extends Node3D
## One Ancient (G2 "Mondherz"): the monumental heart of a base. Reads the authoritative HP
## and shows four states - stable, unstable (cracks, uneasy energy), critical (heavy cracks,
## leaking energy, a leaning blade, a fallen fragment, sparks and smoke) and the collapse into
## a lasting ruin. The collapse is presentation only: the match has already been decided and
## processed when it starts, and it never delays anything.

const Materials = preload("res://scripts/luneraria/view/lune_materials.gd")
const Fx = preload("res://scripts/luneraria/view/lune_fx.gd")
enum State { STABLE, UNSTABLE, CRITICAL, COLLAPSING, FALLEN }
const SCENE_PATH := "res://assets/luneraria/g2/ancient.glb"
const UNSTABLE_BELOW: float = .605
const CRITICAL_BELOW: float = .305
const COLLAPSE_SECONDS: float = 2.8
const CRYSTAL_Y: float = 4.7
const BLADE_ANGLES: Array[float] = [0.0, PI * .5, PI, PI * 1.5]
## Dais steps (outer radius, top height above the plaza) - figures are lifted onto them.
const DAIS_STEPS: Array = [[4.0, .05], [3.4, .1], [2.8, .15]]
## Occlusion fade (G2): the blades, rings and heart above this height may thin out.
const FADE_FLOOR: float = 2.4
const OCCLUDER_RADIUS: float = 3.2
const TOP: float = 10.4
static var _scene: PackedScene

var building_id: String = ""
var team: int = 0
var state: int = State.STABLE
var fraction: float = 1.0
var fade_target: float = 0.0
var seed_value: float = 0.0
var light: OmniLight3D
var crystal: Node3D
var satellites: Array[Node3D] = []
var fragments: Array[Node3D] = []
var rings: Array[Node3D] = []
var blades: Array[Node3D] = []
var crown: Node3D
var crest: Node3D
var _parts: Dictionary = {}
var _rest: Dictionary = {}
var _instances: Array = []
var _structure: Array = []
var _crystals: Array = []
var _cloth: Array = []
var _ruin: Array = []
var _sent: Dictionary = {}
var _motes: GPUParticles3D
var _sparks: GPUParticles3D
var _smoke: GPUParticles3D
var _dust: GPUParticles3D
var _burst: GPUParticles3D
var _flash: MeshInstance3D
var _bar: Node3D
var _bar_fill: MeshInstance3D
var _time: float = 0.0
var _collapse_time: float = -1.0
var _smoke_left: float = 0.0
var _hit: float = 0.0
var _fade: float = 0.0
var _burst_fired: bool = false
var _fallen_fragment: int = 0
## Energy leaking from the cracked heart (critical state): fast, irregular sparks upwards.
var _leak: GPUParticles3D
## Critical state: the inner ring has slipped and hangs tilted; one satellite sags (unstable).
var _ring_slipped: bool = false
var _sag: float = 0.0

func setup(definition: Dictionary, facing: Vector2) -> void:
	building_id = str(definition.id)
	team = int(definition.team)
	name = building_id
	seed_value = 3.0 + team * 5.0
	if _scene == null:
		_scene = load(SCENE_PATH)
	var model: Node3D = _scene.instantiate()
	model.name = "Model"
	add_child(model)
	model.rotation.y = atan2(facing.x, facing.y)
	for child: Node in model.get_children():
		_parts[str(child.name)] = child
		_rest[str(child.name)] = (child as Node3D).transform
	_instances = Materials.dress(model)
	Materials.apply_team(_instances, team, seed_value)
	crystal = _parts.get("Crystal")
	crown = _parts.get("Crown")
	crest = _parts.get("Crest_A" if team == 0 else "Crest_B")
	(_parts["Crest_B" if team == 0 else "Crest_A"] as Node3D).visible = false
	for index: int in range(6):
		if _parts.has("Satellite_%d" % index):
			satellites.append(_parts["Satellite_%d" % index])
		if _parts.has("Fragment_%d" % index):
			fragments.append(_parts["Fragment_%d" % index])
	for key: String in ["Ring_Outer", "Ring_Inner"]:
		rings.append(_parts[key])
	for index: int in range(4):
		blades.append(_parts["Blade_%d" % index])
	for key: String in _parts:
		var list: Array = _collect(_parts[key])
		if key == "Crystal" or key.begins_with("Satellite") or key.begins_with("Fragment"):
			_crystals.append_array(list)
		elif key.begins_with("Banner"):
			_cloth.append_array(list)
		elif key.begins_with("Ruin"):
			_ruin.append_array(list)
		else:
			_structure.append_array(list)
	Materials.apply_rune_tint(_structure, team)
	# The glowing heart, satellites, fragments and the banners cast no sun shadow.
	for instance: GeometryInstance3D in _crystals + _cloth:
		instance.cast_shadow = GeometryInstance3D.SHADOW_CASTING_SETTING_OFF
	Materials.set_param(_structure, "crack_glow", 0.0)
	(_parts["Ruin_Crystal"] as Node3D).visible = false
	(_parts["Ruin_Rubble"] as Node3D).visible = false
	light = OmniLight3D.new()
	light.name = "HeartLight"
	light.position = Vector3(0, CRYSTAL_Y, 0)
	light.light_color = Materials.team_color(team, "light")
	light.omni_range = 13.0
	light.omni_attenuation = 1.2
	light.light_energy = 2.2
	add_child(light)
	var color: Color = Materials.team_color(team, "crystal")
	_motes = Fx.motes(color, 22, 2.4, 4.0)
	_motes.position = Vector3(0, 2.4, 0)
	_motes.emitting = true
	add_child(_motes)
	_sparks = Fx.sparks(Materials.team_color(team, "light"), 26, 2.1, 3.0)
	_sparks.position = Vector3(0, 3.2, 0)
	add_child(_sparks)
	_smoke = Fx.smoke(22, 1.4, .15, 2.4, 4.5)
	_smoke.position = Vector3(0, 2.2, 0)
	add_child(_smoke)
	_leak = Fx.leak(color, 34, .9)
	_leak.position = Vector3(0, CRYSTAL_Y - .6, 0)
	add_child(_leak)
	_dust = Fx.dust_burst(70, 2.6, 2.6)
	add_child(_dust)
	_burst = Fx.shard_burst(color, 90, 8.0)
	add_child(_burst)
	_flash = Fx.flash_mesh(Color(color.r * 2.0, color.g * 2.0, color.b * 2.0, 1.0), 9.0)
	_flash.position = Vector3(0, CRYSTAL_Y, 0)
	_flash.visible = false
	add_child(_flash)
	_build_bar(11.2)
	Materials.set_param(_instances, "fade_floor", global_position.y + FADE_FLOOR)

func _collect(node: Node) -> Array:
	var result: Array = []
	if node is GeometryInstance3D:
		result.append(node)
	for child: Node in node.get_children():
		result.append_array(_collect(child))
	return result

func _param(group: Array, group_key: String, parameter: String, value: float, epsilon: float = .01) -> void:
	var key: String = group_key + ":" + parameter
	if _sent.has(key) and absf(float(_sent[key]) - value) < epsilon:
		return
	_sent[key] = value
	Materials.set_param(group, parameter, value)

func _build_bar(height: float) -> void:
	_bar = Node3D.new()
	_bar.name = "HealthBar"
	_bar.position.y = height
	add_child(_bar)
	var width: float = 3.4
	var back := MeshInstance3D.new()
	var quad := QuadMesh.new()
	quad.size = Vector2(width + .1, .26)
	back.mesh = quad
	var back_material := StandardMaterial3D.new()
	back_material.shading_mode = BaseMaterial3D.SHADING_MODE_UNSHADED
	back_material.albedo_color = Color(.03, .03, .05, .78)
	back_material.transparency = BaseMaterial3D.TRANSPARENCY_ALPHA
	back_material.billboard_mode = BaseMaterial3D.BILLBOARD_ENABLED
	back_material.no_depth_test = true
	back.material_override = back_material
	back.cast_shadow = GeometryInstance3D.SHADOW_CASTING_SETTING_OFF
	_bar.add_child(back)
	_bar_fill = MeshInstance3D.new()
	var fill := QuadMesh.new()
	fill.size = Vector2(width, .17)
	fill.center_offset = Vector3(width * .5, 0, 0)
	_bar_fill.mesh = fill
	var fill_material := StandardMaterial3D.new()
	fill_material.shading_mode = BaseMaterial3D.SHADING_MODE_UNSHADED
	fill_material.albedo_color = Materials.team_color(team, "light").lightened(.15)
	fill_material.billboard_mode = BaseMaterial3D.BILLBOARD_ENABLED
	fill_material.billboard_keep_scale = true
	fill_material.no_depth_test = true
	fill_material.render_priority = 1
	_bar_fill.material_override = fill_material
	_bar_fill.position.x = -width * .5
	_bar_fill.cast_shadow = GeometryInstance3D.SHADOW_CASTING_SETTING_OFF
	_bar.add_child(_bar_fill)
	_bar.visible = false

## Height of the dais or plaza surface above the plateau at a local ground distance.
static func surface_lift(distance: float) -> float:
	var lift: float = 0.0
	for step: Array in DAIS_STEPS:
		if distance < float(step[0]):
			lift = float(step[1])
	return lift

func is_standing() -> bool:
	return state != State.COLLAPSING and state != State.FALLEN

## World box of the part that can hide figures (above the fade floor); empty once fallen.
func occluder_box() -> AABB:
	if not is_standing():
		return AABB()
	return AABB(global_position + Vector3(-OCCLUDER_RADIUS, FADE_FLOOR, -OCCLUDER_RADIUS),
		Vector3(OCCLUDER_RADIUS * 2.0, TOP - FADE_FLOOR, OCCLUDER_RADIUS * 2.0))

func current_fade() -> float:
	return _fade

## 0..1 energy of the heart for the floor veins (dims with damage, gone when fallen).
func vein_energy() -> float:
	return {State.STABLE: 1.0, State.UNSTABLE: .75, State.CRITICAL: .5}.get(state, 0.0) * (1.0 + _hit * .8)

func vein_flicker() -> float:
	return {State.STABLE: 0.0, State.UNSTABLE: .25, State.CRITICAL: .7}.get(state, 1.0)

func set_health(value: float, max_value: float, animate: bool = true) -> void:
	var previous: float = fraction
	fraction = clampf(value / maxf(1.0, max_value), 0.0, 1.0)
	if fraction < previous - .0003 and value > 0.0:
		_hit = 1.0
	var next: int = State.STABLE
	if value <= 0.0:
		if state == State.COLLAPSING or state == State.FALLEN:
			next = state
		else:
			next = State.COLLAPSING if animate else State.FALLEN
	elif fraction < CRITICAL_BELOW:
		next = State.CRITICAL
	elif fraction < UNSTABLE_BELOW:
		next = State.UNSTABLE
	if next != state:
		_enter(next)
	_bar.visible = value > 0.0 and fraction < .999
	_bar_fill.scale.x = maxf(.001, fraction)

func _enter(next: int) -> void:
	var from: int = state
	state = next
	var critical: bool = next == State.CRITICAL
	_sparks.emitting = next == State.UNSTABLE or critical
	_sparks.amount_ratio = .55 if next == State.UNSTABLE else 1.0
	_smoke.emitting = critical
	_leak.emitting = critical
	_ring_slipped = critical
	_sag = {State.UNSTABLE: .6, State.CRITICAL: 1.0}.get(next, 0.0)
	_motes.emitting = next in [State.STABLE, State.UNSTABLE, State.CRITICAL]
	_motes.amount_ratio = {State.STABLE: .6, State.UNSTABLE: .8, State.CRITICAL: 1.0}.get(next, 0.0)
	var damage: float = {State.STABLE: 0.0, State.UNSTABLE: .45, State.CRITICAL: .85}.get(next, .9)
	_param(_structure, "structure", "damage", damage)
	_param(_structure, "structure", "crack_glow", {State.UNSTABLE: .8, State.CRITICAL: 1.5}.get(next, 0.0))
	_param(_structure, "structure", "scorch", {State.STABLE: 0.0, State.UNSTABLE: .2, State.CRITICAL: .45}.get(next, .75))
	_param(_cloth, "cloth", "tatter", {State.STABLE: 0.0, State.UNSTABLE: .3, State.CRITICAL: .6}.get(next, .85))
	match next:
		State.CRITICAL:
			# Two blades have come loose (one leans far out), two fragments lie on the dais.
			for spec: Array in [[0, -.3, -.1], [2, .14, -.04]]:
				var blade: Node3D = blades[int(spec[0])]
				var axis: Vector3 = _tangent(int(spec[0]))
				var rest_blade: Transform3D = _rest[str(blade.name)]
				blade.transform = Transform3D(Basis(axis, float(spec[1])) * rest_blade.basis, rest_blade.origin + Vector3(0, float(spec[2]), 0))
			_fallen_fragment = 2
		State.COLLAPSING:
			_collapse_time = 0.0
			_burst_fired = false
		State.FALLEN:
			_collapse_time = -1.0
			_pose_fallen(1.0)
			_leak.emitting = false
			_smoke.emitting = from == State.COLLAPSING
			_smoke.amount_ratio = 1.0
			_smoke_left = 25.0 if from == State.COLLAPSING else 0.0
			light.visible = false
			_bar.visible = false
			Materials.set_param(_ruin, "energy", .16)
			Materials.set_param(_ruin, "flicker", .7)
			Materials.set_param(_ruin, "fracture", .8)
			Materials.set_param(_ruin, "damage", .7)
			_param(_structure, "structure", "energy", .04)
			_param(_structure, "structure", "flicker", 0.0)

func _tangent(index: int) -> Vector3:
	var a: float = BLADE_ANGLES[index]
	return Vector3(-sin(a), 0, cos(a))

func process_view(delta: float, _sim_delta: float) -> void:
	_time += delta
	_hit = maxf(0.0, _hit - delta * 2.5)
	var calm: float = {State.STABLE: 1.0, State.UNSTABLE: .85, State.CRITICAL: .7}.get(state, 0.0)
	var unrest: float = {State.STABLE: 0.0, State.UNSTABLE: .35, State.CRITICAL: 1.0}.get(state, 0.0)
	if is_standing():
		var jitter: float = sin(_time * 21.0) * sin(_time * 7.7) * .02 * unrest
		crystal.position = (_rest["Crystal"] as Transform3D).origin + Vector3(jitter, sin(_time * 1.1) * .07 * calm, 0)
		crystal.rotation.y += delta * (.18 + unrest * .25)
		for index: int in range(satellites.size()):
			var a: float = _time * (.42 + unrest * .2) + TAU * index / satellites.size()
			var r: float = 1.25 + .1 * sin(_time * .9 + index)
			var y: float = CRYSTAL_Y - 1.1 + .35 * sin(_time * .7 + index * 1.3)
			if index == 0 and _sag > 0.0:
				# One satellite has lost its hold: it sags and trembles.
				y -= 1.1 * _sag
				r += .35 * _sag + sin(_time * 13.0) * .03 * _sag
			satellites[index].position = Vector3(cos(a) * r, y, sin(a) * r)
			satellites[index].rotation.y = -a
		for index: int in range(fragments.size()):
			if index < _fallen_fragment:
				fragments[index].position = _fragment_rest(index)
				continue
			var rest: Vector3 = (_rest[str(fragments[index].name)] as Transform3D).origin
			var angle: float = atan2(rest.z, rest.x) + _time * .12
			var radius: float = Vector2(rest.x, rest.z).length()
			fragments[index].position = Vector3(cos(angle) * radius, rest.y + sin(_time * .8 + index) * .18, sin(angle) * radius)
			fragments[index].rotation.y += delta * .5
		var wobble: float = unrest * .08
		rings[0].rotation = Vector3(sin(_time * .6) * wobble, _time * .32, sin(_time * .9) * wobble)
		if _ring_slipped:
			# The inner ring has slipped from its bearing: tilted, grinding round in jerks.
			var jerk: float = floorf(_time * 1.5) * .35 + smoothstep(0.0, .25, fmod(_time * 1.5, 1.0)) * .35
			rings[1].rotation = Vector3(.5 + sin(_time * 2.3) * .03, -jerk, .22)
		else:
			rings[1].rotation = Vector3(sin(_time * .8 + 1.0) * wobble * 1.6, -_time * .46, cos(_time * .7) * wobble * 1.6)
		var flicker: float = {State.STABLE: 0.0, State.UNSTABLE: .25, State.CRITICAL: .85}.get(state, .9)
		_param(_crystals, "crystal", "energy", calm * (1.0 + _hit * 1.4), .02)
		_param(_crystals, "crystal", "flicker", flicker)
		_param(_crystals, "crystal", "fracture", unrest * .8)
		_param(_structure, "structure", "energy", .45 + calm * .55 + _hit * .5, .02)
		_param(_structure, "structure", "flicker", flicker * .8)
		var pulse: float = 1.0
		if flicker > 0.0:
			pulse = lerpf(1.0, .5 + .5 * absf(sin(_time * 17.0 + seed_value) * sin(_time * 5.3)), flicker)
		light.light_energy = (1.0 + calm * 1.3) * pulse * (1.0 + _hit * .8)
	elif state == State.COLLAPSING:
		_collapse_step(delta)
	elif state == State.FALLEN and _smoke_left > 0.0:
		_smoke_left -= delta
		if _smoke_left <= 0.0:
			_smoke.emitting = false
	_fade = move_toward(_fade, fade_target, delta * 3.0)
	_param(_instances, "all", "fade", _fade, .02)

func _fragment_rest(index: int) -> Vector3:
	var rest: Vector3 = (_rest[str(fragments[index].name)] as Transform3D).origin
	var flat := Vector2(rest.x, rest.z).normalized() * 2.95
	return Vector3(flat.x, .32, flat.y)

## Collapse (2.8 s): the heart overloads, implodes and bursts; the blades crumble into the
## dust, rings and crown fall onto the pedestal, fragments drop; the ruin remains.
func _collapse_step(delta: float) -> void:
	_collapse_time += delta
	var t: float = _collapse_time
	var overload: float = smoothstep(0.0, .5, t) * (1.0 - smoothstep(.55, .75, t))
	if crystal.visible:
		crystal.scale = Vector3.ONE * maxf(.05, 1.0 + overload * .14 - smoothstep(.5, .72, t) * .95)
		crystal.rotation.y += delta * (1.0 + overload * 6.0)
		Materials.set_param(_crystals, "energy", 1.0 + overload * 3.5)
		Materials.set_param(_crystals, "flicker", 1.0)
	light.light_energy = 2.2 + overload * 7.0 if t < .8 else maxf(0.0, 9.0 * (1.0 - (t - .8) / .9))
	for index: int in range(rings.size()):
		rings[index].rotation.y += delta * (2.0 + overload * 8.0) * (1.0 if index == 0 else -1.0)
	if t >= .7 and not _burst_fired:
		_burst_fired = true
		Fx.fire(_burst, crystal.global_position)
		Fx.fire(_dust, global_position + Vector3(0, .4, 0))
		crystal.visible = false
		for satellite: Node3D in satellites:
			satellite.visible = false
		(_parts["Ruin_Crystal"] as Node3D).visible = true
		(_parts["Ruin_Rubble"] as Node3D).visible = true
		_flash.visible = true
		_smoke.emitting = true
	if _flash.visible:
		var k: float = clampf((t - .7) / .55, 0.0, 1.0)
		_flash.scale = Vector3.ONE * lerpf(.4, 1.6, k)
		_flash.transparency = k
		if k >= 1.0:
			_flash.visible = false
	if t >= .7:
		_pose_fallen(smoothstep(.7, 2.2, t))
	if t >= COLLAPSE_SECONDS:
		_enter(State.FALLEN)

## Interpolates the falling parts from where they stand to their resting place (k = 0..1).
func _pose_fallen(k: float) -> void:
	var fall: float = k * k
	for index: int in range(blades.size()):
		var blade: Node3D = blades[index]
		var rest: Transform3D = _rest[str(blade.name)]
		var axis: Vector3 = _tangent(index)
		var out := Vector3(cos(BLADE_ANGLES[index]), 0, sin(BLADE_ANGLES[index]))
		blade.transform = Transform3D(Basis(axis, -.45 * fall) * rest.basis, rest.origin + out * .8 * fall + Vector3(0, -2.6 * fall, 0))
		blade.scale = Vector3.ONE * lerpf(1.0, .02, smoothstep(.45, .9, k))
		blade.visible = k < .9
	var landings: Array = [[Vector3(.25, 1.42, -.1), Vector3(.34, 0, .12)], [Vector3(-.3, 1.5, .15), Vector3(-.28, 0, -.42)]]
	for index: int in range(rings.size()):
		var rest: Transform3D = _rest[str(rings[index].name)]
		var land: Array = landings[index]
		rings[index].position = rest.origin.lerp(land[0], fall)
		rings[index].rotation = (rings[index].rotation as Vector3).lerp(land[1], k)
	for node: Node3D in [crown, crest]:
		var rest: Transform3D = _rest[str(node.name)]
		node.position = rest.origin.lerp(Vector3(.2, 1.62, .1), fall)
		node.rotation = Vector3(.45, .3, .22) * k
	for index: int in range(fragments.size()):
		var start: Vector3 = (_rest[str(fragments[index].name)] as Transform3D).origin
		fragments[index].position = start.lerp(_fragment_rest(index), fall)
		fragments[index].rotation = Vector3(1.2, float(index), .4) * k
	if k >= 1.0:
		crystal.visible = false
		for satellite: Node3D in satellites:
			satellite.visible = false
		(_parts["Ruin_Crystal"] as Node3D).visible = true
		(_parts["Ruin_Rubble"] as Node3D).visible = true
		Materials.set_param(_crystals, "energy", .12)
		Materials.set_param(_crystals, "flicker", .8)