def get_keywords(form, name):

	"""extract keywords associate with field name 'name'."""

	kws = form.getvalue(name)

	if not isinstance(kws, type([])):

		if kws:

			kws = [kws]

		else:

			kws = []

	return map(int, kws)

def set_selection(db, bk, sel, exc = []):

	"""select keywords selected in the bookmarks list."""

	if len(bk) > 0:

		ids, names = map(list,apply(zip,db.get_keywords(bk)))

		for key in exc:

			if key not in ids:

				ids.append(key)

				names.append(db.get_keyword(key))

		allkw = map(lambda x,y: [x, y], ids, names)

	else:

		allkw = db.get_all_keywords()

	(kw, cnt) = map(list,apply(zip, db.get_keywords_count(bk)))

	res = []

	for key in allkw:

		is_selected = key[0] in sel

		is_excluded = key[0] in exc

		is_unselected = not (is_selected or is_excluded)

		if key[0] in kw:

			kcnt = cnt[kw.index(key[0])]

		else:

			kcnt = 0

		res.append({'id':key[0],

			'keyword': key[1],

			'count' : kcnt,

			'selected' : is_selected,

			'excluded' : is_excluded,

			'unselected' : is_unselected})

	return res

def sort_keywords(kw, pref):

	global _sk_rev_fact

	global _sk_sort

	if pref['keywords_reverse']:

		_sk_rev_fact = -1

	else:

		_sk_rev_fact = 1

	_sk_sort = pref['keywords_sort'] 

	kw.sort(lambda l, r: _sk_rev_fact*cmp(l[_sk_sort], r[_sk_sort]))

	return kw