from tuikit.core.buffer import Buffer

from tuikit.core.signal import Signal

class Window:

    """Window is rectangular part of screen containing widgets.

    Widgets are drawn into window, events are routed to widgets through window.

    """

    def __init__(self, buffer=None):

        """New buffer for the window will be created unless given existing

        `buffer` as parameter."""

        self._buffer = None

        self._size = None

        self.sig_resized = Signal()

        self.buffer = buffer or Buffer()

    @property

    def buffer(self):

        return self._buffer

    @buffer.setter

    def buffer(self, buffer):

        # disconnect signals from old buffer

        if self._buffer:

            self.sig_resized.disconnect(self._buffer.resize)

        # replace the buffer

        self._buffer = buffer

        self._size = buffer.size

        # resize buffer when window gets resized

        self.sig_resized.connect(buffer.resize)

    @property

    def size(self):

        return self._size.readonly()

    def resize(self, w, h):

        self._buffer.resize(w, h)

        self.sig_resized(w, h)

    def draw(self, buffer, x=0, y=0):

        """Draw this window into buffer at x, y coords."""

        buffer.draw(self.buffer, x, y)