const express = require("express");
const http = require("http");
const path = require("path");
const fs = require("fs");
const os = require("os");
const pino = require("pino");

const { generateMusicPlan } = require("./lib/music/generator");
const { loadMeta, computeGenreProfiles } = require("./lib/training");

const logger = pino({ level: process.env.LOG_LEVEL || "info" });
const app = express();
const server = http.createServer(app);

const app = express();
app.use(express.json());

app.get("/health", (req, res) => {
  try {
    const meta = loadMeta();
    res.json({ ok: true, uptime: process.uptime(), training: { step: meta.step, loss: meta.loss } });
  } catch (err) {
    log.error({ err: err.message }, "health check failed");
    res.status(500).json({ ok: false, error: err.message });
  }
});

app.use(express.json({ limit: "1mb" }));
app.use((req, res, next) => {
  res.setHeader("Access-Control-Allow-Origin", "*");
  res.setHeader("Access-Control-Allow-Headers", "Content-Type");
  if (req.method === "OPTIONS") return res.sendStatus(200);
  next();
});

app.get("/health", (_req, res) => {
  res.json({ ok: true, uptime: process.uptime() });
});

app.get("/api/profiles", (_req, res) => {
  try {
    const profiles = computeGenreProfiles();
    res.json({ ok: true, profiles });
  } catch (error) {
    logger.error({ err: error }, "failed to compute profiles");
    res.status(500).json({ ok: false, error: "profile computation failed" });
  }
});

app.get("/api/status", (_req, res) => {
  try {
    const meta = loadMeta();
    res.json({ ok: true, meta });
  } catch (error) {
    logger.error({ err: error }, "failed to load status");
    res.status(500).json({ ok: false, error: "status read failed" });
  }
});

app.post("/api/generate", (req, res) => {
  const { genre, mood, duration, tempo, key, instruments } = req.body || {};
  const result = generateMusicPlan({ genre, mood, duration, tempo, key, instruments });
  if (!result.ok) {
    return res.status(400).json(result);
  }
  logger.info({
    genre: result.metadata.genre,
    mood: result.metadata.mood,
    tempo: result.metadata.tempo,
    duration: result.metadata.duration
  }, "generated composition plan");
  res.json(result);
});

const PUBLIC_DIR = path.join(__dirname, "public");
app.use(express.static(PUBLIC_DIR));

app.get("*", (_req, res) => {
  res.sendFile(path.join(PUBLIC_DIR, "index.html"));
});

server.listen(PORT, () => {
  const address = server.address();
  const port = typeof address === "object" && address ? address.port : PORT;
  logger.info({ port }, "narrow ai music engine online");
  fs.writeFileSync(path.join(os.homedir(), ".skynet_port"), String(port));
});