xref: /aosp_15_r20/frameworks/base/packages/SystemUI/utils/kairos/src/com/android/systemui/kairos/internal/FilterNode.kt (revision d57664e9bc4670b3ecf6748a746a57c557b6bc9e)
1 /*
2  * Copyright (C) 2024 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package com.android.systemui.kairos.internal
18 
19 import com.android.systemui.kairos.util.Just
20 import com.android.systemui.kairos.util.Maybe
21 import com.android.systemui.kairos.util.just
22 import com.android.systemui.kairos.util.none
23 
mapMaybeNodenull24 internal inline fun <A, B> mapMaybeNode(
25     crossinline getPulse: suspend EvalScope.() -> TFlowImpl<A>,
26     crossinline f: suspend EvalScope.(A) -> Maybe<B>,
27 ): TFlowImpl<B> {
28     return DemuxImpl(
29             {
30                 mapImpl(getPulse) {
31                     val maybeResult = f(it)
32                     if (maybeResult is Just) {
33                         mapOf(Unit to maybeResult.value)
34                     } else {
35                         emptyMap()
36                     }
37                 }
38             },
39             numKeys = 1,
40         )
41         .eventsForKey(Unit)
42 }
43 
filterNodenull44 internal inline fun <A> filterNode(
45     crossinline getPulse: suspend EvalScope.() -> TFlowImpl<A>,
46     crossinline f: suspend EvalScope.(A) -> Boolean,
47 ): TFlowImpl<A> = mapMaybeNode(getPulse) { if (f(it)) just(it) else none }
48