Add multi-select batch fish selling

ui/fish_batch_selection.gd

@@ -0,0 +1,106 @@
+class_name FishBatchSelection
+extends RefCounted
+
+var _selected_ids: Dictionary[StringName, bool] = {}
+var _visible_ids: Array[StringName] = []
+var _focused_id: StringName
+var _anchor_id: StringName
+
+
+func set_visible_order(visible_ids: Array[StringName]) -> void:
+	_visible_ids = visible_ids.duplicate()
+	var visible_set: Dictionary[StringName, bool] = {}
+	for catch_id: StringName in _visible_ids:
+		if not catch_id.is_empty():
+			visible_set[catch_id] = true
+	for catch_id: StringName in _selected_ids.keys():
+		if not visible_set.has(catch_id):
+			_selected_ids.erase(catch_id)
+	if not visible_set.has(_focused_id):
+		_focused_id = StringName()
+	if not visible_set.has(_anchor_id):
+		_anchor_id = StringName()
+
+
+func apply_click(
+	catch_id: StringName,
+	ctrl_pressed: bool,
+	shift_pressed: bool,
+) -> void:
+	if catch_id.is_empty() or not _visible_ids.has(catch_id):
+		return
+	if not shift_pressed or _anchor_id.is_empty():
+		if ctrl_pressed:
+			if _selected_ids.has(catch_id):
+				_selected_ids.erase(catch_id)
+			else:
+				_selected_ids[catch_id] = true
+		else:
+			_selected_ids.clear()
+			_selected_ids[catch_id] = true
+		_focused_id = catch_id
+		_anchor_id = catch_id
+		return
+
+	var anchor_index: int = _visible_ids.find(_anchor_id)
+	var target_index: int = _visible_ids.find(catch_id)
+	if anchor_index < 0 or target_index < 0:
+		select_only(catch_id)
+		return
+	if not ctrl_pressed:
+		_selected_ids.clear()
+	var first_index: int = mini(anchor_index, target_index)
+	var last_index: int = maxi(anchor_index, target_index)
+	for index: int in range(first_index, last_index + 1):
+		_selected_ids[_visible_ids[index]] = true
+	_focused_id = catch_id
+
+
+func select_only(catch_id: StringName) -> void:
+	_selected_ids.clear()
+	if catch_id.is_empty() or not _visible_ids.has(catch_id):
+		_focused_id = StringName()
+		_anchor_id = StringName()
+		return
+	_selected_ids[catch_id] = true
+	_focused_id = catch_id
+	_anchor_id = catch_id
+
+
+func clear() -> void:
+	_selected_ids.clear()
+	_focused_id = StringName()
+	_anchor_id = StringName()
+
+
+func remove_ids(catch_ids: Array[StringName]) -> void:
+	for catch_id: StringName in catch_ids:
+		_selected_ids.erase(catch_id)
+		if _focused_id == catch_id:
+			_focused_id = StringName()
+		if _anchor_id == catch_id:
+			_anchor_id = StringName()
+
+
+func get_selected_ids() -> Array[StringName]:
+	var selected_in_order: Array[StringName] = []
+	for catch_id: StringName in _visible_ids:
+		if _selected_ids.has(catch_id):
+			selected_in_order.append(catch_id)
+	return selected_in_order
+
+
+func is_selected(catch_id: StringName) -> bool:
+	return _selected_ids.has(catch_id)
+
+
+func get_selected_count() -> int:
+	return _selected_ids.size()
+
+
+func get_focused_id() -> StringName:
+	return _focused_id
+
+
+func get_anchor_id() -> StringName:
+	return _anchor_id