/*
 * Copyright (C) 2020 The Android Open Source Project
 *
 * 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 com.android.permissioncontroller.permission.data

import android.os.Handler
import android.os.Looper
import androidx.lifecycle.Observer
import java.util.concurrent.CompletableFuture

fun <T> SmartUpdateMediatorLiveData<T>.withLoadedValue(block: (T?) -> Unit) {
    val v = CompletableFuture<T?>()
    val observer =
        Observer<T?> {
            if (isInitialized) {
                v.complete(it)
            }
        }

    Handler(Looper.getMainLooper()).post { observeForever(observer) }
    try {
        block(v.get())
    } finally {
        Handler(Looper.getMainLooper()).post { removeObserver(observer) }
    }
}