import { spawn } from "node:child_process";
import net from "node:net";

const commands = [
  {
    name: "service",
    command: "node",
    args: ["service/src/server.js"],
    port: 4317
  },
  {
    name: "web",
    command: "npm.cmd",
    args: ["run", "web:dev"],
    port: 5173
  }
];

const occupied = [];
for (const command of commands) {
  if (await isPortInUse(command.port)) {
    occupied.push(command);
  }
}

if (occupied.length > 0) {
  for (const command of occupied) {
    console.error(`[dev] port ${command.port} is already in use; not starting ${command.name}.`);
  }
  console.error("[dev] stop the old process first, then run npm.cmd run dev again.");
  process.exit(1);
}

const children = commands.map(({ name, command, args }) => {
  const child = spawn(command, args, {
    cwd: process.cwd(),
    stdio: ["ignore", "pipe", "pipe"],
    shell: false
  });

  child.stdout.on("data", (data) => writePrefixed(name, data));
  child.stderr.on("data", (data) => writePrefixed(name, data));
  child.on("exit", (code) => {
    if (code !== 0 && code !== null) {
      console.error(`[${name}] exited with code ${code}`);
    }
  });

  return child;
});

for (const signal of ["SIGINT", "SIGTERM"]) {
  process.on(signal, () => {
    for (const child of children) {
      child.kill(signal);
    }
    process.exit(0);
  });
}

function writePrefixed(name, data) {
  const lines = data.toString().split(/\r?\n/).filter(Boolean);
  for (const line of lines) {
    console.log(`[${name}] ${line}`);
  }
}

function isPortInUse(port) {
  return new Promise((resolve) => {
    const server = net.createServer();

    server.once("error", () => resolve(true));
    server.once("listening", () => {
      server.close(() => resolve(false));
    });
    server.listen(port, "127.0.0.1");
  });
}