extends "res://scripts/creatures/creature.gd"
## A crow (docs/PROGRESSION_DESIGN.md §4): sent by thieves.gd, by day, for
## food left lying on the ground. It flies in, lands on it and pecks it away
## a bit at a time, and takes off again if anyone comes within SCARE. Then
## it flies off over the trees and is gone. A closed chest keeps food safe.
## An arrow brings it down (feathers).

const SCARE := 7.0
const PECK_EVERY := 3.0
const FLY_SPEED := 9.0
const CRUISE := 7.0             ## height above the ground while flying in
const LEAVE_HEIGHT := 14.0

var thieves: Node               ## thieves.gd
var food: Node3D = null
var _goal := Vector3.ZERO
var _peck_anim := 0.0

func display_name() -> String:
	return "Crow"

func interact_prompt(p: Node) -> String:
	if is_dead():
		return "Crow  [E] Pluck"
	return {"peck": "Crow (pecking at your food!)", "fly": "Crow (circling your food)"}.get(state, "Crow")

func _flying() -> bool:
	return state in ["fly", "fly_off"]

func _think(dt: float) -> void:
	match state:
		"fly":
			if not thieves.still_there(food) or thieves.watched(food.global_position, SCARE):
				_leave()
				return
			_goal = food.global_position
			var ground: float = terrain.sample_height(global_position.x, global_position.z)
			if Vector2(_goal.x - global_position.x, _goal.z - global_position.z).length() < 0.35 and global_position.y - ground < 0.15:
				state = "peck"
				_state_t = PECK_EVERY
				thieves.landed(self, food)
		"peck":
			if not thieves.still_there(food) or thieves.watched(global_position, SCARE):
				_leave()
				return
			_state_t -= dt
			if _state_t <= 0.0:
				_state_t = PECK_EVERY
				_peck_anim = 0.4
				if thieves.peck(self, food):   # the last of it
					_leave()
		"fly_off":
			if thieves.out_of_sight(global_position):
				thieves.gone(self)
		_:
			_leave()

func _leave() -> void:
	state = "fly_off"
	food = null
	var p: Node3D = world.nearest_player(global_position)
	var away := Vector3(1, 0, 0)
	if p != null:
		away = global_position - p.global_position
		away.y = 0.0
		if away.length() < 0.1:
			away = Vector3(1, 0, 0)
	_goal = global_position + away.normalized() * 120.0

## Straight-line flight (no steering round trees: it flies over them).
func _move(dt: float) -> void:
	if not _flying():
		speed = 0.0
		return
	var to := _goal - global_position
	to.y = 0.0
	var flat := to.length()
	var spd := FLY_SPEED
	if state == "fly" and flat < 6.0:
		spd = maxf(flat * 1.5, 1.2)   # glide in to land
	var p := global_position
	if flat > 0.02:
		yaw = rotate_toward(yaw, atan2(-to.x, -to.z), 8.0 * dt)
		p += to / flat * minf(spd * dt, flat)
	var ground: float = terrain.sample_height(p.x, p.z)
	var alt := LEAVE_HEIGHT
	if state == "fly":
		alt = CRUISE * clampf((flat - 0.3) / 8.0, 0.0, 1.0)
	p.y = maxf(move_toward(global_position.y, maxf(ground, terrain.water_level) + alt, 5.0 * dt), ground)
	global_position = p
	rotation.y = yaw
	speed = spd

## Wings out and flapping in the air, folded on the ground; a dip of the
## head when it pecks.
func _animate(dt: float) -> void:
	var flying := _flying() or (puppet and speed > 0.5)
	_phase += dt * 16.0
	for l in _legs:
		var s := -1.0 if l.position.x < 0.0 else 1.0
		l.rotation.z = s * ((PI * 0.5 + sin(_phase) * 0.7) if flying else 0.2)
	_peck_anim = maxf(_peck_anim - dt, 0.0)
	if is_dead():
		return
	_visual.rotation.x = 0.5 * sin(_peck_anim / 0.4 * PI) if state == "peck" else 0.0

func _react(_from: Vector3) -> void:
	_leave()

## Brought down out of the air: it lands where it fell.
func _die(from: Vector3) -> void:
	super._die(from)
	var p := global_position
	p.y = terrain.sample_height(p.x, p.z)
	global_position = p