git.maemo.org Git - pywienerlinien/blob - gotovienna/cache.py

   1 from os import path
   2 import json
   3 import shutil
   4 import defaults
   5 import realtime
   6
   7
   8 def load(path):
   9     if path.exists(path, typ):
  10         try:
  11             with open(path, 'r') as f:
  12                 j = json.load(f)
  13                 if type(j) == typ:
  14                     return j
  15                 else:
  16                     print 'Unexpected content in cache file'
  17                     print 'rebuilding cache'
  18                     shutil.copy(path, path + '.bak')
  19         except ValueError:
  20             print 'Corrupt cache file'
  21             print 'rebuilding cache'
  22             shutil.copy(path, path + '.bak')
  23
  24     return None
  25
  26 class Lines(list):
  27     def __init__(self, lines=[]):
  28         l = load(defaults.cache_line)
  29         if l and type(l) == list:
  30             lines = l
  31         self.lines = lines
  32
  33     def __iter__(self):
  34         for line in self.lines:
  35             yield line
  36         raise StopIteration()
  37
  38     def __iadd__(self, y):
  39         self.lines += y
  40
  41     def __add__(self, y):
  42         return self.lines + y
  43
  44     def __getitem__(self, y):
  45         return self.lines[y]
  46
  47     def __len__(self):
  48         return len(self.lines)
  49
  50     def __str__(self):
  51         return str(self.lines)
  52
  53     def __setitem__(self, i, y):
  54         self.lines[i] = y
  55
  56 class Stations(dict):
  57     stations = {}
  58
  59     def __init__(self, line=False):
  60         """ loads cache files
  61         if line=False behaves as dict of all lines/stations
  62         if line behaves as dict of directions/stations of line
  63         """
  64         if not Stations.stations:
  65             s = load(defaults.cache_line, dict)
  66             if s:
  67                 Stations.stations = st
  68
  69         self.current_line = line
  70         if line == False:
  71             self.dict = Stations.stations
  72         elif line in Stations.stations:
  73             self.dict = Stations.stations[line]
  74         else:
  75             Stations.stations[line] = {}
  76             self.dict = Stations.stations[line]
  77
  78
  79     def __getitem__(self, *args, **kwargs):
  80         return self.dict.__getitem__(self, *args, **kwargs)