import pygame
import subprocess
import steam_saver.surfaces as surfaces

# Global variables
FPS = 60
VALID_SURFACES = [
    'steam_screen'
]

def get_screen_resolution():
    command_output = subprocess.check_output(['xrandr']).decode('utf-8')
    for line in command_output.split('\n'):
        if '*' in line:
            return tuple(map(int, line.split()[0].split('x')))

def main(windowed_mode=False):
    """
    Main scene manager to display the scenes of the application
    :param windowed_mode: boolean to start the game in windowed mode
    """
    pygame.init()
    clock = pygame.time.Clock()

    screen_size = get_screen_resolution()

    if windowed_mode:
        window = pygame.display.set_mode(screen_size)
    else:
        window = pygame.display.set_mode(screen_size, pygame.FULLSCREEN)

    # Starts the program with the surface 'steam_screen' as the default
    surface = getattr(globals()['surfaces'], 'steam_screen').Surface(screen_size)
    running = True
    while running:
        clock.tick(FPS)
        surface.update()

        window.blit(surface, surface.get_rect())

        if not surface.running:
            if surface.quit:
                break
            # Switch the surface to a new surface
            next_surface = surface.next_surface
            if next_surface not in VALID_SURFACES:
                raise Exception('Given surface is not a valid surface!')
            surface = getattr(globals()['surfaces'], next_surface).Surface(screen_size)

        pygame.display.flip()
    pygame.quit()