intermediate

2024-12-12 09:44:33 +01:00
parent 0710116feb
commit 6b2ae28828
108 changed files with 5531 additions and 2265 deletions
@@ -0,0 +1,48 @@
+typedef ToString<T> = String? Function(T);
+
+class TokenizedFilter<T> {
+  final Iterable<T> original;
+  final List<T> filtered;
+
+  static List<String> _tokenize(String input) {
+    return input
+        .trim()
+        .toLowerCase()
+        .replaceAll(RegExp(r'[^\w\s]'), '') // Remove punctuation
+        .split(RegExp(r'\s+')) // Split on whitespace
+        .where((word) => word.isNotEmpty)
+        .toList();
+  }
+
+  static bool _matchTokens(
+    List<String> queryTokens,
+    List<String> targetTokens,
+  ) {
+    return queryTokens.every(
+      (queryToken) =>
+          targetTokens.any((targetToken) => targetToken.contains(queryToken)),
+    );
+  }
+
+  factory TokenizedFilter({
+    required Iterable<T> items,
+    required ToString<T> toString,
+    required String query,
+  }) {
+    final queryTokens = _tokenize(query);
+
+    final filtered = items.where((item) {
+      final itemString = toString(item);
+      if (itemString == null || itemString.isEmpty) {
+        return false;
+      }
+
+      final itemTokens = _tokenize(itemString);
+      return _matchTokens(queryTokens, itemTokens);
+    }).toList();
+
+    return TokenizedFilter._(items, filtered);
+  }
+
+  const TokenizedFilter._(this.original, this.filtered);
+}