const express = require("express");
const { createClient } = require("redis");

const PORT = process.env.PORT || 3000;
const REDIS_HOST = process.env.REDIS_HOST || "127.0.0.1";
const REDIS_PORT = parseInt(process.env.REDIS_PORT || "6379");
const REDIS_PASS = process.env.REDIS_PASS || undefined;

const app = express();
app.use(express.static("public"));

const redis = createClient({
  socket: { host: REDIS_HOST, port: REDIS_PORT },
  password: REDIS_PASS,
});

redis.on("error", (err) => console.error("Redis error:", err.message));

async function start() {
  await redis.connect();
  console.log("Redis connected");

  // API: latest sensor values
  app.get("/api/latest", async (req, res) => {
    try {
      const data = await redis.hGetAll("iot:latest");
      const items = Object.entries(data).map(([id, json]) => ({
        sensor_id: id,
        ...JSON.parse(json),
      }));
      res.json(items);
    } catch (e) {
      res.json({ error: e.message });
    }
  });

  // API: counters by device type
  app.get("/api/counters", async (req, res) => {
    try {
      const data = await redis.hGetAll("iot:counters");
      res.json(data);
    } catch (e) {
      res.json({ error: e.message });
    }
  });

  // API: recent events
  app.get("/api/recent", async (req, res) => {
    try {
      const items = await redis.zRange("iot:recent", 0, 49, { REV: true });
      res.json(items.map(JSON.parse));
    } catch (e) {
      res.json({ error: e.message });
    }
  });

  // Health check
  app.get("/", (req, res) => {
    res.send("IoT Dashboard OK");
  });

  app.listen(PORT, () => console.log(`Dashboard on port ${PORT}`));
}

start();