1 /*
<lambda>null2 * 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.internal.util.logDuration
20 import java.util.concurrent.atomic.AtomicBoolean
21
22 internal class InputNode<A>(
23 private val activate: EvalScope.() -> Unit = {},
<lambda>null24 private val deactivate: () -> Unit = {},
25 ) : PushNode<A> {
26
27 private val downstreamSet = DownstreamSet()
28 val activated = AtomicBoolean(false)
29
30 private val transactionCache = TransactionCache<A>()
31 private val epoch
32 get() = transactionCache.epoch
33
34 override val depthTracker: DepthTracker = DepthTracker()
35
hasCurrentValuenull36 override fun hasCurrentValue(logIndent: Int, evalScope: EvalScope): Boolean =
37 epoch == evalScope.epoch
38
39 fun visit(evalScope: EvalScope, value: A) {
40 transactionCache.put(evalScope, value)
41 if (!scheduleAll(0, downstreamSet, evalScope)) {
42 evalScope.scheduleDeactivation(this@InputNode)
43 }
44 }
45
removeDownstreamnull46 override fun removeDownstream(downstream: Schedulable) {
47 downstreamSet.remove(downstream)
48 }
49
deactivateIfNeedednull50 override fun deactivateIfNeeded() {
51 if (downstreamSet.isEmpty() && activated.getAndSet(false)) {
52 deactivate()
53 }
54 }
55
scheduleDeactivationIfNeedednull56 override fun scheduleDeactivationIfNeeded(evalScope: EvalScope) {
57 if (downstreamSet.isEmpty()) {
58 evalScope.scheduleDeactivation(this)
59 }
60 }
61
addDownstreamnull62 override fun addDownstream(downstream: Schedulable) {
63 downstreamSet.add(downstream)
64 }
65
addDownstreamAndActivateIfNeedednull66 fun addDownstreamAndActivateIfNeeded(downstream: Schedulable, evalScope: EvalScope) {
67 val needsActivation = run {
68 val wasEmpty = downstreamSet.isEmpty()
69 downstreamSet.add(downstream)
70 wasEmpty && !activated.getAndSet(true)
71 }
72 if (needsActivation) {
73 activate(evalScope)
74 }
75 }
76
removeDownstreamAndDeactivateIfNeedednull77 override fun removeDownstreamAndDeactivateIfNeeded(downstream: Schedulable) {
78 downstreamSet.remove(downstream)
79 val needsDeactivation = downstreamSet.isEmpty() && activated.getAndSet(false)
80 if (needsDeactivation) {
81 deactivate()
82 }
83 }
84
getPushEventnull85 override fun getPushEvent(logIndent: Int, evalScope: EvalScope): A =
86 logDuration(logIndent, "Input.getPushEvent", false) {
87 transactionCache.getCurrentValue(evalScope)
88 }
89 }
90
downstreamnull91 internal fun <A> InputNode<A>.activated() = EventsImplCheap { downstream ->
92 val input = this@activated
93 addDownstreamAndActivateIfNeeded(downstream, evalScope = this)
94 ActivationResult(
95 connection = NodeConnection(input, input),
96 needsEval = input.hasCurrentValue(0, evalScope = this),
97 )
98 }
99
100 internal data object AlwaysNode : PushNode<Unit> {
101
102 override val depthTracker = DepthTracker()
103
hasCurrentValuenull104 override fun hasCurrentValue(logIndent: Int, evalScope: EvalScope): Boolean = true
105
106 override fun removeDownstream(downstream: Schedulable) {}
107
deactivateIfNeedednull108 override fun deactivateIfNeeded() {}
109
scheduleDeactivationIfNeedednull110 override fun scheduleDeactivationIfNeeded(evalScope: EvalScope) {}
111
addDownstreamnull112 override fun addDownstream(downstream: Schedulable) {}
113
removeDownstreamAndDeactivateIfNeedednull114 override fun removeDownstreamAndDeactivateIfNeeded(downstream: Schedulable) {}
115
getPushEventnull116 override fun getPushEvent(logIndent: Int, evalScope: EvalScope) =
117 logDuration(logIndent, "Always.getPushEvent", false) { Unit }
118 }
119