added span display details to activity

lib/pangea/controllers/language_list_controller.dart

@@ -93,7 +93,6 @@ class PangeaLanguage {
   }
 
   static LanguageModel byLangCode(String langCode) {
-    final list = _langList;
     for (final element in _langList) {
       if (element.langCode == langCode) return element;
     }

lib/pangea/enum/activity_display_instructions_enum.dart

@@ -0,0 +1,13 @@
+enum ActivityDisplayInstructionsEnum { highlight, hide }
+
+extension ActivityDisplayInstructionsEnumExt
+    on ActivityDisplayInstructionsEnum {
+  String get string {
+    switch (this) {
+      case ActivityDisplayInstructionsEnum.highlight:
+        return 'highlight';
+      case ActivityDisplayInstructionsEnum.hide:
+        return 'hide';
+    }
+  }
+}

lib/pangea/models/pangea_token_model.dart

@@ -24,17 +24,19 @@ class PangeaToken {
     required this.morph,
   });
 
-  static _getLemmas(String text, dynamic json) {
+  static Lemma _getLemmas(String text, dynamic json) {
     if (json != null) {
       // July 24, 2024 - we're changing from a list to a single lemma and this is for backwards compatibility
       // previously sent tokens have lists of lemmas
       if (json is Iterable) {
         return json
-            .map<Lemma>(
-              (e) => Lemma.fromJson(e as Map<String, dynamic>),
-            )
-            .toList()
-            .cast<Lemma>();
+                .map<Lemma>(
+                  (e) => Lemma.fromJson(e as Map<String, dynamic>),
+                )
+                .toList()
+                .cast<Lemma>()
+                .firstOrNull ??
+            Lemma(text: text, saveVocab: false, form: text);
       } else {
         return Lemma.fromJson(json);
       }
@@ -61,6 +63,8 @@ class PangeaToken {
   Map<String, dynamic> toJson() => {
         _textKey: text.toJson(),
         _lemmaKey: lemma.toJson(),
+        'pos': pos,
+        'morph': morph,
       };
 
   int get end => text.offset + text.length;

lib/pangea/models/practice_activities.dart/multiple_choice_activity_model.dart

@@ -1,15 +1,18 @@
 import 'package:fluffychat/config/app_config.dart';
+import 'package:fluffychat/pangea/models/practice_activities.dart/practice_activity_model.dart';
 import 'package:flutter/material.dart';
 
 class MultipleChoice {
   final String question;
   final List<String> choices;
   final String answer;
+  final RelevantSpanDisplayDetails? spanDisplayDetails;
 
   MultipleChoice({
     required this.question,
     required this.choices,
     required this.answer,
+    this.spanDisplayDetails,
   });
 
   bool isCorrect(int index) => index == correctAnswerIndex;
@@ -28,6 +31,9 @@ class MultipleChoice {
       question: json['question'] as String,
       choices: (json['choices'] as List).map((e) => e as String).toList(),
       answer: json['answer'] ?? json['correct_answer'] as String,
+      spanDisplayDetails: json['span_display_details'] != null
+          ? RelevantSpanDisplayDetails.fromJson(json['span_display_details'])
+          : null,
     );
   }
 
@@ -36,6 +42,7 @@ class MultipleChoice {
       'question': question,
       'choices': choices,
       'answer': answer,
+      'span_display_details': spanDisplayDetails,
     };
   }
 }

lib/pangea/models/practice_activities.dart/practice_activity_model.dart

@@ -1,5 +1,7 @@
 import 'dart:developer';
 
+import 'package:collection/collection.dart';
+import 'package:fluffychat/pangea/enum/activity_display_instructions_enum.dart';
 import 'package:fluffychat/pangea/enum/activity_type_enum.dart';
 import 'package:fluffychat/pangea/enum/construct_type_enum.dart';
 import 'package:fluffychat/pangea/models/practice_activities.dart/multiple_choice_activity_model.dart';
@@ -279,4 +281,58 @@ class PracticeActivityModel {
       'free_response': freeResponse?.toJson(),
     };
   }
+
+  RelevantSpanDisplayDetails? getRelevantSpanDisplayDetails() {
+    switch (activityType) {
+      case ActivityTypeEnum.multipleChoice:
+        return multipleChoice?.spanDisplayDetails;
+      case ActivityTypeEnum.listening:
+        return null;
+      case ActivityTypeEnum.speaking:
+        return null;
+      case ActivityTypeEnum.freeResponse:
+        return null;
+      default:
+        debugger(when: kDebugMode);
+        return null;
+    }
+  }
+}
+
+/// For those activities with a relevant span, this class will hold the details
+/// of the span and how it should be displayed
+/// e.g. hide the span for conjugation activities
+class RelevantSpanDisplayDetails {
+  final int offset;
+  final int length;
+  final ActivityDisplayInstructionsEnum displayInstructions;
+
+  RelevantSpanDisplayDetails({
+    required this.offset,
+    required this.length,
+    required this.displayInstructions,
+  });
+
+  factory RelevantSpanDisplayDetails.fromJson(Map<String, dynamic> json) {
+    final ActivityDisplayInstructionsEnum? display =
+        ActivityDisplayInstructionsEnum.values.firstWhereOrNull(
+      (e) => e.string == json['display_instructions'],
+    );
+    if (display == null) {
+      debugger(when: kDebugMode);
+    }
+    return RelevantSpanDisplayDetails(
+      offset: json['offset'] as int,
+      length: json['length'] as int,
+      displayInstructions: display ?? ActivityDisplayInstructionsEnum.hide,
+    );
+  }
+
+  Map<String, dynamic> toJson() {
+    return {
+      'offset': offset,
+      'length': length,
+      'display_instructions': displayInstructions,
+    };
+  }
 }