MoinMoin: macro/Sum.py

   1 """
   2     MoinMoin - Sum Macro
   3 
   4     Copyright (c) 2003 by Michael Schuerig <schuerig@acm.org>
   5     All rights reserved, see COPYING for details.
   6 
   7     Sum and convert money amounts.
   8     Usage:
   9     [[Sum(amount)]] # Add amount in the base currency
  10     [[Sum(amount, currency)]] # Add amount in the given currency (three char code)
  11     [[Sum]] # Insert the sum in the base currency
  12 
  13     This macro requires the existence of page named ExchangeRates
  14     with raw content like this:
  15 
  16 #format text
  17 PACIFIC Exchange Rate Service
  18 YYYY/MM/DD      2003/01/17
  19 EUR/DEM 0.51129
  20 EUR/GBP 1.5174
  21 EUR/USD 0.93788
  22 (C) 2003 PACIFIC - Univ. of British Columbia
  23 
  24     You can get the contents of that page from
  25     
  26     http://blacktusk.commerce.ubc.ca/cgi-bin/fxdata?rd=1&f=tab&q=price&y=daily&g=z&b=EUR
  27 
  28     If someone has an idea for regularly auto-updating that
  29     page, please share it.
  30 """
  31 
  32 from MoinMoin.Page import Page
  33 
  34 class XchRates:
  35 
  36     def __init__(self):
  37         self.__baseCurrency = "EUR"
  38         self.__ratesPageName = "ExchangeRates"
  39         self.rates = {}
  40         self.__loadRates()
  41         self.rates[self.__baseCurrency] = 1.0
  42 
  43     def rate(self, currency):
  44         if self.hasRate(currency):
  45             return self.rates[currency]
  46         else:
  47             return 0.0
  48 
  49     def hasRate(self, currency):
  50         return self.rates.has_key(currency)
  51 
  52     def convertFrom(self, amount, currency=None):
  53         if currency == None: currency = self.__baseCurrency
  54         return amount * self.rate(currency)
  55     
  56     def formatMoney(self, amount, currency=None):
  57         if currency == None: currency = self.__baseCurrency
  58         if self.hasRate(currency):
  59             return ("%s %.2f" % (currency, amount))
  60         else:
  61             return ("%s %.2f (NO EXCHANGE RATE AVAILABLE; NOT ADDED)"
  62                     % (currency, amount))
  63     
  64     def __loadRates(self):
  65         ratesPage = Page(self.__ratesPageName).get_raw_body().strip()
  66         # ignore first line containing "#format plain"
  67         self.__parseRates(ratesPage.splitlines()[1:])
  68 
  69     def __parseRates(self, lines):
  70         for l in lines[2:-1]:
  71             self.__parseRate(l.strip())
  72 
  73     def __parseRate(self, l):
  74         baseByCur,rate = l.split("\t")
  75         base,cur = baseByCur.split("/")
  76         if rate != ".":
  77             self.rates[cur] = float(rate)
  78 
  79 
  80 def execute(macro, args):
  81     if not hasattr(macro.request, 'sum'):
  82         macro.request.sum = 0.0
  83         macro.request.xch = XchRates()
  84 
  85     xch = macro.request.xch
  86     
  87     if not args:
  88         return xch.formatMoney(macro.request.sum)
  89     else:
  90         # add to running sum and emit addend
  91         a = args.split(",")
  92         amount = float(a[0])
  93         currency = None
  94         if len(a) == 2:
  95             currency = a[1].strip().upper()
  96         macro.request.sum += xch.convertFrom(amount, currency)
  97         return xch.formatMoney(amount, currency)