Port input method and text input from rootston

This ports swaywm/wlroots#1203, swaywm/wlroots#1303,
swaywm/wlroots#1308, swaywm/wlroots#1759 rootston part to sway.

Co-Authored-By: Leo Chen <leo881003@gmail.com>

include/sway/input/seat.h

@@ -7,6 +7,7 @@
 #include <wlr/util/edges.h>
 #include "sway/config.h"
 #include "sway/input/input-manager.h"
+#include "sway/input/text_input.h"
 
 struct sway_seat;
 
@@ -86,6 +87,8 @@ struct sway_seat {
 
 	list_t *deferred_bindings; // struct sway_binding
 
+	struct sway_input_method_relay im_relay;
+
 	struct wl_listener focus_destroy;
 	struct wl_listener new_node;
 	struct wl_listener request_start_drag;

include/sway/input/text_input.h

@@ -0,0 +1,63 @@
+#ifndef _SWAY_INPUT_TEXT_INPUT_H
+#define _SWAY_INPUT_TEXT_INPUT_H
+
+#include <wlr/types/wlr_text_input_v3.h>
+#include <wlr/types/wlr_input_method_v2.h>
+#include <wlr/types/wlr_surface.h>
+#include "sway/input/seat.h"
+
+/**
+ * The relay structure manages the relationship between text-input and
+ * input_method interfaces on a given seat. Multiple text-input interfaces may
+ * be bound to a relay, but at most one will be focused (reveiving events) at
+ * a time. At most one input-method interface may be bound to the seat. The
+ * relay manages life cycle of both sides. When both sides are present and
+ * focused, the relay passes messages between them.
+ *
+ * Text input focus is a subset of keyboard focus - if the text-input is
+ * in the focused state, wl_keyboard sent an enter as well. However, having
+ * wl_keyboard focused doesn't mean that text-input will be focused.
+ */
+struct sway_input_method_relay {
+	struct sway_seat *seat;
+
+	struct wl_list text_inputs; // sway_text_input::link
+	struct wlr_input_method_v2 *input_method; // doesn't have to be present
+
+	struct wl_listener text_input_new;
+	struct wl_listener text_input_enable;
+	struct wl_listener text_input_commit;
+	struct wl_listener text_input_disable;
+	struct wl_listener text_input_destroy;
+
+	struct wl_listener input_method_new;
+	struct wl_listener input_method_commit;
+	struct wl_listener input_method_destroy;
+};
+
+struct sway_text_input {
+	struct sway_input_method_relay *relay;
+
+	struct wlr_text_input_v3 *input;
+	// The surface getting seat's focus. Stored for when text-input cannot
+	// be sent an enter event immediately after getting focus, e.g. when
+	// there's no input method available. Cleared once text-input is entered.
+	struct wlr_surface *pending_focused_surface;
+
+	struct wl_list link;
+
+	struct wl_listener pending_focused_surface_destroy;
+};
+
+void sway_input_method_relay_init(struct sway_seat *seat,
+	struct sway_input_method_relay *relay);
+
+// Updates currently focused surface. Surface must belong to the same seat.
+void sway_input_method_relay_set_focus(struct sway_input_method_relay *relay,
+	struct wlr_surface *surface);
+
+struct sway_text_input *sway_text_input_create(
+	struct sway_input_method_relay *relay,
+	struct wlr_text_input_v3 *text_input);
+
+#endif

include/sway/server.h

@@ -7,12 +7,14 @@
 #include <wlr/render/wlr_renderer.h>
 #include <wlr/types/wlr_compositor.h>
 #include <wlr/types/wlr_data_device.h>
+#include <wlr/types/wlr_input_method_v2.h>
 #include <wlr/types/wlr_layer_shell_v1.h>
 #include <wlr/types/wlr_output_management_v1.h>
 #include <wlr/types/wlr_output_power_management_v1.h>
 #include <wlr/types/wlr_presentation_time.h>
 #include <wlr/types/wlr_relative_pointer_v1.h>
 #include <wlr/types/wlr_server_decoration.h>
+#include <wlr/types/wlr_text_input_v3.h>
 #include <wlr/types/wlr_xdg_shell.h>
 #include "config.h"
 #include "list.h"
@@ -76,6 +78,8 @@ struct sway_server {
 
 	struct wlr_output_power_manager_v1 *output_power_manager_v1;
 	struct wl_listener output_power_manager_set_mode;
+	struct wlr_input_method_manager_v2 *input_method;
+	struct wlr_text_input_manager_v3 *text_input;
 
 	size_t txn_timeout_ms;
 	list_t *transactions;

sway/input/seat.c

@@ -179,6 +179,7 @@ static void seat_send_focus(struct sway_node *node, struct sway_seat *seat) {
 
 		seat_keyboard_notify_enter(seat, view->surface);
 		seat_tablet_pads_notify_enter(seat, view->surface);
+		sway_input_method_relay_set_focus(&seat->im_relay, view->surface);
 
 		struct wlr_pointer_constraint_v1 *constraint =
 			wlr_pointer_constraints_v1_constraint_for_surface(
@@ -562,6 +563,8 @@ struct sway_seat *seat_create(const char *seat_name) {
 	wl_list_init(&seat->keyboard_groups);
 	wl_list_init(&seat->keyboard_shortcuts_inhibitors);
 
+	sway_input_method_relay_init(seat, &seat->im_relay);
+
 	wl_list_insert(&server.input->seats, &seat->link);
 
 	seatop_begin_default(seat);
@@ -1015,6 +1018,7 @@ void seat_set_focus(struct sway_seat *seat, struct sway_node *node) {
 			view_close_popups(last_focus->sway_container->view);
 		}
 		seat_send_unfocus(last_focus, seat);
+		sway_input_method_relay_set_focus(&seat->im_relay, NULL);
 		seat->has_focus = false;
 		return;
 	}

sway/input/text_input.c

@@ -0,0 +1,312 @@
+#include <assert.h>
+#include <stdlib.h>
+#include "log.h"
+#include "sway/input/seat.h"
+#include "sway/input/text_input.h"
+
+static struct sway_text_input *relay_get_focusable_text_input(
+		struct sway_input_method_relay *relay) {
+	struct sway_text_input *text_input = NULL;
+	wl_list_for_each(text_input, &relay->text_inputs, link) {
+		if (text_input->pending_focused_surface) {
+			return text_input;
+		}
+	}
+	return NULL;
+}
+
+static struct sway_text_input *relay_get_focused_text_input(
+		struct sway_input_method_relay *relay) {
+	struct sway_text_input *text_input = NULL;
+	wl_list_for_each(text_input, &relay->text_inputs, link) {
+		if (text_input->input->focused_surface) {
+			return text_input;
+		}
+	}
+	return NULL;
+}
+
+static void handle_im_commit(struct wl_listener *listener, void *data) {
+	struct sway_input_method_relay *relay = wl_container_of(listener, relay,
+		input_method_commit);
+
+	struct sway_text_input *text_input = relay_get_focused_text_input(relay);
+	if (!text_input) {
+		return;
+	}
+	struct wlr_input_method_v2 *context = data;
+	assert(context == relay->input_method);
+	if (context->current.preedit.text) {
+		wlr_text_input_v3_send_preedit_string(text_input->input,
+			context->current.preedit.text,
+			context->current.preedit.cursor_begin,
+			context->current.preedit.cursor_end);
+	}
+	if (context->current.commit_text) {
+		wlr_text_input_v3_send_commit_string(text_input->input,
+			context->current.commit_text);
+	}
+	if (context->current.delete.before_length
+			|| context->current.delete.after_length) {
+		wlr_text_input_v3_send_delete_surrounding_text(text_input->input,
+			context->current.delete.before_length,
+			context->current.delete.after_length);
+	}
+	wlr_text_input_v3_send_done(text_input->input);
+}
+
+static void text_input_set_pending_focused_surface(
+		struct sway_text_input *text_input, struct wlr_surface *surface) {
+	text_input->pending_focused_surface = surface;
+	wl_signal_add(&surface->events.destroy,
+		&text_input->pending_focused_surface_destroy);
+}
+
+static void text_input_clear_pending_focused_surface(
+		struct sway_text_input *text_input) {
+	wl_list_remove(&text_input->pending_focused_surface_destroy.link);
+	wl_list_init(&text_input->pending_focused_surface_destroy.link);
+	text_input->pending_focused_surface = NULL;
+}
+
+static void handle_im_destroy(struct wl_listener *listener, void *data) {
+	struct sway_input_method_relay *relay = wl_container_of(listener, relay,
+		input_method_destroy);
+	struct wlr_input_method_v2 *context = data;
+	assert(context == relay->input_method);
+	relay->input_method = NULL;
+	struct sway_text_input *text_input = relay_get_focused_text_input(relay);
+	if (text_input) {
+		// keyboard focus is still there, so keep the surface at hand in case
+		// the input method returns
+		text_input_set_pending_focused_surface(text_input,
+			text_input->input->focused_surface);
+		wlr_text_input_v3_send_leave(text_input->input);
+	}
+}
+
+static void relay_send_im_state(struct sway_input_method_relay *relay,
+		struct wlr_text_input_v3 *input) {
+	struct wlr_input_method_v2 *input_method = relay->input_method;
+	if (!input_method) {
+		sway_log(SWAY_INFO, "Sending IM_DONE but im is gone");
+		return;
+	}
+	// TODO: only send each of those if they were modified
+	wlr_input_method_v2_send_surrounding_text(input_method,
+		input->current.surrounding.text, input->current.surrounding.cursor,
+		input->current.surrounding.anchor);
+	wlr_input_method_v2_send_text_change_cause(input_method,
+		input->current.text_change_cause);
+	wlr_input_method_v2_send_content_type(input_method,
+		input->current.content_type.hint, input->current.content_type.purpose);
+	wlr_input_method_v2_send_done(input_method);
+	// TODO: pass intent, display popup size
+}
+
+static struct sway_text_input *text_input_to_sway(
+		struct sway_input_method_relay *relay,
+		struct wlr_text_input_v3 *text_input) {
+	struct sway_text_input *sway_text_input = NULL;
+	wl_list_for_each(sway_text_input, &relay->text_inputs, link) {
+		if (sway_text_input->input == text_input) {
+			return sway_text_input;
+		}
+	}
+	return NULL;
+}
+
+static void handle_text_input_enable(struct wl_listener *listener, void *data) {
+	struct sway_input_method_relay *relay = wl_container_of(listener, relay,
+		text_input_enable);
+	if (relay->input_method == NULL) {
+		sway_log(SWAY_INFO, "Enabling text input when input method is gone");
+		return;
+	}
+	struct sway_text_input *text_input = text_input_to_sway(relay,
+		(struct wlr_text_input_v3*)data);
+	wlr_input_method_v2_send_activate(relay->input_method);
+	relay_send_im_state(relay, text_input->input);
+}
+
+static void handle_text_input_commit(struct wl_listener *listener,
+		void *data) {
+	struct sway_input_method_relay *relay = wl_container_of(listener, relay,
+		text_input_commit);
+	struct sway_text_input *text_input = text_input_to_sway(relay,
+		(struct wlr_text_input_v3*)data);
+	if (!text_input->input->current_enabled) {
+		sway_log(SWAY_INFO, "Inactive text input tried to commit an update");
+		return;
+	}
+	sway_log(SWAY_DEBUG, "Text input committed update");
+	if (relay->input_method == NULL) {
+		sway_log(SWAY_INFO, "Text input committed, but input method is gone");
+		return;
+	}
+	relay_send_im_state(relay, text_input->input);
+}
+
+static void relay_disable_text_input(struct sway_input_method_relay *relay,
+		struct sway_text_input *text_input) {
+	if (relay->input_method == NULL) {
+		sway_log(SWAY_DEBUG, "Disabling text input, but input method is gone");
+		return;
+	}
+	wlr_input_method_v2_send_deactivate(relay->input_method);
+	relay_send_im_state(relay, text_input->input);
+}
+
+static void handle_text_input_disable(struct wl_listener *listener,
+		void *data) {
+	struct sway_input_method_relay *relay = wl_container_of(listener, relay,
+		text_input_disable);
+	struct sway_text_input *text_input = text_input_to_sway(relay,
+		(struct wlr_text_input_v3*)data);
+	relay_disable_text_input(relay, text_input);
+}
+
+static void handle_text_input_destroy(struct wl_listener *listener,
+		void *data) {
+	struct sway_input_method_relay *relay = wl_container_of(listener, relay,
+		text_input_destroy);
+	struct sway_text_input *text_input = text_input_to_sway(relay,
+		(struct wlr_text_input_v3*)data);
+
+	if (text_input->input->current_enabled) {
+		relay_disable_text_input(relay, text_input);
+	}
+	text_input_clear_pending_focused_surface(text_input);
+	wl_list_remove(&text_input->link);
+	text_input->input = NULL;
+	free(text_input);
+}
+
+static void handle_pending_focused_surface_destroy(struct wl_listener *listener,
+		void *data) {
+	struct sway_text_input *text_input = wl_container_of(listener, text_input,
+		pending_focused_surface_destroy);
+	struct wlr_surface *surface = data;
+	assert(text_input->pending_focused_surface == surface);
+	text_input->pending_focused_surface = NULL;
+}
+
+struct sway_text_input *sway_text_input_create(
+		struct sway_input_method_relay *relay,
+		struct wlr_text_input_v3 *text_input) {
+	struct sway_text_input *input = calloc(1, sizeof(struct sway_text_input));
+	if (!input) {
+		return NULL;
+	}
+	input->input = text_input;
+	input->relay = relay;
+
+	relay->text_input_enable.notify = handle_text_input_enable;
+	wl_signal_add(&text_input->events.enable, &relay->text_input_enable);
+
+	relay->text_input_commit.notify = handle_text_input_commit;
+	wl_signal_add(&text_input->events.commit, &relay->text_input_commit);
+
+	relay->text_input_disable.notify = handle_text_input_disable;
+	wl_signal_add(&text_input->events.disable, &relay->text_input_disable);
+
+	relay->text_input_destroy.notify = handle_text_input_destroy;
+	wl_signal_add(&text_input->events.destroy, &relay->text_input_destroy);
+
+	input->pending_focused_surface_destroy.notify =
+		handle_pending_focused_surface_destroy;
+	wl_list_init(&input->pending_focused_surface_destroy.link);
+	return input;
+}
+
+static void relay_handle_text_input(struct wl_listener *listener,
+		void *data) {
+	struct sway_input_method_relay *relay = wl_container_of(listener, relay,
+		text_input_new);
+	struct wlr_text_input_v3 *wlr_text_input = data;
+	if (relay->seat->wlr_seat != wlr_text_input->seat) {
+		return;
+	}
+
+	struct sway_text_input *text_input = sway_text_input_create(relay,
+		wlr_text_input);
+	if (!text_input) {
+		return;
+	}
+	wl_list_insert(&relay->text_inputs, &text_input->link);
+}
+
+static void relay_handle_input_method(struct wl_listener *listener,
+		void *data) {
+	struct sway_input_method_relay *relay = wl_container_of(listener, relay,
+		input_method_new);
+	struct wlr_input_method_v2 *input_method = data;
+	if (relay->seat->wlr_seat != input_method->seat) {
+		return;
+	}
+
+	if (relay->input_method != NULL) {
+		sway_log(SWAY_INFO, "Attempted to connect second input method to a seat");
+		wlr_input_method_v2_send_unavailable(input_method);
+		return;
+	}
+
+	relay->input_method = input_method;
+	wl_signal_add(&relay->input_method->events.commit,
+		&relay->input_method_commit);
+	relay->input_method_commit.notify = handle_im_commit;
+	wl_signal_add(&relay->input_method->events.destroy,
+		&relay->input_method_destroy);
+	relay->input_method_destroy.notify = handle_im_destroy;
+
+	struct sway_text_input *text_input = relay_get_focusable_text_input(relay);
+	if (text_input) {
+		wlr_text_input_v3_send_enter(text_input->input,
+			text_input->pending_focused_surface);
+		text_input_clear_pending_focused_surface(text_input);
+	}
+}
+
+void sway_input_method_relay_init(struct sway_seat *seat,
+		struct sway_input_method_relay *relay) {
+	relay->seat = seat;
+	wl_list_init(&relay->text_inputs);
+
+	relay->text_input_new.notify = relay_handle_text_input;
+	wl_signal_add(&server.text_input->events.text_input,
+		&relay->text_input_new);
+
+	relay->input_method_new.notify = relay_handle_input_method;
+	wl_signal_add(
+		&server.input_method->events.input_method,
+		&relay->input_method_new);
+}
+
+void sway_input_method_relay_set_focus(struct sway_input_method_relay *relay,
+		struct wlr_surface *surface) {
+	struct sway_text_input *text_input;
+	wl_list_for_each(text_input, &relay->text_inputs, link) {
+		if (text_input->pending_focused_surface) {
+			assert(text_input->input->focused_surface == NULL);
+			if (surface != text_input->pending_focused_surface) {
+				text_input_clear_pending_focused_surface(text_input);
+			}
+		} else if (text_input->input->focused_surface) {
+			assert(text_input->pending_focused_surface == NULL);
+			if (surface != text_input->input->focused_surface) {
+				relay_disable_text_input(relay, text_input);
+				wlr_text_input_v3_send_leave(text_input->input);
+			}
+		}
+
+		if (surface
+				&& wl_resource_get_client(text_input->input->resource)
+				== wl_resource_get_client(surface->resource)) {
+			if (relay->input_method) {
+				wlr_text_input_v3_send_enter(text_input->input, surface);
+			} else {
+				text_input_set_pending_focused_surface(text_input, surface);
+			}
+		}
+	}
+}

sway/meson.build

@@ -33,6 +33,7 @@ sway_sources = files(
 	'input/seatop_resize_tiling.c',
 	'input/switch.c',
 	'input/tablet.c',
+	'input/text_input.c',
 
 	'config/bar.c',
 	'config/output.c',

sway/server.c

@@ -138,6 +138,8 @@ bool server_init(struct sway_server *server) {
 		handle_output_power_manager_set_mode;
 	wl_signal_add(&server->output_power_manager_v1->events.set_mode,
 		&server->output_power_manager_set_mode);
+	server->input_method = wlr_input_method_manager_v2_create(server->wl_display);
+	server->text_input = wlr_text_input_manager_v3_create(server->wl_display);
 
 	wlr_export_dmabuf_manager_v1_create(server->wl_display);
 	wlr_screencopy_manager_v1_create(server->wl_display);