import fs from "node:fs/promises";
import os from "node:os";
import path from "node:path";

import type { FlightRunState } from "./types.js";

const DEFAULT_STATE_DIR = path.join(
  os.homedir(),
  ".openclaw",
  "workspace",
  "state",
  "flight-finder"
);

export function getFlightFinderStatePath(
  baseDir = DEFAULT_STATE_DIR
): string {
  return path.join(baseDir, "flight-finder-run.json");
}

export async function saveFlightFinderRunState(
  state: FlightRunState,
  baseDir = DEFAULT_STATE_DIR
): Promise<string> {
  await fs.mkdir(baseDir, { recursive: true });
  const statePath = getFlightFinderStatePath(baseDir);
  await fs.writeFile(statePath, JSON.stringify(state, null, 2));
  return statePath;
}

export async function loadFlightFinderRunState(
  baseDir = DEFAULT_STATE_DIR
): Promise<FlightRunState | null> {
  const statePath = getFlightFinderStatePath(baseDir);
  try {
    const raw = await fs.readFile(statePath, "utf8");
    return JSON.parse(raw) as FlightRunState;
  } catch (error) {
    const maybeNodeError = error as NodeJS.ErrnoException;
    if (maybeNodeError.code === "ENOENT") {
      return null;
    }
    throw error;
  }
}

export async function clearFlightFinderRunState(
  baseDir = DEFAULT_STATE_DIR
): Promise<void> {
  const statePath = getFlightFinderStatePath(baseDir);
  try {
    await fs.unlink(statePath);
  } catch (error) {
    const maybeNodeError = error as NodeJS.ErrnoException;
    if (maybeNodeError.code !== "ENOENT") {
      throw error;
    }
  }
}