Refactor json converters.

Author: BirjuVachhani

lib/codelessly_api.dart

@@ -16,3 +16,4 @@ export 'src/api/nodes/nodes.dart';
 export 'src/api/regexes.dart';
 export 'src/api/typed_value.dart';
 export 'src/api/utils.dart';
+export 'src/api/converters.dart';

lib/src/api/converters.dart

@@ -0,0 +1,104 @@
+import 'package:json_annotation/json_annotation.dart';
+
+import 'node_json_converter.dart';
+import 'nodes/base_node.dart';
+
+/// Top level converter for serializing [DateTime] to [millisecondsSinceEpoch].
+class DateTimeConverter extends JsonConverter<DateTime, int?> {
+  /// Creates a new instance of [DateTimeConverter].
+  const DateTimeConverter();
+
+  @override
+  DateTime fromJson(int? json) => deserialize(json);
+
+  @override
+  int? toJson(DateTime object) => serialize(object);
+
+  /// Serializes [DateTime] to [int].
+  static int? serialize(DateTime object) =>
+      object.toUtc().millisecondsSinceEpoch;
+
+  /// Deserializes [int] to [DateTime].
+  static DateTime deserialize(int? json) {
+    return json != null
+        ? DateTime.fromMillisecondsSinceEpoch(json).toLocal()
+        : DateTime.now();
+  }
+}
+
+/// Top level converter for serializing [DateTime] to [millisecondsSinceEpoch].
+class NullableDateTimeConverter extends JsonConverter<DateTime?, int?> {
+  /// Creates a new instance of [NullableDateTimeConverter].
+  const NullableDateTimeConverter();
+
+  @override
+  DateTime? fromJson(int? json) => deserialize(json);
+
+  @override
+  int? toJson(DateTime? object) => serialize(object);
+
+  /// Serializes [DateTime] to [int].
+  static int? serialize(DateTime? object) =>
+      object?.toUtc().millisecondsSinceEpoch;
+
+  /// Deserializes [int] to [DateTime].
+  static DateTime? deserialize(int? json) {
+    return json != null
+        ? DateTime.fromMillisecondsSinceEpoch(json).toLocal()
+        : null;
+  }
+}
+
+/// Top level converter for serializing Nodes map to and from JSON.
+class NodesMapConverter
+    extends JsonConverter<Map<String, BaseNode>, Map<String, dynamic>> {
+  /// Creates a new instance of [NodesMapConverter].
+  const NodesMapConverter();
+
+  @override
+  Map<String, BaseNode> fromJson(Map<String, dynamic> json) =>
+      deserialize(json);
+
+  @override
+  Map<String, dynamic> toJson(Map<String, BaseNode> object) =>
+      serialize(object);
+
+  /// Top level function to deserialize a JSON Map into a map of node ID to node.
+  static Map<String, BaseNode> deserialize(Map<String, dynamic> value) => {
+        for (final MapEntry(key: key, value: value) in value.entries)
+          key: NodeJsonConverter.instance.fromJson(value)!,
+      };
+
+  /// Top level function to serialize a map of node ID to node into a JSON map.
+  static Map<String, dynamic> serialize(Map<String, BaseNode> nodes) => {
+        for (final MapEntry(key: key, value: value) in nodes.entries)
+          key: NodeJsonConverter.instance.toJson(value),
+      };
+}
+
+/// Top level converter for serializing map of DateTime.
+class DateTimeMapConverter
+    extends JsonConverter<Map<String, DateTime>, Map<String, int>> {
+  /// Creates a new instance of [DateTimeMapConverter].
+  const DateTimeMapConverter();
+
+  @override
+  Map<String, DateTime> fromJson(Map<String, int> json) => deserialize(json);
+
+  @override
+  Map<String, int> toJson(Map<String, DateTime> object) => serialize(object);
+
+  /// Top level function for deserializing the millis from JSON as the values of
+  /// a map to [DateTime].
+  static Map<String, DateTime> deserialize(Map<String, dynamic> value) => {
+        for (final MapEntry(key: key, value: value) in value.entries)
+          key: DateTime.fromMillisecondsSinceEpoch(value).toLocal(),
+      };
+
+  /// Top level function for serializing a map of with [DateTime] as the values
+  /// to [millisecondsSinceEpoch].
+  static Map<String, int> serialize(Map<String, DateTime> dates) => {
+        for (final MapEntry(key: key, value: value) in dates.entries)
+          key: value.toUtc().millisecondsSinceEpoch,
+      };
+}

lib/src/api/custom_component.dart

@@ -5,9 +5,9 @@
 import 'package:equatable/equatable.dart';
 import 'package:json_annotation/json_annotation.dart';
 
+import 'converters.dart';
 import 'mixins.dart';
 import 'models/models.dart';
-import 'utils.dart';
 
 part 'custom_component.g.dart';
 
@@ -25,7 +25,7 @@ class CustomComponent with EquatableMixin, SerializableMixin {
   final ComponentData data;
 
   /// Date and time when the component was created.
-  @JsonKey(fromJson: jsonToDate, toJson: dateToJson)
+  @DateTimeConverter()
   final DateTime createdAt;
 
   /// The thumbnail URL for the component preview.

lib/src/api/custom_component.g.dart

@@ -1,8 +1,8 @@
 import 'package:equatable/equatable.dart';
 import 'package:json_annotation/json_annotation.dart';
 
+import '../converters.dart';
 import '../mixins.dart';
-import '../utils.dart';
 import 'models.dart';
 
 part 'condition.g.dart';
@@ -334,7 +334,7 @@ sealed class BaseCondition with EquatableMixin, SerializableMixin {
   final String id;
 
   /// last updated timestamp
-  @JsonKey(fromJson: jsonToDate, toJson: dateToJson)
+  @DateTimeConverter()
   final DateTime lastUpdated;
 
   /// Creates a base condition.
@@ -538,7 +538,7 @@ class CanvasConditions with EquatableMixin {
   final Map<String, BaseCondition> conditions;
 
   /// Last updated time of this canvas.
-  @JsonKey(toJson: dateToJson, fromJson: jsonToDate)
+  @DateTimeConverter()
   final DateTime lastUpdated;
 
   /// ID of the project this canvas belongs to.

lib/src/api/models/condition.dart

@@ -158,7 +158,7 @@ class CanvasVariables with EquatableMixin {
   final Map<String, CanvasVariableData> variables;
 
   /// Last updated time of this canvas.
-  @JsonKey(toJson: dateToJson, fromJson: jsonToDate)
+  @DateTimeConverter()
   final DateTime lastUpdated;
 
   /// ID of the project this canvas belongs to.

lib/src/api/models/condition.g.dart

@@ -5,9 +5,9 @@
 import 'package:equatable/equatable.dart';
 import 'package:json_annotation/json_annotation.dart';
 
+import '../converters.dart';
 import '../mixins.dart';
 import '../models/models.dart';
-import '../utils.dart';
 import 'nodes.dart';
 
 part 'canvas_node.g.dart';
@@ -28,7 +28,7 @@ class CanvasNode extends ParentNode
   final bool supportsPadding = true;
 
   /// Time of creation.
-  @JsonKey(fromJson: jsonToDate, toJson: dateToJson)
+  @DateTimeConverter()
   late DateTime createdTimestamp;
 
   /// Holds configurable properties for the canvas.