# -*- coding: utf-8 -*-
"""
存储服务

提供文件上传/下载功能，支持 OSS 签名 URL 和 HTTP_REPLACE_MAP 环境变量。
"""

import os
import logging
import subprocess
from typing import Any, Dict, Optional, Tuple
from urllib.parse import unquote

import requests

logger = logging.getLogger(__name__)


# 文件扩展名到 Content-Type 的映射
_CONTENT_TYPE_MAP = {
    '.mp4': 'video/mp4',
    '.aac': 'audio/aac',
    '.ts': 'video/mp2t',
    '.m4a': 'audio/mp4',
}


def _get_content_type(file_path: str) -> str:
    """
    根据文件扩展名获取 Content-Type

    Args:
        file_path: 文件路径

    Returns:
        Content-Type 字符串
    """
    ext = os.path.splitext(file_path)[1].lower()
    return _CONTENT_TYPE_MAP.get(ext, 'application/octet-stream')


def _apply_http_replace_map(url: str) -> str:
    """
    应用 HTTP_REPLACE_MAP 环境变量替换 URL

    Args:
        url: 原始 URL

    Returns:
        替换后的 URL
    """
    replace_map = os.getenv("HTTP_REPLACE_MAP", "")
    if not replace_map:
        return url

    new_url = url
    replace_list = [i.split("|", 1) for i in replace_map.split(",") if "|" in i]
    for src, dst in replace_list:
        new_url = new_url.replace(src, dst)

    if new_url != url:
        logger.debug(f"HTTP_REPLACE_MAP: {url} -> {new_url}")

    return new_url


def upload_file(url: str, file_path: str, max_retries: int = 5, timeout: int = 60) -> bool:
    """兼容旧接口：仅返回上传是否成功。"""
    result, _ = upload_file_with_metrics(
        url=url,
        file_path=file_path,
        max_retries=max_retries,
        timeout=timeout,
    )
    return result


def upload_file_with_metrics(
    url: str,
    file_path: str,
    max_retries: int = 5,
    timeout: int = 60
) -> Tuple[bool, Dict[str, Any]]:
    """
    使用签名 URL 上传文件到 OSS

    Args:
        url: 签名 URL
        file_path: 本地文件路径
        max_retries: 最大重试次数
        timeout: 超时时间（秒）

    Returns:
        (是否成功, 上传指标)
    """
    metrics: Dict[str, Any] = {
        "upload_method": "none",
        "file_size_bytes": 0,
        "content_type": "",
        "http_attempts": 0,
        "http_retry_count": 0,
        "http_status_code": 0,
        "http_replace_applied": False,
        "rclone_attempted": False,
        "rclone_succeeded": False,
        "rclone_fallback_http": False,
        "error_type": "",
    }

    if not os.path.exists(file_path):
        logger.error(f"File not found: {file_path}")
        metrics["error_type"] = "file_not_found"
        return False, metrics

    file_size = os.path.getsize(file_path)
    metrics["file_size_bytes"] = file_size
    logger.info(f"Uploading: {file_path} ({file_size} bytes)")

    # 检查是否使用 rclone 上传
    if os.getenv("UPLOAD_METHOD") == "rclone":
        metrics["rclone_attempted"] = True
        logger.debug(f"Uploading to: {url}")
        result = _upload_with_rclone(url, file_path)
        metrics["rclone_succeeded"] = result
        if result:
            metrics["upload_method"] = "rclone"
            return True, metrics
        # rclone 失败时回退到 HTTP
        metrics["rclone_fallback_http"] = True

    # 应用 HTTP_REPLACE_MAP 替换 URL
    http_url = _apply_http_replace_map(url)
    metrics["http_replace_applied"] = http_url != url
    content_type = _get_content_type(file_path)
    metrics["content_type"] = content_type
    metrics["upload_method"] = "rclone_fallback_http" if metrics["rclone_fallback_http"] else "http"
    logger.debug(f"Uploading to: {http_url} (Content-Type: {content_type})")

    retries = 0
    while retries < max_retries:
        metrics["http_attempts"] = retries + 1
        try:
            with open(file_path, 'rb') as f:
                with requests.put(
                    http_url,
                    data=f,
                    stream=True,
                    timeout=timeout,
                    headers={"Content-Type": content_type}
                ) as response:
                    status_code = int(getattr(response, 'status_code', 0) or 0)
                    metrics["http_status_code"] = status_code
                    response.raise_for_status()
                    logger.info(f"Upload succeeded: {file_path}")
                    metrics["error_type"] = ""
                    return True, metrics

        except requests.exceptions.Timeout:
            retries += 1
            metrics["http_retry_count"] = retries
            metrics["error_type"] = "timeout"
            logger.warning(f"Upload timed out. Retrying {retries}/{max_retries}...")
        except requests.exceptions.RequestException as e:
            retries += 1
            metrics["http_retry_count"] = retries
            metrics["error_type"] = "request_exception"
            response_obj = getattr(e, 'response', None)
            status_code = getattr(response_obj, 'status_code', 0) if response_obj is not None else 0
            if isinstance(status_code, int) and status_code > 0:
                metrics["http_status_code"] = status_code
            logger.warning(f"Upload failed ({e}). Retrying {retries}/{max_retries}...")

    logger.error(f"Upload failed after {max_retries} retries: {file_path}")
    return False, metrics


def _upload_with_rclone(url: str, file_path: str) -> bool:
    """
    使用 rclone 上传文件

    Args:
        url: 目标 URL
        file_path: 本地文件路径

    Returns:
        是否成功
    """
    replace_map = os.getenv("RCLONE_REPLACE_MAP", "")
    if not replace_map:
        return False

    config_file = os.getenv("RCLONE_CONFIG_FILE", "")

    # 替换 URL
    new_url = url
    replace_list = [i.split("|", 1) for i in replace_map.split(",") if "|" in i]
    for src, dst in replace_list:
        new_url = new_url.replace(src, dst)
    new_url = new_url.split("?", 1)[0]  # 移除查询参数
    new_url = unquote(new_url)  # 解码 URL 编码的字符（如 %2F -> /）

    if new_url == url:
        return False

    if new_url.startswith(("http://", "https://")):
        logger.warning("rclone upload skipped: URL still starts with http after replace")
        logger.debug(f"rclone upload skipped address: {new_url}")
        return False

    cmd = [
        "rclone",
        "copyto",
        "--no-check-dest",
        "--ignore-existing",
        "--multi-thread-chunk-size",
        "8M",
        "--multi-thread-streams",
        "8",
    ]
    if config_file:
        cmd.extend(["--config", config_file])
    cmd.extend([file_path, new_url])

    logger.debug(f"rclone command: {' '.join(cmd)}")

    result = subprocess.run(cmd, capture_output=True, text=True)
    if result.returncode == 0:
        logger.info(f"rclone upload succeeded: {file_path}")
        return True

    stderr = (result.stderr or '').strip()
    stderr = stderr[:500] if stderr else ""
    logger.warning(f"rclone upload failed (code={result.returncode}): {file_path} {stderr}")
    return False


def download_file(
    url: str,
    file_path: str,
    max_retries: int = 5,
    timeout: int = 30,
    skip_if_exist: bool = False
) -> bool:
    """
    使用签名 URL 下载文件

    Args:
        url: 签名 URL
        file_path: 本地文件路径
        max_retries: 最大重试次数
        timeout: 超时时间（秒）
        skip_if_exist: 如果文件存在则跳过

    Returns:
        是否成功
    """
    # 如果文件已存在且跳过
    if skip_if_exist and os.path.exists(file_path):
        logger.debug(f"File exists, skipping download: {file_path}")
        return True

    logger.debug(f"Downloading: {url}")

    # 确保目标目录存在
    file_dir = os.path.dirname(file_path)
    if file_dir:
        os.makedirs(file_dir, exist_ok=True)

    # 应用 HTTP_REPLACE_MAP 替换 URL
    http_url = _apply_http_replace_map(url)

    retries = 0
    while retries < max_retries:
        try:
            with requests.get(http_url, timeout=timeout, stream=True) as response:
                response.raise_for_status()

                with open(file_path, 'wb') as f:
                    for chunk in response.iter_content(chunk_size=8192):
                        if chunk:
                            f.write(chunk)

            file_size = os.path.getsize(file_path)
            logger.info(f"Download succeeded: {file_path} ({file_size} bytes)")
            return True

        except requests.exceptions.Timeout:
            retries += 1
            logger.warning(f"Download timed out. Retrying {retries}/{max_retries}...")
        except requests.exceptions.RequestException as e:
            retries += 1
            logger.warning(f"Download failed ({e}). Retrying {retries}/{max_retries}...")

    logger.error(f"Download failed after {max_retries} retries")
    logger.debug(f"Download failed source address: {url}")
    return False