import '../../about/external/initial/SystemdSpec.dart';
import '../../about/internal/application/ServerProfile.dart';
import '../../about/internal/application/ServiceConfig.dart';
import '../../about/internal/application/StepTracker.dart';
import '../../comms/Comms.dart' show LogLine;
import '../parent/ParentViewModel.dart';
import 'ConnectSystemd.dart';

class ViewSystemd extends ParentViewModel {
  ConnectSystemd connection;

  ViewSystemd(super.context, this.connection);

  Stream<LogLine> get logs => getDataManager().logs;

  Stream<List<DeployStep>> get steps => getDataManager().stepStream;

  /// Writes the unit file, reloads systemd and (optionally) enables and starts
  /// it. On success the unit name is recorded against [service] so the deploy
  /// and log screens target the right unit from now on.
  void installUnit(
    ServerProfile server,
    SystemdSpec spec,
    ServiceConfig? service,
  ) async {
    if (!await canReach(server, () => installUnit(server, spec, service))) {
      return;
    }
    try {
      final result = await getDataManager().installSystemdUnit(
        server: server,
        unitName: spec.safeName,
        unitContent: spec.render(),
        enable: spec.enableOnBoot,
        startNow: spec.startNow,
      );

      if (result.ok && service != null) {
        service.serviceName = spec.safeName;
        await _persistService(server, service);
      }

      connection.onUnitInstalled(result);
    } catch (error) {
      handleError(
        error,
        () => installUnit(server, spec, service),
        () {},
        "Retry",
      );
    }
  }

  /// Saves the service back onto its server in storage.
  Future<void> _persistService(
    ServerProfile server,
    ServiceConfig service,
  ) async {
    final servers = await getDataManager().getServers();
    final serverIndex = servers.indexWhere((s) => s.id == server.id);
    if (serverIndex < 0) return;
    final services = servers[serverIndex].services;
    final serviceIndex = services.indexWhere((s) => s.id == service.id);
    if (serviceIndex < 0) return;
    services[serviceIndex] = service;
    await getDataManager().setServers(servers);
  }
}