游戏中的定时刷新实现方式

情景1：现在有一个道具商店，共有10个道具可购买。玩家可使用某道具或钻石刷新道具商店中的道具，或者系统会每隔2小时赠送一次刷新次数。

问题1：如何实现间隔2小时实时刷新？

from datetime import datetime

def cal_count(timestamp):
    now_dt  = datetime.now()
    base_dt = datetime.fromtimestamp(0)
    last_dt   = datetime.fromtimestamp(timestamp)
 
    count = ((now_dt.date() - base_dt.date()).days*12 + now_dt.hour/2) - 
            ((last_dt.date() - base_dt.date()).days*12 + last_dt.hour/2)

    return count

if __name__ == "__main__":
    last_ts = 1433000132
    print cal_count(last_ts)

问题2：刷新后，如何随机出新的10个道具？ （注：items=[10001, 10002, 10003, ...], 对应的weight=[1, 2, 3, ...]）

import random
import time
import sys


def func1(items, weight, times):
    total_weight = sum(weight)
    rand_items   = {}
    all_items    = dict(zip(items, weight))
    for _idx in range(0, times):
        count = 0
        rand  = random.randint(0, total_weight-1)
        for _item, _weight in all_items.iteritems():
            count += _weight
            if rand < count:
                rand_items[(_item, _weight)] = rand_items.setdefault((_item, _weight), 0) + 1
                break

    return rand_items

def func2(items, weight, times):
    '''
    len(items) == len(weight)
    '''
    _now = time.time()
    if not items:
        return

    rand_pools   = []
    rand_items   = {}
    total_weight = sum(weight)

    for _idx, _item in enumerate(items):
        rand_pools.extend([_item]*weight[_idx])

    for _idx in range(0, times):
        item = random.choice(rand_pools)
        key  = (item, weight[items.index(item)])
        rand_items[key] = rand_items.setdefault(key, 0) + 1

    return rand_items


def pprint(args, debug=False):
    if debug:
        print args

if __name__ == "__main__": 
    debug  = True
    times  = 10 # rand times
    items  = range(1001, 2001)
    weight = range(100, 100100, 100)
    if len(items) != len(weight):
        pprint( 'data error.', debug )
        sys.exit()
 
    pprint( '
total items:%s, random times: %s.'%(len(items), times), debug )

    _now = time.time()
    rand_items = func1(items, weight, times)
    pprint( "
func 1 total cost %s seconds."%(time.time()-_now), debug )
    pprint( '
result:%s.' % sorted(rand_items.iteritems(), key=lambda dt:dt[0], reverse=True) )

    _now = time.time()
    rand_items = func2(items, weight, times)
    pprint( "
func 2 total cost %s seconds."%(time.time()-_now), debug )
    pprint( '
result:%s'% sorted(rand_items.iteritems(), key=lambda dt:dt[1], reverse=True) )