import { Database } from 'bun:sqlite';
import { mkdir } from 'node:fs/promises';
import { dirname } from 'node:path';
import { env } from './env.ts';

await mkdir(dirname(env.stateDbPath), { recursive: true });
const db = new Database(env.stateDbPath, { create: true });
db.exec(`
  CREATE TABLE IF NOT EXISTS users (
    user_id         TEXT PRIMARY KEY,
    created_at      INTEGER NOT NULL,
    provisioned_at  INTEGER,
    deleted_at      INTEGER
  );
  CREATE TABLE IF NOT EXISTS activity (
    user_id    TEXT PRIMARY KEY,
    last_used  INTEGER NOT NULL
  );
`);

const now = () => Date.now();

export const state = {
  recordCreate: (userId: string): void => {
    db.prepare(
      `INSERT INTO users (user_id, created_at) VALUES (?, ?)
       ON CONFLICT(user_id) DO UPDATE SET deleted_at = NULL`,
    ).run(userId, now());
  },

  markProvisioned: (userId: string): void => {
    db.prepare(`UPDATE users SET provisioned_at = ? WHERE user_id = ?`).run(now(), userId);
  },

  markDeleted: (userId: string): void => {
    db.prepare(`UPDATE users SET deleted_at = ? WHERE user_id = ?`).run(now(), userId);
    db.prepare(`DELETE FROM activity WHERE user_id = ?`).run(userId);
  },

  touch: (userId: string): void => {
    db.prepare(
      `INSERT INTO activity (user_id, last_used) VALUES (?, ?)
       ON CONFLICT(user_id) DO UPDATE SET last_used = excluded.last_used`,
    ).run(userId, now());
  },

  // 查找过期:最后使用时间距今 > timeoutMs
  findIdle: (timeoutMs: number): string[] => {
    const cutoff = now() - timeoutMs;
    return db
      .prepare(`SELECT user_id FROM activity WHERE last_used < ?`)
      .all(cutoff)
      .map((r: any) => r.user_id);
  },

  clearActivity: (userId: string): void => {
    db.prepare(`DELETE FROM activity WHERE user_id = ?`).run(userId);
  },
};