import { readFileSync } from 'node:fs';
import { readFile } from 'node:fs/promises';
import { phpApi } from './api.mjs';
import { startRelay } from './relay.mjs';

/**
 * Starts the MCP relay (#429) from the environment. On stein2 it runs in the container
 * `feuerwerk-mcp` (tools/mcp/compose.yml), in CI beside the PHP server (tools/ci/serve.sh).
 *
 *   FEUERWERK_MCP_API          the API's index.php, as the relay reaches it
 *   FEUERWERK_MCP_KEY_FILE     the key both sides share (default data/mcp-relay.key)
 *   FEUERWERK_MCP_ORIGINS      the editor's origins, comma-separated
 *   FEUERWERK_MCP_PORT, _HOST  where to listen (8090 on all interfaces)
 *   FEUERWERK_MCP_TRUST_PROXY  1: the agent's address is nginx's X-Real-IP
 *   FEUERWERK_MCP_BACKEND      pass everything else on to this server (CI)
 */

const env = process.env;
const keyFile = env.FEUERWERK_MCP_KEY_FILE ?? new URL('../../data/mcp-relay.key', import.meta.url);
const key = readFileSync(keyFile, 'utf8').trim();
if (key.length < 32) throw new Error('The relay key has to be at least 32 characters');
if (!env.FEUERWERK_MCP_API) throw new Error('FEUERWERK_MCP_API is not set');
const origins = (env.FEUERWERK_MCP_ORIGINS ?? '')
  .split(',')
  .map((origin) => origin.trim())
  .filter(Boolean);
if (origins.length === 0) throw new Error('FEUERWERK_MCP_ORIGINS is not set');

// Read on every use: a deployment that brings new tools needs no restart of the relay.
const toolsFile = new URL('../../src/editor/agent/tools.json', import.meta.url);

const relay = await startRelay({
  port: Number(env.FEUERWERK_MCP_PORT ?? 8090),
  host: env.FEUERWERK_MCP_HOST ?? '0.0.0.0',
  api: phpApi(env.FEUERWERK_MCP_API, key),
  tools: async () => JSON.parse(await readFile(toolsFile, 'utf8')),
  origins,
  trustProxy: env.FEUERWERK_MCP_TRUST_PROXY === '1',
  backend: env.FEUERWERK_MCP_BACKEND || undefined,
  log: (line) => console.log(`${new Date().toISOString()} ${line}`),
});
console.log(`${new Date().toISOString()} relay on port ${relay.port} for ${origins.join(', ')}`);

for (const signal of ['SIGTERM', 'SIGINT']) {
  process.on(signal, () => void relay.close().then(() => process.exit(0)));
}