"""
阿里云OSS工具类
用于Python脚本中上传/下载文件到OSS
"""
import os
import oss2
from datetime import datetime
from typing import Optional


class OSSUploader:
    """OSS上传工具"""
    
    def __init__(
        self,
        access_key_id: Optional[str] = None,
        access_key_secret: Optional[str] = None,
        bucket_name: Optional[str] = None,
        endpoint: Optional[str] = None
    ):
        """
        初始化OSS客户端
        
        Args:
            access_key_id: AccessKey ID（可选，默认从环境变量读取）
            access_key_secret: AccessKey Secret（可选，默认从环境变量读取）
            bucket_name: Bucket名称（可选，默认从环境变量读取）
            endpoint: OSS访问域名（可选，默认从环境变量读取）
        """
        # 使用提供的值或从环境变量读取
        self.access_key_id = access_key_id or os.getenv('OSS_TEST_ACCESS_KEY_ID', 'LTAI5tNesdhDH4ErqEUZmEg2')
        self.access_key_secret = access_key_secret or os.getenv('OSS_TEST_ACCESS_KEY_SECRET', 'xZn7WUkTW76TqOLTh01zZATnU6p3Tf')
        self.bucket_name = bucket_name or os.getenv('OSS_TEST_BUCKET', 'bxmkb-beijing')
        self.endpoint = endpoint or os.getenv('OSS_TEST_ENDPOINT', 'https://oss-cn-beijing.aliyuncs.com/')
        
        # 移除endpoint中的协议前缀（oss2库不需要https://）
        self.endpoint = self.endpoint.replace('https://', '').replace('http://', '')
        
        # 创建认证对象
        self.auth = oss2.Auth(self.access_key_id, self.access_key_secret)
        
        # 创建Bucket对象
        self.bucket = oss2.Bucket(self.auth, self.endpoint, self.bucket_name)
        
        # 基础路径
        self.base_path = "wht/"
        
    def upload_file(self, local_file_path: str, object_name: Optional[str] = None) -> str:
        """
        上传文件到OSS
        
        Args:
            local_file_path: 本地文件路径
            object_name: OSS对象名称（可选，默认自动生成）
            
        Returns:
            OSS文件的完整URL
        """
        # 如果未指定对象名称，自动生成
        if object_name is None:
            # 生成格式: wht/YYYYMMDD/timestamp_filename.ext
            now = datetime.now()
            date_dir = now.strftime("%Y%m%d")
            timestamp = int(now.timestamp())
            filename = os.path.basename(local_file_path)
            object_name = f"{self.base_path}{date_dir}/{timestamp}_{filename}"
        
        # 上传文件
        self.bucket.put_object_from_file(object_name, local_file_path)
        
        # 生成访问URL
        url = f"https://{self.bucket_name}.{self.endpoint}/{object_name}"
        
        return url
    
    def upload_bytes(self, data: bytes, filename: str) -> str:
        """
        上传字节数据到OSS
        
        Args:
            data: 文件字节数据
            filename: 文件名（用于生成扩展名）
            
        Returns:
            OSS文件的完整URL
        """
        # 生成对象名称
        now = datetime.now()
        date_dir = now.strftime("%Y%m%d")
        timestamp = int(now.timestamp())
        
        # 获取扩展名
        ext = os.path.splitext(filename)[1] or '.jpg'
        object_name = f"{self.base_path}{date_dir}/{timestamp}_{filename}"
        
        # 上传数据
        self.bucket.put_object(object_name, data)
        
        # 生成访问URL
        url = f"https://{self.bucket_name}.{self.endpoint}/{object_name}"
        
        return url
    
    def delete_file(self, file_url: str) -> bool:
        """
        从OSS删除文件
        
        Args:
            file_url: OSS文件的完整URL
            
        Returns:
            是否删除成功
        """
        try:
            # 从URL中提取对象名称
            # 格式: https://bucket.endpoint/path/file.jpg
            prefix = f"https://{self.bucket_name}.{self.endpoint}/"
            if file_url.startswith(prefix):
                object_name = file_url[len(prefix):]
                self.bucket.delete_object(object_name)
                return True
            else:
                return False
        except Exception as e:
            print(f"删除OSS文件失败: {e}")
            return False
    
    def file_exists(self, file_url: str) -> bool:
        """
        检查OSS文件是否存在
        
        Args:
            file_url: OSS文件的完整URL
            
        Returns:
            文件是否存在
        """
        try:
            prefix = f"https://{self.bucket_name}.{self.endpoint}/"
            if file_url.startswith(prefix):
                object_name = file_url[len(prefix):]
                return self.bucket.object_exists(object_name)
            else:
                return False
        except Exception:
            return False


# 创建默认实例（使用环境变量配置）
default_uploader = None

def get_oss_uploader() -> OSSUploader:
    """获取默认的OSS上传器实例"""
    global default_uploader
    if default_uploader is None:
        default_uploader = OSSUploader()
    return default_uploader