/*
 * 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.systemui.util

import android.util.IndentingPrintWriter
import android.view.ViewGroup
import java.io.PrintWriter

/** [Sequence] that yields all of the direct children of this [ViewGroup] */
val ViewGroup.children
    get() = sequence {
        for (i in 0 until childCount) yield(getChildAt(i))
    }

/** Inclusive version of [Iterable.takeWhile] */
fun <T> Sequence<T>.takeUntil(pred: (T) -> Boolean): Sequence<T> = sequence {
    for (x in this@takeUntil) {
        yield(x)
        if (pred(x)) {
            break
        }
    }
}

/**
 * If `this` is an [IndentingPrintWriter], it will process block inside an indentation level.
 *
 * If not, this will just process block.
 */
inline fun PrintWriter.indentIfPossible(block: PrintWriter.() -> Unit) {
    if (this is IndentingPrintWriter) increaseIndent()
    block()
    if (this is IndentingPrintWriter) decreaseIndent()
}