import 'dart:io';

import 'package:dotenv/dotenv.dart';
import 'package:shelf/shelf.dart' show Middleware, Response;
import 'package:rra_backend/rra_backend.dart';
import 'package:shelf/shelf.dart';
import 'package:shelf/shelf_io.dart' as io;

Middleware _logger() => (handler) => (request) async {
  final sw = Stopwatch()..start();
  final response = await handler(request);
  sw.stop();
  final ms = sw.elapsedMilliseconds;
  print('${request.method} ${response.statusCode} ${ms}ms ${request.url.path}');
  return response;
};

Middleware _cors() => (handler) => (request) async {
  if (request.method == 'OPTIONS') {
    return Response.ok('', headers: _corsHeaders);
  }
  final response = await handler(request);
  return response.change(headers: _corsHeaders);
};

const _corsHeaders = {
  'Access-Control-Allow-Origin': '*',
  'Access-Control-Allow-Methods': 'GET, OPTIONS',
  'Access-Control-Allow-Headers': 'Origin, Content-Type',
};

void main() async {
  final env = DotEnv(includePlatformEnvironment: true)..load();

  final mapboxToken = env['MAPBOX_ACCESS_TOKEN'];
  if (mapboxToken == null || mapboxToken.isEmpty) {
    stderr.writeln('ERROR: MAPBOX_ACCESS_TOKEN not set');
    exit(1);
  }

  final port = int.tryParse(env['PORT'] ?? '8080') ?? 8080;

  await TileCache.init();

  final handler = const Pipeline()
      .addMiddleware(_logger())
      .addMiddleware(_cors())
      .addHandler(buildRouter(mapboxToken).call);

  final server = await io.serve(handler, InternetAddress.anyIPv4, port);
  print('rra_backend listening on :${server.port}');
}