#undef NDEBUG
#include <cassert>
#include <core/variant.h>
#include <core/os/time.h>
#include <scene/gui/option_button.h>
#include <scene/main/viewport.h>
#include <scene/3d/camera.h>
#include <modules/voxel/terrain/voxel_lod_terrain.h>
#include <modules/imgmapper/voxel_generator_imgmapper.h>
#include "from_string.h"
#include "editor_event.h"
#include "world_editor.h"
#include "buildings_data.h"
#include "buildings_editor.h"

class HandleChangeBuildingType : public Object {
	GDCLASS(HandleChangeBuildingType, Object)
	BuildingsEditor *editor;

	void change_building_type(int index)
	{
		OptionButton *building_type =
			editor->get_as_node<OptionButton>("%building_type");
		const String &item = building_type->get_item_text(index);
		int bmode = editor->get_buildings_editor_mode();
		if (bmode == 0 || bmode == 1 ||
		    bmode == 2) /* select, move, rotate */
			editor->change_building_type(item);
		/* do not change building types in create mode (3) */
	}

public:
	HandleChangeBuildingType(BuildingsEditor *editor)
		: Object()
		, editor(editor)
	{
		OptionButton *building_type =
			editor->get_as_node<OptionButton>("%building_type");
		building_type->connect("item_selected", this,
				       "change_building_type");
	}
	virtual ~HandleChangeBuildingType()
	{
		OptionButton *building_type =
			editor->get_as_node<OptionButton>("%building_type");
		if (building_type->is_connected("item_selected", this,
						"change_building_type"))
			building_type->disconnect("item_selected", this,
						  "change_building_type");
	}

protected:
	static void _bind_methods()
	{
		ClassDB::bind_method(
			D_METHOD("change_building_type", "index"),
			&HandleChangeBuildingType::change_building_type);
	}
};
class HandleButton : public Object {
	GDCLASS(HandleButton, Object)
	BuildingsEditor *editor;
	String button_path;
	String event_string;
	Array event_args;
	Button *get_button()
	{
		Button *button = editor->get_as_node<Button>(button_path);
		assert(button);
		return button;
	}
	void button_handler()
	{
		editor->emit("button:" + event_string, event_args);
	}

public:
	HandleButton(BuildingsEditor *editor, const String &button_path,
		     const String &event_string,
		     const Array &event_args = Array())
		: Object()
		, editor(editor)
		, button_path(button_path)
		, event_string(event_string)
		, event_args(event_args)
	{
		if (!get_button()->is_connected("pressed", this,
						"button_handler"))
			get_button()->connect("pressed", this,
					      "button_handler");
	}
	virtual ~HandleButton()
	{
		if (get_button()->is_connected("pressed", this,
					       "button_handler"))
			get_button()->disconnect("pressed", this,
						 "button_handler");
	}
	static void _bind_methods()
	{
		ClassDB::bind_method(D_METHOD("button_handler"),
				     &HandleButton::button_handler);
	}
};

class HandleDeleteButton : public Object {
	GDCLASS(HandleDeleteButton, Object)
	BuildingsEditor *editor;

public:
	HandleDeleteButton(BuildingsEditor *editor)
		: Object()
		, editor(editor)
	{
		Button *delete_button = editor->get_as_node<Button>(
			"%buildings_delete_building");
		assert(delete_button);
		/* FIXME */
		if (!delete_button->is_connected("pressed", this,
						 "delete_building_handler"))
			delete_button->connect("pressed", this,
					       "delete_building_handler");
	}
	~HandleDeleteButton()
	{
		Button *delete_button = editor->get_as_node<Button>(
			"%buildings_delete_building");
		if (delete_button->is_connected("pressed", this,
						"delete_building_handler"))
			delete_button->disconnect("pressed", this,
						  "delete_building_handler");
	}
	void delete_building_handler()
	{
		editor->delete_building_handler();
	}
	static void _bind_methods()
	{
		ClassDB::bind_method(
			D_METHOD("delete_building_handler"),
			&HandleDeleteButton::delete_building_handler);
	}
};
static std::vector<Object *> ui_handlers;

BuildingsEditor::BuildingsEditor(WorldEditor *editor)
	: editor(editor)
	, selected_building(-1)
	, active(false)
{
}

void BuildingsEditor::exit()
{
	if (active)
		deactivate();
}

void BuildingsEditor::activate()
{
	assert(!active);
	ConfigFile config;
	Error result = config.load("res://config/stream.conf");
	ERR_FAIL_COND_MSG(result != OK, "Failed to load config");
	print_line("BuildingsEditor ACTIVE");
	Array args;
	ui_handlers.push_back(memnew(HandleButton(
		this, "%buildings_create_building", "create_building", args)));
	ui_handlers.push_back(memnew(HandleChangeBuildingType(this)));
	ui_handlers.push_back(memnew(HandleDeleteButton(this)));
	int i;
	for (i = 0; i < (int)ui_handlers.size(); i++)
		assert(ui_handlers[i]);
	/* TODO: make separate function for this */
	EditorEvent::get_singleton()->event.add_listener(
		this, &BuildingsEditor::event_handler);
	Dictionary buildings_data =
		config.get_value("buildings", "building_data");
	OptionButton *building_type =
		get_as_node<OptionButton>("%building_type");
	building_type->clear();
	List<Variant> keys;
	buildings_data.get_key_list(&keys);
	List<Variant>::Element *e = keys.front();
	while (e) {
		const String &key = e->get();
		print_line("EE::" + key);
		building_type->add_item(key);
		e = e->next();
	}
	active = true;
}

void BuildingsEditor::deactivate()
{
	assert(active);
	EditorEvent::get_singleton()->event.remove_listener(
		this, &BuildingsEditor::event_handler);
	print_line("BuildingsEditor DEACTIVE");
	int i;
	for (i = 0; i < (int)ui_handlers.size(); i++)
		memdelete(ui_handlers[i]);
	ui_handlers.clear();
	active = false;
}

void BuildingsEditor::event_handler(const String &event, const Array &args)
{
	assert(active);
	print_line("E::" + event);
	if (event == "mouse_drag")
		mouse_drag(args[0]);
	else if (event == "mouse_press")
		mouse_press(args[0]);
	else if (event == "button:create_building")
		handle_create_building();
	else if (event == "result:get_closest_building") {
		select_building(args[0], args[3], args[4]);
		if (get_buildings_editor_mode() == 2 /* rotate */) {
			/* move rot cursor too */
			get_as_node<Spatial>("%building_rot_cursor")
				->set_global_transform(selected_building_xform);
		}
	} else if (event == "result:get_building_types") {
		/* TODO: replace with direct data access */
	}
	print_line("buildings::" + event);
}

void BuildingsEditor::handle_create_building()
{
	print_line("create_building");
	int bmode = get_buildings_editor_mode();
	assert(bmode == 3);
	OptionButton *building_type =
		get_as_node<OptionButton>("%building_type");
	int index = building_type->get_selected();
	if (index >= 0) {
		const String &item = building_type->get_item_text(index);
		Array args;
		Transform xform = get_as_node<Spatial>("%building_cursor")
					  ->get_global_transform();
		Dictionary building_data;
		/* FIXME: calculate AABBs as in previous editor */
		String building_xform = to_string<Transform>(xform);
		building_data["id"] = item;
		building_data["key"] = String::num_uint64(
			String(item + building_xform +
			       itos(Time::get_singleton()->get_ticks_usec()))
				.hash64(),
			16);
		building_data["xform"] = building_xform;
		args.push_back(building_data);
		editor->editor_command("create_building", args);
	}
}

template <class T>
inline void BuildingsEditor::mode_visibility(int mode, const String &path)
{
	T *obj = get_as_node<T>(path);
	if (get_buildings_editor_mode() == mode) {
		if (!obj->is_visible())
			obj->show();
	} else {
		if (obj->is_visible())
			obj->hide();
	}
}

void BuildingsEditor::update(float delta)
{
#ifdef _VERBOSE_DEBUG
	if (active)
		print_line("update: " + String::num(delta) + " " +
			   itos(editor->get_current_mode()) + " " +
			   itos(editor->get_camera_mode()));
#endif
	if (!active)
		activate();
	int mode = get_buildings_editor_mode();
	if (mode == 2) {
		Spatial *rot_cursor =
			get_as_node<Spatial>("%building_rot_cursor");
		if (!rot_cursor->is_visible())
			rot_cursor->set_global_transform(
				selected_building_xform);
	}
	mode_visibility<Button>(0, "%buildings_delete_building");
	mode_visibility<Spatial>(2, "%building_rot_cursor");
	mode_visibility<Button>(3, "%buildings_create_building");
}

void BuildingsEditor::mouse_drag(const Vector2 &position)
{
	if (editor->get_current_mode() != WorldEditor::MODE_BUILDINGS) {
		print_verbose("bad editor mode: " +
			      itos(editor->get_current_mode()));
		return;
	}
	print_line("in mouse_drag");
	Camera *camera = editor->get_viewport()->get_camera();
	Vector3 start = camera->project_ray_origin(position);
	Vector3 normal = camera->project_ray_normal(position);
	Vector3 end = start + normal * camera->get_zfar();
	PhysicsDirectSpaceState *space_state =
		editor->get_world()->get_direct_space_state();
	PhysicsDirectSpaceState::RayResult result;
	Set<RID> excludes;
	bool r = space_state->intersect_ray(start, end, result, excludes,
					    1 << 15, false, true, false);
	if (r && result.rid != RID()) {
		Vector3 proj = result.position;
		int mode = get_buildings_editor_mode();
		switch (mode) {
		case 1: {
			/* move */
			print_verbose("move: " + (proj.operator String()));
			Vector3 newpos(Math::stepify(proj.x, 2.0f), proj.y,
				       Math::stepify(proj.z, 2.0f));
			Ref<VoxelGeneratorImgMapper> gen =
				get_as_node<VoxelLodTerrain>("%VoxelLodTerrain")
					->get_generator();
			float h = gen->get_height_full(newpos);
			newpos.y = h;
			Array args;
			args.push_back(selected_building);
			args.push_back(Transform(selected_building_xform.basis,
						 newpos));
			editor->editor_command("update_building_transform",
					       args);
			Spatial *cursor =
				get_as_node<Spatial>("%building_cursor");
			Transform orig_pos = cursor->get_global_transform();
			orig_pos.origin = newpos;
			cursor->set_global_transform(orig_pos);
			selected_building_xform = Transform(
				selected_building_xform.basis, newpos);
		} break;
		case 2: {
			/* rotate */
			print_verbose("rotate: " + (proj.operator String()));
			Vector3 m = proj;
			m.y = selected_building_xform.origin.y;
			Transform xform = selected_building_xform.looking_at(
				m, Vector3(0.0f, 1.0f, 0.0f));
			Array args;
			args.push_back(selected_building);
			args.push_back(xform);
			editor->editor_command("update_building_transform",
					       args);
			selected_building_xform = xform;
			get_as_node<Spatial>("%building_rot_cursor")
				->set_global_transform(xform);
		} break;
		case 3: { /* create */
			print_verbose("create: " + (proj.operator String()));
			Vector3 newpos(Math::stepify(proj.x, 2.0f), proj.y,
				       Math::stepify(proj.z, 2.0f));
			Ref<VoxelGeneratorImgMapper> gen =
				get_as_node<VoxelLodTerrain>("%VoxelLodTerrain")
					->get_generator();
			float h = gen->get_height_full(newpos);
			newpos.y = h;
			Transform xform(Basis(), newpos);
			get_as_node<Spatial>("%building_cursor")
				->set_global_transform(xform);
		} break;
		}
	}
}

void BuildingsEditor::mouse_press(const Vector2 &position)
{
	if (editor->get_current_mode() != WorldEditor::MODE_BUILDINGS) {
		print_verbose("bad editor mode: " +
			      itos(editor->get_current_mode()));
		return;
	}
	print_line("in mouse_press");
	Camera *camera = editor->get_viewport()->get_camera();
	Vector3 start = camera->project_ray_origin(position);
	Vector3 normal = camera->project_ray_normal(position);
	Vector3 end = start + normal * camera->get_zfar();
	PhysicsDirectSpaceState *space_state =
		editor->get_world()->get_direct_space_state();
	PhysicsDirectSpaceState::RayResult result;
	Set<RID> excludes;
	bool r = space_state->intersect_ray(start, end, result, excludes,
					    1 << 15, false, true, false);
	if (r && result.rid != RID()) {
		Vector3 proj = result.position;
		int mode = get_buildings_editor_mode();
		switch (mode) {
		case 0: {
			/* select */
			Array args;
			Transform xform(Basis(), proj);
			args.push_back(xform);
			editor->editor_command("get_closest_building", args);
		} break;
		case 1: {
			/* move */
			editor->editor_command("checkpoint", Array());
		} break;
		case 2: {
			/* TODO: deduplicate */
			/* rotate */
			editor->editor_command("checkpoint", Array());
			print_verbose("rotate: " + (proj.operator String()));
			Vector3 m = proj;
			m.y = selected_building_xform.origin.y;
			Transform xform = selected_building_xform.looking_at(
				m, Vector3(0.0f, 1.0f, 0.0f));
			Array args;
			args.push_back(selected_building);
			args.push_back(xform);
			editor->editor_command("update_building_transform",
					       args);
			selected_building_xform = xform;
			get_as_node<Spatial>("%building_rot_cursor")
				->set_global_transform(xform);
		} break;
		/* TODO: deduplicate */
		case 3: { /* create */
			print_verbose("create: " + (proj.operator String()));
			Vector3 newpos(Math::stepify(proj.x, 2.0f), proj.y,
				       Math::stepify(proj.z, 2.0f));
			Ref<VoxelGeneratorImgMapper> gen =
				get_as_node<VoxelLodTerrain>("%VoxelLodTerrain")
					->get_generator();
			float h = gen->get_height_full(newpos);
			newpos.y = h;
			Transform xform(Basis(), newpos);
			get_as_node<Spatial>("%building_cursor")->show();
			get_as_node<Spatial>("%building_cursor")
				->set_global_transform(xform);
		} break;
		}
	}
}

int BuildingsEditor::get_buildings_editor_mode() const
{
	const OptionButton *buildings_edit_mode =
		get_as_node<OptionButton>("%buildings_edit_mode");
	int selected = buildings_edit_mode->get_selected();
	return selected;
}

BuildingsEditor::~BuildingsEditor()
{
	if (active)
		deactivate();
}

int BuildingsEditor::get_selected_building() const
{
	return selected_building;
}

Transform BuildingsEditor::get_selected_building_xform() const
{
	return selected_building_xform;
}

void BuildingsEditor::delete_building_handler()
{
	Array args, args2;
	args.push_back(selected_building);
	editor->editor_command("remove_building", args);
	args2.push_back(selected_building_xform);
	editor->editor_command("get_closest_building", args2);
}

void BuildingsEditor::change_building_type(const String &type_name)
{
	Array args;
	int bmode = get_buildings_editor_mode();
	assert(bmode == 0 || bmode == 1 ||
	       bmode == 2); /* select, move, rotate */
	args.push_back(selected_building);
	args.push_back(type_name);
	editor->editor_command("change_building_type", args);
}

void BuildingsEditor::emit(const String &event_string, const Array &event_args)
{
	EditorEvent::get_singleton()->event.emit(event_string, event_args);
}

void BuildingsEditor::remove_buildings_by_prefix(const String &prefix)
{
	Array args;
	args.push_back(prefix);
	editor->editor_command("remove_buildings_by_prefix", args);
}

void BuildingsEditor::select_building(const Transform &xform, int id,
				      const String &mid)
{
	int i;
	selected_building_xform = xform;
	selected_building = id;
	print_line("selected id: " + itos(id));
	OptionButton *building_type = Object::cast_to<OptionButton>(
		editor->get_node(NodePath("%building_type")));
	assert(building_type);
	bool ok = false;
	for (i = 0; i < building_type->get_item_count(); i++) {
		const String &item = building_type->get_item_text(i);
		if (item == mid) {
			building_type->select(i);
			ok = true;
			break;
		}
	}
	if (ok) {
		Button *delete_button =
			get_as_node<Button>("%buildings_delete_building");
		delete_button->show();
	}
	Spatial *cursor = get_as_node<Spatial>("%building_cursor");
	/* Show cursor and change cursor position */
	if (!cursor->is_visible())
		cursor->show();
	Transform orig_xform = cursor->get_global_transform();
	orig_xform.origin = xform.origin;
	cursor->set_global_transform(orig_xform);
}

void BuildingsEditor::editor_command(const String &command, const Array &args)
{
	if (command == "select_building") {
		select_building(args[0], args[1], args[2]);
	}
}

template <class T> T *BuildingsEditor::get_as_node(const String &path)
{
	Node *node = scene()->get_node(NodePath(path));
	assert(node);
	T *ret = Object::cast_to<T>(node);
	assert(ret);
	return ret;
}

template <class T>
const T *BuildingsEditor::get_as_node(const String &path) const
{
	const Node *node = scene()->get_node(NodePath(path));
	assert(node);
	const T *ret = Object::cast_to<T>(node);
	assert(ret);
	return ret;
}

Node *BuildingsEditor::scene()
{
	return editor->get_tree()->get_current_scene();
}

const Node *BuildingsEditor::scene() const
{
	const Node *ret = editor->get_tree()->get_current_scene();
	return ret;
}