from typing import Optional, Callable, Awaitable

from nicegui import ui


class ChatInput(ui.textarea):

    def __init__(self,
                 placeholder: str = 'Type your message...',
                 on_enter: Optional[Callable[[str], Awaitable[None]]] = None,
                 *args, **kwargs) -> None:
        super().__init__(placeholder=placeholder, *args, **kwargs)
        self._on_enter_callback = on_enter
        self.classes('flex-grow').props('outlined dense autogrow')
        self.on('keydown', self._handle_keydown)

    async def _handle_keydown(self, event) -> None:
        """Handle keyboard shortcuts for message input"""
        if hasattr(event, 'args') and event.args:
            key_event = event.args
            if key_event.get('key') == 'Enter' and not key_event.get('shiftKey', False):
                # Enter without Shift: Send message
                event.args['preventDefault'] = True
                if self._on_enter_callback and self.value:
                    await self._on_enter_callback(self.value)
                    self.value = ''
        # Shift+Enter: Allow default behavior (new line)