class_name RulePanel
extends PopupPanel
## RulePanel - Rule list editor popup (Phase 3c.4).
##
## Shows a list of rules (already filtered by the stage: by source stickman or
## by waypoint), with edit / delete / drag-reorder controls and Add Rule / Clear
## All. Mutations delegate to the stage via signals; reordering emits the new
## order of the *displayed* rules' ids, which the stage maps back onto its
## full `_event_rules` array (preserving un-filtered rules' positions).

const ACTION_REGISTRY := preload("res://scripts/action_registry.gd")
const TRIGGER_REGISTRY := preload("res://scripts/trigger_registry.gd")

signal edit_requested(rule_id: int)
signal delete_requested(rule_id: int)
signal add_requested()
signal clear_requested()
signal reorder_requested(ordered_ids: Array[int])

var _title_label: Label = null
var _list: VBoxContainer = null
var _empty_label: Label = null
var _rows: Array[PanelContainer] = []
var _rules: Array[Dictionary] = []

var _drag_index: int = -1
var _drag_target: int = -1

## Theme font overrides (set via apply_font from sandbox_theme.json). Size 0 = no
## override (engine default); Font null = no override.
var _ui_font: Font = null
var _emoji_font: Font = null
var _base_font_size: int = 0
var _row_font_size: int = 0
var _title_font_size: int = 0
var _title_font: Font = null


func _ready() -> void:
	exclusive = true
	popup_window = true
	_build_ui()


func _unhandled_input(event: InputEvent) -> void:
	if event is InputEventKey and event.pressed and not event.echo:
		if (event as InputEventKey).keycode == KEY_ESCAPE:
			hide()


## Updates the displayed rule list + title without popping up.
func set_rules(rules: Array[Dictionary], title_hint: String) -> void:
	_rules = rules.duplicate(true)
	_title_label.text = title_hint
	refresh()


## Attaches a filtered rule list + a source hint, rebuilds the rows and pops up.
func show_rules(rules: Array[Dictionary], title_hint: String) -> void:
	set_rules(rules, title_hint)
	popup_centered()


func refresh() -> void:
	if _list == null:
		return
	for child: Node in _list.get_children():
		if child != _empty_label:
			child.queue_free()
	_rows.clear()
	_drag_index = -1
	_drag_target = -1
	_empty_label.visible = _rules.is_empty()
	for i: int in _rules.size():
		_rows.append(_make_row(i, _rules[i]))


func _build_ui() -> void:
	title = "Rules"
	var margin := MarginContainer.new()
	margin.add_theme_constant_override("margin_left", 12)
	margin.add_theme_constant_override("margin_right", 12)
	margin.add_theme_constant_override("margin_top", 12)
	margin.add_theme_constant_override("margin_bottom", 12)
	add_child(margin)

	var vbox := VBoxContainer.new()
	vbox.add_theme_constant_override("separation", 8)
	margin.add_child(vbox)

	var title_bar := HBoxContainer.new()
	vbox.add_child(title_bar)
	_title_label = Label.new()
	_title_label.size_flags_horizontal = Control.SIZE_EXPAND_FILL
	_title_label.text = "Source: ?"
	title_bar.add_child(_title_label)
	var close_btn := Button.new()
	close_btn.text = "× Close"
	close_btn.pressed.connect(hide)
	title_bar.add_child(close_btn)

	var scroll := ScrollContainer.new()
	scroll.size_flags_vertical = Control.SIZE_EXPAND_FILL
	scroll.custom_minimum_size = Vector2(0.0, 260.0)
	vbox.add_child(scroll)

	_list = VBoxContainer.new()
	_list.size_flags_horizontal = Control.SIZE_EXPAND_FILL
	_list.add_theme_constant_override("separation", 4)
	scroll.add_child(_list)

	_empty_label = Label.new()
	_empty_label.text = "No rules."
	_empty_label.modulate = Color(1.0, 1.0, 1.0, 0.5)
	_list.add_child(_empty_label)

	var footer := HBoxContainer.new()
	footer.add_theme_constant_override("separation", 8)
	vbox.add_child(footer)
	var add_btn := Button.new()
	add_btn.text = "➕ Add Rule"
	add_btn.pressed.connect(func() -> void: add_requested.emit())
	footer.add_child(add_btn)
	var clear_btn := Button.new()
	clear_btn.text = "🗑 Clear All"
	clear_btn.pressed.connect(func() -> void: clear_requested.emit())
	footer.add_child(clear_btn)

	min_size = Vector2i(520, 360)


func _make_row(index: int, rule: Dictionary) -> PanelContainer:
	var panel := PanelContainer.new()
	panel.add_theme_stylebox_override("panel", _row_style(Color(0.0, 0.0, 0.0, 0.0)))

	var row := HBoxContainer.new()
	row.add_theme_constant_override("separation", 6)
	panel.add_child(row)

	var number := Label.new()
	number.text = str(index + 1)
	row.add_child(number)

	var body := VBoxContainer.new()
	body.size_flags_horizontal = Control.SIZE_EXPAND_FILL
	row.add_child(body)

	body.add_child(_make_label(_trigger_summary(rule)))
	var actions := _action_summaries(rule)
	if actions.is_empty():
		body.add_child(_make_label("→ (no actions)", true))
	else:
		for text: String in actions:
			body.add_child(_make_label(text, true))

	var edit := Button.new()
	edit.text = "✎"
	edit.tooltip_text = "Edit"
	edit.pressed.connect(func() -> void: edit_requested.emit(int(rule.get("id", -1))))
	row.add_child(edit)

	var remove := Button.new()
	remove.text = "✕"
	remove.tooltip_text = "Delete"
	remove.pressed.connect(func() -> void: delete_requested.emit(int(rule.get("id", -1))))
	row.add_child(remove)

	var drag := Button.new()
	drag.text = "≡"
	drag.tooltip_text = "Drag to reorder"
	drag.mouse_default_cursor_shape = Control.CURSOR_MOVE
	drag.gui_input.connect(_on_drag_handle_gui_input.bind(index))
	row.add_child(drag)

	# Parent the row into the list and apply the theme font/size overrides. Without
	# add_child the row never renders and drag-reorder has no geometry to work with.
	_list.add_child(panel)
	_apply_font_recursive(panel, _row_font_size)
	return panel


## Applies theme font/size overrides (mirrors AssetSelector.apply_font). Called by
## the stage after add_child so the panel's UI is already built.
func apply_font(ui_font: Font, emoji_font: Font, sizes: Dictionary) -> void:
	_ui_font = ui_font
	_emoji_font = emoji_font
	_base_font_size = int(sizes.get("rule_panel", 18))
	_row_font_size = int(sizes.get("panel_row", 16))
	_title_font_size = int(sizes.get("panel_title", 18))
	var title_bold := bool(sizes.get("panel_title_bold", true))
	var bold_font: Font = sizes.get("bold_font", null)
	_title_font = bold_font if title_bold and bold_font != null else ui_font
	_apply_font_recursive(self, _base_font_size)
	if _title_label != null:
		_apply_font_to(_title_label, _title_font_size, _title_font)
	if _empty_label != null:
		_apply_font_to(_empty_label, _row_font_size)


func _apply_font_recursive(node: Node, size: int) -> void:
	for child: Node in node.get_children():
		if child is Control:
			_apply_font_to(child as Control, size)
		_apply_font_recursive(child, size)


func _apply_font_to(c: Control, size: int, font: Font = null) -> void:
	if c == null:
		return
	if font != null:
		c.add_theme_font_override("font", font)
	elif _ui_font != null:
		c.add_theme_font_override("font", _ui_font)
	elif _emoji_font != null:
		c.add_theme_font_override("font", _emoji_font)
	if size > 0:
		c.add_theme_font_size_override("font_size", size)


func _make_label(text: String, dim: bool = false) -> Label:
	var lbl := Label.new()
	lbl.text = text
	if dim:
		lbl.modulate = Color(1.0, 1.0, 1.0, 0.7)
	return lbl


func _trigger_summary(rule: Dictionary) -> String:
	var trigger: Dictionary = rule.get("trigger", {})
	var type := String(trigger.get("type", ""))
	return "%s %s %s" % [
		TRIGGER_REGISTRY.icon(type),
		_actor_name(int(trigger.get("source", -1))),
		TRIGGER_REGISTRY.label(type),
	]


func _action_summaries(rule: Dictionary) -> Array[String]:
	var out: Array[String] = []
	for a: Dictionary in rule.get("actions", []):
		out.append("→ %s %s %s" % [
			ACTION_REGISTRY.icon(String(a.get("type", ""))),
			_actor_name(int(a.get("target", -1))),
			ACTION_REGISTRY.summarize(a),
		])
	return out


func _row_style(bg: Color) -> StyleBoxFlat:
	var sb := StyleBoxFlat.new()
	sb.bg_color = bg
	sb.set_corner_radius_all(4)
	sb.content_margin_left = 6.0
	sb.content_margin_right = 6.0
	sb.content_margin_top = 2.0
	sb.content_margin_bottom = 2.0
	return sb


func _on_drag_handle_gui_input(event: InputEvent, index: int) -> void:
	if event is InputEventMouseButton and (event as InputEventMouseButton).button_index == MOUSE_BUTTON_LEFT:
		if (event as InputEventMouseButton).pressed:
			_drag_index = index
			_drag_target = index
			_refresh_drag_highlight()
		else:
			_commit_drag()
	elif event is InputEventMouseMotion and _drag_index >= 0:
		_update_drag_target()


func _update_drag_target() -> void:
	var mouse_y := _list.get_local_mouse_position().y
	var best := _drag_target
	var best_d := INF
	for i: int in _rows.size():
		var row := _rows[i]
		var d := absf((row.position.y + row.size.y * 0.5) - mouse_y)
		if d < best_d:
			best_d = d
			best = i
	if best != _drag_target:
		_drag_target = best
		_refresh_drag_highlight()


func _refresh_drag_highlight() -> void:
	for i: int in _rows.size():
		var bg := Color(0.0, 0.0, 0.0, 0.0)
		if _drag_index >= 0 and i == _drag_target:
			bg = Color(0.15, 0.4, 0.9, 0.4)
		(_rows[i] as PanelContainer).add_theme_stylebox_override("panel", _row_style(bg))


func _commit_drag() -> void:
	var from := _drag_index
	var to := _drag_target
	_drag_index = -1
	_drag_target = -1
	_refresh_drag_highlight()
	if from < 0 or to < 0 or from == to or from >= _rules.size() or to >= _rules.size():
		return
	var moved: Dictionary = _rules[from]
	_rules.remove_at(from)
	_rules.insert(to, moved)
	var ordered: Array[int] = []
	for r: Dictionary in _rules:
		ordered.append(int(r.get("id", -1)))
	refresh()
	reorder_requested.emit(ordered)


func _actor_name(id: int) -> String:
	if id <= 0:
		# -1 is the "no source / no actor" sentinel; instance_from_id(-1) would
		# spam an engine error, so resolve the display name only for real ids.
		return "?"
	var node := instance_from_id(id)
	if node is Node and is_instance_valid(node):
		return String((node as Node).name)
	return "?"