santa.py

#!/usr/bin/env python
# encoding: utf-8
"""
santa.py

Created by Chris Amico on 2010-12-10.

Use at your own risk.
"""
import csv
import random
import sys
import os

class Santa(object):
    """
    Given a list of name/email pairs,
    assign people to give each other
    gifts.
    
    Can also email everyone.
    
    >>> from santa import Santa
    >>> people = (
    ...     ('Chris', '[email protected]'),
    ...     ('Dave', '[email protected]'),
    ...     ('Vanessa', '[email protected]'),
    ... )
    >>> santa = Santa(people)
    >>> santa.sort()
    # random results should come back
    
    """
    def __init__(self, people):
        self.people = dict(people)
        self.gifters = set(self.people.keys())
        self.getters = set(self.people.keys())
        self.results = dict()
    
    def sort(self):
        while self.gifters:
            giver = random.choice(list(self.gifters))
            getter = random.choice(list(self.getters))
            if not giver == getter:
                self.gifters.remove(giver)
                self.getters.remove(getter)
                self.results[giver] = getter
        
        return self.results
    

def main():
    with open(sys.argv[1]) as f:
        reader = csv.reader(f)
        people = (row for row in reader)
        santa = Santa(people)
        santa.sort()
        for result in santa.results.items():
            print("%s gives to %s" % result)


if __name__ == '__main__':
    main()