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Library code for Realm Kotlin. This artifact is not supposed to be consumed directly, but through 'io.realm.kotlin:gradle-plugin:1.11.1' instead.

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/*
 * Copyright 2023 Realm Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package io.realm.kotlin.internal.util

import kotlinx.coroutines.ExperimentalCoroutinesApi
import kotlinx.coroutines.cancel
import kotlinx.coroutines.flow.Flow
import kotlinx.coroutines.flow.channelFlow
import kotlinx.coroutines.flow.produceIn
import kotlinx.coroutines.selects.whileSelect

/**
 * Flow wrapper that will terminate the flow once the [completionFlow] emits an element that
 * satisfies the [completionPredicate].
 */
@OptIn(ExperimentalCoroutinesApi::class)
internal fun  Flow.terminateWhen(
    completionFlow: Flow,
    completionPredicate: (S) -> Boolean
): Flow =
    channelFlow {
        val completionChannel = completionFlow.produceIn(this@channelFlow)
        val elementChannel = produceIn(this@channelFlow)
        whileSelect {
            completionChannel.onReceiveCatching {
                if (it.isClosed || completionPredicate(it.getOrThrow())) {
                    [email protected]()
                    it.exceptionOrNull()
                        ?.let { [email protected]("Couldn't retrieve element", it) }
                    false
                } else {
                    true
                }
            }
            elementChannel.onReceiveCatching {
                if (it.isClosed) {
                    [email protected]()
                    it.exceptionOrNull()
                        ?.let { [email protected]("Couldn't retrieve element", it) }
                    false
                } else {
                    [email protected](it.getOrThrow())
                    true
                }
            }
        }
    }