import fs from 'node:fs';
import path from 'node:path';
import { fileURLToPath } from 'node:url';
import mysql from 'mysql2/promise';

const __dirname = path.dirname(fileURLToPath(import.meta.url));

export function isUmsDatabaseConfigured() {
  return Boolean(
    process.env.UMS_DATABASE_URL ||
      (process.env.UMS_MYSQL_HOST && process.env.UMS_MYSQL_DATABASE),
  );
}

function poolOptions() {
  return {
    waitForConnections: true,
    connectionLimit: Math.max(1, Number(process.env.UMS_MYSQL_POOL_SIZE ?? 10)),
    queueLimit: 0,
    timezone: 'Z',
  };
}

export function createUmsPool() {
  if (!isUmsDatabaseConfigured()) {
    throw new Error('UMS MySQL 未配置，请设置 UMS_DATABASE_URL 或 UMS_MYSQL_*');
  }
  if (process.env.UMS_DATABASE_URL) {
    return mysql.createPool({ uri: process.env.UMS_DATABASE_URL, ...poolOptions() });
  }
  return mysql.createPool({
    host: process.env.UMS_MYSQL_HOST ?? 'localhost',
    port: Number(process.env.UMS_MYSQL_PORT ?? 3306),
    user: process.env.UMS_MYSQL_USER ?? 'boot',
    password: process.env.UMS_MYSQL_PASSWORD ?? '',
    database: process.env.UMS_MYSQL_DATABASE ?? 'memind_user_model',
    ...poolOptions(),
  });
}

export async function runUmsSchema(pool) {
  const schemaPath = path.join(__dirname, '..', 'schemas', 'memind_user_model-v0.sql');
  const sql = fs.readFileSync(schemaPath, 'utf8');
  const statements = sql
    .split(';')
    .map((statement) =>
      statement
        .split('\n')
        .filter((line) => !line.trim().startsWith('--'))
        .join('\n')
        .trim(),
    )
    .filter(Boolean);
  for (const statement of statements) {
    await pool.query(statement);
  }
}