uranos/blokk-packet-codecs/src/main/kotlin/space/blokk/util/CompactedBitArray.kt

@file:Suppress("DuplicatedCode")

package space.blokk.util

fun IntArray.toCompactLongArray(bitsPerEntry: Int): LongArray {
    val itemsPerLong = Long.SIZE_BITS / bitsPerEntry
    val array = LongArray(size / itemsPerLong)

    var totalIndex = 0
    for(longIndex in array.indices) {
        var long: Long = 0
        for (index in 0 until itemsPerLong) {
            long = (get(totalIndex).toLong() shl (index * bitsPerEntry)) or long
            totalIndex++
        }

        array[longIndex] = long
    }

    return array
}

fun ByteArray.toCompactLongArray(bitsPerEntry: Int): LongArray {
    val itemsPerLong = Long.SIZE_BITS / bitsPerEntry
    val array = LongArray(size / itemsPerLong)

    var totalIndex = 0
    for(longIndex in array.indices) {
        var long: Long = 0
        for (index in 0 until itemsPerLong) {
            long = (get(totalIndex).toLong() shl (index * bitsPerEntry)) or long
            totalIndex++
        }

        array[longIndex] = long
    }

    return array
}