# -*- coding: utf-8 -*-
"""
Created on Sun Apr  5 11:58:25 2020

@author: 54861
"""

import requests
import math
import os
import re

headers = {
        #'Referer': start_url,  # 注意加上referer
        'User-Agent': 'Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.87 Safari/537.36'
    }

"""
获取总视频数
参数：albumID  专辑ID
"""
def get_album_number(albumID):
    url = "https://www.ximalaya.com/revision/album?albumId="+str(albumID)
    resp = requests.get(url,headers = headers)
    result = resp.json()
    if result['ret'] == 200:
        cover = result['data']['mainInfo']['cover']
        albumTitle = result['data']['mainInfo']['albumTitle']
        count = result['data']['tracksInfo']['trackTotalCount']
    else:
        cover=''
        albumTitle=''
        count = 0
    return cover,albumTitle,count
    
"""
获取一页音频信息
参数：albumID  专辑ID
参数：pageNum  ！！页码1开始！！
"""
def get_track_list(albumID, pageNum):
    trackList = []
    url = "https://www.ximalaya.com/revision/album/v1/getTracksList?albumId="+str(albumID)+"&pageNum="+str(pageNum)
    resp = requests.get(url,headers = headers)
    result = resp.json()
    if result['ret'] == 200:
        tracks = result['data']['tracks']
        for track in tracks:
            trackList.append({'trackId':track['trackId'],'title':track['title']})
    return trackList

"""
获取音频下载地址
参数：trackID  音频ID
"""
def get_track_url(trackID):
    url = "https://www.ximalaya.com/revision/play/v1/audio?id="+str(trackID)+"&ptype=1"
    resp = requests.get(url,headers = headers)
    result = resp.json()
    if result['ret'] == 200:
        src = result['data']['src']
        if len(src) > 0:
            return src
   
"""
下载音频
参数：url  音频下载地址
参数：file 文件本地路径
"""
def download_track(url,file):
    resp = requests.get(url, headers = headers, stream = True)
    with open(file, 'wb') as f:
        for data in resp.iter_content(chunk_size = 1024):
            if data: f.write(data)
 
"""
从一个字符串得到符合windows要求的文件名
"""    
def good_win_filename(title):
    rstr = r"[\/\\\:\*\?\"\<\>\|]" # '/ \ : * ? " < > |'
    new_title = re.sub(rstr, "_", title) # 替换为下划线
    return new_title
    
if __name__ == '__main__':
    
    albumId = 35958359
    coverUrl,albumTitle,total = get_album_number(albumId)
    dir = 'ximalaya_m4a/'
    if not os.path.exists(dir):#创建专辑文件夹
        os.makedirs(dir)
    dir = 'ximalaya_m4a/'+good_win_filename(albumTitle)+'/'
    if not os.path.exists(dir):#创建专辑文件夹
        os.makedirs(dir)
    download_track("http:"+coverUrl,dir+"cover"+coverUrl[coverUrl.rindex('.'):])#下载封面
    
    pageCount = math.ceil( total/30)
    i = 1
    for pageNum in range(pageCount):
        trackList = get_track_list(albumId,pageNum+1)
        for track in trackList:
            trackUrl = get_track_url(track['trackId'])
            if trackUrl:
                ext = trackUrl[trackUrl.rindex('.'):]
                file_path = dir + good_win_filename(track['title']) + ext
                print ('downloading file:'+str(i)+"of"+str(total)+', page '+str(pageNum+1)+"of"+str(pageCount)+"\n"+ trackUrl + "\n"+track['title'])
                download_track(trackUrl, file_path)
            i = i + 1
    print("\n\n"+str(i)+"files downed in:"+dir)