import Database from "better-sqlite3";

const db = new Database("db.sqlite");

// init DB
db.prepare(
  `CREATE TABLE IF NOT EXISTS time_ranges (
    id INTEGER PRIMARY KEY,
     name TEXT NOT NULL DEFAULT '',
     range TEXT NOT NULL DEFAULT '',
     username TEXT NOT NULL DEFAULT ''
  )`
).run();
db.prepare(
  `CREATE TABLE IF NOT EXISTS configs (
    name TEXT PRIMARY KEY,
    value TEXT NOT NULL
  )`
).run();
db.prepare(
  `INSERT OR IGNORE INTO configs (name, value) VALUES ('limit', '1')`
).run();
db.prepare(
  `INSERT OR IGNORE INTO configs (name, value) VALUES ('token', 'woshimima')`
).run();
db.prepare(
  `INSERT OR IGNORE INTO configs (name, value) VALUES ('started', 'false')`
).run();

// prepare statements
const insertTimeRange = db.prepare(
  `INSERT INTO time_ranges (name, range) VALUES (?, ?)`
);
const getTimeRanges = db.prepare(`SELECT * FROM time_ranges ORDER BY range, name`);
const deleteTimeRange = db.prepare(`DELETE FROM time_ranges WHERE id = ?`);
const update = db.prepare(
  `UPDATE time_ranges SET name = ?, range = ?, username = ? WHERE id = ?`
);
const updateUsername = db.prepare(
  `UPDATE time_ranges SET username = ? WHERE id = ?`
);

const countUser = db.prepare(
  `SELECT COUNT(*) as count FROM time_ranges WHERE username = ?`
);
const getUsername = db.prepare(`SELECT username FROM time_ranges WHERE id = ?`);
const updateUsernameWithLimit = db.transaction((username, id, limit) => {
  const count = countUser.get(username).count;
  const existingUsername = getUsername.get(id).username;
  if (!getStarted()) {
    throw new Error("还没到开始时间喔");
  }
  if (existingUsername !== "") {
    throw new Error("这个时间段已经有人了喔");
  }
  if (count >= limit) {
    throw new Error("达到数量上限啦");
  }
  updateUsername.run(username, id);
});

const getConfigStmt = db.prepare(`SELECT value FROM configs WHERE name = ?`);
const setConfigStmt = db.prepare(`UPDATE configs SET value = ? WHERE name = ?`);
const getLimit = () => {
  const limit = getConfigStmt.get("limit").value;
  return parseInt(limit);
};
const setLimit = (limit) => {
  setConfigStmt.run(limit, "limit");
};
const getToken = () => {
  const token = getConfigStmt.get("token").value;
  return token;
};

const authenticate = (token) => {
  const tokenFromDB = getToken();
  return token === tokenFromDB;
};

const getStarted = () => {
  const started = getConfigStmt.get("started").value;
  return started === "true";
};

const setStarted = (started) => {
  const started_string = started ? "true" : "false";
  setConfigStmt.run(started_string, "started");
};

export {
  insertTimeRange,
  getTimeRanges,
  deleteTimeRange,
  update,
  updateUsername,
  updateUsernameWithLimit,
  getLimit,
  setLimit,
  authenticate,
  getStarted,
  setStarted,
};