extends Control

## D-057: Entity interaction vertical list — insert-styled, z-layer 6.
## Compact list of 2-4 verb options, anchored to entity position.
## Sprint suppression (D-055): hidden while sprinting.
## Diegetic test: labels disappear when insert is off.
##
## Replaces the single-line interaction_prompt for multi-verb scenarios.
## Public API matches QA test contract (test_interaction_list.gd).

signal verb_selected(kind: String, entity_id: int)

const MAX_VERBS := 4
# Intentionally faster than cursor 150ms — text must be readable quickly
const FADE_IN := 0.12
const FADE_OUT := 0.10
const LABEL_HEIGHT := 22
const LABEL_GAP := 2
const INSERT_FG := Constants.IMPLANT_TEXT_COLOR
const INSERT_DIM := Constants.IMPLANT_TEXT_DIM
const INSERT_BG := Color(0.05, 0.05, 0.08, 0.7)
const ENTITY_OFFSET := Vector2(0, -12)  # nudge above entity sprite center

var _showing: bool = false
var _insert_active: bool = true
var _current_target_id: int = -1
var _entity_world_pos: Vector2 = Vector2.ZERO  # cached world tile position of target
var _verb_items: Array = []  # sorted [{kind, label, priority, available}]
var _selected_index: int = 0
var _active_tween: Tween = null
var _verb_labels: Array[Label] = []
# #537: D-033 relationship color — cached per target, drawn as left-edge accent bar
var _relationship_color: Color = Constants.IMPLANT_TEXT_DIM

var _last_screen_pos: Vector2 = Vector2.ZERO

@onready var _vbox: VBoxContainer = $VBox


func _ready() -> void:
	modulate.a = 0.0
	visible = false
	mouse_filter = Control.MOUSE_FILTER_IGNORE


func _process(_delta: float) -> void:
	if _showing:
		_update_screen_position()
		if position != _last_screen_pos:
			_last_screen_pos = position
			queue_redraw()


func _draw() -> void:
	if not _showing or _verb_labels.is_empty():
		return
	var pad := 6.0
	var bg_rect := Rect2(-pad, -pad, size.x + pad * 2, size.y + pad * 2)
	draw_rect(bg_rect, INSERT_BG)
	draw_rect(bg_rect, Constants.IMPLANT_TEXT_DIM * Color(1, 1, 1, 0.3), false, 1.0)
	# #537: D-033 relationship color accent — 3px left-edge bar signals NPC relationship
	var bar_rect := Rect2(-pad, -pad, 3.0, bg_rect.size.y)
	draw_rect(bar_rect, _relationship_color * Color(1, 1, 1, 0.85))


func update_from_state() -> void:
	# D-055: Sprint stance suppresses interaction list
	if GameState.player_stance == "Sprint":
		_hide()
		return

	# Diegetic toggle — insert off means no overlay data
	if not _insert_active:
		_hide()
		return

	var interactions: Array = GameState.nearby_interactions
	if interactions.is_empty():
		_hide()
		return

	var interaction: Dictionary = interactions[0]
	var entity_id: int = interaction.get("entity_id", -1)
	var verbs: Array = interaction.get("verbs", [])

	if verbs.is_empty():
		_hide()
		return

	# Sort by priority ascending, cap at MAX_VERBS
	var sorted: Array = verbs.duplicate()
	sorted.sort_custom(func(a, b): return a.get("priority", 99) < b.get("priority", 99))
	if sorted.size() > MAX_VERBS:
		sorted = sorted.slice(0, MAX_VERBS)

	_current_target_id = entity_id
	_verb_items = sorted
	_selected_index = 0
	_cache_entity_position()
	_cache_entity_relationship()
	_rebuild_labels()
	_show()


func _rebuild_labels() -> void:
	# Guard: tween callback from previous _hide() may fire after labels already freed
	for lbl in _verb_labels:
		if is_instance_valid(lbl):
			lbl.queue_free()
	_verb_labels.clear()

	for i in range(_verb_items.size()):
		var verb: Dictionary = _verb_items[i]
		var lbl := Label.new()
		lbl.text = " %s " % verb.get("label", "")
		lbl.add_theme_font_size_override("font_size", 14)
		lbl.add_theme_color_override(
			"font_color", INSERT_FG if i == _selected_index else INSERT_DIM
		)
		lbl.horizontal_alignment = HORIZONTAL_ALIGNMENT_LEFT
		lbl.mouse_filter = Control.MOUSE_FILTER_STOP
		lbl.mouse_default_cursor_shape = Control.CURSOR_POINTING_HAND
		var idx := i
		lbl.gui_input.connect(
			func(event: InputEvent):
				if (
					event is InputEventMouseButton
					and event.pressed
					and event.button_index == MOUSE_BUTTON_LEFT
				):
					_select_and_interact(idx)
		)
		lbl.mouse_entered.connect(func(): _hover_index(idx))
		lbl.mouse_exited.connect(func(): _unhover_index(idx))
		_vbox.add_child(lbl)
		_verb_labels.append(lbl)


## Cache the target entity's world tile position from GameState.visible_entities.
func _cache_entity_position() -> void:
	for entity in GameState.visible_entities:
		if entity.get("entity_id") == _current_target_id:
			_entity_world_pos = Vector2(entity.x, entity.y)
			return


## #537: Cache relationship color for the target entity (D-033 palette).
## Falls back to IMPLANT_TEXT_DIM for non-NPC or unknown entities.
func _cache_entity_relationship() -> void:
	for entity in GameState.visible_entities:
		if entity.get("entity_id") == _current_target_id:
			var rel: String = str(entity.get("relationship", "Unknown"))
			_relationship_color = Constants.color_for_relationship(rel)
			return
	_relationship_color = Constants.IMPLANT_TEXT_DIM


## Convert entity world position to screen coords and reposition this Control.
## Runs every frame while showing so the list tracks the entity as the camera moves.
func _update_screen_position() -> void:
	var camera := get_viewport().get_camera_2d()
	if camera == null:
		return
	var viewport_size := get_viewport_rect().size
	var cam_center := camera.get_screen_center_position()
	var zoom: Vector2 = (
		camera.zoom if camera.zoom.length_squared() > 0.01 else Constants.CAMERA_DEFAULT_ZOOM
	)
	var world_px := _entity_world_pos * Constants.TILE_SIZE
	var screen_pos := (world_px - cam_center) * zoom + viewport_size / 2.0
	# Anchor above the entity, centered horizontally
	position = screen_pos + ENTITY_OFFSET * zoom - Vector2(size.x / 2.0, size.y)


func _show() -> void:
	if _showing:
		return
	_showing = true
	visible = true
	if _active_tween and _active_tween.is_valid():
		_active_tween.kill()
	_active_tween = create_tween()
	_active_tween.tween_property(self, "modulate:a", 1.0, FADE_IN)


func _hide() -> void:
	if not _showing:
		return
	_showing = false
	_current_target_id = -1
	_verb_items.clear()
	if _active_tween and _active_tween.is_valid():
		_active_tween.kill()
	_active_tween = create_tween()
	_active_tween.tween_property(self, "modulate:a", 0.0, FADE_OUT)
	# Guard: tween callback from previous _hide() may fire after labels already freed
	_active_tween.tween_callback(
		func():
			visible = false
			for lbl in _verb_labels:
				if is_instance_valid(lbl):
					lbl.queue_free()
			_verb_labels.clear()
	)


# -- Lazy sync for getters (tests may set GameState without calling update) --


func _ensure_synced() -> void:
	if _current_target_id == -1 and not GameState.nearby_interactions.is_empty():
		update_from_state()


# -- Public API (QA test contract) ------------------------------------------


func get_visible_verb_count() -> int:
	_ensure_synced()
	return _verb_items.size()


func hide_list() -> void:
	_hide()


func is_showing() -> bool:
	return _showing


func get_selected_verb() -> String:
	_ensure_synced()
	if _verb_items.is_empty():
		return ""
	return _verb_items[_selected_index].get("kind", "")


func get_interaction_target() -> int:
	_ensure_synced()
	return _current_target_id


func get_verb_labels() -> Array:
	var labels: Array = []
	for verb in _verb_items:
		labels.append(verb.get("label", ""))
	return labels


func _hover_index(idx: int) -> void:
	_selected_index = idx
	_update_label_colors()


func _unhover_index(_idx: int) -> void:
	pass  # keep last hover highlighted


func _select_and_interact(idx: int) -> void:
	if idx < 0 or idx >= _verb_items.size():
		return
	_selected_index = idx
	verb_selected.emit(_verb_items[idx].get("kind", ""), _current_target_id)


func _update_label_colors() -> void:
	for i in range(_verb_labels.size()):
		if is_instance_valid(_verb_labels[i]):
			_verb_labels[i].add_theme_color_override(
				"font_color", INSERT_FG if i == _selected_index else INSERT_DIM
			)


func set_insert_active(active: bool) -> void:
	_insert_active = active
	if not active and _showing:
		_hide()


func get_z_layer() -> int:
	return Constants.CANVAS_INSERT