import 'package:equatable/equatable.dart';

/// The two moments this terminal talks to the server.
enum SyncEventType {
  catalogueImport('Catalogue Import', 'Pulled products from the server'),
  shiftReport('Shift Report', 'Pushed the day\'s takings to the server');

  const SyncEventType(this.label, this.description);

  final String label;
  final String description;

  bool get isInbound => this == SyncEventType.catalogueImport;
}

enum SyncStatus {
  /// Held locally, not yet sent. Nothing is ever discarded in this state.
  pending('Pending'),
  syncing('Syncing'),
  synced('Synced'),
  failed('Failed');

  const SyncStatus(this.label);

  final String label;

  bool get isTerminal => this == SyncStatus.synced;
  bool get needsAttention => this == SyncStatus.failed || this == SyncStatus.pending;
}

/// A durable record of one sync attempt.
///
/// Events are never deleted on failure — a failed push stays queued so the
/// day's takings survive a dropped connection.
class SyncEvent extends Equatable {
  const SyncEvent({
    required this.id,
    required this.type,
    required this.status,
    required this.createdAt,
    required this.summary,
    this.payload = const {},
    this.syncedAt,
    this.error,
    this.attempts = 0,
  });

  final String id;
  final SyncEventType type;
  final SyncStatus status;
  final DateTime createdAt;

  /// One-line description shown in the events log.
  final String summary;

  /// What would be transmitted. Kept so a retry needs no recomputation.
  final Map<String, Object?> payload;

  final DateTime? syncedAt;
  final String? error;
  final int attempts;

  SyncEvent copyWith({
    SyncStatus? status,
    DateTime? syncedAt,
    String? error,
    bool clearError = false,
    int? attempts,
  }) {
    return SyncEvent(
      id: id,
      type: type,
      status: status ?? this.status,
      createdAt: createdAt,
      summary: summary,
      payload: payload,
      syncedAt: syncedAt ?? this.syncedAt,
      error: clearError ? null : (error ?? this.error),
      attempts: attempts ?? this.attempts,
    );
  }

  @override
  List<Object?> get props => [id, status, attempts, syncedAt];
}