"""Simple file-backed idempotency for dual-run commands."""

from __future__ import annotations

import hashlib
import json
import os
from pathlib import Path
from typing import Any


def _store_path() -> Path:
    raw = os.environ.get("RM_IDEMPOTENCY_PATH", "~/.repo-manager/idempotency.json")
    return Path(raw).expanduser()


def _load() -> dict[str, Any]:
    path = _store_path()
    if not path.is_file():
        return {}
    try:
        return json.loads(path.read_text(encoding="utf-8"))
    except (OSError, json.JSONDecodeError):
        return {}


def _save(data: dict[str, Any]) -> None:
    path = _store_path()
    path.parent.mkdir(parents=True, exist_ok=True)
    path.write_text(json.dumps(data, indent=2) + "\n", encoding="utf-8")


def payload_hash(payload: dict[str, Any]) -> str:
    blob = json.dumps(payload, sort_keys=True, default=str)
    return hashlib.sha256(blob.encode()).hexdigest()


def get(key: str) -> dict[str, Any] | None:
    return _load().get(key)


def put(key: str, payload_hash_value: str, result: dict[str, Any]) -> None:
    data = _load()
    data[key] = {"payload_hash": payload_hash_value, "result": result}
    _save(data)