import json
import time
import hmac
import secrets
import hashlib
from typing import Dict, Any

def generate_signed_headers(app_id: str, app_secret: str, data: Dict[str, Any], method: str = "POST") -> Dict[str, str]:
    timestamp = str(int(time.time() * 1000))
    nonce = secrets.token_hex(16)
    
    payload_str = json.dumps(data, ensure_ascii=False)
    payload_bytes = payload_str.encode("utf-8")
    actual_body_hash = hashlib.sha256(payload_bytes).hexdigest()

    string_to_sign = "\n".join([
        method.upper(),
        app_id,
        timestamp,
        nonce,
        actual_body_hash
    ])

    signature = hmac.new(
        app_secret.encode("utf-8"),
        string_to_sign.encode("utf-8"),
        hashlib.sha256
    ).hexdigest()

    headers = {
        "X-Ca-Appid": app_id,
        "X-Ca-Timestamp": timestamp,
        "X-Ca-Nonce": nonce,
        "X-Ca-Signature": signature,
        "Content-Type": "application/json; charset=utf-8"
    }
    
    return headers