src/librarian/covers/widgets/background.py

   1 import io
   2 import time
   3 from urllib.request import urlopen
   4 import PIL.Image
   5 from .base import Widget
   6
   7
   8 class Background(Widget):
   9     transparency = False
  10
  11     def __init__(self, cover, crop_to_square=True):
  12         self.crop_to_square = crop_to_square
  13         super().__init__(cover)
  14
  15     def setup(self):
  16         self.img = None
  17         if self.cover.book_info.cover_url:
  18             while True:
  19                 try:
  20                     data = io.BytesIO(urlopen(self.cover.book_info.cover_url, timeout=3).read())
  21                 except:
  22                     time.sleep(2)
  23                 else:
  24                     break
  25
  26             img = PIL.Image.open(data)
  27
  28             if self.crop_to_square:
  29                 # crop top square.
  30                 if img.size[1] > img.size[0]:
  31                     img = img.crop((0, 0, img.size[0], img.size[0]))
  32                 else:
  33                     left = round((img.size[0] - img.size[1])/2)
  34                     img = img.crop((
  35                         left,
  36                         0,
  37                         left + img.size[1],
  38                         img.size[1]
  39                     ))
  40             self.img = img
  41
  42     def build(self, w, h):
  43         if not self.img:
  44             return
  45         img = self.img
  46         scale = max(
  47             w / img.size[0],
  48             h / img.size[1]
  49         )
  50         img = self.img.resize((
  51             round(scale * img.size[0]),
  52             round(scale * img.size[1]),
  53         ))
  54         img = img.crop((
  55             int((img.size[0] - w) / 2),
  56             0,
  57             w + int((img.size[0] - w) / 2),
  58             h))
  59
  60         return img