/// Command-line entry point: resolve CEPs from a terminal.
///
/// ```sh
/// dart run cepis 01001000
/// dart run cepis --base-url http://localhost:8080 01001000 20040020
/// ```
library;

import 'dart:convert';
import 'dart:io';

import 'package:cepis/cepis.dart';

const String _usage = '''
usage: cepis [--base-url URL] [--health] [CEP...]

  --base-url URL  where the API lives (default $defaultBaseUrl)
  --health        report the API's health instead of looking anything up
  -h, --help      show this message

One CEP prints the full record, coordinate included. Several go through the
batch endpoint, which carries no coordinate.''';

Future<int> run(List<String> arguments) async {
  var baseUrl = defaultBaseUrl;
  var wantHealth = false;
  final ceps = <String>[];

  for (var i = 0; i < arguments.length; i++) {
    final argument = arguments[i];
    if (argument == '-h' || argument == '--help') {
      stdout.writeln(_usage);
      return 0;
    } else if (argument == '--health') {
      wantHealth = true;
    } else if (argument == '--base-url') {
      if (i + 1 >= arguments.length) {
        stderr.writeln('cepis: --base-url needs a value');
        return 2;
      }
      baseUrl = arguments[++i];
    } else if (argument.startsWith('-')) {
      stderr.writeln('cepis: unknown option $argument');
      return 2;
    } else {
      ceps.add(argument);
    }
  }

  if (!wantHealth && ceps.isEmpty) {
    stderr.writeln(_usage);
    return 2;
  }

  final client = Client(baseUrl: baseUrl);
  try {
    if (wantHealth) {
      final report = await client.health();
      stdout.writeln(_encode(report.raw));
      return report.ok ? 0 : 1;
    }

    if (ceps.length == 1) {
      final address = await client.lookup(ceps.single);
      stdout.writeln(_encode(address.raw));
      return 0;
    }

    final result = await client.lookupMany(ceps);
    for (var i = 0; i < ceps.length; i++) {
      final address = result[i];
      stdout.writeln(
        address == null
            ? '${ceps[i]}\tnot found'
            : '${ceps[i]}\t${address.logradouro}\t${address.localidade}\t'
                '${address.uf}',
      );
    }
    return 0;
  } on CepisException catch (error) {
    stderr.writeln('cepis: ${error.message}');
    return 1;
  } finally {
    client.close();
  }
}

String _encode(Map<String, dynamic> data) =>
    const JsonEncoder.withIndent('  ').convert(data);

Future<void> main(List<String> arguments) async {
  exitCode = await run(arguments);
}