extends Node3D
## NAF Phantom II (shrike). Godot 4.7. Units: 1 m.
## Axes: nose +Z, belly -Y, starboard +X. The torch exhausts -Z.
## rcs_direction uses those axes. Nose thrust is +Z. Dorsal thrust is +Y.
## See PARTICLE_FX.md.

const Fx = preload("res://naf_fx.gd")

@export_range(0.0, 1.0) var gear_deploy := 1.0 : set = set_gear_deploy
@export_range(0.0, 1.0) var canopy_open := 0.0 : set = set_canopy_open
@export_range(0.0, 1.0) var throttle := 0.0
@export var drive_on := false
@export_enum("Off", "Nose", "Tail", "Starboard", "Port", "Dorsal", "Ventral") var rcs_direction := 0
@export var pdc_fire := false
@export var chaff_fire := false
@export var cabin_dim := false : set = set_cabin_dim

var _time := 0.0
var _spool := 0.0
var _drive_socket: Node3D
var _drive_core: Node3D
var _drive_sheath: Node3D
var _drive_light: SpotLight3D
var _rcs: Array[Node3D] = []
var _muzzles: Array[Node3D] = []
var _tracers: Array[Dictionary] = []
var _tracer_pool: Array[MeshInstance3D] = []
var _tracer_mesh: ArrayMesh
var _tracer_mat: StandardMaterial3D
var _chaff: Array[GPUParticles3D] = []
var _cabin_ready := false
var _cabin_lights: Array[Light3D] = []
var _cabin_rest: Array[Dictionary] = []

const _RCS_THRUST := [
	Vector3.ZERO,
	Vector3(0, 0, 1),
	Vector3(0, 0, -1),
	Vector3(1, 0, 0),
	Vector3(-1, 0, 0),
	Vector3(0, 1, 0),
	Vector3(0, -1, 0),
]

func _ready() -> void:
	_seek("gear_deploy", gear_deploy)
	_arm_fx()
	_collect_cabin()
	set_physics_process(true)

func _physics_process(delta: float) -> void:
	_time += delta
	var power := throttle if drive_on else 0.0
	var spool_target := 1.0 if power > 0.04 else 0.0
	_spool = Fx.smooth(_spool, spool_target, delta, 0.26 if spool_target > 0.0 else 0.07)
	var plume := power * _spool
	if _drive_core:
		Fx.set_spear(_drive_core, plume, 1.0, _time)
		Fx.set_spear(_drive_sheath, plume * 0.82, 1.0, _time)
		if _drive_light:
			_drive_light.light_energy = plume * 5.0
	var thrust: Vector3 = _RCS_THRUST[clampi(rcs_direction, 0, _RCS_THRUST.size() - 1)]
	var ship := global_transform.basis
	for ribbon in _rcs:
		var want := 0.0
		if thrust != Vector3.ZERO:
			var exhaust: Vector3 = ship.inverse() * ribbon.global_transform.basis.y
			if exhaust.dot(-thrust) > 0.7:
				want = 1.0
		var burn := float(ribbon.get_meta("burn"))
		burn = Fx.smooth(burn, want, delta, 0.08 if want > burn else 0.14)
		ribbon.set_meta("burn", burn)
		Fx.set_spear(ribbon, burn, 1.0, _time)
	for cloud in _chaff:
		cloud.emitting = chaff_fire
	_step_pdc(delta)

func set_cabin_dim(v: bool) -> void:
	cabin_dim = v
	if _cabin_ready:
		for i in _cabin_lights.size():
			var lamp := _cabin_lights[i]
			var rest: Dictionary = _cabin_rest[i]
			lamp.light_energy = float(rest.energy) * (0.16 if cabin_dim else 1.0)
			lamp.light_color = rest.color

func _collect_cabin() -> void:
	for n in find_children("*", "Light3D", true, false):
		var nm := String(n.name)
		if nm.begins_with("PointLight_") or nm.begins_with("CabinLamp") or nm == "CabinFill":
			_cabin_lights.append(n)
			_cabin_rest.append({"energy": n.light_energy, "color": n.light_color})
	_cabin_ready = true

func set_gear_deploy(v: float) -> void:
	gear_deploy = v
	_seek("gear_deploy", v)

func set_canopy_open(v: float) -> void:
	canopy_open = v
	_seek("canopy_open", v)

func _seek(clip: StringName, t: float) -> void:
	var ap := get_node_or_null("AnimationPlayer") as AnimationPlayer
	if ap == null:
		ap = find_child("AnimationPlayer", true, false) as AnimationPlayer
	if ap == null or not ap.has_animation(clip):
		return
	ap.play(clip)
	ap.seek(clampf(t, 0.0, 1.0) * ap.get_animation(clip).length, true)
	ap.pause()

func _arm_fx() -> void:
	_tracer_mesh = Fx.tracer_mesh()
	_tracer_mat = Fx.tracer_mat()
	var drive := find_child("Vfx_DrivePlume", true, false) as Node3D
	if drive:
		_drive_socket = drive
		_drive_core = Fx.spear(drive, 22.0, 0.68, Color(0.957, 0.973, 1.0, 0.95), Color(0.47, 0.71, 1.0, 0.35), Color(0.24, 0.47, 1.0, 0.0), 0.92, 3, 1.0, "DriveCore")
		_drive_sheath = Fx.spear(drive, 14.0, 1.7, Color(0.353, 0.659, 1.0, 0.9), Color(0.17, 0.47, 1.0, 0.35), Color(0.08, 0.22, 0.55, 0.0), 0.5, 3, 2.0, "DriveSheath")
		_drive_light = Fx.spot(drive, 0.3, Color(0.773, 0.863, 1.0), 0.35, 7.5, 2.0)
	for n in find_children("*", "Node3D", true, false):
		var nm := String(n.name)
		if nm.begins_with("Vfx_RCS_"):
			_rcs.append(Fx.spear(n, 1.2, 0.09, Color(0.863, 0.937, 1.0, 0.95), Color(0.41, 0.67, 1.0, 0.35), Color(0.25, 0.45, 0.8, 0.0), 0.82, 2, 1.0, "Spear"))
		elif nm.begins_with("PDT_") and nm.ends_with("_Muzzle"):
			_muzzles.append(n)
			n.set_meta("acc", randf() * 0.02)
		elif nm == "Vfx_Chaff":
			_chaff.append(Fx.chaff(n))

func _step_pdc(delta: float) -> void:
	if pdc_fire:
		for mz in _muzzles:
			var acc := float(mz.get_meta("acc")) - delta
			var shots := 0
			while acc <= 0.0 and shots < 2 and _tracers.size() < 40:
				acc += 1.0 / 42.0
				shots += 1
				var mesh := _take_tracer()
				var world_dir: Vector3 = (mz.global_transform.basis * Fx.exhaust_local(mz)).normalized()
				var shot := Fx.cone(world_dir, 1.15)
				var origin := mz.global_position + world_dir * 0.18
				var local_dir: Vector3 = global_transform.basis.inverse() * shot
				mesh.position = to_local(origin)
				mesh.basis = Fx.basis_y(local_dir)
				mesh.scale = Vector3(1, randf_range(1.5, 2.3), 1)
				mesh.visible = true
				_tracers.append({"mesh": mesh, "dir": local_dir, "life": randf_range(0.12, 0.2), "speed": randf_range(90.0, 140.0)})
			mz.set_meta("acc", acc)
	for i in range(_tracers.size() - 1, -1, -1):
		var t: Dictionary = _tracers[i]
		t.life = float(t.life) - delta
		var mesh := t.mesh as MeshInstance3D
		if float(t.life) <= 0.0:
			mesh.visible = false
			_tracer_pool.append(mesh)
			_tracers.remove_at(i)
			continue
		mesh.position += (t.dir as Vector3) * float(t.speed) * delta

func _take_tracer() -> MeshInstance3D:
	if _tracer_pool.size() > 0:
		return _tracer_pool.pop_back()
	var m := MeshInstance3D.new()
	m.mesh = _tracer_mesh
	m.material_override = _tracer_mat
	m.cast_shadow = GeometryInstance3D.SHADOW_CASTING_SETTING_OFF
	m.visible = false
	add_child(m)
	return m