PowerShell binary rotate right/left on individual bytes

rotate.ps1

function Rotate-Byte {
<#
    .SYNOPSIS
    
        Performs left/right binary rotation on individual bytes.
        Author: @harmj0y

    .DESCRIPTION

        Implements the logic to perform per-byte binary rotates right and left.
        Use a positive offset value to rotate right, negative to rotate left.

    .PARAMETER Value

        The individual byte value, or array of byte values, to bit rotate.
        Passable on the pipeline.

    .PARAMETER Offset

        The number of bits to rotate, [-8..8]. Positive values rotate right, negative
        rotate left.

    .OUTPUTS
        
        [Byte[]]. Returns a stream of bit-rotated bytes.

    .EXAMPLE
        
        PS > 131 | Rotate-Byte
        56

        Rotate 131 right by 4 bits.

    .EXAMPLE
        
        PS > Rotate-Byte 131 -3
        28

        Rotate 131 left by 3 bits.

    .EXAMPLE
        
        PS > [Byte[]]$Bytes = @(131, 130, 129)
        PS > $Bytes | Rotate-Byte
        56
        40
        24

        Rotates all bytes right by 4 bits.

    .EXAMPLE

        PS > @(131, 130, 129) | Rotate-Byte -Offset -2
        14
        10
        6

        Rotates all bytes left by 2 bits.
#>

    [CmdletBinding()]
    Param (
        [Parameter(Position = 0, ValueFromPipeline = $True, Mandatory = $True)]
        [Byte[]]
        $Value,

        [Parameter(Position = 1)]
        [Int]
        [ValidateRange(-8,8)]
        $Offset = 4
    )

    PROCESS {
        ForEach($Byte in $Value) {
            if ($Offset -lt 0) {
                1..(-$Offset) | ForEach-Object {
                    if($Byte -band 128) {
                        $Byte = 1 + ([Math]::Floor($Byte * [math]::Pow(2, 1)) -band 254)
                    }
                    else {
                        $Byte = [Math]::Floor($Byte * [math]::Pow(2, 1)) -band 254
                    }
                }
            }
            else {
                1..$Offset | ForEach-Object {
                    if($Byte -band 1) {
                        $Byte = 128 + [Math]::Floor($Byte * [math]::Pow(2, -1))
                    }
                    else {
                        $Byte = [Math]::Floor($Byte * [math]::Pow(2, -1))
                    }
                }
            }
            $Byte
        }
    }
}