extends CanvasLayer
## Startmenü: Einzelspieler, Mehrspieler (hosten oder per Code beitreten),
## Lobby und Beenden.

const BOT_NAMES_MAX := 7

var screens: Dictionary = {}
var status_labels: Dictionary = {}
var current := "main"

# Einzelspieler
var solo_bots: NumberRow

# Mehrspieler
var name_edit: LineEdit
var code_edit: LineEdit

# Lobby
var lobby_bots: NumberRow
var code_label: Label
var lobby_list: Label
var start_btn: Button


func _ready() -> void:
	var root := Control.new()
	root.set_anchors_and_offsets_preset(Control.PRESET_FULL_RECT)
	add_child(root)

	var bg := ColorRect.new()
	bg.set_anchors_and_offsets_preset(Control.PRESET_FULL_RECT)
	bg.color = Color(0.05, 0.06, 0.09)
	root.add_child(bg)

	screens["main"] = _screen(root, _build_main())
	screens["single"] = _screen(root, _build_single())
	screens["multi"] = _screen(root, _build_multi())
	screens["join"] = _screen(root, _build_join())
	screens["lobby"] = _screen(root, _build_lobby())

	Net.lobby_changed.connect(_refresh)
	Net.connection_failed.connect(_on_failed)
	Net.server_closed.connect(_on_closed)
	_show("main")


# ------------------------------------------------------------ Aufbau

func _screen(root: Control, content: Control) -> CenterContainer:
	var cc := CenterContainer.new()
	cc.set_anchors_and_offsets_preset(Control.PRESET_FULL_RECT)
	cc.add_child(content)
	root.add_child(cc)
	return cc


func _show(which: String) -> void:
	current = which
	for key: String in screens:
		screens[key].visible = key == which
	_sagen("")
	if which == "lobby":
		_refresh()


## Meldungen gehören auf den Bildschirm, auf dem man gerade steht.
func _sagen(text: String) -> void:
	for key: String in status_labels:
		status_labels[key].text = text if key == current else ""


func _box(width: int) -> VBoxContainer:
	var v := VBoxContainer.new()
	v.custom_minimum_size = Vector2(width, 0)
	v.add_theme_constant_override("separation", 10)
	return v


func _text(t: String, size: int, col := Color.WHITE) -> Label:
	var l := Label.new()
	l.text = t
	l.add_theme_font_size_override("font_size", size)
	l.add_theme_color_override("font_color", col)
	l.horizontal_alignment = HORIZONTAL_ALIGNMENT_CENTER
	return l


func _row(caption: String, ctrl: Control) -> HBoxContainer:
	var h := HBoxContainer.new()
	var l := Label.new()
	l.text = caption
	l.custom_minimum_size = Vector2(150, 0)
	h.add_child(l)
	ctrl.size_flags_horizontal = Control.SIZE_EXPAND_FILL
	h.add_child(ctrl)
	return h


func _button(text: String, parent: Control, action: Callable) -> Button:
	var b := Button.new()
	b.text = text
	b.custom_minimum_size = Vector2(0, 42)
	b.size_flags_horizontal = Control.SIZE_EXPAND_FILL
	b.pressed.connect(action)
	parent.add_child(b)
	return b


## Eine Zeile für Meldungen, unten auf jedem Bildschirm.
func _status_row(box: VBoxContainer, key: String) -> void:
	var l := _text("", 14, Color(0.95, 0.55, 0.5))
	box.add_child(l)
	status_labels[key] = l


## Eine Reihe anklickbarer Zahlen - bei so wenigen Werten schneller als eine
## Spinbox mit ihren winzigen Pfeilen.
class NumberRow extends HBoxContainer:
	var value := 0
	var _buttons: Array[Button] = []
	var _lo := 0

	func _init(lo: int, hi: int, start: int) -> void:
		_lo = lo
		alignment = BoxContainer.ALIGNMENT_CENTER
		add_theme_constant_override("separation", 6)
		for n in range(lo, hi + 1):
			var b := Button.new()
			b.text = str(n)
			b.toggle_mode = true
			b.custom_minimum_size = Vector2(40, 38)
			b.pressed.connect(pick.bind(n))
			add_child(b)
			_buttons.append(b)
		pick(start)

	func pick(n: int) -> void:
		value = n
		for i in _buttons.size():
			_buttons[i].button_pressed = _lo + i == n

	## Obergrenze und Bedienbarkeit in einem Zug - getrennt würde der eine
	## Aufruf den anderen wieder aufheben.
	func anpassen(hi: int, on: bool) -> void:
		for i in _buttons.size():
			_buttons[i].disabled = not on or _lo + i > hi
		if value > hi:
			pick(maxi(_lo, hi))


func _title(box: VBoxContainer) -> void:
	box.add_child(_text("LIAR'S DICE 3D", 40))
	box.add_child(HSeparator.new())


func _build_main() -> Control:
	var box := _box(360)
	_title(box)
	_button("Einzelspieler", box, _show.bind("single"))
	_button("Mehrspieler", box, _show.bind("multi"))
	_button("Beenden", box, func() -> void: get_tree().quit())
	return box


func _build_single() -> Control:
	var box := _box(400)
	_title(box)
	box.add_child(_text("Einzelspieler", 22, Color(1.0, 0.82, 0.32)))
	box.add_child(_text("Bots", 15))
	solo_bots = NumberRow.new(1, BOT_NAMES_MAX, 3)
	box.add_child(solo_bots)
	box.add_child(HSeparator.new())
	var row := HBoxContainer.new()
	row.add_theme_constant_override("separation", 8)
	box.add_child(row)
	_button("Starten", row, _on_solo_start)
	_button("Zurück", row, _show.bind("main"))
	return box


## Erster Schritt: nur der Name, dann hosten oder beitreten.
func _build_multi() -> Control:
	var box := _box(440)
	_title(box)
	box.add_child(_text("Mehrspieler", 22, Color(1.0, 0.82, 0.32)))

	name_edit = LineEdit.new()
	name_edit.text = "Spieler"
	name_edit.placeholder_text = "Dein Name"
	box.add_child(_row("Name", name_edit))

	var brow := HBoxContainer.new()
	brow.add_theme_constant_override("separation", 8)
	box.add_child(brow)
	_button("Hosten", brow, _on_host)
	_button("Beitreten", brow, _show.bind("join"))

	_button("Zurück", box, _show.bind("main"))
	_status_row(box, "multi")
	return box


## Zweiter Schritt beim Beitreten: der Code vom Host.
func _build_join() -> Control:
	var box := _box(440)
	_title(box)
	box.add_child(_text("Beitreten", 22, Color(1.0, 0.82, 0.32)))
	box.add_child(_text("Den Code bekommst du vom Host.", 15,
		Color(0.65, 0.67, 0.72)))

	code_edit = LineEdit.new()
	code_edit.placeholder_text = "z. B. K7QM"
	code_edit.max_length = 6
	code_edit.alignment = HORIZONTAL_ALIGNMENT_CENTER
	code_edit.add_theme_font_size_override("font_size", 24)
	code_edit.text_submitted.connect(func(_t: String) -> void: _on_join())
	box.add_child(code_edit)

	var row := HBoxContainer.new()
	row.add_theme_constant_override("separation", 8)
	box.add_child(row)
	_button("Beitreten", row, _on_join)
	_button("Zurück", row, _show.bind("multi"))
	_status_row(box, "join")
	return box


## Dritter Schritt: warten, bis alle da sind.
func _build_lobby() -> Control:
	var box := _box(440)
	_title(box)
	box.add_child(_text("Lobby", 22, Color(1.0, 0.82, 0.32)))

	code_label = _text("", 34, Color(1.0, 0.82, 0.32))
	box.add_child(code_label)
	box.add_child(_text("Diesen Code an die Mitspieler geben.", 14,
		Color(0.65, 0.67, 0.72)))
	box.add_child(HSeparator.new())

	lobby_list = _text("-", 16, Color(0.85, 0.87, 0.92))
	box.add_child(lobby_list)
	box.add_child(HSeparator.new())

	box.add_child(_text("Bots", 15))
	lobby_bots = NumberRow.new(0, BOT_NAMES_MAX, 1)
	box.add_child(lobby_bots)

	var row := HBoxContainer.new()
	row.add_theme_constant_override("separation", 8)
	box.add_child(row)
	start_btn = _button("Spiel starten", row, _on_start)
	_button("Verlassen", row, _on_leave)
	_status_row(box, "lobby")
	return box


# ------------------------------------------------------------ Aktionen

func _on_solo_start() -> void:
	Net.start_singleplayer("Spieler", solo_bots.value)


## Ein leeres Namensfeld ergäbe einen namenlosen Platz am Tisch.
func _spielername() -> String:
	var n := name_edit.text.strip_edges()
	return n if n != "" else "Spieler"


func _on_host() -> void:
	_sagen("Raum wird angelegt ...")
	Net.create_room(_spielername())


func _on_join() -> void:
	_sagen("Verbinde ...")
	Net.join_room(code_edit.text, _spielername())


func _on_leave() -> void:
	Net.leave()
	_show("multi")


func _on_start() -> void:
	var humans: int = Net.lobby.size()
	var ai: int = mini(lobby_bots.value, Net.MAX_HUMANS - humans)
	if humans + ai < 2:
		_sagen("Mindestens 2 Spieler nötig (Mitspieler oder Bots).")
		return
	Net.request_start(ai)


func _on_failed(msg: String) -> void:
	_sagen(msg)


func _on_closed() -> void:
	_show("multi")
	_sagen("Der Raum wurde geschlossen.")


## Sobald der Server uns kennt, sind wir in der Lobby.
func _refresh() -> void:
	if lobby_list == null:
		return
	var drin := Net.is_online() and Net.lobby.has(multiplayer.get_unique_id())
	if drin and current != "lobby":
		_show("lobby")
	elif not drin and current == "lobby":
		_show("multi")
	if current != "lobby":
		return

	code_label.text = Net.room_code
	start_btn.disabled = not Net.is_owner
	lobby_bots.anpassen(Net.MAX_HUMANS - Net.lobby.size(), Net.is_owner)

	var names: Array = []
	for id: int in Net.lobby:
		names.append("%s%s" % [Net.lobby[id], "  (Host)" if id == Net.owner_id else ""])
	lobby_list.text = "\n".join(names)
	if not Net.is_owner:
		_sagen("Der Host startet die Partie.")