# Standard Library 
from dataclasses import dataclass
from typing import List, Callable, Protocol

# External Library
from PySide6.QtWidgets import (QToolBar, QMainWindow, QWidget, QMdiArea,  QMdiSubWindow)
from PySide6.QtGui import (QAction)

class UIComponent(Protocol):
    def build(self, app: QMainWindow):
        pass

@dataclass
class ToolbarAction:
    name: str
    callback: Callable[[QMainWindow], None]

@dataclass
class Toolbar(UIComponent):
    name: str
    actions: List[ToolbarAction]

    def build(self, app: QMainWindow):
        toolbar = QToolBar(self.name)
        for action in self.actions:
            qt_action = QAction(action.name, app)
            qt_action.triggered.connect(lambda checked=False, cb=action.callback: cb(app))
            toolbar.addAction(qt_action)
        app.addToolBar(toolbar)

@dataclass
class SubWindow(UIComponent):
    name: str
    content_factory: Callable[[], QWidget]

    def build(self, app: QMainWindow):
        if not hasattr(app, 'mdi_area'):
            raise AttributeError("MDI area not found in app")

        mdi_area: QMdiArea = getattr(app, 'mdi_area')
        sub_window = QMdiSubWindow()
        sub_window.setWidget(self.content_factory())
        sub_window.setWindowTitle(self.name)
        mdi_area.addSubWindow(sub_window)
        sub_window.show()

@dataclass
class Window(UIComponent):
    title: str

    def build(self, app: QMainWindow):
        app.setWindowTitle(self.title)

@dataclass
class Characteristics:
    components: List[UIComponent]