Add hotel search tool. (#300)

Author: polina-c

examples/travel_app/lib/src/tools/list_hotels_tool.dart

@@ -0,0 +1,132 @@
+// Copyright 2025 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:dart_schema_builder/dart_schema_builder.dart';
+import 'package:flutter_genui/flutter_genui.dart';
+
+class HotelSearchResult {
+  final List<HotelListing> listings;
+
+  HotelSearchResult({required this.listings});
+
+  static HotelSearchResult fromJson(JsonMap json) {
+    return HotelSearchResult(
+      listings: (json['listings'] as List)
+          .map((e) => HotelListing.fromJson(e as JsonMap))
+          .toList(),
+    );
+  }
+
+  JsonMap toJson() {
+    return {'listings': listings.map((e) => e.toJson()).toList()};
+  }
+}
+
+class HotelListing {
+  final String name;
+  final String location;
+  final double pricePerNight;
+  final List<String> images;
+  final String listingId;
+
+  HotelListing({
+    required this.name,
+    required this.location,
+    required this.pricePerNight,
+    required this.listingId,
+    required this.images,
+  });
+
+  static HotelListing fromJson(JsonMap json) {
+    return HotelListing(
+      name: json['name'] as String,
+      location: json['location'] as String,
+      pricePerNight: (json['pricePerNight'] as num).toDouble(),
+      images: List<String>.from(json['images'] as List),
+      listingId: json['listingId'] as String,
+    );
+  }
+
+  JsonMap toJson() {
+    return {
+      'name': name,
+      'location': location,
+      'pricePerNight': pricePerNight,
+      'images': images,
+      'listingId': listingId,
+    };
+  }
+}
+
+class HotelSearch {
+  final String query;
+  final DateTime checkIn;
+  final DateTime checkOut;
+  final int guests;
+
+  HotelSearch({
+    required this.query,
+    required this.checkIn,
+    required this.checkOut,
+    required this.guests,
+  });
+
+  static HotelSearch fromJson(JsonMap json) {
+    return HotelSearch(
+      query: json['query'] as String,
+      checkIn: DateTime.parse(json['checkIn'] as String),
+      checkOut: DateTime.parse(json['checkOut'] as String),
+      guests: json['guests'] as int,
+    );
+  }
+
+  JsonMap toJson() {
+    return {
+      'query': query,
+      'checkIn': checkIn.toIso8601String(),
+      'checkOut': checkOut.toIso8601String(),
+      'guests': guests,
+    };
+  }
+}
+
+/// An [AiTool] for listing hotels.
+class ListHotelsTool extends AiTool<Map<String, Object?>> {
+  /// Creates a [ListHotelsTool].
+  ListHotelsTool({required this.onListHotels})
+    : super(
+        name: 'listHotels',
+        description: 'Lists hotels based on the provided criteria.',
+        parameters: S.object(
+          properties: {
+            'query': S.string(
+              description: 'The search query, e.g., "hotels in Paris".',
+            ),
+            'checkIn': S.string(
+              description: 'The check-in date in ISO 8601 format (YYYY-MM-DD).',
+              format: 'date',
+            ),
+            'checkOut': S.string(
+              description:
+                  'The check-out date in ISO 8601 format (YYYY-MM-DD).',
+              format: 'date',
+            ),
+            'guests': S.integer(
+              description: 'The number of guests.',
+              minimum: 1,
+            ),
+          },
+          required: ['query', 'checkIn', 'checkOut', 'guests'],
+        ),
+      );
+
+  /// The callback to invoke when searching hotels.
+  final HotelSearchResult Function(HotelSearch search) onListHotels;
+
+  @override
+  Future<JsonMap> invoke(JsonMap args) async {
+    final search = HotelSearch.fromJson(args);
+    return onListHotels(search).toJson();
+  }
+}

examples/travel_app/test/tools/list_hotels_tool_test.dart

@@ -0,0 +1,115 @@
+// Copyright 2025 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:flutter_test/flutter_test.dart';
+import 'package:travel_app/src/tools/list_hotels_tool.dart';
+
+void main() {
+  group('ListHotelsTool', () {
+    group('HotelListing', () {
+      test('fromJson and toJson', () {
+        final json = {
+          'name': 'The Grand Hotel',
+          'location': 'New York, NY',
+          'pricePerNight': 299.99,
+          'images': ['image1.jpg', 'image2.jpg'],
+          'listingId': '12345',
+        };
+
+        final listing = HotelListing.fromJson(json);
+
+        expect(listing.name, 'The Grand Hotel');
+        expect(listing.location, 'New York, NY');
+        expect(listing.pricePerNight, 299.99);
+        expect(listing.images, ['image1.jpg', 'image2.jpg']);
+        expect(listing.listingId, '12345');
+
+        expect(listing.toJson(), json);
+      });
+    });
+
+    group('HotelSearchResult', () {
+      test('fromJson and toJson', () {
+        final json = {
+          'listings': [
+            {
+              'name': 'The Grand Hotel',
+              'location': 'New York, NY',
+              'pricePerNight': 299.99,
+              'images': ['image1.jpg', 'image2.jpg'],
+              'listingId': '12345',
+            },
+          ],
+        };
+
+        final searchResult = HotelSearchResult.fromJson(json);
+
+        expect(searchResult.listings.length, 1);
+        expect(searchResult.listings.first.name, 'The Grand Hotel');
+
+        expect(searchResult.toJson(), json);
+      });
+    });
+
+    group('HotelSearch', () {
+      test('fromJson and toJson', () {
+        final checkIn = DateTime(2025, 10, 01);
+        final checkOut = DateTime(2025, 10, 05);
+
+        final json = {
+          'query': 'hotels in New York',
+          'checkIn': checkIn.toIso8601String(),
+          'checkOut': checkOut.toIso8601String(),
+          'guests': 2,
+        };
+
+        final search = HotelSearch.fromJson(json);
+
+        expect(search.query, 'hotels in New York');
+        expect(search.checkIn, checkIn);
+        expect(search.checkOut, checkOut);
+        expect(search.guests, 2);
+
+        expect(search.toJson(), json);
+      });
+    });
+
+    group('ListHotelsTool', () {
+      test('invoke calls onListHotels and returns correct JSON', () async {
+        final searchResult = HotelSearchResult(
+          listings: [
+            HotelListing(
+              name: 'The Grand Hotel',
+              location: 'New York, NY',
+              pricePerNight: 299.99,
+              images: ['image1.jpg', 'image2.jpg'],
+              listingId: '12345',
+            ),
+          ],
+        );
+
+        final tool = ListHotelsTool(
+          onListHotels: (search) {
+            expect(search.query, 'hotels in New York');
+            expect(search.checkIn, DateTime.parse('2025-10-01T00:00:00.000'));
+            expect(search.checkOut, DateTime.parse('2025-10-05T00:00:00.000'));
+            expect(search.guests, 2);
+            return searchResult;
+          },
+        );
+
+        final args = {
+          'query': 'hotels in New York',
+          'checkIn': '2025-10-01',
+          'checkOut': '2025-10-05',
+          'guests': 2,
+        };
+
+        final result = await tool.invoke(args);
+
+        expect(result, searchResult.toJson());
+      });
+    });
+  });
+}