package com.infendro.bytes.longarray

import com.infendro.bytes.ByteOrder
import com.infendro.bytes.ByteOrder.BIG_ENDIAN
import com.infendro.bytes.ByteOrder.LITTLE_ENDIAN

fun LongArray.copyInto(
    destination: ByteArray,
    destinationOffset: Int = 0,
    startIndex: Int = 0,
    endIndex: Int = size,
    order: ByteOrder = BIG_ENDIAN,
) {
    val length = endIndex - startIndex
    require(length >= 0)
    require(startIndex in 0..(size - length))
    require(destinationOffset in 0..(destination.size - (length * 8)))

    when (order) {
        BIG_ENDIAN -> {
            repeat(length) { i ->
                val offset = destinationOffset + (i * 8)
                val value = this[startIndex + i]
                destination[offset] = (value shr 56).toByte()
                destination[offset + 1] = (value shr 48).toByte()
                destination[offset + 2] = (value shr 40).toByte()
                destination[offset + 3] = (value shr 32).toByte()
                destination[offset + 4] = (value shr 24).toByte()
                destination[offset + 5] = (value shr 16).toByte()
                destination[offset + 6] = (value shr 8).toByte()
                destination[offset + 7] = value.toByte()
            }
        }
        LITTLE_ENDIAN -> {
            repeat(length) { i ->
                val offset = destinationOffset + (i * 8)
                val value = this[startIndex + i]
                destination[offset] = value.toByte()
                destination[offset + 1] = (value shr 8).toByte()
                destination[offset + 2] = (value shr 16).toByte()
                destination[offset + 3] = (value shr 24).toByte()
                destination[offset + 4] = (value shr 32).toByte()
                destination[offset + 5] = (value shr 40).toByte()
                destination[offset + 6] = (value shr 48).toByte()
                destination[offset + 7] = (value shr 56).toByte()
            }
        }
    }
}

fun LongArray.copyInto(
    destination: UByteArray,
    destinationOffset: Int = 0,
    startIndex: Int = 0,
    endIndex: Int = size,
    order: ByteOrder = BIG_ENDIAN,
) = copyInto(destination.asByteArray(), destinationOffset, startIndex, endIndex, order)