from tuikit.core.window import Window

import logging

class Application:

    """Tuikit application helper.

    Joins all required pieces to build complete application

    using TUI widgets and event loop.

    """

    def __init__(self, driver='curses'):

        # logger

        self.log = logging.getLogger('tuikit')

        # Driver

        self.driver = None

        # root Buffer and Window

        self.root_window = Window()

        # flags

        self._started = False

        self._quit = False

        # find and initialize driver

        self.use_driver(driver)

    def use_driver(self, driver_name):

        """Select driver to be used for rendering and input.

        `driver_name` should be one of: 'base', 'curses', 'sdl'

        """

        if self._started:

            raise Exception('Cannot change driver after starting the application.')

        module = __import__('tuikit.driver.' + driver_name, fromlist=['driver_class'])

        self.driver = module.driver_class()

    def start(self):

        """Start application. Runs main loop."""

        self.log.info('=== start ===')

        with self.driver:

            self.main_loop()

    def stop(self):

        """Terminate application."""

        self._quit = True

    def main_loop(self):

        """The main loop."""

        self._started = True

        self.root_window.resize(*self.driver.size)

#        timer = self._timer

        self.root_window.buffer.frame()

        while not self._quit:

            self.root_window.draw(self.driver)

            self.driver.flush()

            #timeout = timer.nearest_timeout()

            events = self.driver.getevents()#timeout)

            self._quit = True

            #timer.process_timeouts()

#            for event in events:

 #               self._top.emit(event[0], *event[1:])

        self._started = False

        self.log.info('=== quit ===')