from textual.app import App, ComposeResult
from textual.screen import Screen
from textual.widgets import Footer, Placeholder


class DashboardScreen(Screen):
    def compose(self) -> ComposeResult:
        yield Placeholder("Dashboard Screen")
        yield Footer()


class SettingsScreen(Screen):
    def compose(self) -> ComposeResult:
        yield Placeholder("Settings Screen")
        yield Footer()


class HelpScreen(Screen):
    def compose(self) -> ComposeResult:
        yield Placeholder("Help Screen")
        yield Footer()


class ModesApp(App):
    BINDINGS = [
        ("d", "switch_mode('dashboard')", "Dashboard"),  # (1)!
        ("s", "switch_mode('settings')", "Settings"),
        ("h", "switch_mode('help')", "Help"),
    ]
    MODES = {
        "dashboard": DashboardScreen,  # (2)!
        "settings": SettingsScreen,
        "help": HelpScreen,
    }

    def on_mount(self) -> None:
        self.switch_mode("dashboard")  # (3)!


if __name__ == "__main__":
    app = ModesApp()
    app.run()