class_name SystemDock
extends Control
## The slide-in system dock (mock 2a): a gold handle toggles a column of screen
## buttons in/out. §2: state (owns the open toggle via ShellState). The buttons
## are the routing seam — they emit screen_requested; the screens they open land
## in later milestones, so the signal is currently a no-op for the shell.

signal screen_requested(id: StringName)

const SCREENS := [
	[&"inventory", "Inventory", "I"],
	[&"character", "Character", "C"],
	[&"quest_log", "Quest Log", "J"],
	[&"spellbook", "Spellbook", "K"],
	[&"world_map", "World Map", "M"],
	[&"party", "Party", "P"],
]
const SLIDE_SECONDS := 0.32
const HIDDEN_SHIFT := 230.0

var _screen_buttons: Dictionary = {}
var _state: ShellState
var _menu: VBoxContainer
var _handle: Button


func _ready() -> void:
	_menu = VBoxContainer.new()
	_menu.add_theme_constant_override("separation", 10)
	add_child(_menu)
	for entry in SCREENS:
		var id: StringName = entry[0]
		var button := Button.new()
		button.text = "%s   %s" % [entry[2], entry[1]]
		button.theme_type_variation = ThemeKeys.DARK_PANEL
		button.pressed.connect(func(): screen_requested.emit(id))
		_menu.add_child(button)
		_screen_buttons[id] = button

	_handle = Button.new()
	_handle.text = "›"
	_handle.theme_type_variation = ThemeKeys.TAB_ACTIVE
	_handle.pressed.connect(_on_handle_pressed)
	add_child(_handle)


func setup(state: ShellState) -> void:
	_state = state
	_apply_open(_state.dock_open)


func _on_handle_pressed() -> void:
	if _state == null:
		return
	_apply_open(_state.toggle_dock())


func _apply_open(open: bool) -> void:
	_handle.text = "›" if open else "‹"
	var target := Vector2.ZERO if open else Vector2(HIDDEN_SHIFT, 0.0)
	var alpha := 1.0 if open else 0.0
	if not is_inside_tree():
		_menu.position = target
		_menu.modulate.a = alpha
		return
	var tween := create_tween().set_parallel(true)
	tween.tween_property(_menu, "position", target, SLIDE_SECONDS)
	tween.tween_property(_menu, "modulate:a", alpha, SLIDE_SECONDS)