class_name Avatar
extends Node2D
## The local player's figure. It moves outside the lockstep simulation; only
## its pickaxe hits become commands. `art` draws it, stepping while it walks
## and facing the way it went last.

## Walking speed: five tiles per second.
const SPEED := 5.0 * GridMotion.TILE_SIZE
const RADIUS := 5.0
## Longest frame that moves the figure in one go. Longer frames are cut, so
## that the figure cannot pass through a wall after a stall.
const MAX_STEP_SECONDS := 0.1
## How far the step of a walking figure turns per pixel, in radians: about
## two steps per second at walking speed.
const STEP_PER_PIXEL := 0.16

## Callable(x: int, y: int) -> bool that says whether a tile can be walked on.
var is_walkable: Callable
var art: Art
## The number of the player the figure belongs to, for its colour, or -1
## before the player is in the world.
var player := -1
## 1.0 while the figure faces right, -1.0 while it faces left.
var facing := 1.0
## Grows while the figure walks; the styles swing the steps by it.
var step := 0.0
## True while the figure walked in the last frame.
var moving := false


## Where a figure standing at `at` is drawn: a tile wide and one and a half
## tiles tall, with its feet just below its body, so that it stands upright
## in its tile.
static func figure_rect(at: Vector2) -> Rect2:
	var size := GridMotion.TILE_SIZE
	return Rect2(at.x - size / 2.0, at.y + RADIUS + 1.0 - size * 1.5, size, size * 1.5)


func _process(delta: float) -> void:
	walk(Input.get_vector("move_left", "move_right", "move_up", "move_down"), delta)


## Moves the figure in `direction` for `delta` seconds, sliding along walls.
func walk(direction: Vector2, delta: float) -> void:
	var was_moving := moving
	moving = false
	if direction == Vector2.ZERO or not is_walkable.is_valid():
		if was_moving:
			queue_redraw()
		return
	var motion := direction * SPEED * minf(delta, MAX_STEP_SECONDS)
	var before := position
	position = GridMotion.move(position, motion, RADIUS, is_walkable)
	var walked := position.distance_to(before)
	moving = walked > 0.0
	step += walked * STEP_PER_PIXEL
	if direction.x != 0.0:
		facing = signf(direction.x)
	queue_redraw()


func _draw() -> void:
	if art != null:
		art.draw(self, Art.FIGURE, figure_rect(Vector2.ZERO), {"player": player, "facing": facing, "step": step, "moving": moving})