Function for writing to a log file, either in plain or CMTrace format, with the option to write the information to the host as well (for debugging purposes). Based on https://www.wolffhaven45.com/powershell/write-cmtracelog-dropping-logs-like-a-boss/ and https://janikvonrotz.ch/2017/10/26/powershell-logging-in-cmtrace-format/

Write-Log.ps1

[CmdletBinding()]
param()

#region FUNCTIONS
function Write-Log
{
    <#
    .SYNOPSIS
        Write information to a log file, optionally in CMTrace format
    .LINK
        https://gist.github.com/dancing-groot/acd2faf51d6dacebf5af2005294cf1f7
    .NOTES
        Version:    2022.12.09
        Author:     @dancing-groot
    #>
    [cmdletbinding()]
    param (
        [parameter(Mandatory = $true)]
        [string]$Path,

        [parameter(Mandatory = $true)]
        [string]$Message,

        [parameter(Mandatory = $true)]
        [string]$Component,

        [ValidateSet('Warning', 'Error', 'Verbose', 'Debug', 'Information', 'Info')] 
        [string]$Type = "Info",

        [switch]$CMTrace,

        [bool]$WriteBackToHost = $false
    )

    if ($Type -eq "Information") { $Type = "Info" }

    if ($CMTrace)
    {
        switch ($Type)
        {
            "Info"    { $severity = 1; break }
            "Warning" { $severity = 2; break }
            "Error"   { $severity = 3; break }
            "Verbose" { $severity = 4; break }
            "Debug"   { $severity = 5; break }
        }

        # Create a log entry
        $content = "<![LOG[$($Type.ToUpper()): $Message]LOG]!>" + `
            "<time=`"$(Get-Date -Format "HH:mm:ss.ffffff")`" " + `
            "date=`"$(Get-Date -Format "M-d-yyyy")`" " + `
            "component=`"$Component`" " + `
            "context=`"$([System.Security.Principal.WindowsIdentity]::GetCurrent().Name)`" " + `
            "type=`"$severity`" " + `
            "thread=`"$($PID)`" " + `
            "file=`"$((Get-PSCallStack)[1].Command)`">"
    }
    else
    {
        $content = "$(Get-Date -UFormat '%Y.%m.%d %T')" + "`t" + `
            $Component + "`t" + `
            $Type + "`t" + `
            $Message
    }

    # Write the line to the log file
    Add-Content -Path $Path -Value $content

    if ($WriteBackToHost)
    {
        switch ($Type)
        {
            "Info"    { Write-Information "$Message" -InformationAction Continue; break }
            "Warning" { Write-Warning $Message -WarningAction Continue; break }
            "Error"   { Write-Host "ERROR: $Message" -ForegroundColor Red; break }
            "Verbose" { Write-Verbose $Message; break }
            "Debug"   { Write-Debug $Message; break }
        }
    }
} # Write-Log
#endregion FUNCTIONS

#region DECLARATION
$LogComponent = "Setup" # Used for grouping entries for what you are doing, especially important if you are doing multiple tasks in this script or if multiple scripts write to the same log file
$LogName = ($MyInvocation.MyCommand.Name).TrimEnd(".ps1")

$LogFile = "$PSScriptRoot\$LogName.log"
$LogParams = @{Path = $LogFile; Component = $LogComponent; WriteBackToHost = $true } # Messages will be written to the log and to the prompt

$LogFileCMTrace = "$PSScriptRoot\$LogName-CMTRACE.log"
$LogParamsCMTrace = @{Path = $LogFileCMTrace; Component = $LogComponent; CMTrace = $true; WriteBackToHost = $true } # Messages will be written to the log and to the prompt
#endregion DECLARATION

#region TESTING
Write-Log @LogParams -Message "This is an Information message"
Write-Log @LogParams -Message "This is a Debug message" -Type Debug
Write-Log @LogParams -Message "This is a Verbose message" -Type Verbose
Write-Log @LogParams -Message "This is a Warning message" -Type Warning
Write-Log @LogParams -Message "This is an Error message" -Type Error

Write-Log @LogParamsCMTrace -Message "This Information message is written to a log file in CMTrace format"
Write-Log @LogParamsCMTrace -Message "This Debug message is written to a log file in CMTrace format" -Type Debug
Write-Log @LogParamsCMTrace -Message "This Verbose message is written to a log file in CMTrace format" -Type Verbose
Write-Log @LogParamsCMTrace -Message "This Warning message is written to a log file in CMTrace format" -Type Warning
Write-Log @LogParamsCMTrace -Message "This Error is written to a log file in CMTrace format" -Type Error
#region TESTING