#define _POSIX_C_SOURCE 200809L
#include <assert.h>
#include <stdbool.h>
#include <stdlib.h>
#include <string.h>
#include <wayland-server-core.h>
#include <wlr/backend.h>
#include <wlr/backend/headless.h>
#include <wlr/backend/multi.h>
#include <wlr/config.h>
#include <wlr/render/wlr_renderer.h>
#include <wlr/types/wlr_compositor.h>
#include <wlr/types/wlr_content_type_v1.h>
#include <wlr/types/wlr_cursor_shape_v1.h>
#include <wlr/types/wlr_data_control_v1.h>
#include <wlr/types/wlr_drm.h>
#include <wlr/types/wlr_export_dmabuf_v1.h>
#include <wlr/types/wlr_fractional_scale_v1.h>
#include <wlr/types/wlr_gamma_control_v1.h>
#include <wlr/types/wlr_idle.h>
#include <wlr/types/wlr_idle_notify_v1.h>
#include <wlr/types/wlr_layer_shell_v1.h>
#include <wlr/types/wlr_linux_dmabuf_v1.h>
#include <wlr/types/wlr_pointer_constraints_v1.h>
#include <wlr/types/wlr_primary_selection_v1.h>
#include <wlr/types/wlr_relative_pointer_v1.h>
#include <wlr/types/wlr_screencopy_v1.h>
#include <wlr/types/wlr_single_pixel_buffer_v1.h>
#include <wlr/types/wlr_server_decoration.h>
#include <wlr/types/wlr_subcompositor.h>
#include <wlr/types/wlr_tablet_v2.h>
#include <wlr/types/wlr_viewporter.h>
#include <wlr/types/wlr_xcursor_manager.h>
#include <wlr/types/wlr_xdg_activation_v1.h>
#include <wlr/types/wlr_xdg_decoration_v1.h>
#include <wlr/types/wlr_xdg_foreign_registry.h>
#include <wlr/types/wlr_xdg_foreign_v1.h>
#include <wlr/types/wlr_xdg_foreign_v2.h>
#include <wlr/types/wlr_xdg_output_v1.h>
#include "config.h"
#include "list.h"
#include "log.h"
#include "sway/config.h"
#include "sway/desktop/idle_inhibit_v1.h"
#include "sway/input/input-manager.h"
#include "sway/output.h"
#include "sway/server.h"
#include "sway/input/cursor.h"
#include "sway/tree/root.h"

#if HAVE_XWAYLAND
#include <wlr/xwayland/shell.h>
#include "sway/xwayland.h"
#endif

#if WLR_HAS_DRM_BACKEND
#include <wlr/types/wlr_drm_lease_v1.h>
#endif

#define SWAY_XDG_SHELL_VERSION 2
#define SWAY_LAYER_SHELL_VERSION 4

#if WLR_HAS_DRM_BACKEND
static void handle_drm_lease_request(struct wl_listener *listener, void *data) {
	/* We only offer non-desktop outputs, but in the future we might want to do
	 * more logic here. */

	struct wlr_drm_lease_request_v1 *req = data;
	struct wlr_drm_lease_v1 *lease = wlr_drm_lease_request_v1_grant(req);
	if (!lease) {
		sway_log(SWAY_ERROR, "Failed to grant lease request");
		wlr_drm_lease_request_v1_reject(req);
	}
}
#endif

static bool filter_global(const struct wl_client *client,
		const struct wl_global *global, void *data) {
#if HAVE_XWAYLAND
	struct wlr_xwayland *xwayland = server.xwayland.wlr_xwayland;
	if (global == xwayland->shell_v1->global) {
		return xwayland->server != NULL && client == xwayland->server->client;
	}
#endif

	return true;
}

bool server_init(struct sway_server *server) {
	sway_log(SWAY_DEBUG, "Initializing Wayland server");
	server->wl_display = wl_display_create();
	server->wl_event_loop = wl_display_get_event_loop(server->wl_display);

	wl_display_set_global_filter(server->wl_display, filter_global, NULL);

	server->backend = wlr_backend_autocreate(server->wl_display, &server->session);
	if (!server->backend) {
		sway_log(SWAY_ERROR, "Unable to create backend");
		return false;
	}

	server->renderer = wlr_renderer_autocreate(server->backend);
	if (!server->renderer) {
		sway_log(SWAY_ERROR, "Failed to create renderer");
		return false;
	}

	wlr_renderer_init_wl_shm(server->renderer, server->wl_display);

	if (wlr_renderer_get_dmabuf_texture_formats(server->renderer) != NULL) {
		wlr_drm_create(server->wl_display, server->renderer);
		server->linux_dmabuf_v1 = wlr_linux_dmabuf_v1_create_with_renderer(
			server->wl_display, 4, server->renderer);
	}

	server->allocator = wlr_allocator_autocreate(server->backend,
		server->renderer);
	if (!server->allocator) {
		sway_log(SWAY_ERROR, "Failed to create allocator");
		return false;
	}

	server->compositor = wlr_compositor_create(server->wl_display, 6,
		server->renderer);
	server->compositor_new_surface.notify = handle_compositor_new_surface;
	wl_signal_add(&server->compositor->events.new_surface,
		&server->compositor_new_surface);

	wlr_subcompositor_create(server->wl_display);

	server->data_device_manager =
		wlr_data_device_manager_create(server->wl_display);

	server->gamma_control_manager_v1 =
		wlr_gamma_control_manager_v1_create(server->wl_display);
	server->gamma_control_set_gamma.notify = handle_gamma_control_set_gamma;
	wl_signal_add(&server->gamma_control_manager_v1->events.set_gamma,
		&server->gamma_control_set_gamma);

	server->new_output.notify = handle_new_output;
	wl_signal_add(&server->backend->events.new_output, &server->new_output);
	server->output_layout_change.notify = handle_output_layout_change;
	wl_signal_add(&root->output_layout->events.change,
		&server->output_layout_change);

	wlr_xdg_output_manager_v1_create(server->wl_display, root->output_layout);

	server->idle = wlr_idle_create(server->wl_display);
	server->idle_notifier_v1 = wlr_idle_notifier_v1_create(server->wl_display);
	sway_idle_inhibit_manager_v1_init();

	server->layer_shell = wlr_layer_shell_v1_create(server->wl_display,
		SWAY_LAYER_SHELL_VERSION);
	wl_signal_add(&server->layer_shell->events.new_surface,
		&server->layer_shell_surface);
	server->layer_shell_surface.notify = handle_layer_shell_surface;

	server->xdg_shell = wlr_xdg_shell_create(server->wl_display,
		SWAY_XDG_SHELL_VERSION);
	wl_signal_add(&server->xdg_shell->events.new_surface,
		&server->xdg_shell_surface);
	server->xdg_shell_surface.notify = handle_xdg_shell_surface;

	server->tablet_v2 = wlr_tablet_v2_create(server->wl_display);

	server->server_decoration_manager =
		wlr_server_decoration_manager_create(server->wl_display);
	wlr_server_decoration_manager_set_default_mode(
		server->server_decoration_manager,
		WLR_SERVER_DECORATION_MANAGER_MODE_SERVER);
	wl_signal_add(&server->server_decoration_manager->events.new_decoration,
		&server->server_decoration);
	server->server_decoration.notify = handle_server_decoration;
	wl_list_init(&server->decorations);

	server->xdg_decoration_manager =
		wlr_xdg_decoration_manager_v1_create(server->wl_display);
	wl_signal_add(
			&server->xdg_decoration_manager->events.new_toplevel_decoration,
			&server->xdg_decoration);
	server->xdg_decoration.notify = handle_xdg_decoration;
	wl_list_init(&server->xdg_decorations);

	server->relative_pointer_manager =
		wlr_relative_pointer_manager_v1_create(server->wl_display);

	server->pointer_constraints =
		wlr_pointer_constraints_v1_create(server->wl_display);
	server->pointer_constraint.notify = handle_pointer_constraint;
	wl_signal_add(&server->pointer_constraints->events.new_constraint,
		&server->pointer_constraint);

	server->presentation =
		wlr_presentation_create(server->wl_display, server->backend);

	server->output_manager_v1 =
		wlr_output_manager_v1_create(server->wl_display);
	server->output_manager_apply.notify = handle_output_manager_apply;
	wl_signal_add(&server->output_manager_v1->events.apply,
		&server->output_manager_apply);
	server->output_manager_test.notify = handle_output_manager_test;
	wl_signal_add(&server->output_manager_v1->events.test,
		&server->output_manager_test);

	server->output_power_manager_v1 =
		wlr_output_power_manager_v1_create(server->wl_display);
	server->output_power_manager_set_mode.notify =
		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);
	server->foreign_toplevel_manager =
		wlr_foreign_toplevel_manager_v1_create(server->wl_display);

	sway_session_lock_init();

#if WLR_HAS_DRM_BACKEND
	server->drm_lease_manager=
		wlr_drm_lease_v1_manager_create(server->wl_display, server->backend);
	if (server->drm_lease_manager) {
		server->drm_lease_request.notify = handle_drm_lease_request;
		wl_signal_add(&server->drm_lease_manager->events.request,
				&server->drm_lease_request);
	} else {
		sway_log(SWAY_DEBUG, "Failed to create wlr_drm_lease_device_v1");
		sway_log(SWAY_INFO, "VR will not be available");
	}
#endif

	wlr_export_dmabuf_manager_v1_create(server->wl_display);
	wlr_screencopy_manager_v1_create(server->wl_display);
	wlr_data_control_manager_v1_create(server->wl_display);
	wlr_viewporter_create(server->wl_display);
	wlr_single_pixel_buffer_manager_v1_create(server->wl_display);
	server->content_type_manager_v1 =
		wlr_content_type_manager_v1_create(server->wl_display, 1);
	wlr_fractional_scale_manager_v1_create(server->wl_display, 1);

	struct wlr_xdg_foreign_registry *foreign_registry =
		wlr_xdg_foreign_registry_create(server->wl_display);
	wlr_xdg_foreign_v1_create(server->wl_display, foreign_registry);
	wlr_xdg_foreign_v2_create(server->wl_display, foreign_registry);

	server->xdg_activation_v1 = wlr_xdg_activation_v1_create(server->wl_display);
	server->xdg_activation_v1_request_activate.notify =
		xdg_activation_v1_handle_request_activate;
	wl_signal_add(&server->xdg_activation_v1->events.request_activate,
		&server->xdg_activation_v1_request_activate);
	server->xdg_activation_v1_new_token.notify =
		xdg_activation_v1_handle_new_token;
	wl_signal_add(&server->xdg_activation_v1->events.new_token,
		&server->xdg_activation_v1_new_token);

	struct wlr_cursor_shape_manager_v1 *cursor_shape_manager =
		wlr_cursor_shape_manager_v1_create(server->wl_display, 1);
	server->request_set_cursor_shape.notify = handle_request_set_cursor_shape;
	wl_signal_add(&cursor_shape_manager->events.request_set_shape, &server->request_set_cursor_shape);

	wl_list_init(&server->pending_launcher_ctxs);

	// Avoid using "wayland-0" as display socket
	char name_candidate[16];
	for (unsigned int i = 1; i <= 32; ++i) {
		snprintf(name_candidate, sizeof(name_candidate), "wayland-%u", i);
		if (wl_display_add_socket(server->wl_display, name_candidate) >= 0) {
			server->socket = strdup(name_candidate);
			break;
		}
	}

	if (!server->socket) {
		sway_log(SWAY_ERROR, "Unable to open wayland socket");
		wlr_backend_destroy(server->backend);
		return false;
	}

	server->headless_backend = wlr_headless_backend_create(server->wl_display);
	if (!server->headless_backend) {
		sway_log(SWAY_ERROR, "Failed to create secondary headless backend");
		wlr_backend_destroy(server->backend);
		return false;
	} else {
		wlr_multi_backend_add(server->backend, server->headless_backend);
	}

	struct wlr_output *wlr_output =
			wlr_headless_add_output(server->headless_backend, 800, 600);
	wlr_output_set_name(wlr_output, "FALLBACK");
	root->fallback_output = output_create(wlr_output);

	// This may have been set already via -Dtxn-timeout
	if (!server->txn_timeout_ms) {
		server->txn_timeout_ms = 200;
	}

	server->dirty_nodes = create_list();

	server->input = input_manager_create(server);
	input_manager_get_default_seat(); // create seat0

	return true;
}

void server_fini(struct sway_server *server) {
	// TODO: free sway-specific resources
#if HAVE_XWAYLAND
	wlr_xwayland_destroy(server->xwayland.wlr_xwayland);
#endif
	wl_display_destroy_clients(server->wl_display);
	wl_display_destroy(server->wl_display);
	list_free(server->dirty_nodes);
}

bool server_start(struct sway_server *server) {
#if HAVE_XWAYLAND
	if (config->xwayland != XWAYLAND_MODE_DISABLED) {
		sway_log(SWAY_DEBUG, "Initializing Xwayland (lazy=%d)",
				config->xwayland == XWAYLAND_MODE_LAZY);
		server->xwayland.wlr_xwayland =
			wlr_xwayland_create(server->wl_display, server->compositor,
					config->xwayland == XWAYLAND_MODE_LAZY);
		if (!server->xwayland.wlr_xwayland) {
			sway_log(SWAY_ERROR, "Failed to start Xwayland");
			unsetenv("DISPLAY");
		} else {
			wl_signal_add(&server->xwayland.wlr_xwayland->events.new_surface,
				&server->xwayland_surface);
			server->xwayland_surface.notify = handle_xwayland_surface;
			wl_signal_add(&server->xwayland.wlr_xwayland->events.ready,
				&server->xwayland_ready);
			server->xwayland_ready.notify = handle_xwayland_ready;

			setenv("DISPLAY", server->xwayland.wlr_xwayland->display_name, true);

			/* xcursor configured by the default seat */
		}
	}
#endif

	if (config->primary_selection) {
		wlr_primary_selection_v1_device_manager_create(server->wl_display);
	}

	sway_log(SWAY_INFO, "Starting backend on wayland display '%s'",
			server->socket);
	if (!wlr_backend_start(server->backend)) {
		sway_log(SWAY_ERROR, "Failed to start backend");
		wlr_backend_destroy(server->backend);
		return false;
	}

	return true;
}

void server_run(struct sway_server *server) {
	sway_log(SWAY_INFO, "Running compositor on wayland display '%s'",
			server->socket);
	wl_display_run(server->wl_display);
}