| 1 | import 'dart:async'; |
| 2 | import 'package:hive/hive.dart'; |
| 3 | import 'package:mobx/mobx.dart'; |
| 4 | import 'package:cw_core/keyable.dart'; |
| 5 | |
| 6 | void connectMapToListWithTransform<T extends Keyable, Y extends Keyable>( |
| 7 | ObservableMap<dynamic, T> source, ObservableList<Y> dest, Y Function(T?) transform, |
| 8 | {bool Function(T?)? filter}) { |
| 9 | source.observe((MapChange<dynamic, T> change) { |
| 10 | if (change.type == null) { |
| 11 | return; |
| 12 | } |
| 13 | |
| 14 | switch (change.type) { |
| 15 | case OperationType.add: |
| 16 | if (filter?.call(change.newValue) ?? true) { |
| 17 | dest.add(transform(change.newValue)); |
| 18 | } |
| 19 | break; |
| 20 | case OperationType.remove: |
| 21 | // Hive could has equal index and key |
| 22 | dest.removeWhere((elem) => elem.keyIndex == (change.key ?? change.newValue?.keyIndex)); |
| 23 | break; |
| 24 | case OperationType.update: |
| 25 | for (var i = 0; i < dest.length; i++) { |
| 26 | final item = dest[i]; |
| 27 | |
| 28 | if (item.keyIndex == change.key) { |
| 29 | dest[i] = transform(change.newValue); |
| 30 | } |
| 31 | } |
| 32 | break; |
| 33 | default: |
| 34 | break; |
| 35 | } |
| 36 | }); |
| 37 | } |
| 38 | |
| 39 | typedef Filter<T> = bool Function(T); |
| 40 | typedef Transform<T, Y> = Y Function(T); |
| 41 | |
| 42 | enum ChangeType { update, delete, add } |
| 43 | |
| 44 | class EntityChange<T extends Keyable> { |
| 45 | EntityChange(this.value, this.type, {dynamic key}) : _key = key; |
| 46 | |
| 47 | dynamic get key => _key ?? value.keyIndex; |
| 48 | final T value; |
| 49 | final ChangeType type; |
| 50 | final dynamic _key; |
| 51 | } |
| 52 | |
| 53 | extension MobxBindable<T extends Keyable> on Box<T> { |
| 54 | StreamSubscription<BoxEvent> bindToList( |
| 55 | ObservableList<T> dest, { |
| 56 | bool initialFire = false, |
| 57 | Filter<T>? filter, |
| 58 | }) { |
| 59 | if (initialFire) { |
| 60 | final res = filter != null ? values.where(filter) : values; |
| 61 | dest.addAll(res); |
| 62 | } |
| 63 | |
| 64 | return watch().listen((event) { |
| 65 | if (filter != null && event.value != null && !filter(event.value as T)) { |
| 66 | return; |
| 67 | } |
| 68 | |
| 69 | dest.acceptBoxChange(event); |
| 70 | }); |
| 71 | } |
| 72 | |
| 73 | StreamSubscription<BoxEvent> bindToListWithTransform<Y extends Keyable>( |
| 74 | ObservableList<Y> dest, |
| 75 | Transform<T, Y> transform, { |
| 76 | bool initialFire = false, |
| 77 | Filter<T>? filter, |
| 78 | }) { |
| 79 | if (initialFire) { |
| 80 | dest.addAll(values.map((value) => transform(value))); |
| 81 | } |
| 82 | |
| 83 | return watch().listen((event) { |
| 84 | if (filter != null && event.value != null && !filter(event.value as T)) { |
| 85 | return; |
| 86 | } |
| 87 | |
| 88 | dest.acceptBoxChange(event, transformed: event.deleted ? null : transform(event.value as T)); |
| 89 | }); |
| 90 | } |
| 91 | } |
| 92 | |
| 93 | extension HiveBindable<T extends Keyable> on ObservableList<T> { |
| 94 | Stream<EntityChange<T>> listen() { |
| 95 | // ignore: close_sinks |
| 96 | final controller = StreamController<EntityChange<T>>(); |
| 97 | |
| 98 | observe((ListChange<T> change) { |
| 99 | change.elementChanges?.forEach((change) { |
| 100 | ChangeType type; |
| 101 | |
| 102 | switch (change.type) { |
| 103 | case OperationType.add: |
| 104 | type = ChangeType.add; |
| 105 | break; |
| 106 | case OperationType.remove: |
| 107 | type = ChangeType.delete; |
| 108 | break; |
| 109 | case OperationType.update: |
| 110 | type = ChangeType.update; |
| 111 | break; |
| 112 | } |
| 113 | |
| 114 | final value = change.newValue as T; |
| 115 | controller.add(EntityChange(value, type, |
| 116 | key: type == ChangeType.delete ? change.index : value.keyIndex)); |
| 117 | }); |
| 118 | }); |
| 119 | |
| 120 | return controller.stream; |
| 121 | } |
| 122 | |
| 123 | StreamSubscription<EntityChange<T>> bindToList(ObservableList<T> dest) => |
| 124 | listen().listen((event) => dest.acceptEntityChange(event)); |
| 125 | |
| 126 | void acceptBoxChange(BoxEvent event, {T? transformed}) { |
| 127 | if (event.deleted) { |
| 128 | removeWhere((el) { |
| 129 | return el.keyIndex == event.key; |
| 130 | }); |
| 131 | |
| 132 | return; |
| 133 | } |
| 134 | |
| 135 | final dynamic value = transformed ?? event.value; |
| 136 | |
| 137 | if (value is T) { |
| 138 | final index = indexWhere((el) => el.keyIndex == value.keyIndex); |
| 139 | |
| 140 | if (index > -1) { |
| 141 | this.setAll(index, [value]); // FIXME: fixme |
| 142 | } else { |
| 143 | add(value); |
| 144 | } |
| 145 | } |
| 146 | } |
| 147 | |
| 148 | void acceptEntityChange(EntityChange<T> event) { |
| 149 | if (event.type == ChangeType.delete) { |
| 150 | removeWhere((el) => el.keyIndex == event.key); |
| 151 | return; |
| 152 | } |
| 153 | |
| 154 | final dynamic value = event.value; |
| 155 | |
| 156 | if (value is T) { |
| 157 | final index = indexWhere((el) => el.keyIndex == value.keyIndex); |
| 158 | |
| 159 | if (index > -1) { |
| 160 | this.setAll(index, [value]); // FIXME: fixme |
| 161 | } else { |
| 162 | add(value); |
| 163 | } |
| 164 | } |
| 165 | } |
| 166 | } |