extends CharacterBody3D

@export var camera: Camera3D

var SPEED = 2.0
const JUMP_VELOCITY = 4.5
const MOUSE_SENSITIVITY = 0.004

const ROTATION_SPEED := 4.0  # How fast to interpolate (higher = snappier)
var target_rotation := Vector2.ZERO  # x = pitch, y = yaw


func _ready() -> void:
	assert(camera != null, "Forgot to set camera in editor")
	Input.mouse_mode = Input.MOUSE_MODE_CAPTURED

	# Initialize target rotation from current rotation
	target_rotation.y = rotation.y
	target_rotation.x = camera.rotation.x


func _unhandled_input(event: InputEvent) -> void:
	if event is InputEventMouseMotion and Input.mouse_mode == Input.MOUSE_MODE_CAPTURED:
		target_rotation.y -= event.relative.x * MOUSE_SENSITIVITY
		target_rotation.x -= event.relative.y * MOUSE_SENSITIVITY
		target_rotation.x = clamp(target_rotation.x, deg_to_rad(-80), deg_to_rad(80))

func _process(delta: float) -> void:
	# Smoothly interpolate current rotation toward target
	rotation.y = lerp_angle(rotation.y, target_rotation.y, delta * ROTATION_SPEED)
	camera.rotation.x = lerp_angle(camera.rotation.x, target_rotation.x, delta * ROTATION_SPEED)
	

const ACCELERATION := 10.0
const DECELERATION := 6.0


var input_direction := Vector3.ZERO
var target_velocity := Vector3.ZERO

func _get_input_direction() -> Vector3:
	var direction := Vector3.ZERO
	if Input.is_key_pressed(KEY_LEFT) or Input.is_key_pressed(KEY_A):
		direction.x -= 1
	if Input.is_key_pressed(KEY_RIGHT) or Input.is_key_pressed(KEY_D):
		direction.x += 1
	if Input.is_key_pressed(KEY_UP) or Input.is_key_pressed(KEY_W):
		direction.z += 1
	if Input.is_key_pressed(KEY_DOWN) or Input.is_key_pressed(KEY_S):
		direction.z -= 1
	return direction.normalized()

func _physics_process(delta: float) -> void:
	# Get input direction relative to player orientation
	input_direction = _get_input_direction()
	
	var basis := global_transform.basis
	var forward := -basis.z.normalized()
	var right := basis.x.normalized()
	
	# Desired horizontal movement direction in world space
	var desired_velocity : Vector3 = (right * input_direction.x + forward * input_direction.z) * SPEED
	desired_velocity.y = 0  # Only horizontal
	
	# Smooth acceleration/deceleration
	var accel := DECELERATION if input_direction == Vector3.ZERO else ACCELERATION
	target_velocity.x = lerp(target_velocity.x, desired_velocity.x, accel * delta)
	target_velocity.z = lerp(target_velocity.z, desired_velocity.z, accel * delta)
	
	# Preserve existing vertical velocity
	if not is_on_floor():
		target_velocity.y += get_gravity().y * delta
	else:
		target_velocity.y = 0
		if Input.is_action_just_pressed("ui_accept"):
			target_velocity.y = JUMP_VELOCITY
	
	# Apply movement
	velocity = target_velocity
	move_and_slide()