chore: add high level classes

Signed-off-by: The one with the braid <the-one@with-the-braid.cf>

lib/src/models/pass_structure_dictionary.dart

@@ -0,0 +1,171 @@
+import 'package:pkpass/src/utils/mabe_decode.dart';
+
+/// Keys that define the structure of the pass.
+///
+/// These keys are used for all pass styles and partition the fields into the various parts of the pass.
+class PassStructureDictionary {
+  /// Fields to be displayed in the header on the front of the pass.
+  ///
+  /// Use header fields sparingly; unlike all other fields, they remain visible when a stack of passes are displayed.
+  final List<DictionaryField> headerFields;
+
+  /// Fields to be displayed prominently on the front of the pass.
+  final List<DictionaryField> primaryFields;
+
+  /// Fields to be displayed on the front of the pass.
+  final List<DictionaryField> secondaryFields;
+
+  /// Fields to be on the back of the pass.
+  final List<DictionaryField> backFields;
+
+  /// Additional fields to be displayed on the front of the pass.
+  final List<DictionaryField> auxiliaryFields;
+
+  /// Required for boarding passes; otherwise not allowed. Type of transit.
+  final TransitType? transitType;
+
+  const PassStructureDictionary({
+    this.headerFields = const [],
+    this.primaryFields = const [],
+    this.secondaryFields = const [],
+    this.backFields = const [],
+    this.auxiliaryFields = const [],
+    this.transitType,
+  });
+
+  factory PassStructureDictionary.fromJson(Map<String, Object?> json) =>
+      PassStructureDictionary(
+        headerFields: (json['headerFields'] as List?)
+                ?.map((i) => DictionaryField.fromJson(i))
+                .toList() ??
+            [],
+        primaryFields: (json['primaryFields'] as List?)
+                ?.map((i) => DictionaryField.fromJson(i))
+                .toList() ??
+            [],
+        secondaryFields: (json['secondaryFields'] as List?)
+                ?.map((i) => DictionaryField.fromJson(i))
+                .toList() ??
+            [],
+        backFields: (json['backFields'] as List?)
+                ?.map((i) => DictionaryField.fromJson(i))
+                .toList() ??
+            [],
+        auxiliaryFields: (json['auxiliaryFields'] as List?)
+                ?.map((i) => DictionaryField.fromJson(i))
+                .toList() ??
+            [],
+        transitType: _TarnsitType.parse(json['transitType'] as String?),
+      );
+}
+
+/// Information about a field.
+class DictionaryField {
+  /// The key must be unique within the scope of the entire pass. For example, “departure-gate.”
+  final String key;
+
+  /// Value of the field, for example, 42.
+  final DictionaryValue value;
+
+  /// Label text for the field.
+  final String? label;
+
+  /// Format string for the alert text that is displayed when the pass is updated. The format string must contain the escape %@, which is replaced with the field’s new value. For example, “Gate changed to %@.”
+  ///
+  /// If you don’t specify a change message, the user isn’t notified when the field changes.
+  final String? changeMessage;
+
+  /// Alignment for the field’s contents.
+  final PassTextAlign? textAlignment;
+
+  /// Attributed value of the field.
+  ///
+  /// The value may contain HTML markup for links. Only the <a> tag and its href attribute are supported. For example, the following is key-value pair specifies a link with the text “Edit my profile”:
+  ///
+  /// "attributedValue": "<a href='http://example.com/customers/123'>Edit my profile</a>"
+  ///
+  /// This key’s value overrides the text specified by the value key.
+  final DictionaryValue? attributedValue;
+
+  const DictionaryField({
+    required this.key,
+    required this.value,
+    this.label,
+    this.changeMessage,
+    this.textAlignment,
+    this.attributedValue,
+  });
+
+  factory DictionaryField.fromJson(Map<String, Object?> json) =>
+      DictionaryField(
+        key: json['key'] as String,
+        value: DictionaryValue.parse(json['value'] as String),
+        label: json['label'] as String?,
+        changeMessage: json['changeMessage'] as String?,
+        textAlignment:
+            MaybeDecode.maybeTextAlign(json['textAlignment'] as String?),
+        attributedValue: json['attributedValue'] == null
+            ? null
+            : DictionaryValue.parse(json['attributedValue'] as String),
+      );
+}
+
+abstract class DictionaryValue {
+  const DictionaryValue();
+
+  factory DictionaryValue.parse(String value) {
+    final number = int.tryParse(value);
+    if (number != null) return NumberDictionaryValue(number);
+
+    final dateTime = DateTime.tryParse(value);
+    if (dateTime != null) return DateTimeDictionaryValue(dateTime);
+
+    return StringDictionaryValue(value);
+  }
+}
+
+class StringDictionaryValue extends DictionaryValue {
+  final String string;
+
+  const StringDictionaryValue(this.string);
+}
+
+class DateTimeDictionaryValue extends DictionaryValue {
+  final DateTime dateTime;
+
+  const DateTimeDictionaryValue(this.dateTime);
+}
+
+class NumberDictionaryValue extends DictionaryValue {
+  final int number;
+
+  const NumberDictionaryValue(this.number);
+}
+
+enum TransitType {
+  air,
+  boat,
+  bus,
+  generic,
+  train,
+}
+
+enum PassTextAlign { left, center, right, natural }
+
+extension _TarnsitType on TransitType {
+  static TransitType? parse(String? type) {
+    if (type == null) return null;
+    switch (type) {
+      case 'PKTransitTypeAir':
+        return TransitType.air;
+      case 'PKTransitTypeBoat':
+        return TransitType.boat;
+      case 'PKTransitTypeBus':
+        return TransitType.bus;
+      case 'PKTransitTypeTrain':
+        return TransitType.train;
+      default:
+        return TransitType.generic;
+    }
+  }
+}