best_match.py

import re

_locale_delim_re = re.compile(r'[_-]')

def _value_matches(value, item):
    def _normalize(language):
        # print "_locale_delim_re.split(language.lower()): " + str(_locale_delim_re.split(language.lower()))
        return _locale_delim_re.split(language.lower())[0]
    
    # print "item == '*': " + str(item == '*')
    # print "_normalize(value): " + str(_normalize(value))
    # print "_normalize(item): " + str(_normalize(item))
    # print "item == '*' or _normalize(value) == _normalize(item): " + str(item == '*' or _normalize(value) ==_normalize(item))
    return item == '*' or _normalize(value) == _normalize(item)

def best_match(self, matches, default=None):
    """Returns the best match from a list of possible matches based
    on the quality of the client.  If two items have the same quality,
    the one is returned that comes first.

    :param matches: a list of matches to check for
    :param default: the value that is returned if none match
    """
    best_quality = -1
    result = default
    for server_item in matches:
        # print 'server_item: ' + str(server_item)
        for client_item, quality in self:
            # print 'client_item, quality: '+ str(client_item) +", " + str(quality)
            if quality <= best_quality:
                break
            if _value_matches(server_item, client_item) \
               and quality > 0:
                best_quality = quality
                result = server_item
    return result

print "best_match_ex0: " + best_match([('de-AT',1),('de',.8)],['de','en','es'])
print "best_match_ex1: " + best_match([('de-AT',1),('de',.8)],['de-AT','en','es'])
print "best_match_ex2: " + best_match([('en-us',1)],['en', 'de'])
print "best_match_ex3: " + best_match([('en',1)],['en-us', 'de'])

output:
best_match_ex0: de
best_match_ex1: de-AT
best_match_ex2: en
best_match_ex3: en-us

best_match([('de-LU', 1), ('de-DE', 0.7), ('en', 0.3)], ['en', 'de', 'de-DE'])
returns
'de'

but expected
'de-DE'