"""Structured audit log writer.

Every agent action — including recommended-but-not-taken — must be
written here before execution. This is the safety net.
"""
from __future__ import annotations

import json
import logging
from datetime import datetime, timezone
from pathlib import Path

from .models import CandidateIncident, RCAResult

logger = logging.getLogger(__name__)


class AuditLog:
    """Appends structured JSON records to the audit log file.

    Minimum fields per record: timestamp, trigger type, raw signals,
    SLM diagnosis, action recommended, action taken, operator response,
    outcome.
    """

    def __init__(self, log_path: Path) -> None:
        self.log_path = log_path

    def record_incident(self, incident: CandidateIncident) -> None:
        """Write a CandidateIncident trigger record."""
        raise NotImplementedError

    def record_rca(self, result: RCAResult) -> None:
        """Write an RCA analysis result record."""
        raise NotImplementedError

    def record_action(
        self,
        incident_id: str,
        action: str,
        taken: bool,
        operator_response: str = "",
    ) -> None:
        """Write an action record (taken or suppressed)."""
        raise NotImplementedError

    def _append(self, record: dict) -> None:
        """Append a JSON record to the log file, one record per line."""
        record.setdefault("timestamp", datetime.now(tz=timezone.utc).isoformat())
        with self.log_path.open("a") as f:
            f.write(json.dumps(record) + "\n")