import re
import os
import requests
import time

# 修改存储目录为 F:\测试
filename = r'F:\测试\音乐\\'

# 如果没有则创建文件夹
if not os.path.exists(filename):
    os.makedirs(filename)

# 请求网址
url = 'https://music.163.com/playlist?id=3778678'

# 伪造请求头
headers = {
    'user-agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/127.0.0.0 Safari/537.36'
}

# 发送请求
print("正在获取列表...")
response = requests.get(url, headers=headers)

# 提取数据
html_data = re.findall(r'<li><a href="/song\?id=(\d+)">(.*?)</a>', response.text)

# 限速设置：30mbps = 30 * 1024 * 1024 / 8 = 3932160 字节/秒
MAX_SPEED_BPS = 30 * 1024 * 1024 // 8  # 约3.75MB/s

# 下载
for i, (num_id, title) in enumerate(html_data, 1):
    try:
        # 方法1：替换所有Windows文件名中的非法字符
        # Windows文件名不能包含的字符: \ / : * ? " < > |
        clean_title = re.sub(r'[\\/*?:"<>|]', '', title)
        
        # 方法2：更严格的清理，只保留字母、数字、中文、空格和一些常用标点
        # clean_title = re.sub(r'[^a-zA-Z0-9\u4e00-\u9fa5\s\-_\(\)\[\]\.]', '', title)
        
        # 如果清理后文件名为空，使用歌曲ID作为文件名
        if not clean_title.strip():
            clean_title = f"song_{num_id}"
        
        # 检查文件是否已存在
        file_path = os.path.join(filename, clean_title + '.mp3')
        if os.path.exists(file_path):
            print(f"跳过已存在的文件: {clean_title}")
            continue
            
        print(f"正在下载 ({i}/{len(html_data)}): {clean_title} (原标题: {title})")
        
        # 调用接口
        music_url = f'https://music.163.com/song/media/outer/url?id={num_id}.mp3'
        
        # 发送请求获取响应（使用流模式）
        with requests.get(music_url, headers=headers, stream=True) as response:
            response.raise_for_status()
            
            # 获取文件大小
            total_size = int(response.headers.get('content-length', 0))
            
            # 保存文件
            start_time = time.time()
            downloaded_size = 0
            
            with open(file_path, 'wb') as f:
                for chunk in response.iter_content(chunk_size=8192):  # 8KB chunks
                    if chunk:
                        f.write(chunk)
                        downloaded_size += len(chunk)
                        
                        # 计算当前速度
                        elapsed_time = time.time() - start_time
                        if elapsed_time > 0:
                            current_speed = downloaded_size / elapsed_time  # 字节/秒
                            
                            # 如果速度超过限制，则等待
                            if current_speed > MAX_SPEED_BPS and downloaded_size < total_size:
                                expected_time = downloaded_size / MAX_SPEED_BPS
                                sleep_time = expected_time - elapsed_time
                                if sleep_time > 0:
                                    time.sleep(sleep_time)
                        
                        # 显示进度
                        if total_size > 0:
                            percent = downloaded_size / total_size * 100
                            print(f"\r进度: {percent:.1f}% ({downloaded_size//1024}KB/{total_size//1024}KB)", end='')
            
            print()  # 换行
            print(f"完成: {clean_title}")
            
    except Exception as e:
        print(f"下载失败 {title}: {str(e)}")
        # 如果下载失败，删除可能不完整的文件
        if 'file_path' in locals() and os.path.exists(file_path):
            os.remove(file_path)
    
    # 添加短暂延迟，避免请求过快
    time.sleep(0.5)

print("所有歌曲下载完成！")