import pygame as pg
import pygame.freetype
import traceback

vec = pg.math.Vector2

# initial resolutions
WINDOW_W = 800
WINDOW_H = 480


def vec_to_int(vector):
    return int(vector.x), int(vector.y)


class Game:
    def __init__(self):
        pg.init()
        # initial window flags
        self.flags = pg.VIDEORESIZE
        # application window surface
        self.app_screen = pg.display.set_mode((WINDOW_W, WINDOW_H),
                                              self.flags)
        self.app_screen_rect = self.app_screen.get_rect()
        self.clock = pg.time.Clock()
        self.running = True
        self.font = pygame.freetype.SysFont('arial', size=64)
        self.mpos = vec()
        self.mouse_visible = True

    def events(self):
        for event in pg.event.get():
            if event.type == pg.QUIT:
                self.running = False
            elif event.type == pg.KEYDOWN:
                if event.key == pg.K_ESCAPE:
                    self.running = False
                elif event.key == pg.K_f:
                    # toggle fullscreen
                    self.flags = self.flags ^ pg.FULLSCREEN
                    self.reset_app_screen(self.app_screen_rect.size)
                elif event.key == pg.K_m:
                    # toggle mouse visibility
                    self.mouse_visible = not self.mouse_visible
                    pg.mouse.set_visible(self.mouse_visible)
            elif event.type == pg.VIDEORESIZE:
                # if the user resizes the window (drag the bottom right corner)
                # get the new size from the event dict and reset the
                # window screen surface
                self.reset_app_screen(event.dict['size'])

    def reset_app_screen(self, size):
        self.app_screen = pg.display.set_mode(size, self.flags)
        self.app_screen_rect = self.app_screen.get_rect()
        pg.display.update()

    def update(self, dt):
        self.mpos = vec(pg.mouse.get_pos())

    def draw(self):
        self.app_screen.fill(pg.Color('Purple'))
        # draw a circle following the mouse
        if pg.mouse.get_pressed()[0]:
            color = 'darkred'
        else:
            color = 'skyblue'
        pg.draw.circle(self.app_screen, pg.Color(color),
                       vec_to_int(self.mpos), 60)
        # text that indicates if the mouse is visible
        txt, rect = self.font.render(f'mouse visible: {self.mouse_visible}',
                                     fgcolor=pg.Color('white'))
        rect.midbottom = self.app_screen_rect.midbottom - vec(0, 20)
        self.app_screen.blit(txt, rect)
        pg.display.update()

    def run(self):
        while self.running:
            delta_time = self.clock.tick() / 1000
            self.events()
            self.update(delta_time)
            self.draw()
        pg.quit()


if __name__ == '__main__':
    try:
        g = Game()
        g.run()
    except:
        traceback.print_exc()
        pg.quit()