# py.test-3 --log-cli-level=DEBUG -v -k test_share_income share.py

EXPENSE = 1

#
# For a given income, return a list of the members who will not be paid in full
# and how much will remain in their expense balance.
#
# See https://forum.hostea.org/t/decision-revenue-sharing-model/92
#
def share_income(income, members):
    if income <= 0:
        return members
    if income < len(members):
        share = 1
        count = income
    else:
        share = min(int(income / len(members)), min(members, key=lambda m: m[EXPENSE])[EXPENSE])
        count = len(members)
    remaining = []
    for i in range(count):
        m = members[i]
        m[EXPENSE] -= share
        if m[EXPENSE] > 0:
            remaining.append(m)
    remaining.extend(members[count:])
    return share_income(income - share * count, remaining)

def test_share_income():
    assert share_income(1, [['a', 1], ['b', 1]]) == [['b', 1]]
    assert share_income(5, [['a', 10], ['b', 2]]) == [['a', 7]]
    assert share_income(5, [['a', 2], ['b', 10], ['c', 1]]) == [['b', 8]]
    assert share_income(5, [['a', 2], ['b', 10], ['c', 1], ['d', 40]]) == [['b', 9], ['d', 39]]
    assert share_income(5, [['a', 2], ['b', 10], ['c', 1], ['d', 40], ['e', 3]]) == [['a', 1], ['b', 9], ['d', 39], ['e', 2]]
    assert share_income(5, [['a', 2], ['b', 10], ['c', 1], ['d', 40], ['e', 3], ['f', 1]]) == [['a', 1], ['b', 9], ['d', 39], ['e', 2], ['f', 1]]