PARAM_READABLE |
G_PARAM_STATIC_STRINGS));
/**
* GAction:enabled:
*
* If @action is currently enabled.
*
* If the action is disabled then calls to g_action_activate() and
* g_action_change_state() have no effect.
*
* Since: 2.28
**/
g_object_interface_install_property (iface,
g_param_spec_boolean ("enabled",
P_("Enabled"),
P_("If the action can be activated"),
TRUE,
G_PARAM_READABLE |
G_PARAM_STATIC_STRINGS));
/**
* GAction:state-type:
*
* The #GVariantType of the state that the action has, or %NULL if the
* action is stateless. This is immutable.
*
* Since: 2.28
**/
g_object_interface_install_property (iface,
g_param_spec_boxed ("state-type",
P_("State Type"),
P_("The type of the state kept by the action"),
G_TYPE_VARIANT_TYPE,
G_PARAM_READABLE |
G_PARAM_STATIC_STRINGS));
/**
* GAction:state:
*
* The state of the action, or %NULL if the action is stateless.
*
* Since: 2.28
**/
g_object_interface_install_property (iface,
g_param_spec_variant ("state",
P_("State"),
P_("The state the action is in"),
G_VARIANT_TYPE_ANY,
NULL,
G_PARAM_READABLE |
G_PARAM_STATIC_STRINGS));
}
/**
* g_action_change_state:
* @action: a #GAction
* @value: the new state
*
* Request for the state of @action to be changed to @value.
*
* The action must be stateful and @value must be of the correct type.
* See g_action_get_state_type().
*
* This call merely requests a change. The action may refuse to change
* its state or may change its state to something other than @value.
* See g_action_get_state_hint().
*
* If the @value GVariant is floating, it is consumed.
*
* Since: 2.30
**/
void
g_action_change_state (GAction *action,
GVariant *value)
{
const GVariantType *state_type;
g_return_if_fail (G_IS_ACTION (action));
g_return_if_fail (value != NULL);
state_type = g_action_get_state_type (action);
g_return_if_fail (state_type != NULL);
g_return_if_fail (g_variant_is_of_type (value, state_type));
g_variant_ref_sink (value);
G_ACTION_GET_IFACE (action)
->change_state (action, value);
g_variant_unref (value);
}
/**
* g_action_get_state:
* @action: a #GAction
*
* Queries the current state of @action.
*
* If the action is not stateful then %NULL will be returned. If the
* action is stateful then the type of the return value is the type
* given by g_action_get_state_type().
*
* The return value (if non-%NULL) should be freed with
* g_variant_unref() when it is no longer required.
*
* Returns: (transfer full): the current state of the action
*
* Since: 2.28
**/
GVariant *
g_action_get_state (GAction *action)
{
g_return_val_if_fail (G_IS_ACTION (action), NULL);
return G_ACTION_GET_IFACE (action)
->get_state (action);
}
/**
* g_action_get_name:
* @action: a #GAction
*
* Queries the name of @action.
*
* Returns: the name of the action
*
* Since: 2.28
**/
const gchar *
g_action_get_name (GAction *action)
{
g_return_val_if_fail (G_IS_ACTION (action), NULL);
return G_ACTION_GET_IFACE (action)
->get_name (action);
}
/**
* g_action_get_parameter_type:
* @action: a #GAction
*
* Queries the type of the parameter that must be given when activating
* @action.
*
* When activating the action using g_action_activate(), the #GVariant
* given to that function must be of the type returned by this function.
*
* In the case that this function returns %NULL, you must not give any
* #GVariant, but %NULL instead.
*
* Returns: (nullable): the parameter type
*
* Since: 2.28
**/
const GVariantType *
g_action_get_parameter_type (GAction *action)
{
g_return_val_if_fail (G_IS_ACTION (action), NULL);
return G_ACTION_GET_IFACE (action)
->get_parameter_type (action);
}
/**
* g_action_get_state_type:
* @action: a #GAction
*
* Queries the type of the state of @action.
*
* If the action is stateful (e.g. created with
* g_simple_action_new_stateful()) then this function returns the
* #GVariantType of the state. This is the type of the initial value
* given as the state. All calls to g_action_change_state() must give a
* #GVariant of this type and g_action_get_state() will return a
* #GVariant of the same type.
*
* If the action is not stateful (e.g. created with g_simple_action_new())
* then this function will return %NULL. In that case, g_action_get_state()
* will return %NULL and you must not call g_action_change_state().
*
* Returns: (nullable): the state type, if the action is stateful
*
* Since: 2.28
**/
const GVariantType *
g_action_get_state_type (GAction *action)
{
g_return_val_if_fail (G_IS_ACTION (action), NULL);
return G_ACTION_GET_IFACE (action)
->get_state_type (action);
}
/**
* g_action_get_state_hint:
* @action: a #GAction
*
* Requests a hint about the valid range of values for the state of
* @action.
*
* If %NULL is returned it either means that the action is not stateful
* or that there is no hint about the valid range of values for the
* state of the action.
*
* If a #GVariant array is returned then each item in the array is a
* possible value for the state. If a #GVariant pair (ie: two-tuple) is
* returned then the tuple specifies the inclusive lower and upper bound
* of valid values for the state.
*
* In any case, the information is merely a hint. It may be possible to
* have a state value outside of the hinted range and setting a value
* within the range may fail.
*
* The return value (if non-%NULL) should be freed with
* g_variant_unref() when it is no longer required.
*
* Returns: (nullable) (transfer full): the state range hint
*
* Since: 2.28
**/
GVariant *
g_action_get_state_hint (GAction *action)
{
g_return_val_if_fail (G_IS_ACTION (action), NULL);
return G_ACTION_GET_IFACE (action)
->get_state_hint (action);
}
/**
* g_action_get_enabled:
* @action: a #GAction
*
* Checks if @action is currently enabled.
*
* An action must be enabled in order to be activated or in order to
* have its state changed from outside callers.
*
* Returns: whether the action is enabled
*
* Since: 2.28
**/
gboolean
g_action_get_enabled (GAction *action)
{
g_return_val_if_fail (G_IS_ACTION (action), FALSE);
return G_ACTION_GET_IFACE (action)
->get_enabled (action);
}
/**
* g_action_activate:
* @action: a #GAction
* @parameter: (nullable): the parameter to the activation
*
* Activates the action.
*
* @parameter must be the correct type of parameter for the action (ie:
* the parameter type given at construction time). If the parameter
* type was %NULL then @parameter must also be %NULL.
*
* If the @parameter GVariant is floating, it is consumed.
*
* Since: 2.28
**/
void
g_action_activate (GAction *action,
GVariant *parameter)
{
g_return_if_fail (G_IS_ACTION (action));
if (parameter != NULL)
g_variant_ref_sink (parameter);
G_ACTION_GET_IFACE (action)
->activate (action, parameter);
if (parameter != NULL)
g_variant_unref (parameter);
}
/**
* g_action_name_is_valid:
* @action_name: an potential action name
*
* Checks if @action_name is valid.
*
* @action_name is valid if it consists only of alphanumeric characters,
* plus '-' and '.'. The empty string is not a valid action name.
*
* It is an error to call this function with a non-utf8 @action_name.
* @action_name must not be %NULL.
*
* Returns: %TRUE if @action_name is valid
*
* Since: 2.38
**/
gboolean
g_action_name_is_valid (const gchar *action_name)
{
gchar c;
gint i;
g_return_val_if_fail (action_name != NULL, FALSE);
for (i = 0; (c = action_name[i]); i++)
if (!g_ascii_isalnum (c) && c != '.' && c != '-')
return FALSE;
return i > 0;
}
/**
* g_action_parse_detailed_name:
* @detailed_name: a detailed action name
* @action_name: (out): the action name
* @target_value: (out): the target value, or %NULL for no target
* @error: a pointer to a %NULL #GError, or %NULL
*
* Parses a detailed action name into its separate name and target
* components.
*
* Detailed action names can have three formats.
*
* The first format is used to represent an action name with no target
* value and consists of just an action name containing no whitespace
* nor the characters ':', '(' or ')'. For example: "app.action".
*
* The second format is used to represent an action with a target value
* that is a non-empty string consisting only of alphanumerics, plus '-'
* and '.'. In that case, the action name and target value are
* separated by a double colon ("::"). For example:
* "app.action::target".
*
* The third format is used to represent an action with any type of
* target value, including strings. The target value follows the action
* name, surrounded in parens. For example: "app.action(42)". The
* target value is parsed using g_variant_parse(). If a tuple-typed
* value is desired, it must be specified in the same way, resulting in
* two sets of parens, for example: "app.action((1,2,3))". A string
* target can be specified this way as well: "app.action('target')".
* For strings, this third format must be used if * target value is
* empty or contains characters other than alphanumerics, '-' and '.'.
*
* Returns: %TRUE if successful, else %FALSE with @error set
*
* Since: 2.38
**/
gboolean
g_action_parse_detailed_name (const gchar *detailed_name,
gchar **action_name,
GVariant **target_value,
GError **error)
{
const gchar *target;
gsize target_len;
gsize base_len;
/* For historical (compatibility) reasons, this function accepts some
* cases of invalid action names as long as they don't interfere with
* the separation of the action from the target value.
*
* We decide which format we have based on which we see first between
* '::' '(' and '\0'.
*/
if (*detailed_name == '\0' || *detailed_name == ' ')
goto bad_fmt;
base_len = strcspn (detailed_name, ": ()");
target = detailed_name + base_len;
target_len = strlen (target);
switch (target[0])
{
case ' ':
case ')':
goto bad_fmt;
case ':':
if (target[1] != ':')
goto bad_fmt;
*target_value = g_variant_ref_sink (g_variant_new_string (target + 2));
break;
case '(':
{
if (target[target_len - 1] != ')')
goto bad_fmt;
*target_value = g_variant_parse (NULL, target + 1, target + target_len - 1, NULL, error);
if (*target_value == NULL)
goto bad_fmt;
}
break;
case '\0':
*target_value = NULL;
break;
}
*action_name = g_strndup (detailed_name, base_len);
return TRUE;
bad_fmt:
if (error)
{
if (*error == NULL)
g_set_error (error, G_VARIANT_PARSE_ERROR, G_VARIANT_PARSE_ERROR_FAILED,
"Detailed action name '%s' has invalid format", detailed_name);
else
g_prefix_error (error, "Detailed action name '%s' has invalid format: ", detailed_name);
}
return FALSE;
}
/**
* g_action_print_detailed_name:
* @action_name: a valid action name
* @target_value: (nullable): a #GVariant target value, or %NULL
*
* Formats a detailed action name from @action_name and @target_value.
*
* It is an error to call this function with an invalid action name.
*
* This function is the opposite of g_action_parse_detailed_name().
* It will produce a string that can be parsed back to the @action_name
* and @target_value by that function.
*
* See that function for the types of strings that will be printed by
* this function.
*
* Returns: a detailed format string
*
* Since: 2.38
**/
gchar *
g_action_print_detailed_name (const gchar *action_name,
GVariant *target_value)
{
g_return_val_if_fail (g_action_name_is_valid (action_name), NULL);
if (target_value == NULL)
return g_strdup (action_name);
if (g_variant_is_of_type (target_value, G_VARIANT_TYPE_STRING))
{
const gchar *str = g_variant_get_string (target_value, NULL);
if (g_action_name_is_valid (str))
return g_strconcat (action_name, "::", str, NULL);
}
{
GString *result = g_string_new (action_name);
g_string_append_c (result, '(');
g_variant_print_string (target_value, result, TRUE);
g_string_append_c (result, ')');
return g_string_free (result, FALSE);
}
}