@tool
class_name TerrainEditingControls
extends VBoxContainer

enum ToolMode { HEIGHT, FLATTEN, PAINT, ERASE }
enum ToolShape { CORNER, CIRCLE, SQUARE }

@onready var tool_mode_buttons     : Array[Button] = [ $Height, $Flatten, $Paint, $Erase ]
@onready var tool_shape_buttons    : Array[Button] = [ $Corner, $Circle, $Square ]
@onready var paint_texture_buttons : Array[Button] = [ $Grass, $Dirt, $Rock, $Sand ]

@onready var draw_size_label    : Label  = $SizeLabel
@onready var draw_size_slider   : Slider = $SizeSlider
@onready var raise_lower_toggle : Button = $RaiseLower
@onready var connected_toggle   : Button = $Connected

@onready var corner_texture_default : Texture2D = preload("icons/corner.png")
@onready var corner_texture_tile    : Texture2D = preload("icons/corner_tile.png")


## Gets or sets the currently active tool mode.
var tool_mode : ToolMode:
	get: return index_of_pressed(tool_mode_buttons)
	set(value): set_pressed(tool_mode_buttons, value); tool_mode_changed()
## Gets or sets the currently selected tool shape.
var tool_shape : ToolShape:
	get: return index_of_pressed(tool_shape_buttons)
	set(value): set_pressed(tool_shape_buttons, value); tool_shape_changed()
## Gets or sets the currently selected texture to paint with.
var texture : int:
	get: return index_of_pressed(paint_texture_buttons) + 1
	set(value): set_pressed(paint_texture_buttons, value - 1)
## Gets or sets the current draw size for CIRCLE or SQUARE shapes.
var draw_size : int:
	get: return roundi(-draw_size_slider.value)
	set(value): draw_size_slider.value = -value

## Gets whether the raise/lower button is currently active.
var is_raise : bool:
	get: return raise_lower_toggle.button_pressed
## Gets whether the raise/lower button is currently active.
var is_connected : bool:
	get: return connected_toggle.button_pressed


func _ready() -> void:
	# Update 'tool_mode', 'tool_shape' or 'texture' when any of the buttons are pressed.
	for i in len(tool_mode_buttons    ): tool_mode_buttons    [i].pressed.connect(func(): tool_mode  = i    )
	for i in len(tool_shape_buttons   ): tool_shape_buttons   [i].pressed.connect(func(): tool_shape = i    )
	for i in len(paint_texture_buttons): paint_texture_buttons[i].pressed.connect(func(): texture    = i + 1)

	# Update 'draw_size_label' whenever the slider changes.
	draw_size_slider.value_changed.connect(func(_value):
		draw_size_label.text = str(draw_size))


func tool_mode_changed() -> void:
	var is_height  := (tool_mode == ToolMode.HEIGHT)
	var is_flatten := (tool_mode == ToolMode.FLATTEN)
	var is_paint   := (tool_mode == ToolMode.PAINT)
	var is_erase   := (tool_mode == ToolMode.ERASE)

	# In 'PAINT' and 'ERASE' mode, 'CORNER' affects a single tile regardless of 'draw_size'.
	# This changes the button's icon to a small square to communicate that.
	tool_shape_buttons[0].icon = corner_texture_tile if is_paint or is_erase else corner_texture_default

	# Enable texture buttons only in 'PAINT' mode.
	for button in paint_texture_buttons: button.disabled = !is_paint

	# Enable raise/lower toggle only in 'HEIGHT' mode.
	raise_lower_toggle.disabled = !is_height

	# Enable connected toggle only in 'HEIGHT' or 'FLATTEN' mode.
	connected_toggle.disabled = !(is_height or is_flatten)

func tool_shape_changed() -> void:
	var is_corner := (tool_shape == ToolShape.CORNER)
	draw_size_slider.editable = !is_corner;


## Returns the index of the first pressed (toggled on) button.
func index_of_pressed(buttons: Array[Button]) -> int:
	for i in len(buttons):
		var button := buttons[i]
		if button.button_pressed:
			return i
	return 0

## Sets the pressed state (toggled on) of the button
## with the specified index, unsetting all others.
func set_pressed(buttons: Array[Button], value: int) -> void:
	for i in len(buttons):
		var button     := buttons[i]
		var is_pressed := (value == i)
		button.button_pressed = is_pressed
		button.flat = !is_pressed