import 'dart:io';

import 'package:podman/podman.dart';

Future<void> main(List<String> args) async {
  if (args.isEmpty || args.contains('--help') || args.contains('-h')) {
    _printUsage();
    return;
  }

  final flags = args
      .where((arg) => arg.startsWith('--'))
      .toList(growable: false);
  final positional = args
      .where((arg) => !arg.startsWith('--'))
      .toList(growable: false);

  if (positional.length < 2) {
    stderr.writeln('Provide a manifest name and at least one image reference.');
    _printUsage();
    exitCode = 64;
    return;
  }

  final manifestName = positional.first;
  final images = positional.sublist(1);
  final pushDestination = _readOption(flags, 'push');
  final cleanup = flags.contains('--cleanup');
  final amend = flags.contains('--amend');

  final annotations = _readKeyValueOptions(flags, 'annotation');
  if (annotations.isEmpty) {
    annotations['org.opencontainers.image.title'] = manifestName;
  }

  final client = PodmanClient();
  try {
    final created = await client.createManifest(
      manifestName,
      options: ManifestCreateOptions(
        images: images,
        all: true,
        amend: amend,
        annotations: annotations,
      ),
    );
    print('Created/updated manifest "$manifestName" (${created.id}).');

    final exists = await client.manifestExists(manifestName);
    print('Manifest exists: $exists');

    final details = await client.inspectManifest(manifestName);
    print('Schema version: ${details.schemaVersion}');
    print('Media type: ${details.mediaType}');
    print('Embedded manifests: ${details.manifests.length}');

    if (pushDestination != null && pushDestination.isNotEmpty) {
      final pushed = await client.pushManifest(manifestName, pushDestination);
      print('Pushed to $pushDestination (${pushed.id}).');
    }

    if (cleanup) {
      final result = await client.deleteManifest(
        manifestName,
        ignoreMissing: true,
      );
      print(
        'Deleted entries: ${result.deleted.length}; untagged: ${result.untagged.length}',
      );
    }
  } finally {
    await client.close();
  }
}

String? _readOption(List<String> args, String name) {
  final prefix = '--$name=';
  for (final arg in args) {
    if (arg.startsWith(prefix)) {
      return arg.substring(prefix.length);
    }
  }
  return null;
}

Map<String, String> _readKeyValueOptions(List<String> args, String name) {
  final prefix = '--$name=';
  final output = <String, String>{};

  for (final arg in args) {
    if (!arg.startsWith(prefix)) {
      continue;
    }

    final raw = arg.substring(prefix.length);
    final index = raw.indexOf('=');
    if (index <= 0 || index == raw.length - 1) {
      continue;
    }

    final key = raw.substring(0, index);
    final value = raw.substring(index + 1);
    output[key] = value;
  }

  return output;
}

void _printUsage() {
  print('''
Manifest workflow example

Usage:
  dart run example/manifest_workflow_example.dart <manifest-name> <image> [image ...] [options]

Examples:
  dart run example/manifest_workflow_example.dart groupware-stack
    quay.io/groupware/api:amd64 quay.io/groupware/api:arm64 --push=quay.io/groupware/api:latest

Options:
  --annotation=<k=v>        Add top-level annotation (repeatable)
  --push=<destination>      Push manifest to destination reference
  --amend                   Amend if manifest already exists
  --cleanup                 Delete manifest at end of run
  --help, -h                Show this help
''');
}