import signal
import argparse
import json
import pymongo
from queue import Queue
from threading import Thread
from urllib.request import urlopen

# 读取配置文件中的数据库参数
with open("config.json", "r") as f:
    config = json.load(f)
db_url = config["db_url"]
db_name = config["db_name"]
db_collection = config["db_collection"]

# 连接数据库，创建 papers 集合
client = pymongo.MongoClient(db_url)
db = client[db_name]
papers = db[db_collection]
papers_data = db['{}_data'.format(db_collection)]


def read_file(filename):
    data_list = []
    with open(filename, 'r') as f:
        for line in f:
            line_dict = json.loads(line)
            data_list.append(line_dict)
        # 在这里可以对每个字典对象进行操作，例如：
        # print(data_dict['key'])
    return data_list


def add_paper(file_path):
    papers.create_index("corpusid", unique=True)
    # 读取 paper 文件，存入数据库
    data_list = read_file(file_path)
    # 批量插入数据
    inserted_ids = 0

    try:
        result = papers.insert_many(data_list, ordered=False)
        inserted_ids = len(result.inserted_ids)
    except pymongo.errors.BulkWriteError as e:
        inserted_ids = e.details['nInserted']
    finally:
        # 输出插入结果
        print("总插入数据: {0}, 已插入数据: {1}, 已存在数据: {2}" .format(
            len(data_list), inserted_ids, papers.count_documents({})))


def crawl_data():
    papers_data.create_index("corpusid", unique=True)

    # 创建任务队列和线程
    q = Queue()
    num_threads = 4
    threads = []
    for i in range(num_threads):
        t = Thread(target=worker, args=(q,))
        t.daemon = True
        t.start()
        print("starting worker: {}".format(t.native_id))
        threads.append(t)

    # 从数据库中读取 URL，加入任务队列
    for data in papers.find():
        if 'consumed' in data.keys() and data['consumed'] is True:
            continue
        # print(data['corpusid'])
        # print(data['url'])
        url = data["url"]
        corpusid = data["corpusid"]
        q.put((url, corpusid))
        break

    #
    print("Waitting for the task queue to complete...")
    q.join()
    print("The task queue has been completed!")

    # 停止线程
    for i in range(num_threads):
        q.put(None)
    for t in threads:
        print("stoping worker: {}" . format(t.native_id))
        t.join()


def mark_data_as_consumed(id):
    papers.update_one({'_id': id}, {'$set': {'consumed': True}})


def worker(q):
    while True:
        item = q.get()
        if item is None:
            break
        print('crawling data: {}'.format(item[0]))
        try:
            data = fetch_data(item[0])
            data = {
                'url': item[0],
                'corpusid': item[1]
            }
            if data is not None:
                papers_data.insert_one(data)
                mark_data_as_consumed(item[1])
        except Exception as error:
            # handle the exception
            print("An exception occurred:", error)
        finally:
            q.task_done()


def fetch_data(url):
    response = urlopen(url)
    # time.sleep(5)
    data = None
    # data = json.load(response)
    return data if isinstance(data, dict) else None


def onSigInt(signo, frame):
    pass


if __name__ == "__main__":
    # 主进程退出信号
    signal.signal(signal.SIGINT, onSigInt)

    parser = argparse.ArgumentParser(description="Crawl data from URLs")
    parser.add_argument(
        "command", choices=["add_paper", "crawl_data"], help="Command to execute"
    )
    parser.add_argument("--path", help="Path to add to papers")
    args = parser.parse_args()

    if args.command == "add_paper":
        add_paper(args.path)
    elif args.command == "crawl_data":
        crawl_data()