#!/usr/bin/env node
import { parseArgs } from 'node:util';
import { fileURLToPath } from 'node:url';
import { resolve, dirname } from 'node:path';
import { resolveConfigPath, loadConfig } from './config.js';
import { Logger } from './logger.js';
import { Daemon } from './daemon.js';
import { install, uninstall, status } from './launchd.js';

const USAGE = `Usage: gsd-daemon [options]

Options:
  --config <path>  Path to YAML config file (default: ~/.gsd/daemon.yaml)
  --verbose        Print log entries to stderr in addition to the log file
  --install        Install the launchd LaunchAgent (auto-starts on login)
  --uninstall      Uninstall the launchd LaunchAgent
  --status         Show launchd agent status (registered, PID, exit code)
  --help           Show this help message and exit
`;

async function main(): Promise<void> {
  const { values } = parseArgs({
    options: {
      config: { type: 'string', short: 'c' },
      verbose: { type: 'boolean', short: 'v', default: false },
      install: { type: 'boolean', default: false },
      uninstall: { type: 'boolean', default: false },
      status: { type: 'boolean', default: false },
      help: { type: 'boolean', short: 'h', default: false },
    },
    strict: true,
  });

  if (values.help) {
    process.stdout.write(USAGE);
    process.exit(0);
  }

  // --- launchd commands (dispatch before Daemon creation) ---

  if (values.install) {
    const configPath = resolveConfigPath(values.config);
    const thisFile = fileURLToPath(import.meta.url);
    const scriptPath = resolve(dirname(thisFile), 'cli.js');

    install({
      nodePath: process.execPath,
      scriptPath,
      configPath,
    });
    process.stdout.write('gsd-daemon: launchd agent installed and loaded.\n');
    process.exit(0);
  }

  if (values.uninstall) {
    uninstall();
    process.stdout.write('gsd-daemon: launchd agent uninstalled.\n');
    process.exit(0);
  }

  if (values.status) {
    const result = status();
    if (!result.registered) {
      process.stdout.write('gsd-daemon: not registered with launchd.\n');
    } else if (result.pid != null) {
      process.stdout.write(
        `gsd-daemon: running (PID ${result.pid}, last exit status: ${result.lastExitStatus ?? 'n/a'})\n`,
      );
    } else {
      process.stdout.write(
        `gsd-daemon: registered but not running (last exit status: ${result.lastExitStatus ?? 'n/a'})\n`,
      );
    }
    process.exit(0);
  }

  // --- normal daemon start ---

  const configPath = resolveConfigPath(values.config);
  const config = loadConfig(configPath);

  const logger = new Logger({
    filePath: config.log.file,
    level: config.log.level,
    verbose: values.verbose,
  });

  const daemon = new Daemon(config, logger);
  await daemon.start();
}

main().catch((err: unknown) => {
  const msg = err instanceof Error ? err.message : String(err);
  process.stderr.write(`gsd-daemon: fatal: ${msg}\n`);
  process.exit(1);
});