from gamedata.objects.base import BaseObject

import math

class Skies(BaseObject):

    def __init__(self,game,basesky="skies/base.png",nightsky="skies/night.png",daysky="skies/day.png"):
        super().__init__(0,0,game,game.DISPLAY_WIDTH,game.DISPLAY_HEIGHT)
        size = [game.DISPLAY_WIDTH,game.DISPLAY_HEIGHT]
        self.basesky = game.pygame.transform.scale(game.sprite_lib[basesky],size)
        self.nightsky = game.pygame.transform.scale(game.sprite_lib[nightsky],size)
        self.daysky = game.pygame.transform.scale(game.sprite_lib[daysky],size)

        self.blackrect = game.pygame.Surface(size)
        self.blackrect.fill([0]*3)

        self.speed = 0.02
        self.timeelapsed = 0

        self.depth = -2

        self.blackrectalpha = 0.5

    def step(self):

        self.timeelapsed+=self.game.dt

        self.cosvalue = math.cos(self.timeelapsed*self.speed)

    def draw(self):

        self.game.window.blit(self.basesky,[0,0])
        if self.cosvalue<0:
            self.nightsky.set_alpha(-self.cosvalue*255)
            self.game.window.blit(self.nightsky,[0,0])
        else:
            self.daysky.set_alpha(self.cosvalue*255)
            self.game.window.blit(self.daysky,[0,0])

    def afterdraw(self):
        if self.cosvalue<0:
            self.blackrect.set_alpha(-self.cosvalue*255*self.blackrectalpha)
            self.game.realwindow.blit(self.blackrect,[0,0])