bindsym/code: add group support

This adds support for specifying a binding for a specific group. Any
binding without a group listed will be available in all groups. The
priority for matching bindings is as follows: input device, group, and
locked state.

For full compatibility with i3, this also adds Mode_switch as an alias
for Group2. Since i3 only supports this for backwards compatibility
with older versions of i3, it is implemented here, but not documented.

4 files changed, 76 insertions, 15 deletions

diff --git a/include/sway/config.h b/include/sway/config.h
index f1426453a..c65d93533 100644
--- a/include/sway/config.h
+++ b/include/sway/config.h
@@ -53,6 +53,7 @@ struct sway_binding {
 	list_t *keys; // sorted in ascending order
 	list_t *syms; // sorted in ascending order; NULL if BINDING_CODE is not set
 	uint32_t modifiers;
+	xkb_layout_index_t group;
 	char *command;
 };
 
diff --git a/sway/commands/bind.c b/sway/commands/bind.c
index 767c2fee1..5ec899826 100644
--- a/sway/commands/bind.c
+++ b/sway/commands/bind.c
@@ -78,6 +78,10 @@ static bool binding_key_compare(struct sway_binding *binding_a,
 		return false;
 	}
 
+	if (binding_a->group != binding_b->group) {
+		return false;
+	}
+
 	if (binding_a->modifiers ^ binding_b->modifiers) {
 		return false;
 	}
@@ -337,6 +341,7 @@ static struct cmd_results *cmd_bindsym_or_bindcode(int argc, char **argv,
 	}
 	binding->input = strdup("*");
 	binding->keys = create_list();
+	binding->group = XKB_LAYOUT_INVALID;
 	binding->modifiers = 0;
 	binding->flags = 0;
 	binding->type = bindcode ? BINDING_KEYCODE : BINDING_KEYSYM;
@@ -387,6 +392,34 @@ static struct cmd_results *cmd_bindsym_or_bindcode(int argc, char **argv,
 
 	list_t *split = split_string(argv[0], "+");
 	for (int i = 0; i < split->length; ++i) {
+		// Check for group
+		if (strncmp(split->items[i], "Group", strlen("Group")) == 0) {
+			if (binding->group != XKB_LAYOUT_INVALID) {
+				free_sway_binding(binding);
+				list_free_items_and_destroy(split);
+				return cmd_results_new(CMD_FAILURE,
+						"Only one group can be specified");
+			}
+			char *end;
+			int group = strtol(split->items[i] + strlen("Group"), &end, 10);
+			if (group < 1 || group > 4 || end[0] != '\0') {
+				free_sway_binding(binding);
+				list_free_items_and_destroy(split);
+				return cmd_results_new(CMD_FAILURE, "Invalid group");
+			}
+			binding->group = group - 1;
+			continue;
+		} else if (strcmp(split->items[i], "Mode_switch") == 0) {
+			// For full i3 compatibility, Mode_switch is an alias for Group2
+			if (binding->group != XKB_LAYOUT_INVALID) {
+				free_sway_binding(binding);
+				list_free_items_and_destroy(split);
+				return cmd_results_new(CMD_FAILURE,
+						"Only one group can be specified");
+			}
+			binding->group = 1;
+		}
+
 		// Check for a modifier key
 		uint32_t mod;
 		if ((mod = get_modifier_mask_by_name(split->items[i])) > 0) {
diff --git a/sway/input/keyboard.c b/sway/input/keyboard.c
index aecabbf43..680d1f693 100644
--- a/sway/input/keyboard.c
+++ b/sway/input/keyboard.c
@@ -143,7 +143,8 @@ static void update_shortcut_state(struct sway_shortcut_state *state,
  */
 static void get_active_binding(const struct sway_shortcut_state *state,
 		list_t *bindings, struct sway_binding **current_binding,
-		uint32_t modifiers, bool release, bool locked, const char *input) {
+		uint32_t modifiers, bool release, bool locked, const char *input,
+		xkb_layout_index_t group) {
 	for (int i = 0; i < bindings->length; ++i) {
 		struct sway_binding *binding = bindings->items[i];
 		bool binding_locked = (binding->flags & BINDING_LOCKED) != 0;
@@ -152,6 +153,8 @@ static void get_active_binding(const struct sway_shortcut_state *state,
 		if (modifiers ^ binding->modifiers ||
 				release != binding_release ||
 				locked > binding_locked ||
+				(binding->group != XKB_LAYOUT_INVALID &&
+				 binding->group != group) ||
 				(strcmp(binding->input, input) != 0 &&
 				 strcmp(binding->input, "*") != 0)) {
 			continue;
@@ -186,10 +189,14 @@ static void get_active_binding(const struct sway_shortcut_state *state,
 			bool current_locked =
 				((*current_binding)->flags & BINDING_LOCKED) != 0;
 			bool current_input = strcmp((*current_binding)->input, input) == 0;
+			bool current_group_set =
+				(*current_binding)->group != XKB_LAYOUT_INVALID;
 			bool binding_input = strcmp(binding->input, input) == 0;
+			bool binding_group_set = binding->group != XKB_LAYOUT_INVALID;
 
 			if (current_input == binding_input
-					&& current_locked == binding_locked) {
+					&& current_locked == binding_locked
+					&& current_group_set == binding_group_set) {
 				sway_log(SWAY_DEBUG,
 						"Encountered conflicting bindings %d and %d",
 						(*current_binding)->order, binding->order);
@@ -200,14 +207,22 @@ static void get_active_binding(const struct sway_shortcut_state *state,
 				continue; // Prefer the correct input
 			}
 
-			if (current_input == binding_input && current_locked == locked) {
-				continue; // Prefer correct lock state for matching inputs
+			if (current_input == binding_input &&
+				   (*current_binding)->group == group) {
+				continue; // Prefer correct group for matching inputs
+			}
+
+			if (current_input == binding_input &&
+					current_group_set == binding_group_set &&
+					current_locked == locked) {
+				continue; // Prefer correct lock state for matching input+group
 			}
 		}
 
 		*current_binding = binding;
 		if (strcmp((*current_binding)->input, input) == 0 &&
-				(((*current_binding)->flags & BINDING_LOCKED) == locked)) {
+				(((*current_binding)->flags & BINDING_LOCKED) == locked) &&
+				(*current_binding)->group == group) {
 			return; // If a perfect match is found, quit searching
 		}
 	}
@@ -344,13 +359,16 @@ static void handle_keyboard_key(struct wl_listener *listener, void *data) {
 	struct sway_binding *binding_released = NULL;
 	get_active_binding(&keyboard->state_keycodes,
 			config->current_mode->keycode_bindings, &binding_released,
-			code_modifiers, true, input_inhibited, device_identifier);
+			code_modifiers, true, input_inhibited, device_identifier,
+			keyboard->effective_layout);
 	get_active_binding(&keyboard->state_keysyms_raw,
 			config->current_mode->keysym_bindings, &binding_released,
-			raw_modifiers, true, input_inhibited, device_identifier);
+			raw_modifiers, true, input_inhibited, device_identifier,
+			keyboard->effective_layout);
 	get_active_binding(&keyboard->state_keysyms_translated,
 			config->current_mode->keysym_bindings, &binding_released,
-			translated_modifiers, true, input_inhibited, device_identifier);
+			translated_modifiers, true, input_inhibited, device_identifier,
+			keyboard->effective_layout);
 
 	// Execute stored release binding once no longer active
 	if (keyboard->held_binding && binding_released != keyboard->held_binding &&
@@ -370,14 +388,16 @@ static void handle_keyboard_key(struct wl_listener *listener, void *data) {
 	if (event->state == WLR_KEY_PRESSED) {
 		get_active_binding(&keyboard->state_keycodes,
 				config->current_mode->keycode_bindings, &binding,
-				code_modifiers, false, input_inhibited, device_identifier);
+				code_modifiers, false, input_inhibited, device_identifier,
+				keyboard->effective_layout);
 		get_active_binding(&keyboard->state_keysyms_raw,
 				config->current_mode->keysym_bindings, &binding,
-				raw_modifiers, false, input_inhibited, device_identifier);
+				raw_modifiers, false, input_inhibited, device_identifier,
+				keyboard->effective_layout);
 		get_active_binding(&keyboard->state_keysyms_translated,
 				config->current_mode->keysym_bindings, &binding,
 				translated_modifiers, false, input_inhibited,
-				device_identifier);
+				device_identifier, keyboard->effective_layout);
 	}
 
 	// Set up (or clear) keyboard repeat for a pressed binding. Since the
diff --git a/sway/sway.5.scd b/sway/sway.5.scd
index ac80de3c9..3e445e0e2 100644
--- a/sway/sway.5.scd
+++ b/sway/sway.5.scd
@@ -328,14 +328,17 @@ runtime.
 
 		for_window <criteria> move container to output <output>
 
-*bindsym* [--whole-window] [--border] [--exclude-titlebar] [--release] [--locked] [--to-code] [--input-device=<device>] [--no-warn] <key combo> <command>
+*bindsym* [--whole-window] [--border] [--exclude-titlebar] [--release] [--locked] \
+		[--to-code] [--input-device=<device>] [--no-warn] [Group<1-4>+]<key combo> \
+		<command>
 	Binds _key combo_ to execute the sway command _command_ when pressed. You
 	may use XKB key names here (*xev*(1) is a good tool for discovering these).
 	With the flag _--release_, the command is executed when the key combo is
 	released. If _input-device_ is given, the binding will only be executed for
 	that input device and will be executed instead of any binding that is
-	generic to all devices. By default, if you overwrite a binding, swaynag
-	will give you a warning. To silence this, use the _--no-warn_ flag.
+	generic to all devices. If a group number is given, then the binding will
+	only be available for that group. By default, if you overwrite a binding,
+	swaynag will give you a warning. To silence this, use the _--no-warn_ flag.
 
 	Unless the flag _--locked_ is set, the command will not be run when a
 	screen locking program is active. If there is a matching binding with
@@ -356,6 +359,9 @@ runtime.
 	6=scroll left, 7=scroll right, 8=back, 9=forward). For the latter option,
 	you can find the event names using _libinput debug-events_.
 
+	The priority for matching bindings is as follows: input device, group,
+	and locked state.
+
 	_--whole-window_, _--border_, and _--exclude-titlebar_ are mouse-only options
 	which affect the region in which the mouse bindings can be triggered.  By
 	default, mouse bindings are only triggered when over the title bar. With the
@@ -375,7 +381,8 @@ runtime.
 		bindsym Mod1+Shift+f exec firefox
 ```
 
-	*bindcode* [--whole-window] [--border] [--exclude-titlebar] [--release] [--locked] [--input-device=<device>] [--no-warn] <code> <command>
+	*bindcode* [--whole-window] [--border] [--exclude-titlebar] [--release] \
+	[--locked] [--input-device=<device>] [--no-warn] [Group<1-4>+]<code> <command>
 	is also available for binding with key/button codes instead of key/button names.
 
 *bindswitch* [--locked] [--no-warn] [--reload] <switch>:<state> <command>