from __future__ import annotations
import hmac
import hashlib
import time
from typing import List, Dict, Any

class GovernanceLedger:
  def __init__(self, key: bytes = b"secret"):
    self.key = key
    self.entries: List[Dict[str, Any]] = []

  def sign(self, payload: Dict[str, Any]) -> str:
    m = hashlib.sha256()
    m.update(str(payload).encode())
    m.update(self.key)
    return m.hexdigest()

  def append_entry(self, action: str, details: Dict[str, Any]) -> Dict[str, Any]:
    entry = {
      "timestamp": time.time(),
      "action": action,
      "details": details,
    }
    entry["signature"] = self.sign(entry)
    self.entries.append(entry)
    return entry

  def get_entries(self) -> List[Dict[str, Any]]:
    return self.entries