extends Node

signal color_changed(color, button)

var pen_pressure := 1.0
var control := false
var shift := false
var alt := false

var _tools = {
	"RectSelect": "res://src/Tools/SelectionTools/RectSelect.tscn",
	"EllipseSelect": "res://src/Tools/SelectionTools/EllipseSelect.tscn",
	"PolygonSelect": "res://src/Tools/SelectionTools/PolygonSelect.tscn",
	"ColorSelect": "res://src/Tools/SelectionTools/ColorSelect.tscn",
	"MagicWand": "res://src/Tools/SelectionTools/MagicWand.tscn",
	"Lasso": "res://src/Tools/SelectionTools/Lasso.tscn",
	"Move": "res://src/Tools/Move.tscn",
	"Zoom": "res://src/Tools/Zoom.tscn",
	"Pan": "res://src/Tools/Pan.tscn",
	"ColorPicker": "res://src/Tools/ColorPicker.tscn",
	"Pencil": "res://src/Tools/Pencil.tscn",
	"Eraser": "res://src/Tools/Eraser.tscn",
	"Bucket": "res://src/Tools/Bucket.tscn",
	"Shading": "res://src/Tools/Shading.tscn",
	"LineTool": "res://src/Tools/LineTool.tscn",
	"RectangleTool": "res://src/Tools/RectangleTool.tscn",
	"EllipseTool": "res://src/Tools/EllipseTool.tscn",
}
var _slots = {}
var _panels = {}
var _tool_buttons: Node
var _active_button := -1
var _last_position := Vector2.INF


class Slot:
	var name: String
	var kname: String
	var tool_node: Node = null
	var button: int
	var color: Color

	var pixel_perfect := false
	var horizontal_mirror := false
	var vertical_mirror := false

	func _init(slot_name: String) -> void:
		name = slot_name
		kname = name.replace(" ", "_").to_lower()
		load_config()

	func save_config() -> void:
		var config := {
			"pixel_perfect": pixel_perfect,
			"horizontal_mirror": horizontal_mirror,
			"vertical_mirror": vertical_mirror,
		}
		Global.config_cache.set_value(kname, "slot", config)

	func load_config() -> void:
		var config = Global.config_cache.get_value(kname, "slot", {})
		pixel_perfect = config.get("pixel_perfect", pixel_perfect)
		horizontal_mirror = config.get("horizontal_mirror", horizontal_mirror)
		vertical_mirror = config.get("vertical_mirror", vertical_mirror)


func _ready() -> void:
	_tool_buttons = Global.control.find_node("ToolButtons")
	_slots[BUTTON_LEFT] = Slot.new("Left tool")
	_slots[BUTTON_RIGHT] = Slot.new("Right tool")
	_panels[BUTTON_LEFT] = Global.control.find_node("LeftPanelContainer", true, false)
	_panels[BUTTON_RIGHT] = Global.control.find_node("RightPanelContainer", true, false)

	var tool_name: String = Global.config_cache.get_value(
		_slots[BUTTON_LEFT].kname, "tool", "Pencil"
	)
	if not tool_name in _tools:
		tool_name = "Pencil"
	set_tool(tool_name, BUTTON_LEFT)
	tool_name = Global.config_cache.get_value(_slots[BUTTON_RIGHT].kname, "tool", "Eraser")
	if not tool_name in _tools:
		tool_name = "Eraser"
	set_tool(tool_name, BUTTON_RIGHT)

	update_tool_buttons()
	update_tool_cursors()

	# Yield is necessary for the color picker nodes to update their color values
	yield(get_tree(), "idle_frame")
	var color_value: Color = Global.config_cache.get_value(
		_slots[BUTTON_LEFT].kname, "color", Color.black
	)
	assign_color(color_value, BUTTON_LEFT, false)
	color_value = Global.config_cache.get_value(_slots[BUTTON_RIGHT].kname, "color", Color.white)
	assign_color(color_value, BUTTON_RIGHT, false)


func set_tool(name: String, button: int) -> void:
	var slot = _slots[button]
	var panel: Node = _panels[button]
	var node: Node = load(_tools[name]).instance()
	node.name = name
	node.tool_slot = slot
	slot.tool_node = node
	slot.button = button
	panel.add_child(slot.tool_node)


func assign_tool(name: String, button: int) -> void:
	var slot = _slots[button]
	var panel: Node = _panels[button]

	if slot.tool_node != null:
		if slot.tool_node.name == name:
			return
		panel.remove_child(slot.tool_node)
		slot.tool_node.queue_free()

	set_tool(name, button)
	update_tool_buttons()
	update_tool_cursors()
	Global.config_cache.set_value(slot.kname, "tool", name)


func default_color() -> void:
	assign_color(Color.black, BUTTON_LEFT)
	assign_color(Color.white, BUTTON_RIGHT)


func swap_color() -> void:
	var left = _slots[BUTTON_LEFT].color
	var right = _slots[BUTTON_RIGHT].color
	assign_color(right, BUTTON_LEFT, false)
	assign_color(left, BUTTON_RIGHT, false)


func assign_color(color: Color, button: int, change_alpha := true) -> void:
	var c: Color = _slots[button].color
	# This was requested by Issue #54 on GitHub
	if color.a == 0 and change_alpha:
		if color.r != c.r or color.g != c.g or color.b != c.b:
			color.a = 1
	_slots[button].color = color
	Global.config_cache.set_value(_slots[button].kname, "color", color)
	emit_signal("color_changed", color, button)


func get_assigned_color(button: int) -> Color:
	return _slots[button].color


func set_button_size(button_size: int) -> void:
	if button_size == Global.ButtonSize.SMALL:
		for t in _tool_buttons.get_children():
			t.rect_min_size = Vector2(24, 24)
			t.get_node("ToolIcon").rect_position = Vector2.ONE
			t.get_node("BackgroundLeft").rect_size.x = 12
			t.get_node("BackgroundRight").rect_size.x = 12
			t.get_node("BackgroundRight").rect_position = Vector2(24, 24)
		_tool_buttons.get_parent().rect_position.x = 9
	else:
		for t in _tool_buttons.get_children():
			t.rect_min_size = Vector2(32, 32)
			t.get_node("ToolIcon").rect_position = Vector2.ONE * 5
			t.get_node("BackgroundLeft").rect_size.x = 16
			t.get_node("BackgroundRight").rect_size.x = 16
			t.get_node("BackgroundRight").rect_position = Vector2(32, 32)
		_tool_buttons.get_parent().rect_position.x = 6

	# It doesn't actually set the size to zero, it just resets it
	_tool_buttons.get_parent().rect_size = Vector2.ZERO
	_tool_buttons.columns = 1
	_tool_buttons.get_parent().get_parent().get_parent().get_parent().split_offset = 0


func update_tool_buttons() -> void:
	for child in _tool_buttons.get_children():
		var left_background: NinePatchRect = child.get_node("BackgroundLeft")
		var right_background: NinePatchRect = child.get_node("BackgroundRight")
		left_background.visible = _slots[BUTTON_LEFT].tool_node.name == child.name
		right_background.visible = _slots[BUTTON_RIGHT].tool_node.name == child.name


func update_tool_cursors() -> void:
	var left_image = load(
		"res://assets/graphics/tools/cursors/%s.png" % _slots[BUTTON_LEFT].tool_node.name.to_lower()
	)
	Global.left_cursor.texture = left_image
	var right_image = load(
		(
			"res://assets/graphics/tools/cursors/%s.png"
			% _slots[BUTTON_RIGHT].tool_node.name.to_lower()
		)
	)
	Global.right_cursor.texture = right_image


func draw_indicator() -> void:
	if Global.left_square_indicator_visible:
		_slots[BUTTON_LEFT].tool_node.draw_indicator()
	if Global.right_square_indicator_visible:
		_slots[BUTTON_RIGHT].tool_node.draw_indicator()


func draw_preview() -> void:
	_slots[BUTTON_LEFT].tool_node.draw_preview()
	_slots[BUTTON_RIGHT].tool_node.draw_preview()


func handle_draw(position: Vector2, event: InputEvent) -> void:
	if not (Global.can_draw and Global.has_focus):
		return

	var draw_pos := position
	if Global.mirror_view:
		draw_pos.x = Global.current_project.size.x - position.x - 1

	if event is InputEventWithModifiers:
		control = event.control
		shift = event.shift
		alt = event.alt

	if event is InputEventMouseButton:
		if event.button_index in [BUTTON_LEFT, BUTTON_RIGHT]:
			if event.pressed and _active_button == -1:
				_active_button = event.button_index
				_slots[_active_button].tool_node.draw_start(draw_pos)
			elif not event.pressed and event.button_index == _active_button:
				_slots[_active_button].tool_node.draw_end(draw_pos)
				_active_button = -1

	if event is InputEventMouseMotion:
		pen_pressure = event.pressure
		if Global.pressure_sensitivity_mode == Global.PressureSensitivity.NONE:
			pen_pressure = 1.0

		if not position.is_equal_approx(_last_position):
			_last_position = position
			_slots[BUTTON_LEFT].tool_node.cursor_move(position)
			_slots[BUTTON_RIGHT].tool_node.cursor_move(position)
			if _active_button != -1:
				_slots[_active_button].tool_node.draw_move(draw_pos)

	var project: Project = Global.current_project
	var text := "[%s×%s]" % [project.size.x, project.size.y]
	if Global.has_focus:
		text += "    %s, %s" % [position.x, position.y]
	if not _slots[BUTTON_LEFT].tool_node.cursor_text.empty():
		text += "    %s" % _slots[BUTTON_LEFT].tool_node.cursor_text
	if not _slots[BUTTON_RIGHT].tool_node.cursor_text.empty():
		text += "    %s" % _slots[BUTTON_RIGHT].tool_node.cursor_text
	Global.cursor_position_label.text = text