extends CharacterBody3D

# Member variables
const QUAKE = 0.0625
const g = -800 * QUAKE
const MAX_SPEED = 320 * QUAKE
const FRICTION = 4# * QUAKE
const STOP_SPEED = 100 * QUAKE
const ACCEL= 10# * QUAKE
const FORWARD_SPEED = 400 * QUAKE
const SIDE_SPEED = 350 * QUAKE
const UP_SPEED = 270 * QUAKE

# const DEACCEL= 8
# const MAX_SLOPE_ANGLE = 30

@onready
var camera = $CSGMesh3D/Camera3D

var _paused = false
var _noclip = false


func _ready():
	Input.set_mouse_mode(Input.MOUSE_MODE_CAPTURED)


func _physics_process(delta):
	# Shamelessly stolen code from quake :)
	
	var fmove = 0.0
	var smove = 0.0
	var upmove = 0.0

	if Input.is_action_pressed("move_forward"):
		fmove += -FORWARD_SPEED
	if Input.is_action_pressed("move_backwards"):
		fmove += FORWARD_SPEED
	if Input.is_action_pressed("move_left"):
		smove += -SIDE_SPEED
	if Input.is_action_pressed("move_right"):
		smove += SIDE_SPEED
	if Input.is_action_pressed("jump"):
		upmove += UP_SPEED
	if Input.is_action_pressed("run"):
		fmove *= 2.0
		smove *= 2.0
	
	var wishvel = Vector3()
	var cam_xform: Transform3D = camera.get_global_transform()
	var cam_basis: Basis = cam_xform.basis
	
	wishvel = cam_basis.z * fmove + cam_basis.x * smove
	
	if _noclip:
		wishvel.y += upmove
#	else:
#		wishvel.y = upmove
	
	var wishdir = wishvel.normalized()
	var wishspeed = wishvel.length()
	
	if wishspeed > MAX_SPEED:
		wishvel *= MAX_SPEED / wishspeed
		wishspeed = MAX_SPEED
	
	if   is_on_floor():
		velocity.y += upmove
	var vel = velocity
	if _noclip:
		vel = wishvel
	elif is_on_floor():
		vel = _apply_friction(vel, delta)
		vel = _apply_accel(vel, wishdir, wishspeed, delta)
	else:
		vel = _apply_air_accel(vel, wishvel, wishspeed, delta)
		
	if not _noclip:
		vel.y += g * delta
		
	velocity = vel
	move_and_slide()
	
	$Ball.global_position = camera.global_position - camera.global_transform.basis.z * 2.0
	
func _apply_friction(vel: Vector3, delta: float):
	var speed = sqrt(vel.x ** 2 + vel.z ** 2)
	if(speed == 0.0): return vel
	
	# TODO: edge detect friction?
	var friction = FRICTION
	
	var control = 0.0
	if speed < STOP_SPEED:
		control = STOP_SPEED
	else:
		control = speed
	
	var newspeed = speed - delta * control * friction
	
	if newspeed < 0.0:
		newspeed = 0.0
	
	newspeed /= speed
	
	return vel * newspeed
	
func _apply_accel(vel: Vector3, wishdir: Vector3, wishspeed: float, delta: float):
	var currentspeed = vel.dot(wishdir)
	var addspeed = wishspeed - currentspeed
	if addspeed <= 0.0:
		return vel
		
	var accelspeed = ACCEL * delta * wishspeed
	if accelspeed > addspeed:
		accelspeed = addspeed
	
	return vel + accelspeed * wishdir
	
func _apply_air_accel(vel: Vector3, wishvel: Vector3, wishspeed: float, delta: float):
	var wishveloc = wishvel.normalized()
	var wishspd = wishvel.length()
	
	if wishspd > 30 * QUAKE:
		wishspd = 30 * QUAKE
	
	var currentspeed = vel.dot(wishveloc)
	var addspeed = wishspd - currentspeed
	if addspeed <= 0:
		return vel
		
	var accelspeed = ACCEL * wishspeed * delta
	if accelspeed > addspeed:
		accelspeed = addspeed
		
	return vel + accelspeed * wishveloc

func _input(event):
	if event.is_action_pressed("pause"):
		_paused = not _paused
		if _paused:
			Input.set_mouse_mode(Input.MOUSE_MODE_VISIBLE)
		else:
			Input.set_mouse_mode(Input.MOUSE_MODE_CAPTURED)
				
	if _paused: return
	
	if event.is_action_pressed('noclip'):
		_noclip = not _noclip
		if _noclip:
			$CollisionShape3D.disabled = true
		else:
			$CollisionShape3D.disabled = false
	
	# Check for mouse motion input
	if event is InputEventMouseMotion:
		rotation.y += -event.relative.x * 0.005
		camera.rotation.x += -event.relative.y * 0.005
		camera.rotation.x = clamp(camera.rotation.x, deg_to_rad(-70), deg_to_rad(70))
		
	if event.is_action_pressed("interact"):
		var space_state = get_world_3d().direct_space_state
		# use global coordinates, not local to node
		var query = PhysicsRayQueryParameters3D.create(camera.global_position, $Ball.global_position)
		# Don't collide with ourselves
		query.exclude = [self]
		var result = space_state.intersect_ray(query)
		if result.has('collider'):
			var other: Node3D = result.collider
			if other.has_method('interact'):
				other.interact(self)