"""
@author: luojunhui
"""
import os
import re
import html
import cffi
import traceback

import requests
from uuid import uuid4
from fake_useragent import FakeUserAgent

from applications.utils.common import str_to_md5
from config import decrypt_key_path

headers = {
  'Content-Type': 'application/json',
  'User-Agent': FakeUserAgent().chrome
}


def extract_video_url_from_article(article_url):
    """
    :param article_url:
    :return:
    """
    response = requests.get(
        url=article_url,
        headers={'User-Agent': FakeUserAgent().random},
    )
    html_text = response.text
    w = re.search(
        r"mp_video_trans_info.*url:\s*\(\'(.*?)\'\)\.replace", html_text, re.S | re.M
    ).group(1)
    url = html.unescape(
        re.sub(
            r"\\x\d+", lambda x: bytes.fromhex(x.group().replace("\\x", "")).decode(), w
        )
    )
    return url


def download_gzh_video(article_url):
    """
    下载公众号视频
    :param article_url:
    :return:
    """
    try:
        video_url = extract_video_url_from_article(article_url)
    except Exception as e:
        return
    save_path = "static/{}.mp4".format(str_to_md5(video_url))
    headers = {
        'Accept': '*/*',
        'Accept-Language': 'zh,zh-CN;q=0.9',
        'Connection': 'keep-alive',
        'Origin': 'https://mp.weixin.qq.com',
        'Referer': 'https://mp.weixin.qq.com/',
        'Sec-Fetch-Dest': 'video',
        'Sec-Fetch-Mode': 'cors',
        'Sec-Fetch-Site': 'cross-site',
        'User-Agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/130.0.0.0 Safari/537.36',
        'sec-ch-ua': '"Chromium";v="130", "Google Chrome";v="130", "Not?A_Brand";v="99"',
        'sec-ch-ua-mobile': '?0',
        'sec-ch-ua-platform': '"macOS"'
    }
    res = requests.get(video_url, headers=headers)
    with open(save_path, "wb") as f:
        f.write(res.content)

    TEN_KB = 1024 * 10
    if os.path.getsize(save_path) > TEN_KB:
        return save_path
    else:
        return None


def download_sph_video(download_url, key):
    """
    download video, decrypt video and save to local
    """
    print("downloading video from {}".format(download_url))
    print("key is {}".format(key))
    file_id = uuid4().hex
    encrypted_path = f"static/encrypted_{file_id}.mp4"
    decrypted_path = f"static/decrypted_{file_id}.mp4"

    try:
        with requests.get(download_url, headers=headers, stream=True) as response:
            response.raise_for_status()

            with open(encrypted_path, 'wb') as f:
                for chunk in response.iter_content(chunk_size=8192):
                    if chunk:  # filter out keep-alive chunks
                        f.write(chunk)

        decrypt_sph_video(encrypted_path, key, decrypted_path)
        os.remove(encrypted_path)
        return decrypted_path

    except Exception as e:
        print(traceback.format_exc())
        for path in [encrypted_path, decrypted_path]:
            if os.path.exists(path):
                try:
                    os.remove(path)
                except OSError:
                    pass
        raise RuntimeError(f"Video processing failed: {str(e)}") from e


def decrypt_sph_video(video_path: str, key: int,  save_path: str) -> None:
    """
    Decrypt video file using C library.
    Args:
        video_path: Path to encrypted video file
        key: 32-bit unsigned integer decryption key
        save_path: Path to save decrypted video
    Raises:
        RuntimeError: If decryption fails
    """
    print("key is {}".format(key))
    ffi = cffi.FFI()

    try:
        lib = ffi.dlopen(decrypt_key_path)
        ffi.cdef('void decrypt(unsigned char *data, const size_t data_length, const uint32_t key);')

        with open(video_path, 'rb') as f:
            encrypted_data = f.read()

        c_data = ffi.new('unsigned char[]', list(encrypted_data))
        lib.decrypt(c_data, 2 ** 17, int(key))
        decrypted_data = bytes(ffi.buffer(c_data, len(encrypted_data))[:])

        with open(save_path, 'wb') as f:
            f.write(decrypted_data)

    except Exception as e:
        print(traceback.format_exc())
        raise RuntimeError(f"Decryption failed: {str(e)}") from e