stream-chat-flutter/packages/stream_chat/lib/src/api/requests.dart

import 'package:json_annotation/json_annotation.dart';

part 'requests.g.dart';

/// Sorting options
@JsonSerializable(createFactory: false)
class SortOption<T> {
  /// Creates a new SortOption instance
  ///
  /// For example:
  /// ```dart
  /// // Sort channels by the last message date:
  /// final sorting = SortOption("last_message_at")
  /// ```
  const SortOption(
    this.field, {
    this.direction = DESC,
    this.comparator,
  });

  /// Ascending order
  // ignore: constant_identifier_names
  static const ASC = 1;

  /// Descending order
  // ignore: constant_identifier_names
  static const DESC = -1;

  /// A sorting field name
  final String field;

  /// A sorting direction
  final int direction;

  /// Sorting field Comparator required for offline sorting
  @JsonKey(ignore: true)
  final Comparator<T> comparator;

  /// Serialize model to json
  Map<String, dynamic> toJson() => _$SortOptionToJson(this);
}

/// Pagination options.
@JsonSerializable(createFactory: false, includeIfNull: false)
class PaginationParams {
  /// Creates a new PaginationParams instance
  ///
  /// For example:
  /// ```dart
  /// // limit to 50
  /// final paginationParams = PaginationParams(limit: 50);
  ///
  /// // limit to 50 with offset
  /// final paginationParams = PaginationParams(limit: 50, offset: 50);
  /// ```
  const PaginationParams({
    this.limit = 10,
    this.offset = 0,
    this.greaterThan,
    this.greaterThanOrEqual,
    this.lessThan,
    this.lessThanOrEqual,
  });

  /// The amount of items requested from the APIs.
  final int limit;

  /// The offset of requesting items.
  final int offset;

  /// Filter on ids greater than the given value.
  @JsonKey(name: 'id_gt')
  final String greaterThan;

  /// Filter on ids greater than or equal to the given value.
  @JsonKey(name: 'id_gte')
  final String greaterThanOrEqual;

  /// Filter on ids smaller than the given value.
  @JsonKey(name: 'id_lt')
  final String lessThan;

  /// Filter on ids smaller than or equal to the given value.
  @JsonKey(name: 'id_lte')
  final String lessThanOrEqual;

  /// Serialize model to json
  Map<String, dynamic> toJson() => _$PaginationParamsToJson(this);

  /// Creates a copy of [PaginationParams] with specified attributes overridden.
  PaginationParams copyWith({
    int limit,
    int offset,
    String greaterThan,
    String greaterThanOrEqual,
    String lessThan,
    String lessThanOrEqual,
  }) =>
      PaginationParams(
        limit: limit ?? this.limit,
        offset: offset ?? this.offset,
        greaterThan: greaterThan ?? this.greaterThan,
        greaterThanOrEqual: greaterThanOrEqual ?? this.greaterThanOrEqual,
        lessThan: lessThan ?? this.lessThan,
        lessThanOrEqual: lessThanOrEqual ?? this.lessThanOrEqual,
      );

  @override
  int get hashCode =>
      runtimeType.hashCode ^
      limit.hashCode ^
      offset.hashCode ^
      greaterThan.hashCode ^
      greaterThanOrEqual.hashCode ^
      lessThan.hashCode ^
      lessThanOrEqual.hashCode;

  @override
  bool operator ==(covariant PaginationParams other) =>
      identical(this, other) ||
      runtimeType == other.runtimeType &&
          limit == other.limit &&
          offset == other.offset &&
          greaterThan == other.greaterThan &&
          greaterThanOrEqual == other.greaterThanOrEqual &&
          lessThan == other.lessThan &&
          lessThanOrEqual == other.lessThanOrEqual;
}