1 files changed, 347 insertions, 0 deletions

diff --git a/sway/desktop/layer_shell.c b/sway/desktop/layer_shell.c
new file mode 100644
index 00000000..f841e5f1
--- /dev/null
+++ b/sway/desktop/layer_shell.c
@@ -0,0 +1,347 @@
+#include <stdbool.h>
+#include <stdlib.h>
+#include <string.h>
+#include <wayland-server.h>
+#include <wlr/types/wlr_box.h>
+#include <wlr/types/wlr_layer_shell.h>
+#include <wlr/types/wlr_output_damage.h>
+#include <wlr/types/wlr_output.h>
+#include <wlr/util/log.h>
+#include "sway/input/input-manager.h"
+#include "sway/input/seat.h"
+#include "sway/layers.h"
+#include "sway/output.h"
+#include "sway/server.h"
+#include "sway/tree/layout.h"
+
+static void apply_exclusive(struct wlr_box *usable_area,
+		uint32_t anchor, int32_t exclusive,
+		int32_t margin_top, int32_t margin_right,
+		int32_t margin_bottom, int32_t margin_left) {
+	if (exclusive <= 0) {
+		return;
+	}
+	struct {
+		uint32_t anchors;
+		int *positive_axis;
+		int *negative_axis;
+		int margin;
+	} edges[] = {
+		{
+			.anchors =
+				ZWLR_LAYER_SURFACE_V1_ANCHOR_LEFT |
+				ZWLR_LAYER_SURFACE_V1_ANCHOR_RIGHT |
+				ZWLR_LAYER_SURFACE_V1_ANCHOR_TOP,
+			.positive_axis = &usable_area->y,
+			.negative_axis = &usable_area->height,
+			.margin = margin_top,
+		},
+		{
+			.anchors =
+				ZWLR_LAYER_SURFACE_V1_ANCHOR_LEFT |
+				ZWLR_LAYER_SURFACE_V1_ANCHOR_RIGHT |
+				ZWLR_LAYER_SURFACE_V1_ANCHOR_BOTTOM,
+			.positive_axis = NULL,
+			.negative_axis = &usable_area->height,
+			.margin = margin_bottom,
+		},
+		{
+			.anchors =
+				ZWLR_LAYER_SURFACE_V1_ANCHOR_LEFT |
+				ZWLR_LAYER_SURFACE_V1_ANCHOR_TOP |
+				ZWLR_LAYER_SURFACE_V1_ANCHOR_BOTTOM,
+			.positive_axis = &usable_area->x,
+			.negative_axis = &usable_area->width,
+			.margin = margin_left,
+		},
+		{
+			.anchors =
+				ZWLR_LAYER_SURFACE_V1_ANCHOR_RIGHT |
+				ZWLR_LAYER_SURFACE_V1_ANCHOR_TOP |
+				ZWLR_LAYER_SURFACE_V1_ANCHOR_BOTTOM,
+			.positive_axis = NULL,
+			.negative_axis = &usable_area->width,
+			.margin = margin_right,
+		},
+	};
+	for (size_t i = 0; i < sizeof(edges) / sizeof(edges[0]); ++i) {
+		if ((anchor & edges[i].anchors) == edges[i].anchors) {
+			if (edges[i].positive_axis) {
+				*edges[i].positive_axis += exclusive + edges[i].margin;
+			}
+			if (edges[i].negative_axis) {
+				*edges[i].negative_axis -= exclusive + edges[i].margin;
+			}
+		}
+	}
+}
+
+static void arrange_layer(struct sway_output *output, struct wl_list *list,
+		struct wlr_box *usable_area, bool exclusive) {
+	struct sway_layer_surface *sway_layer;
+	struct wlr_box full_area = { 0 };
+	wlr_output_effective_resolution(output->wlr_output,
+			&full_area.width, &full_area.height);
+	wl_list_for_each(sway_layer, list, link) {
+		struct wlr_layer_surface *layer = sway_layer->layer_surface;
+		struct wlr_layer_surface_state *state = &layer->current;
+		if (exclusive != (state->exclusive_zone > 0)) {
+			continue;
+		}
+		struct wlr_box bounds;
+		if (state->exclusive_zone == -1) {
+			bounds = full_area;
+		} else {
+			bounds = *usable_area;
+		}
+		struct wlr_box box = {
+			.width = state->desired_width,
+			.height = state->desired_height
+		};
+		// Horizontal axis
+		const uint32_t both_horiz = ZWLR_LAYER_SURFACE_V1_ANCHOR_LEFT
+			| ZWLR_LAYER_SURFACE_V1_ANCHOR_RIGHT;
+		if ((state->anchor & both_horiz) && box.width == 0) {
+			box.x = bounds.x;
+			box.width = bounds.width;
+		} else if ((state->anchor & ZWLR_LAYER_SURFACE_V1_ANCHOR_LEFT)) {
+			box.x = bounds.x;
+		} else if ((state->anchor & ZWLR_LAYER_SURFACE_V1_ANCHOR_RIGHT)) {
+			box.x = bounds.x + (bounds.width - box.width);
+		} else {
+			box.x = bounds.x + ((bounds.width / 2) - (box.width / 2));
+		}
+		// Vertical axis
+		const uint32_t both_vert = ZWLR_LAYER_SURFACE_V1_ANCHOR_TOP
+			| ZWLR_LAYER_SURFACE_V1_ANCHOR_BOTTOM;
+		if ((state->anchor & both_vert) && box.height == 0) {
+			box.y = bounds.y;
+			box.height = bounds.height;
+		} else if ((state->anchor & ZWLR_LAYER_SURFACE_V1_ANCHOR_TOP)) {
+			box.y = bounds.y;
+		} else if ((state->anchor & ZWLR_LAYER_SURFACE_V1_ANCHOR_BOTTOM)) {
+			box.y = bounds.y + (bounds.height - box.height);
+		} else {
+			box.y = bounds.y + ((bounds.height / 2) - (box.height / 2));
+		}
+		// Margin
+		if ((state->anchor & both_horiz) == both_horiz) {
+			box.x += state->margin.left;
+			box.width -= state->margin.left + state->margin.right;
+		} else if ((state->anchor & ZWLR_LAYER_SURFACE_V1_ANCHOR_LEFT)) {
+			box.x += state->margin.left;
+		} else if ((state->anchor & ZWLR_LAYER_SURFACE_V1_ANCHOR_RIGHT)) {
+			box.x -= state->margin.right;
+		}
+		if ((state->anchor & both_vert) == both_vert) {
+			box.y += state->margin.top;
+			box.height -= state->margin.top + state->margin.bottom;
+		} else if ((state->anchor & ZWLR_LAYER_SURFACE_V1_ANCHOR_TOP)) {
+			box.y += state->margin.top;
+		} else if ((state->anchor & ZWLR_LAYER_SURFACE_V1_ANCHOR_BOTTOM)) {
+			box.y -= state->margin.bottom;
+		}
+		if (box.width < 0 || box.height < 0) {
+			// TODO: Bubble up a protocol error?
+			wlr_layer_surface_close(layer);
+			continue;
+		}
+		// Apply
+		sway_layer->geo = box;
+		apply_exclusive(usable_area, state->anchor, state->exclusive_zone,
+				state->margin.top, state->margin.right,
+				state->margin.bottom, state->margin.left);
+		wlr_layer_surface_configure(layer, box.width, box.height);
+	}
+}
+
+void arrange_layers(struct sway_output *output) {
+	struct wlr_box usable_area = { 0 };
+	wlr_output_effective_resolution(output->wlr_output,
+			&usable_area.width, &usable_area.height);
+
+	// Arrange exclusive surfaces from top->bottom
+	arrange_layer(output, &output->layers[ZWLR_LAYER_SHELL_V1_LAYER_OVERLAY],
+			&usable_area, true);
+	arrange_layer(output, &output->layers[ZWLR_LAYER_SHELL_V1_LAYER_TOP],
+			&usable_area, true);
+	arrange_layer(output, &output->layers[ZWLR_LAYER_SHELL_V1_LAYER_BOTTOM],
+			&usable_area, true);
+	arrange_layer(output, &output->layers[ZWLR_LAYER_SHELL_V1_LAYER_BACKGROUND],
+			&usable_area, true);
+
+	if (memcmp(&usable_area, &output->usable_area,
+				sizeof(struct wlr_box)) != 0) {
+		wlr_log(L_DEBUG, "Usable area changed, rearranging output");
+		memcpy(&output->usable_area, &usable_area, sizeof(struct wlr_box));
+		arrange_windows(output->swayc, -1, -1);
+	}
+
+	// Arrange non-exlusive surfaces from top->bottom
+	usable_area.x = usable_area.y = 0;
+	wlr_output_effective_resolution(output->wlr_output,
+			&usable_area.width, &usable_area.height);
+	arrange_layer(output, &output->layers[ZWLR_LAYER_SHELL_V1_LAYER_OVERLAY],
+			&usable_area, false);
+	arrange_layer(output, &output->layers[ZWLR_LAYER_SHELL_V1_LAYER_TOP],
+			&usable_area, false);
+	arrange_layer(output, &output->layers[ZWLR_LAYER_SHELL_V1_LAYER_BOTTOM],
+			&usable_area, false);
+	arrange_layer(output, &output->layers[ZWLR_LAYER_SHELL_V1_LAYER_BACKGROUND],
+			&usable_area, false);
+
+	// Find topmost keyboard interactive layer, if such a layer exists
+	uint32_t layers_above_shell[] = {
+		ZWLR_LAYER_SHELL_V1_LAYER_OVERLAY,
+		ZWLR_LAYER_SHELL_V1_LAYER_TOP,
+	};
+	size_t nlayers = sizeof(layers_above_shell) / sizeof(layers_above_shell[0]);
+	struct sway_layer_surface *layer, *topmost = NULL;
+	for (size_t i = 0; i < nlayers; ++i) {
+		wl_list_for_each_reverse(layer,
+				&output->layers[layers_above_shell[i]], link) {
+			if (layer->layer_surface->current.keyboard_interactive) {
+				topmost = layer;
+				break;
+			}
+		}
+		if (topmost != NULL) {
+			break;
+		}
+	}
+
+	struct sway_seat *seat;
+	wl_list_for_each(seat, &input_manager->seats, link) {
+		seat_set_focus_layer(seat, topmost ? topmost->layer_surface : NULL);
+	}
+}
+
+static void handle_output_destroy(struct wl_listener *listener, void *data) {
+	struct sway_layer_surface *sway_layer =
+		wl_container_of(listener, sway_layer, output_destroy);
+	wl_list_remove(&sway_layer->output_destroy.link);
+	sway_layer->layer_surface->output = NULL;
+	wlr_layer_surface_close(sway_layer->layer_surface);
+}
+
+static void handle_surface_commit(struct wl_listener *listener, void *data) {
+	struct sway_layer_surface *layer =
+		wl_container_of(listener, layer, surface_commit);
+	struct wlr_layer_surface *layer_surface = layer->layer_surface;
+	struct wlr_output *wlr_output = layer_surface->output;
+	if (wlr_output == NULL) {
+		return;
+	}
+
+	struct sway_output *output = wlr_output->data;
+	struct wlr_box old_geo = layer->geo;
+	arrange_layers(output);
+	if (memcmp(&old_geo, &layer->geo, sizeof(struct wlr_box)) != 0) {
+		output_damage_surface(output, old_geo.x, old_geo.y,
+			layer_surface->surface, true);
+		output_damage_surface(output, layer->geo.x, layer->geo.y,
+			layer_surface->surface, true);
+	} else {
+		output_damage_surface(output, layer->geo.x, layer->geo.y,
+			layer_surface->surface, false);
+	}
+}
+
+static void unmap(struct sway_layer_surface *sway_layer) {
+	struct wlr_output *wlr_output = sway_layer->layer_surface->output;
+	if (wlr_output == NULL) {
+		return;
+	}
+	struct sway_output *output = wlr_output->data;
+	output_damage_surface(output, sway_layer->geo.x, sway_layer->geo.y,
+		sway_layer->layer_surface->surface, true);
+}
+
+static void handle_destroy(struct wl_listener *listener, void *data) {
+	struct sway_layer_surface *sway_layer =
+		wl_container_of(listener, sway_layer, destroy);
+	wlr_log(L_DEBUG, "Layer surface destroyed (%s)",
+		sway_layer->layer_surface->namespace);
+	if (sway_layer->layer_surface->mapped) {
+		unmap(sway_layer);
+	}
+	wl_list_remove(&sway_layer->link);
+	wl_list_remove(&sway_layer->destroy.link);
+	wl_list_remove(&sway_layer->map.link);
+	wl_list_remove(&sway_layer->unmap.link);
+	wl_list_remove(&sway_layer->surface_commit.link);
+	if (sway_layer->layer_surface->output != NULL) {
+		struct sway_output *output = sway_layer->layer_surface->output->data;
+		arrange_layers(output);
+
+		wl_list_remove(&sway_layer->output_destroy.link);
+	}
+	free(sway_layer);
+}
+
+static void handle_map(struct wl_listener *listener, void *data) {
+	struct sway_layer_surface *sway_layer = wl_container_of(listener,
+			sway_layer, map);
+	struct sway_output *output = sway_layer->layer_surface->output->data;
+	output_damage_surface(output, sway_layer->geo.x, sway_layer->geo.y,
+		sway_layer->layer_surface->surface, true);
+	// TODO: send enter to subsurfaces and popups
+	wlr_surface_send_enter(sway_layer->layer_surface->surface,
+		sway_layer->layer_surface->output);
+}
+
+static void handle_unmap(struct wl_listener *listener, void *data) {
+	struct sway_layer_surface *sway_layer = wl_container_of(
+			listener, sway_layer, unmap);
+	unmap(sway_layer);
+}
+
+void handle_layer_shell_surface(struct wl_listener *listener, void *data) {
+	struct wlr_layer_surface *layer_surface = data;
+	struct sway_server *server =
+		wl_container_of(listener, server, layer_shell_surface);
+	wlr_log(L_DEBUG, "new layer surface: namespace %s layer %d anchor %d "
+			"size %dx%d margin %d,%d,%d,%d",
+		layer_surface->namespace, layer_surface->layer, layer_surface->layer,
+		layer_surface->client_pending.desired_width,
+		layer_surface->client_pending.desired_height,
+		layer_surface->client_pending.margin.top,
+		layer_surface->client_pending.margin.right,
+		layer_surface->client_pending.margin.bottom,
+		layer_surface->client_pending.margin.left);
+
+	struct sway_layer_surface *sway_layer =
+		calloc(1, sizeof(struct sway_layer_surface));
+	if (!sway_layer) {
+		return;
+	}
+
+	sway_layer->surface_commit.notify = handle_surface_commit;
+	wl_signal_add(&layer_surface->surface->events.commit,
+		&sway_layer->surface_commit);
+
+	sway_layer->output_destroy.notify = handle_output_destroy;
+	wl_signal_add(&layer_surface->output->events.destroy,
+		&sway_layer->output_destroy);
+
+	sway_layer->destroy.notify = handle_destroy;
+	wl_signal_add(&layer_surface->events.destroy, &sway_layer->destroy);
+	sway_layer->map.notify = handle_map;
+	wl_signal_add(&layer_surface->events.map, &sway_layer->map);
+	sway_layer->unmap.notify = handle_unmap;
+	wl_signal_add(&layer_surface->events.unmap, &sway_layer->unmap);
+	// TODO: Listen for subsurfaces
+
+	sway_layer->layer_surface = layer_surface;
+	layer_surface->data = sway_layer;
+
+	struct sway_output *output = layer_surface->output->data;
+	wl_list_insert(&output->layers[layer_surface->layer], &sway_layer->link);
+
+	// Temporarily set the layer's current state to client_pending
+	// So that we can easily arrange it
+	struct wlr_layer_surface_state old_state = layer_surface->current;
+	layer_surface->current = layer_surface->client_pending;
+	arrange_layers(output);
+	layer_surface->current = old_state;
+}