/*
 * 数据库初始化脚本
 * 自动创建数据库和表结构
 */
import postgres from "postgres";
import { readFileSync } from "fs";
import { join, dirname } from "path";

// 获取当前文件所在目录
const __dirname =
  typeof import.meta.dir !== "undefined"
    ? import.meta.dir
    : dirname(new URL(import.meta.url).pathname);

// 从环境变量获取数据库连接信息（不包含数据库名）
const getBaseConnection = () => {
  const user = process.env.DB_USER || "postgres";
  const password = process.env.DB_PASSWORD || "postgres";
  const host = process.env.DB_HOST || "localhost";
  const port = process.env.DB_PORT || "5432";
  return `postgresql://${user}:${password}@${host}:${port}`;
};

// 初始化数据库
export async function initDatabase() {
  const dbName = process.env.DB_NAME || "media";
  const baseUrl = getBaseConnection();

  try {
    // 连接到 PostgreSQL 服务器（使用默认的 postgres 数据库）
    const adminSql = postgres(`${baseUrl}/postgres`);

    // 检查数据库是否存在
    const dbExists = await adminSql`
      SELECT 1 FROM pg_database WHERE datname = ${dbName}
    `;

    // 如果数据库不存在，创建它
    if (dbExists.length === 0) {
      console.log(`Creating database: ${dbName}`);
      await adminSql.unsafe(`CREATE DATABASE ${dbName}`);
      console.log(`Database ${dbName} created successfully`);
    } else {
      console.log(`Database ${dbName} already exists`);
    }

    await adminSql.end();

    // 连接到新创建的数据库
    const sql = postgres(`${baseUrl}/${dbName}`);

    // 读取并执行 schema.sql
    const schemaPath = join(__dirname, "schema.sql");
    const schema = readFileSync(schemaPath, "utf-8");

    // 执行 schema 中的 SQL 语句
    console.log("Creating tables...");
    await sql.unsafe(schema);
    console.log("Tables created successfully");

    await sql.end();
    console.log("Database initialization completed");
  } catch (error: any) {
    console.error("Database initialization failed:", error.message);
    throw error;
  }
}

// 如果直接运行此文件，执行初始化
if (
  import.meta.main ||
  (typeof Bun !== "undefined" && Bun.main === import.meta.path)
) {
  initDatabase()
    .then(() => {
      console.log("Initialization complete");
      process.exit(0);
    })
    .catch((error) => {
      console.error("Initialization failed:", error);
      process.exit(1);
    });
}