Raphaël G. Git Repositories - youtubedl/blob - devscripts/youtube_genalgo.py

   1 #!/usr/bin/env python
   2
   3 # Generate youtube signature algorithm from test cases
   4
   5 import sys
   6
   7 tests = [
   8     # 88
   9     ("qwertyuioplkjhgfdsazxcvbnm1234567890QWERTYUIOPLKJHGFDSAZXCVBNM!@#$%^&*()_-+={[]}|:;?/>.<",
  10      "J:|}][{=+-_)(*&;%$#@>MNBVCXZASDFGH^KLPOIUYTREWQ0987654321mnbvcxzasdfghrklpoiuytej"),
  11     # 87
  12     ("qwertyuioplkjhgfdsazxcvbnm1234567890QWERTYUIOPLKJHGFDSAZXCVBNM!@#$^&*()_-+={[]}|:;?/>.<",
  13      "!?;:|}][{=+-_)(*&^$#@/MNBVCXZASqFGHJKLPOIUYTREWQ0987654321mnbvcxzasdfghjklpoiuytr"),
  14     # 86 - vfl_ymO4Z 2013/06/27
  15     ("qwertyuioplkjhgfdsazxcvbnm1234567890QWERTYUIOPLKJHGFDSAZXCVBNM!@#$%^&*()_-+={[|};?/>.<",
  16      "ertyuioplkjhgfdsazxcvbnm1234567890QWERTYUIOPLKJHGFDSAZXCVBNM!/#$%^&*()_-+={[|};?@"),
  17     # 85
  18     ("qwertyuioplkjhgfdsazxcvbnm1234567890QWERTYUIOPLKJHGFDSAZXCVBNM!@#$%^&*()_-+={[};?/>.<",
  19      "{>/?;}[.=+-_)(*&^%$#@!MqBVCXZASDFwHJKLPOIUYTREWQ0987654321mnbvcxzasdfghjklpoiuytr"),
  20     # 84
  21     ("qwertyuioplkjhgfdsazxcvbnm1234567890QWERTYUIOPLKJHGFDSAZXCVBNM!@#$%^&*()_-+={[};?>.<",
  22      "<.>?;}[{=+-_)(*&^%$#@!MNBVCXZASDFGHJKLPOIUYTREWe098765432rmnbvcxzasdfghjklpoiuyt1"),
  23     # 83
  24     ("qwertyuioplkjhgfdsazxcvbnm1234567890QWERTYUIOPLKJHGFDSAZXCVBNM!#$%^&*()_+={[};?/>.<",
  25      "D.>/?;}[{=+_)(*&^%$#!MNBVCXeAS<FGHJKLPOIUYTREWZ0987654321mnbvcxzasdfghjklpoiuytrQ"),
  26     # 82
  27     ("qwertyuioplkjhgfdsazxcvbnm1234567890QWERTYUIOPLKHGFDSAZXCVBNM!@#$%^&*(-+={[};?/>.<",
  28      "Q>/?;}[{=+-(*<^%$#@!MNBVCXZASDFGHKLPOIUY8REWT0q&7654321mnbvcxzasdfghjklpoiuytrew9"),
  29 ]
  30
  31 def find_matching(wrong, right):
  32     idxs = [wrong.index(c) for c in right]
  33     return compress(idxs)
  34     return ('s[%d]' % i for i in idxs)
  35
  36 def compress(idxs):
  37     def _genslice(start, end, step):
  38         starts = '' if start == 0 else str(start)
  39         ends = ':%d' % (end+step)
  40         steps = '' if step == 1 else (':%d' % step)
  41         return 's[%s%s%s]' % (starts, ends, steps)
  42
  43     step = None
  44     for i, prev in zip(idxs[1:], idxs[:-1]):
  45         if step is not None:
  46             if i - prev == step:
  47                 continue
  48             yield _genslice(start, prev, step)
  49             step = None
  50             continue
  51         if i - prev in [-1, 1]:
  52             step = i - prev
  53             start = prev
  54             continue
  55         else:
  56             yield 's[%d]' % prev
  57     if step is None:
  58         yield 's[%d]' % i
  59     else:
  60         yield _genslice(start, i, step)
  61
  62 def _assert_compress(inp, exp):
  63     res = list(compress(inp))
  64     if res != exp:
  65         print('Got %r, expected %r' % (res, exp))
  66         assert res == exp
  67 _assert_compress([0,2,4,6], ['s[0]', 's[2]', 's[4]', 's[6]'])
  68 _assert_compress([0,1,2,4,6,7], ['s[:3]', 's[4]', 's[6:8]'])
  69 _assert_compress([8,0,1,2,4,7,6,9], ['s[8]', 's[:3]', 's[4]', 's[7:5:-1]', 's[9]'])
  70
  71 def gen(wrong, right, indent):
  72     code = ' + '.join(find_matching(wrong, right))
  73     return 'if len(s) == %d:\n%s    return %s\n' % (len(wrong), indent, code)
  74
  75 def genall(tests):
  76     indent = ' ' * 8
  77     return indent + (indent + 'el').join(gen(wrong, right, indent) for wrong,right in tests)
  78
  79 def main():
  80     print(genall(tests))
  81
  82 if __name__ == '__main__':
  83     main()