extends Node3D
class_name FPSCameraRig

## FPS camera rig — handles mouse look, head bob, FOV kick, wall-run tilt.
## Attach as child of the CharacterBody3D player. Camera3D is a child of this node.

@export var sensitivity: float = 0.002
@export var pitch_limit: float = 89.0

var params: MovementParams
var camera: Camera3D
var _bob_timer: float = 0.0
var _target_tilt: float = 0.0
var _current_tilt: float = 0.0
var _target_fov: float = 90.0
var _weapon_fov_override: float = -1.0


func _ready() -> void:
	Input.set_mouse_mode(Input.MOUSE_MODE_CAPTURED)
	camera = get_node_or_null("Camera3D")
	if camera and params:
		camera.fov = params.base_fov
		_target_fov = params.base_fov
	# Explicitly enable callbacks — set_script() at runtime doesn't auto-register them
	set_process_input(true)
	set_process(true)


func _input(event: InputEvent) -> void:
	if event is InputEventMouseMotion and Input.get_mouse_mode() == Input.MOUSE_MODE_CAPTURED:
		var is_ads = camera and camera.fov < params.base_fov - 5.0
		var sens = SettingsManager.ads_sensitivity if is_ads else SettingsManager.mouse_sensitivity
		# Yaw: rotate the player (parent)
		get_parent().rotate_y(-event.relative.x * sens)
		# Pitch: rotate this pivot
		rotation.x = clampf(rotation.x - event.relative.y * sens, deg_to_rad(-pitch_limit), deg_to_rad(pitch_limit))

	# Toggle mouse capture with Escape
	if event is InputEventKey and event.pressed and event.keycode == KEY_ESCAPE:
		if Input.get_mouse_mode() == Input.MOUSE_MODE_CAPTURED:
			Input.set_mouse_mode(Input.MOUSE_MODE_VISIBLE)
		else:
			Input.set_mouse_mode(Input.MOUSE_MODE_CAPTURED)


func _process(delta: float) -> void:
	if not camera or not params:
		return

	var player: CharacterBody3D = get_parent() as CharacterBody3D
	if not player:
		return

	# ── FOV kick ──────────────────────────────────────────────────────────
	_target_fov = params.base_fov
	var hspeed := Vector2(player.velocity.x, player.velocity.z).length()

	# Smoothly scale FOV based on speed above walking speed
	var speed_factor = clampf((hspeed - params.walk_speed) / (params.walk_speed * 0.5), 0.0, 1.0)
	_target_fov = lerpf(params.base_fov, params.dash_fov, speed_factor)
		
	if _weapon_fov_override > 0.0:
		_target_fov = _weapon_fov_override

	camera.fov = lerpf(camera.fov, _target_fov, 1.0 - exp(-params.fov_lerp_speed * delta))

	# ── Head bob ──────────────────────────────────────────────────────────
	var sm = player.get_node_or_null("MovementStateMachine")
	var is_sliding = sm and sm.current_state == "slide"
	
	if player.is_on_floor() and hspeed > 1.0 and not is_sliding:
		_bob_timer += delta * params.head_bob_frequency * (hspeed / params.walk_speed)
		var bob_y := sin(_bob_timer) * params.head_bob_amplitude
		var bob_x := cos(_bob_timer * 0.5) * params.head_bob_amplitude * 0.5
		camera.position.y = lerp(camera.position.y, bob_y, 0.3)
		camera.position.x = lerp(camera.position.x, bob_x, 0.3)
	else:
		_bob_timer = 0.0
		camera.position.y = lerp(camera.position.y, 0.0, 0.15)
		camera.position.x = lerp(camera.position.x, 0.0, 0.15)

	# ── Wall-run tilt ─────────────────────────────────────────────────────
	_current_tilt = lerpf(_current_tilt, _target_tilt, 1.0 - exp(-params.wall_run_tilt_speed * delta))
	camera.rotation.z = deg_to_rad(_current_tilt)


## Called by the movement system to set wall-run tilt direction.
## side: -1.0 (left wall), 1.0 (right wall), 0.0 (no tilt)
func set_wall_tilt(side: float) -> void:
	if params:
		_target_tilt = side * params.wall_run_tilt_angle
	else:
		_target_tilt = side * 12.0

func set_weapon_fov(fov: float) -> void:
	_weapon_fov_override = fov


## Called to reset tilt (e.g., on landing).
func clear_wall_tilt() -> void:
	_target_tilt = 0.0