#!/usr/bin/env python3
"""
feishu_download.py — 从飞书消息中下载文件附件

用法：
    python3 feishu_download.py <message_id> [output_dir]

通过飞书 Open API 获取消息中的 file_key 并下载文件。
自动从 openclaw.json 读取 App ID / Secret 获取 token。
"""

import json, sys, os, requests, re

CONFIG_PATH = "/root/.openclaw/openclaw.json"
FEISHU_API  = "https://open.feishu.cn"

def get_feishu_creds():
    """从 openclaw 配置中提取飞书 App ID / Secret"""
    if not os.path.exists(CONFIG_PATH):
        print(f"ERROR: 找不到 {CONFIG_PATH}", file=sys.stderr)
        sys.exit(1)
    with open(CONFIG_PATH) as f:
        cfg = json.load(f)
    accounts = cfg.get("plugins", {}).get("entries", {}).get("feishu", {}).get("config", {}).get("accounts", {})
    default = accounts.get("default", {})
    app_id = default.get("appId", "")
    app_secret = default.get("appSecret", "")
    if not app_id or not app_secret:
        print("ERROR: 无法获取飞书 App ID / Secret", file=sys.stderr)
        sys.exit(1)
    return app_id, app_secret

def get_token(app_id, app_secret):
    """获取 tenant_access_token"""
    resp = requests.post(f"{FEISHU_API}/open-apis/auth/v3/tenant_access_token/internal",
                         json={"app_id": app_id, "app_secret": app_secret})
    data = resp.json()
    if data.get("code") != 0:
        print(f"ERROR: 获取 token 失败: {data}", file=sys.stderr)
        sys.exit(1)
    return data["tenant_access_token"]

def get_msg_body(message_id, token):
    """获取消息内容，提取 file_key 和文件名"""
    resp = requests.get(
        f"{FEISHU_API}/open-apis/im/v1/messages/{message_id}",
        headers={"Authorization": f"Bearer {token}"}
    )
    data = resp.json()
    if data.get("code") != 0:
        print(f"ERROR: 获取消息失败: {data}", file=sys.stderr)
        sys.exit(1)

    items = data.get("data", {}).get("items", [])
    if not items:
        print("ERROR: 消息为空", file=sys.stderr)
        sys.exit(1)

    body = items[0].get("body", {})
    content = json.loads(body.get("content", "{}"))
    msg_type = body.get("msg_type", "")
    file_key = content.get("file_key", "")
    file_name = content.get("file_name", f"file_{message_id}")

    if not file_key:
        print(f"ERROR: 消息类型 {msg_type}，没有 file_key", file=sys.stderr)
        print(f"  内容: {content}", file=sys.stderr)
        sys.exit(1)

    return file_key, file_name, msg_type

def download_file(message_id, file_key, token, output_path):
    """下载文件到指定路径"""
    url = f"{FEISHU_API}/open-apis/im/v1/messages/{message_id}/resources/{file_key}?type=file"
    resp = requests.get(url, headers={"Authorization": f"Bearer {token}"}, stream=True)
    if resp.status_code != 200:
        print(f"ERROR: 下载失败 (HTTP {resp.status_code}): {resp.text[:200]}", file=sys.stderr)
        sys.exit(1)

    with open(output_path, "wb") as f:
        for chunk in resp.iter_content(chunk_size=65536):
            if chunk:
                f.write(chunk)

    size = os.path.getsize(output_path)
    return size

def safe_filename(name):
    """清理文件名中的特殊字符"""
    name = name.strip()
    # 替换 Windows 不安全的字符
    name = re.sub(r'[<>:"/\\|?*]', '_', name)
    # 压缩多个空格/下划线
    name = re.sub(r'[_\s]+', '_', name)
    return name

def main():
    if len(sys.argv) < 2:
        print("用法: python3 feishu_download.py <message_id> [output_dir]", file=sys.stderr)
        print("示例: python3 feishu_download.py om_x100b6c16dd10b0acc243c1fa48b0695 /root/projects/uploads", file=sys.stderr)
        sys.exit(1)

    message_id = sys.argv[1]
    output_dir = sys.argv[2] if len(sys.argv) > 2 else "/root/projects/uploads"

    os.makedirs(output_dir, exist_ok=True)

    print(f"[1/4] 获取飞书凭证...")
    app_id, app_secret = get_feishu_creds()

    print(f"[2/4] 获取 token...")
    token = get_token(app_id, app_secret)

    print(f"[3/4] 获取消息 {message_id} 内容...")
    file_key, file_name, msg_type = get_msg_body(message_id, token)
    print(f"      → file_key: {file_key}")
    print(f"      → file_name: {file_name}")
    print(f"      → msg_type: {msg_type}")

    safe_name = safe_filename(file_name)
    output_path = os.path.join(output_dir, safe_name)

    print(f"[4/4] 下载文件到 {output_path}...")
    size = download_file(message_id, file_key, token, output_path)
    print(f"      ✅ 下载完成! 大小: {size/1024/1024:.1f} MB")
    print(f"      📁 {output_path}")

    # 输出结果信息（供调用方解析）
    result = {
        "status": "ok",
        "message_id": message_id,
        "file_key": file_key,
        "file_name": safe_name,
        "file_path": output_path,
        "file_size": size
    }
    print(f"\nJSON_OUTPUT:{json.dumps(result)}")

if __name__ == "__main__":
    main()