feat: Implement PandoraEntity.parse

Author: hacker1024

lib/src/common/entities/pandora_entity.dart

@@ -1,10 +1,12 @@
 import 'package:iapetus/src/common/entities/pandora_type.dart';
 
-abstract class PandoraEntity {
+abstract interface class PandoraEntity {
   PandoraType get pandoraType;
 
   String get pandoraId;
 
+  factory PandoraEntity.parse(String pandoraId) = _ReconstructedPandoraEntity;
+
   /// A equality function useful for keeping Pandora entities in sets.
   static bool setEquals(
     PandoraEntity pandoraEntity1,
@@ -16,3 +18,34 @@ abstract class PandoraEntity {
   static int setHashCode(PandoraEntity pandoraEntity) =>
       pandoraEntity.pandoraId.hashCode;
 }
+
+/// A [PandoraEntity] constructed from a raw Pandora ID with type inference.
+class _ReconstructedPandoraEntity implements PandoraEntity {
+  @override
+  final PandoraType pandoraType;
+
+  @override
+  final String pandoraId;
+
+  _ReconstructedPandoraEntity(this.pandoraId)
+      : pandoraType = _idTable[pandoraId.substring(0, 2)] ??
+            (throw FormatException('Unknown Pandora type!', pandoraId, 0));
+
+  @override
+  String toString() {
+    return '_ReconstructedPandoraEntity{pandoraType: $pandoraType, pandoraId: $pandoraId}';
+  }
+
+  @override
+  bool operator ==(Object other) =>
+      identical(this, other) ||
+      other is _ReconstructedPandoraEntity &&
+          runtimeType == other.runtimeType &&
+          pandoraId == other.pandoraId;
+
+  @override
+  int get hashCode => pandoraId.hashCode;
+
+  static final _idTable =
+      pandoraTypeEnumMap.map((key, value) => MapEntry(value, key));
+}