from .fonts import *
from .colors import *
import pygame
import math

MAX_COUNT = 9

class Athmos:

    def __init__(self, screen):
        self.index = 0
        self.filenames = []
        self.screen = screen
        self.show_list = True
        self.surface = pygame.Surface((0,0), pygame.SRCALPHA)

    def set_filenames(self,filenames):
        self.filenames = filenames
        self.surface = pygame.Surface(
            (self.screen.get_width()*2/3, self.get_display_count()*40),
            pygame.SRCALPHA)

    def get_display_count(self):
        return min(MAX_COUNT, len(self.filenames))

    def update(self):
        if self.show_list:
            self.surface.fill("black")
            for i in range(self.get_display_count()):
                text = self.filenames[(i-self.index-math.floor(self.get_display_count()/2))%len(self.filenames)]
                if i == math.floor(self.get_display_count()/2):
                    text_surface = font_helvetica16.render(text, False, "black", color_primary_light)
                else:
                    text_surface = font_helvetica16.render(text, False, color_primary_light)
                    opacity = math.floor((i+1) * 2 * 255 / MAX_COUNT
                                         if i < MAX_COUNT/2
                                         else (MAX_COUNT-i) * 2 * 255 / MAX_COUNT)
                    text_surface.set_alpha(opacity)
                self.surface.blit(text_surface, ((0, self.surface.get_height()/self.get_display_count()*i)))

            self.screen.blit(self.surface, (self.screen.get_width()/3,
                            (self.screen.get_height() - self.surface.get_height())/2))