extends Sprite3D

const ICON_SIZE := 10
const ICON_MARGIN := 1
const BORDER_W := 1

@onready var viewport: SubViewport = $SubViewport
@onready var health_bar: ProgressBar = $SubViewport/HealthBar
@onready var border: ColorRect = $SubViewport/Border
@onready var parent_node: Node = get_parent()

var shield_bar: ProgressBar = null
var style_normal: StyleBoxFlat
var style_aggro: StyleBoxFlat
var effect_container: HBoxContainer = null
var base_viewport_height: int = 0

func _ready() -> void:
  shield_bar = $SubViewport.get_node_or_null("ShieldBar")
  border.visible = false
  style_normal = health_bar.get_theme_stylebox("fill").duplicate()
  style_aggro = style_normal.duplicate()
  style_aggro.bg_color = Color(0.2, 0.4, 0.9, 1)
  base_viewport_height = viewport.size.y
  _create_effect_container()
  texture = viewport.get_texture()
  EventBus.target_changed.connect(_on_target_changed)
  EventBus.health_changed.connect(_on_health_changed)
  EventBus.shield_changed.connect(_on_shield_changed)
  EventBus.effect_applied.connect(_on_effect_applied)
  EventBus.effect_expired.connect(_on_effect_expired)
  _init_bars()

func _create_effect_container() -> void:
  effect_container = HBoxContainer.new()
  effect_container.name = "EffectContainer"
  var y_pos: float = 0.0
  if shield_bar and shield_bar.visible:
    y_pos = shield_bar.offset_bottom + 2
  else:
    y_pos = health_bar.offset_bottom + 2
  effect_container.position = Vector2(2, y_pos)
  effect_container.add_theme_constant_override("separation", ICON_MARGIN)
  viewport.add_child(effect_container)

func _init_bars() -> void:
  var max_health: Variant = Stats.get_stat(parent_node, "max_health")
  if max_health != null:
    health_bar.max_value = max_health
    health_bar.value = Stats.get_stat(parent_node, "health")
  var max_shield: Variant = Stats.get_stat(parent_node, "max_shield")
  if shield_bar:
    if max_shield != null and max_shield > 0:
      shield_bar.max_value = max_shield
      shield_bar.value = Stats.get_stat(parent_node, "shield")
    else:
      shield_bar.visible = false
      effect_container.position.y = health_bar.offset_bottom + 2

func _process(_delta: float) -> void:
  var player: Node = get_tree().get_first_node_in_group("player")
  if player and "target" in parent_node and parent_node.target == player:
    health_bar.add_theme_stylebox_override("fill", style_aggro)
  else:
    health_bar.add_theme_stylebox_override("fill", style_normal)

func _on_health_changed(entity: Node, current: float, max_val: float) -> void:
  if entity != parent_node:
    return
  health_bar.max_value = max_val
  health_bar.value = current

func _on_shield_changed(entity: Node, current: float, max_val: float) -> void:
  if entity != parent_node or shield_bar == null:
    return
  shield_bar.max_value = max_val
  shield_bar.value = current

func _on_target_changed(_player: Node, target: Node) -> void:
  border.visible = (target == get_parent())

func _on_effect_applied(target: Node, effect: Effect) -> void:
  if target != parent_node:
    return
  _add_effect_icon(effect)

func _on_effect_expired(target: Node, effect: Effect) -> void:
  if target != parent_node:
    return
  _remove_effect_icon(effect)

func _add_effect_icon(effect: Effect) -> void:
  var panel := _create_icon_panel(effect)
  var insert_idx: int = _get_sorted_index(effect.type)
  effect_container.add_child(panel)
  effect_container.move_child(panel, insert_idx)
  _resize_viewport()

func _remove_effect_icon(effect: Effect) -> void:
  for child in effect_container.get_children():
    if child.has_meta("effect_type") and child.has_meta("effect_name"):
      if child.get_meta("effect_type") == effect.type and child.get_meta("effect_name") == effect.effect_name:
        child.queue_free()
        _resize_viewport.call_deferred()
        return

func _get_sorted_index(type: int) -> int:
  var idx := 0
  for child in effect_container.get_children():
    if not child.has_meta("effect_type"):
      continue
    var child_type: int = child.get_meta("effect_type")
    if child_type <= type:
      idx += 1
    else:
      break
  return idx

func _create_icon_panel(effect: Effect) -> PanelContainer:
  var panel := PanelContainer.new()
  var style := StyleBoxFlat.new()
  match effect.type:
    Effect.Type.AURA:
      style.bg_color = Color(0.15, 0.15, 0.3, 1)
      style.border_color = Color(0.3, 0.5, 1.0, 1)
    Effect.Type.BUFF:
      style.bg_color = Color(0.15, 0.3, 0.15, 1)
      style.border_color = Color(0.3, 1.0, 0.3, 1)
    Effect.Type.DEBUFF:
      style.bg_color = Color(0.3, 0.15, 0.15, 1)
      style.border_color = Color(1.0, 0.3, 0.3, 1)
  style.set_border_width_all(BORDER_W)
  style.set_content_margin_all(0)
  panel.add_theme_stylebox_override("panel", style)
  var label := Label.new()
  label.text = effect.effect_name.left(1)
  label.horizontal_alignment = HORIZONTAL_ALIGNMENT_CENTER
  label.vertical_alignment = VERTICAL_ALIGNMENT_CENTER
  label.add_theme_font_size_override("font_size", 7)
  label.add_theme_color_override("font_color", Color.WHITE)
  label.custom_minimum_size = Vector2(ICON_SIZE, ICON_SIZE)
  panel.add_child(label)
  panel.custom_minimum_size = Vector2(ICON_SIZE + 2, ICON_SIZE + 2)
  panel.set_meta("effect_type", effect.type)
  panel.set_meta("effect_name", effect.effect_name)
  return panel

func _resize_viewport() -> void:
  var icon_count := 0
  for child in effect_container.get_children():
    if not child.is_queued_for_deletion():
      icon_count += 1
  if icon_count > 0:
    var needed: int = int(effect_container.position.y) + ICON_SIZE + 4
    viewport.size.y = max(base_viewport_height, needed)
    border.offset_bottom = viewport.size.y
  else:
    viewport.size.y = base_viewport_height
    border.offset_bottom = base_viewport_height