const Koa = require("koa");
const Router = require("@koa/router");
const mysql = require("mysql2/promise");
const Redis = require("redis");
require("dotenv").config();

const app = new Koa();
const router = new Router();

// MySQL 连接
const pool = mysql.createPool({
  host: process.env.MYSQL_HOST,
  user: process.env.MYSQL_USER,
  password: process.env.MYSQL_PASSWORD,
  database: process.env.MYSQL_DATABASE,
  waitForConnections: true,
  connectionLimit: 10,
  queueLimit: 0,
});


// Redis 客户端
const redisClient = Redis.createClient({
  url: `redis://${process.env.REDIS_HOST || 'localhost'}:${process.env.REDIS_PORT || 6379}`,
});

redisClient.on("error", (err) => console.log("Redis Client Error", err));

// 连接 Redis
(async () => {
  await redisClient.connect();
})();

// 示例路由
router.get("/", async (ctx) => {
  ctx.body = "Welcome to Koa Docker Demo!";
});

// 读写 MySQL 数据的示例路由
router.get("/users", async (ctx) => {
  const [rows] = await pool.query("SELECT * FROM users");
  ctx.body = rows;
});

// 读写 Redis 数据的示例路由
router.get("/visits", async (ctx) => {
  let visits = await redisClient.get("visits");
  visits = parseInt(visits) || 0;
  await redisClient.set("visits", visits + 1);
  ctx.body = { visits: visits + 1 };
});

// 手动执行 SQL 脚本的路由，用于模拟初始化数据库
router.get("/init-db", async (ctx) => {
  try {
    const sqlScript = await fs.readFile(
      path.join(__dirname, "../mysql-init/init.sql"),
      "utf8"
    );
    await pool.query(sqlScript);
    ctx.body = { message: "Database initialized successfully" };
  } catch (error) {
    console.error("Error initializing database:", error);
    ctx.status = 500;
    ctx.body = { error: "Failed to initialize database" };
  }
});

app.use(router.routes()).use(router.allowedMethods());

const PORT = process.env.PORT || 3000;
app.listen(PORT, () => {
  console.log(`Server running on http://localhost:${PORT}`);
});