import json
import requests
from requests.exceptions import RequestException
import re
import time

#爬取貓眼電影信息

def get_one_page(url):
		#增加了User-Agent識別，需要在headers中添加User-Agent參數。
    try:
        headers = {
            'User-Agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/65.0.3325.162 Safari/537.36'
        }
        response = requests.get(url, headers=headers)
        if response.status_code == 200:
            return response.text
        return None
    except RequestException:
        return None

	#正則提取
def parse_one_page(html):
    pattern = re.compile('
              

                .*?board-index.*?>(\d+).*?data-src="(.*?)".*?name">
                
                  (.*?)
                
                .*?star">(.*?)
                

                
                .*?releasetime">(.*?)
                

                
                '
                         + '.*?integer">(.*?).*?fraction">(.*?).*?
              
              ', re.S)
    items = re.findall(pattern, html)
	#遍歷提取結果并生成字典
    for item in items:
        yield {
            'index': item[0],
            'image': item[1],
            'title': item[2],
            'actor': item[3].strip()[3:],
            'time': item[4].strip()[5:],
            'score': item[5] + item[6]
        }

	#寫入文件
def write_to_file(content):
    with open('result.txt', 'a', encoding='utf-8') as f:
        f.write(json.dumps(content, ensure_ascii=False) + '\n')


def main(offset):
    url = 'http://maoyan.com/board/4?offset=' + str(offset)
    html = get_one_page(url)
    for item in parse_one_page(html):
        print(item)
        write_to_file(item)

	#分頁爬取
if __name__ == '__main__':
    for i in range(10):
        main(offset=i * 10)
		#延時等待
        time.sleep(1)