import requests
from bs4 import BeautifulSoup
# 反爬
headers = {
  'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, \
  like Gecko) Chrome/70.0.3538.102 Safari/537.36'
}

# 獲得請求
def open_url(url):
  response = requests.get(url, headers=headers)
  response.encoding = response.apparent_encoding
  html = response.text
  return html

# 提取標題
def get_title(url):
  soup = BeautifulSoup(url, 'lxml')
  title_tag = soup.find('dd')
  title = '\n' + title_tag.h1.get_text() + '\n'
  return title

# 提取文本
def get_texts(url):
  soup2 = BeautifulSoup(url, 'lxml')
  text_tags = soup2.find_all('dd', id="contents")
  return text_tags

# 保存標題
def save_title(filename, title):
  with open(filename, 'a+', encoding='utf-8') as file:
    file.write(title)

# 保存文本
def save_text(filename, text):
  with open(filename, 'a+', encoding='utf-8') as file:
    file.write(text)

# 主程序函數
def main():
  num = input('《純陽劍尊》你想要下載第幾章？（1-802）')
  num = int(num)
  number = 8184027 + num
  url = 'https://www.23us.so/files/article/html/15/15905/' + str(number) + '.html'
  filename = '純陽劍尊.txt'
  r = open_url(url)
  title = get_title(r)
  tags = get_texts(r)
  save_title(filename, title)
  for text_tag in tags:
    text = text_tag.get_text() + '\n'
    save_text(filename, text)
  print('第{}章已經下載完成！'.format(num))

if __name__ == '__main__':
  main()