import requests
from bs4 import BeautifulSoup
import re
import urllib.parse

Cookie = '填自己的'

headers = {
    'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/78.0.3904.108 Safari/537.36',
    'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3',
    'Accept-Encoding':'gzip, deflate',
    'Connection': 'keep-alive',
    'Cookie': Cookie
}

def fetch(url):
    session = requests.Session()
    respone = session.get(
        url,
        headers=headers,
        allow_redirects=False
    )
    return respone

url_front = 'http://iclass.tku.edu.tw/api/uploads/'
url_end = '/blob?preview=true'
start = 0
def download(resp, file_name):
    filetype = file_name.split('.')[1]
    try:
        with open('./download/'+filetype+'/'+file_name, "wb") as file:
            file.write(resp.content)
    except (RuntimeError, TypeError, NameError, ValueError, KeyError, FileNotFoundError):
        with open('./download/other/'+file_name, "wb+") as file:
            file.write(resp.content)


for number in range(start, start+300000):
    resp = fetch(url_front+str(number)+url_end)
#    print(resp.status_code)
    if resp.status_code != 404:
        if resp.status_code == 302:
            try:
                url = resp.headers['Location']
                filename = urllib.parse.unquote(re.split(r"=", url)[-1])
                resp = fetch(url)
                download(resp, filename)
                print('[Success]', number, "file: "+filename)
            except:
                print('[Failed]', number)
        elif resp.status_code == 200:
            try:
                filename = str(number)+".png"
                download(resp, filename)
                print('[Success]', number, "file: "+filename)
            except:
                print('[Failed]', number)
    elif(number%500) == 0:
        print('[Failed]', number)