#!/usr/bin/env python

import random
import pygame
import sys

screen_width = 640
screen_height = 480
screen_size = screen_width, screen_height

screen = None
ready_text = None

def start():
    global screen, ready_text
    pygame.init()
    screen = pygame.display.set_mode( screen_size )
    font = pygame.font.Font( None, screen_height / 5 )
    ready_text = font.render( "Ready?", 1, pygame.Color( "white" ) )

def quit():
    pygame.quit()
    sys.exit()

def ready_screen():
    textpos = ready_text.get_rect(
        centerx = screen.get_width() / 2,
        centery = screen.get_height() / 2
    )

    screen.blit( ready_text, textpos )
    pygame.display.flip()

def wait():
    time_to_wait = random.randint( 1500, 3000 ) # Between 1.5 and 3 seconds
    pygame.time.wait( time_to_wait ) # Note bug: can't quit during this time

def shape_wait():
    """
    Wait while we display a shape.  Return True if a key was pressed,
    or false otherwise.
    """

    event_types_that_cancel = pygame.KEYDOWN, pygame.MOUSEBUTTONDOWN

    time_to_wait = 2000 # Display the shape for 2 seconds
    finished_waiting_event_id = pygame.USEREVENT + 1
    pygame.time.set_timer( finished_waiting_event_id, time_to_wait )

    pressed = False
    waiting = True
    while waiting:
        evt = pygame.event.wait()
        if evt.type == pygame.QUIT:
            quit()
        elif evt.type in event_types_that_cancel:
            waiting = False
            pressed = True
        elif evt.type == finished_waiting_event_id:
            waiting = False

    pygame.time.set_timer( finished_waiting_event_id, 0 )

    return pressed


def tick():
    colour = pygame.Color( "green" )
    w = screen.get_width() / 2
    h = screen.get_height() / 2
    points = (
        ( w - w/5, h - h/9 ),
        ( w,       h + h/5 ),
        ( w + w/3, h - h/3 ),
    )

    screen.fill( pygame.Color( "black" ) )
    pygame.draw.lines( screen, colour, False, points, 20 )
    pygame.display.flip()


def cross():
    colour = pygame.Color( "red" )
    w = screen.get_width() / 2
    h = screen.get_height() / 2
    left   = w - w/3
    right  = w + w/3
    top    = h - h/3
    bottom = h + h/3

    start1 = left, top
    end1   = right, bottom

    start2 = left, bottom
    end2   = right, top

    screen.fill( pygame.Color( "black" ) )
    pygame.draw.line( screen, colour, start1, end1, 20 )
    pygame.draw.line( screen, colour, start2, end2, 20 )
    pygame.display.flip()

def green_success():
    tick()
    pygame.time.wait( 2000 ) # Can't quit or skip!

def green_failure():
    cross()
    pygame.time.wait( 2000 ) # Can't quit or skip!

def green_shape():
    green = pygame.Color( "green" )
    centre = ( screen.get_width() / 2, screen.get_height() / 2 )
    radius = screen.get_width() / 3

    screen.fill( pygame.Color( "white" ) )
    pygame.draw.circle( screen, green, centre, radius, 0 )

    pygame.display.flip()

    pressed = shape_wait()

    if pressed:
        green_success()
    else:
        green_failure()

def shape():
    green_shape()

def end():
    pygame.event.clear()
    event_types_that_cancel = pygame.KEYDOWN, pygame.MOUSEBUTTONDOWN
    waiting = True
    while waiting:
        evt = pygame.event.wait()
        if evt.type == pygame.QUIT:
            quit()
        elif evt.type in event_types_that_cancel:
            waiting = False

start()

ready_screen()

wait()

shape()

end()