Merge pull request #205 from m-edlund/feature/FrequencyField

feat: frequency field

yuuna/lib/creator.dart

@@ -54,3 +54,4 @@ export 'src/creator/fields/collapsed_meaning_field.dart';
 export 'src/creator/fields/expanded_meaning_field.dart';
 export 'src/creator/fields/hidden_meaning_field.dart';
 export 'src/creator/fields/tags_field.dart';
+export 'src/creator/fields/frequency_field.dart';

yuuna/lib/src/creator/anki_mapping.dart

@@ -50,6 +50,7 @@ class AnkiMapping {
         AudioField.key,
         PitchAccentField.key,
         FuriganaField.key,
+        FrequencyField.key,
         ExpandedMeaningField.key,
         CollapsedMeaningField.key,
         AudioSentenceField.key,
@@ -114,6 +115,7 @@ class AnkiMapping {
       ContextField.key: {0: ClearFieldEnhancement.key},
       PitchAccentField.key: {0: ClearFieldEnhancement.key},
       FuriganaField.key: {0: ClearFieldEnhancement.key},
+      FrequencyField.key: {0: ClearFieldEnhancement.key},
       CollapsedMeaningField.key: {0: ClearFieldEnhancement.key},
       ExpandedMeaningField.key: {0: ClearFieldEnhancement.key},
       HiddenMeaningField.key: {0: ClearFieldEnhancement.key},
@@ -160,6 +162,7 @@ class AnkiMapping {
       ContextField.key: {0: ClearFieldEnhancement.key},
       PitchAccentField.key: {0: ClearFieldEnhancement.key},
       FuriganaField.key: {0: ClearFieldEnhancement.key},
+      FrequencyField.key: {0: ClearFieldEnhancement.key},
       CollapsedMeaningField.key: {0: ClearFieldEnhancement.key},
       ExpandedMeaningField.key: {0: ClearFieldEnhancement.key},
       HiddenMeaningField.key: {0: ClearFieldEnhancement.key},
@@ -182,6 +185,7 @@ class AnkiMapping {
   static const List<String> defaultCreatorCollapsedFieldKeys = [
     TagsField.key,
     FuriganaField.key,
+    FrequencyField.key,
     PitchAccentField.key,
   ];
 

yuuna/lib/src/creator/fields/frequency_field.dart

@@ -0,0 +1,119 @@
+import 'dart:math';
+
+import 'package:flutter/material.dart';
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:yuuna/creator.dart';
+import 'package:yuuna/dictionary.dart';
+import 'package:yuuna/models.dart';
+
+/// Returns the frequency of a [DictionaryHeading] (uses harmonic mean for
+/// multiple entries, idea taken from @MarvNC).
+class FrequencyField extends Field {
+  /// Initialise this field with the predetermined and hardset values.
+  FrequencyField._privateConstructor()
+      : super(
+          uniqueKey: key,
+          label: 'Frequency',
+          description: 'Adds frequency of headword for sorting purposes,'
+              ' calculated using the harmonic mean.',
+          icon: Icons.insert_chart,
+        );
+
+  /// Get the singleton instance of this field.
+  static FrequencyField get instance => _instance;
+
+  static final FrequencyField _instance = FrequencyField._privateConstructor();
+
+  /// The unique key for this field.
+  static const String key = 'frequency';
+
+  /// Returns the frequency, set [useMinInDictionary] to true to only use the
+  /// lower value if one dictionary provides multiple values.
+  static String getFrequency({
+    required AppModel appModel,
+    required DictionaryHeading heading,
+    required SortingMethod sortBy,
+    required bool useMinInDictionary,
+  }) {
+    List<Dictionary> dictionaries = appModel.dictionaries;
+
+    List<String> unhiddenDictionaries = dictionaries
+        .where((d) => !d.isHidden(appModel.targetLanguage))
+        .map((d) => d.name)
+        .toList();
+
+    List<(double, String)> unhiddenFrequencies = heading.frequencies
+        .where((entry) =>
+            unhiddenDictionaries.contains(entry.dictionary.value!.name))
+        .map((freq) => (freq.value, freq.dictionary.value!.name))
+        .toList();
+
+    List<double> frequencies = useMinInDictionary
+        ? []
+        : unhiddenFrequencies.map((tup) => tup.$1).toList();
+
+    if (useMinInDictionary) {
+      Map<String, double> dictionariesPlusFreq = {};
+      for (var tup in unhiddenFrequencies) {
+        var entry = dictionariesPlusFreq[tup.$2];
+        dictionariesPlusFreq[tup.$2] =
+            entry == null ? tup.$1 : min(entry, tup.$1);
+      }
+      frequencies = dictionariesPlusFreq.values.toList();
+    }
+
+    unhiddenFrequencies.map((tup) => tup.$1).toList();
+
+    if (frequencies.isEmpty) {
+      return '';
+    }
+
+    double ret;
+
+    switch (sortBy) {
+      case SortingMethod.harmonic:
+        ret = frequencies.length /
+            frequencies.fold(0, (prev, freq) => (1 / freq) + prev);
+        break;
+      case SortingMethod.min:
+        ret = frequencies.reduce((f1, f2) => f1 < f2 ? f1 : f2);
+        break;
+      case SortingMethod.avg:
+        ret = frequencies.fold(0, (prev, freq) => prev + freq.toInt()) /
+            frequencies.length;
+        break;
+    }
+
+    return ret.round().toString();
+  }
+
+  @override
+  String? onCreatorOpenAction({
+    required BuildContext context,
+    required WidgetRef ref,
+    required AppModel appModel,
+    required CreatorModel creatorModel,
+    required DictionaryHeading heading,
+    required bool creatorJustLaunched,
+    required String? dictionaryName,
+  }) {
+    return getFrequency(
+      appModel: appModel,
+      heading: heading,
+      sortBy: SortingMethod.harmonic,
+      useMinInDictionary: true,
+    );
+  }
+}
+
+/// The method by which the frequency value is calculated.
+enum SortingMethod {
+  /// DEFAULT: The harmonic mean of frequencies.
+  harmonic,
+
+  /// The smallest frequency value
+  min,
+
+  /// The average frequency value
+  avg
+}

yuuna/lib/src/dictionary/dictionary_frequency.dart

@@ -30,7 +30,8 @@ class DictionaryFrequency {
   final IsarLink<Dictionary> dictionary = IsarLink<Dictionary>();
 
   @override
-  bool operator ==(Object other) => other is DictionaryPitch && id == other.id;
+  bool operator ==(Object other) =>
+      other is DictionaryFrequency && id == other.id;
 
   @override
   int get hashCode => id.hashCode;

yuuna/lib/src/models/app_model.dart

@@ -69,6 +69,7 @@ final List<Field> globalFields = List<Field>.unmodifiable(
     AudioSentenceField.instance,
     PitchAccentField.instance,
     FuriganaField.instance,
+    FrequencyField.instance,
     ContextField.instance,
     ExpandedMeaningField.instance,
     CollapsedMeaningField.instance,
@@ -879,6 +880,9 @@ class AppModel with ChangeNotifier {
       FuriganaField.instance: [
         ClearFieldEnhancement(field: FuriganaField.instance),
       ],
+      FrequencyField.instance: [
+        ClearFieldEnhancement(field: FrequencyField.instance),
+      ],
       CollapsedMeaningField.instance: [
         ClearFieldEnhancement(field: CollapsedMeaningField.instance),
         TextSegmentationEnhancement(field: CollapsedMeaningField.instance),