# -*- coding: utf-8 -*-
# @Time : 2021/12/29 13:48
# @Author : XuJiakai
# @File : MongoDbFastScan
# @Software: PyCharm
import threading

import math
from log import get_log

log = get_log('MongoDbFastScan')


class MongoDbFastScan:
    def __init__(self, db):
        self.collection_name = None
        self.batch_size = 500
        self.thread_num = 1
        self.data_num = None
        self.db = db
        self.func = None

    def __start_thread(self, skip, limit):
        db = self.db
        skip = int(skip)
        limit = int(limit)
        li = []
        for i in db.get_collection(self.collection_name).find(no_cursor_timeout=True).skip(skip).limit(
                limit).batch_size(self.batch_size):
            li.append(i)
            if len(li) >= self.batch_size:
                log.info("start:{} end:{} handle ...".format(skip, skip + limit))
                self.func(li)
                li = []
            pass
        if len(li) != 0:
            log.info("start:{} end:{} handle ...".format(skip, skip + limit))
            self.func(li)
            pass
        log.info("start:{} end:{} success".format(skip, skip + limit))
        pass

    def scan(self, collection_name, func, thread_num=1, batch_size=500, skip=0):
        self.collection_name = collection_name
        self.func = func
        db = self.db
        count = db.get_collection(collection_name).count_documents(filter={})
        if count == 0:
            return
        self.data_num = math.ceil(count / thread_num) * thread_num
        log.info("data number: {} thread num: {}".format(self.data_num, self.thread_num))
        self.thread_num = thread_num
        self.batch_size = batch_size
        skip_value = skip % (self.data_num / thread_num)
        skip_continue = skip / (self.data_num / thread_num)

        for i in range(thread_num):
            if i < skip_continue:
                continue
            else:
                ttt = threading.Thread(target=self.__start_thread, args=(
                    i * (self.data_num / thread_num) + skip_value, self.data_num / thread_num - skip_value))
                ttt.start()
                pass
            pass

        pass


if __name__ == '__main__':
    m = MongoDbFastScan(None)


    def func(li):
        print(len(li))
        pass


    m.scan("a_xjk_recleanup_hk_20211221", func, thread_num=5)
    pass