#!/usr/bin/env bun
/**
 * Orchestration script for running all example servers.
 *
 * Usage:
 *   bun examples/run-all.ts start  - Build and start all examples
 *   bun examples/run-all.ts dev    - Run all examples in dev/watch mode
 *   bun examples/run-all.ts build  - Build all examples
 *
 * Environment:
 *   EXAMPLE=<folder>  - Run only a single example (e.g., EXAMPLE=say-server)
 */

import { readdirSync, statSync, existsSync } from "fs";
import concurrently from "concurrently";

const BASE_PORT = 3101;
const BASIC_HOST = "basic-host";

// Optional: filter to a single example via EXAMPLE env var (folder name)
const EXAMPLE_FILTER = process.env.EXAMPLE;

// Find all example directories except basic-host that have a package.json,
// assign ports, and build URL list
const allServers = readdirSync("examples")
  .filter(
    (d) =>
      d !== BASIC_HOST &&
      statSync(`examples/${d}`).isDirectory() &&
      existsSync(`examples/${d}/package.json`),
  )
  .sort(); // Sort for consistent port assignment

// Filter servers if EXAMPLE is specified
const filteredDirs = EXAMPLE_FILTER
  ? allServers.filter((d) => d === EXAMPLE_FILTER)
  : allServers;

if (EXAMPLE_FILTER && filteredDirs.length === 0) {
  console.error(`Error: No example found matching EXAMPLE=${EXAMPLE_FILTER}`);
  console.error(`Available examples: ${allServers.join(", ")}`);
  process.exit(1);
}

const servers = filteredDirs.map((dir, i) => ({
  dir,
  port: BASE_PORT + i,
  url: `http://localhost:${BASE_PORT + i}/mcp`,
}));

const COMMANDS = ["start", "dev", "build"];

const command = process.argv[2];

if (!command || !COMMANDS.includes(command)) {
  console.error(`Usage: bun examples/run-all.ts <${COMMANDS.join("|")}>`);
  process.exit(1);
}

// Build the SERVERS environment variable (JSON array of URLs)
const serversEnv = JSON.stringify(servers.map((s) => s.url));

console.log(`Running command: ${command}`);
if (EXAMPLE_FILTER) {
  console.log(`Filtering to single example: ${EXAMPLE_FILTER}`);
}
console.log(
  `Server examples: ${servers.map((s) => `${s.dir}:${s.port}`).join(", ")}`,
);
console.log("");

// Build command list for concurrently
const commands: Parameters<typeof concurrently>[0] = [
  // Server examples
  ...servers.map(({ dir, port }) => ({
    command: `npm run --workspace examples/${dir} ${command}`,
    name: dir,
    env: { PORT: String(port) },
  })),
  // Basic host with SERVERS env
  {
    command: `npm run --workspace examples/${BASIC_HOST} ${command}`,
    name: BASIC_HOST,
    env: { SERVERS: serversEnv },
  },
];

// If dev mode, also run the main library watcher
if (command === "dev") {
  commands.unshift({
    command: "npm run watch",
    name: "lib",
  });
}

const { result } = concurrently(commands, {
  prefix: "name",
  // For build command, we want all to complete; for start/dev, kill all on failure
  killOthersOnFail: command !== "build",
});

result.catch(() => process.exit(1));