extends Node3D
## Visual twin of one LuneUnit. Reads the authoritative state and drives the existing
## figure animations from real combat events; it never writes back into the simulation.

const TEAM_COLORS: Array[Color] = [Color("5aa8ff"), Color("ff6a55"), Color("b37cff")]
const HERO_GOLD := Color("f2c96b")
const Materials = preload("res://scripts/luneraria/view/lune_materials.gd")
## G2: every boss unit (grotto and deployed) shows the Schlundkrone; its veins and crystals
## take the colour of the team it fights for.
const BOSS_MODEL := "schlundkrone"

var unit: LuneUnit
## Ground the figure stands on (lane decks, terrain, grotto terrace); flat without it.
var terrain: LuneTerrain
## Optional world height (adds plaza and dais steps); preferred over the bare terrain.
var ground: Callable
var model: Node3D
var skeletal: bool = false
var _fill: MeshInstance3D
var _bars: Node3D
var _ring: MeshInstance3D
var _last_attack: int = 0
var _last_ability: int = 0
var _attack_flash: float = 0.0
var _ability_flash: float = 0.0
var _time: float = 0.0
var _last_visual: Vector3
var _height: float = 1.6
## Boss look (G2): dressed LN_* surfaces, vein energy that follows sleep, fight and death.
var _boss_surfaces: Array[GeometryInstance3D] = []
var _tag: Label3D
var _boss_energy: float = 1.0
var _sent_energy: float = -1.0
var _sent_flash: float = -1.0

static func _flat(color: Color, energy: float = 0.0) -> StandardMaterial3D:
	var material := StandardMaterial3D.new()
	material.shading_mode = BaseMaterial3D.SHADING_MODE_UNSHADED
	material.albedo_color = color
	if energy > 0.0:
		material.emission_enabled = true
		material.emission = color
		material.emission_energy_multiplier = energy
	return material

func bind(source: LuneUnit) -> void:
	unit = source
	name = "Unit_%d" % unit.id
	var id: String = str(unit.def.get("id", ""))
	if unit.kind == "boss" and AssetLibrary.has_model(BOSS_MODEL):
		id = BOSS_MODEL
	model = AssetLibrary.instantiate_fighter(id)
	if model == null:
		model = EnemyVisualsFallback.make(TEAM_COLORS[unit.team])
	add_child(model)
	if id == BOSS_MODEL:
		_boss_surfaces = Materials.dress(model)
		for surface: GeometryInstance3D in _boss_surfaces:
			surface.set_instance_shader_parameter("tint", Materials.team_color(unit.team, "crystal"))
			surface.set_instance_shader_parameter("seed", 1.7 + unit.team)
		_boss_energy = .45 if unit.dormant else 1.0
	skeletal = model.has_method("update_combat")
	if model.has_method("get_aabb"):
		_height = maxf(1.0, model.get_aabb().end.y)
	var scale_factor: float = float(unit.def.get("view_scale", 1.0))
	model.scale = Vector3.ONE * scale_factor
	_height *= scale_factor
	_ring = MeshInstance3D.new()
	var torus := TorusMesh.new()
	torus.inner_radius = .42 * scale_factor
	torus.outer_radius = .52 * scale_factor
	torus.rings = 20
	torus.ring_segments = 4
	_ring.mesh = torus
	var ring_color: Color = HERO_GOLD if unit.kind == "hero" else TEAM_COLORS[unit.team]
	_ring.material_override = _flat(ring_color, 2.2 if unit.kind in ["hero", "boss", "champion"] else (1.4 if unit.kind != "monster" else .6))
	_ring.scale = Vector3(1, .25, 1)
	_ring.position.y = .05
	_ring.cast_shadow = GeometryInstance3D.SHADOW_CASTING_SETTING_OFF
	add_child(_ring)
	_bars = Node3D.new()
	_bars.position.y = _height + .25
	add_child(_bars)
	var back := MeshInstance3D.new()
	var quad := QuadMesh.new()
	quad.size = Vector2(.9, .1)
	back.mesh = quad
	var back_material := _flat(Color(0, 0, 0, .7))
	back_material.billboard_mode = BaseMaterial3D.BILLBOARD_ENABLED
	back_material.transparency = BaseMaterial3D.TRANSPARENCY_ALPHA
	back_material.no_depth_test = true
	back.material_override = back_material
	back.cast_shadow = GeometryInstance3D.SHADOW_CASTING_SETTING_OFF
	_bars.add_child(back)
	_fill = MeshInstance3D.new()
	var fill_quad := QuadMesh.new()
	fill_quad.size = Vector2(.86, .07)
	fill_quad.center_offset = Vector3(.43, 0, 0)
	_fill.mesh = fill_quad
	var fill_material := _flat(TEAM_COLORS[unit.team].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
	_fill.material_override = fill_material
	_fill.position = Vector3(-.43, 0, 0)
	_fill.cast_shadow = GeometryInstance3D.SHADOW_CASTING_SETTING_OFF
	_bars.add_child(_fill)
	if unit.kind in ["hero", "champion", "boss"]:
		# Named units carry a readable tag: heroes with level, champions with role, the boss.
		var tag := Label3D.new()
		tag.billboard = BaseMaterial3D.BILLBOARD_ENABLED
		tag.no_depth_test = true
		tag.fixed_size = true
		# Fixed screen size under the perspective game camera (about 18 px at 1080p).
		tag.pixel_size = .00034
		tag.font_size = 30
		tag.outline_size = 10
		tag.modulate = HERO_GOLD if unit.kind == "hero" else TEAM_COLORS[unit.team].lightened(.3)
		tag.position.y = _height + .55
		var title: String = str(unit.def.get("display_name", ""))
		if unit.kind == "hero":
			title = "%s · Stufe %d" % [title, int(unit.def.get("level", 1))]
		tag.text = title
		add_child(tag)
		_tag = tag
	_last_attack = unit.attack_serial
	_last_ability = unit.ability_serial
	position = Vector3(unit.position.x, _ground(unit.position), unit.position.y)
	rotation.y = unit.facing
	_last_visual = position

func sync(alpha: float, delta: float) -> void:
	if unit == null:
		return
	_time += delta
	var at: Vector2 = unit.previous_position.lerp(unit.position, clampf(alpha, 0.0, 1.0))
	position = Vector3(at.x, _ground(at), at.y)
	rotation.y = lerp_angle(rotation.y, unit.facing, minf(1.0, delta * 12.0))
	var moved: float = Vector2(position.x - _last_visual.x, position.z - _last_visual.z).length()
	_last_visual = position
	if unit.attack_serial != _last_attack:
		_last_attack = unit.attack_serial
		_attack_flash = .28
	if unit.ability_serial != _last_ability:
		_last_ability = unit.ability_serial
		_ability_flash = .5
	_attack_flash = maxf(0.0, _attack_flash - delta)
	_ability_flash = maxf(0.0, _ability_flash - delta)
	if skeletal:
		model.rotation.y = 0.0
		model.update_combat(delta, moved, unit.in_range and unit.alive, unit.attack_progress, unit.hit_count, _ability_flash, unit.hit_flash, unit.alive)
	elif model.has_method("pose"):
		model.pose(_time + float(unit.id % 17) * .23, moved > .002, _attack_flash, _ability_flash, unit.hit_flash)
	if not _boss_surfaces.is_empty():
		_sync_boss(delta)
	var fraction: float = clampf(unit.hp / maxf(1.0, unit.max_hp), 0.0, 1.0)
	_fill.scale.x = maxf(.001, fraction)
	_bars.visible = unit.alive and fraction < .999
	_ring.visible = unit.alive
	if _tag != null:
		# Fallen skeletal figures stay in their death pose, but without their name.
		_tag.visible = unit.alive
	# Rigid figures have no death clip; skeletal ones stay down in their death pose.
	if not skeletal:
		visible = unit.alive

## Veins sleep while the grotto boss is dormant, burn while it fights, flash on hits and go
## out over its death clip.
func _sync_boss(delta: float) -> void:
	var goal: float = 0.0 if not unit.alive else (.45 if unit.dormant else 1.0)
	_boss_energy = move_toward(_boss_energy, goal, delta * (.6 if not unit.alive else 1.5))
	var flash: float = clampf(unit.hit_flash * 2.2, 0.0, .45) if unit.alive else 0.0
	if absf(_boss_energy - _sent_energy) > .01:
		_sent_energy = _boss_energy
		for surface: GeometryInstance3D in _boss_surfaces:
			surface.set_instance_shader_parameter("energy", _boss_energy)
	if absf(flash - _sent_flash) > .02:
		_sent_flash = flash
		for surface: GeometryInstance3D in _boss_surfaces:
			surface.set_instance_shader_parameter("damage", flash)

## Where tower bolts and effects hit this figure (upper body, not the feet).
func aim_point() -> Vector3:
	return global_position + Vector3(0, _height * .55, 0)

## Relative ground footprint for lock-on markers (bigger figures get bigger rings).
func footprint() -> float:
	return clampf(float(unit.def.get("view_scale", 1.0)) if unit != null else 1.0, .8, 2.2)

func _ground(at: Vector2) -> float:
	if ground.is_valid():
		return float(ground.call(at)) + .03
	return terrain.walk_height(at) + .03 if terrain != null else 0.0

class EnemyVisualsFallback:
	static func make(color: Color) -> Node3D:
		var body := MeshInstance3D.new()
		var capsule := CapsuleMesh.new()
		capsule.radius = .35
		capsule.height = 1.4
		body.mesh = capsule
		body.position.y = .7
		var material := StandardMaterial3D.new()
		material.albedo_color = color
		body.material_override = material
		var root := Node3D.new()
		root.add_child(body)
		return root