MAX_PEOPLE_REQ_SIZE = 100

def split_seq(seq, size):
    """
    Split up the given sequence into pieces of the given size.

    Taken from http://code.activestate.com/recipes/425044/.
    """

    return [seq[i:i+size] for i in range(0, len(seq), size)]

class WhoisiCache(object):
    APP_NAME = "whoisi-cache"

    def __init__(self, server, storage, batch_size=MAX_PEOPLE_REQ_SIZE):
        self.server = server
        self.batch_size = batch_size
        self.people = storage

    def update(self):
        pid = self.server.get_max_person_id(app=self.APP_NAME)
        interval = range(len(self.people) + 1, pid + 1)
        if interval:
            subintervals = split_seq(interval, self.batch_size)
            for subinterval in subintervals:
                people = self.server.get_people(app=self.APP_NAME,
                                                first=subinterval[0],
                                                last=subinterval[-1])
                self.people.extend(people)