| // Copyright 2018 The Chromium 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 'dart:ui' show hashValues; |
| |
| import 'package:flutter/foundation.dart' show setEquals; |
| |
| import 'types.dart'; |
| import 'utils/circle.dart'; |
| |
| /// [Circle] update events to be applied to the [GoogleMap]. |
| /// |
| /// Used in [GoogleMapController] when the map is updated. |
| // (Do not re-export) |
| class CircleUpdates { |
| /// Computes [CircleUpdates] given previous and current [Circle]s. |
| CircleUpdates.from(Set<Circle> previous, Set<Circle> current) { |
| if (previous == null) { |
| previous = Set<Circle>.identity(); |
| } |
| |
| if (current == null) { |
| current = Set<Circle>.identity(); |
| } |
| |
| final Map<CircleId, Circle> previousCircles = keyByCircleId(previous); |
| final Map<CircleId, Circle> currentCircles = keyByCircleId(current); |
| |
| final Set<CircleId> prevCircleIds = previousCircles.keys.toSet(); |
| final Set<CircleId> currentCircleIds = currentCircles.keys.toSet(); |
| |
| Circle idToCurrentCircle(CircleId id) { |
| return currentCircles[id]; |
| } |
| |
| final Set<CircleId> _circleIdsToRemove = |
| prevCircleIds.difference(currentCircleIds); |
| |
| final Set<Circle> _circlesToAdd = currentCircleIds |
| .difference(prevCircleIds) |
| .map(idToCurrentCircle) |
| .toSet(); |
| |
| /// Returns `true` if [current] is not equals to previous one with the |
| /// same id. |
| bool hasChanged(Circle current) { |
| final Circle previous = previousCircles[current.circleId]; |
| return current != previous; |
| } |
| |
| final Set<Circle> _circlesToChange = currentCircleIds |
| .intersection(prevCircleIds) |
| .map(idToCurrentCircle) |
| .where(hasChanged) |
| .toSet(); |
| |
| circlesToAdd = _circlesToAdd; |
| circleIdsToRemove = _circleIdsToRemove; |
| circlesToChange = _circlesToChange; |
| } |
| |
| /// Set of Circles to be added in this update. |
| Set<Circle> circlesToAdd; |
| |
| /// Set of CircleIds to be removed in this update. |
| Set<CircleId> circleIdsToRemove; |
| |
| /// Set of Circles to be changed in this update. |
| Set<Circle> circlesToChange; |
| |
| /// Converts this object to something serializable in JSON. |
| Map<String, dynamic> toJson() { |
| final Map<String, dynamic> updateMap = <String, dynamic>{}; |
| |
| void addIfNonNull(String fieldName, dynamic value) { |
| if (value != null) { |
| updateMap[fieldName] = value; |
| } |
| } |
| |
| addIfNonNull('circlesToAdd', serializeCircleSet(circlesToAdd)); |
| addIfNonNull('circlesToChange', serializeCircleSet(circlesToChange)); |
| addIfNonNull('circleIdsToRemove', |
| circleIdsToRemove.map<dynamic>((CircleId m) => m.value).toList()); |
| |
| return updateMap; |
| } |
| |
| @override |
| bool operator ==(Object other) { |
| if (identical(this, other)) return true; |
| if (other.runtimeType != runtimeType) return false; |
| final CircleUpdates typedOther = other; |
| return setEquals(circlesToAdd, typedOther.circlesToAdd) && |
| setEquals(circleIdsToRemove, typedOther.circleIdsToRemove) && |
| setEquals(circlesToChange, typedOther.circlesToChange); |
| } |
| |
| @override |
| int get hashCode => |
| hashValues(circlesToAdd, circleIdsToRemove, circlesToChange); |
| |
| @override |
| String toString() { |
| return '_CircleUpdates{circlesToAdd: $circlesToAdd, ' |
| 'circleIdsToRemove: $circleIdsToRemove, ' |
| 'circlesToChange: $circlesToChange}'; |
| } |
| } |