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