powershell zip archiver script

#Program Name: ZipArchiver
#Programmer: Drake Owen
#Description: Zips all files within certain parameters input by the user.

#Parameters
param(
[string]$FilePath,
[string]$NameFilter, #Required #String
[string]$DateFilterType, #Required #String
[int]$DateFilterNum, #Required Number
[string]$ArcPath,
[string]$ArcName, #Required #String
[string]$ArcFileFreq,
[string]$ArcFileDateFormat
)

#if required parameters are not passed program will close
if (!$NameFilter -or !$DateFilterType -or !$ArcName -or !$DateFilterNum)
{
    exit
}

#Defines Default FilePath if not defined
if (!$FilePath)
{
    $FilePath = ".\"
}

#Converts days to weeks
if ($DateFilterType -eq "TW" -or $DateFilterType -eq "PW")
    {
        $DateFilterNum = (7 * $DateFilterNum) + $DateFilterNum
    }

#Declaring Variables
$today = (get-date) #get today's date
$fileList = (Get-ChildItem -path $FilePath -Filter $NameFilter) #gets list of files in directory
$PSversion = $PSVersionTable.PSVersion | sort-object major | ForEach-Object     {$_.major}

#Set Target Date
switch ($DateFilterType)
{
    TD {$targetdate = $today.AddDays(-$DateFilterNum)} #Total Days
    TW {$targetdate = $today.AddDays(-$DateFilterNum)} #Total Weeks
    TM {$targetdate = $today.AddMonths(-$DateFilterNum)} #Total Months
    PD
    {
        $newdate = $today.AddDays(1) #Previous Day
        $targetdate = $newdate.AddDays(-1 * $DateFilterNum)
    }
    PW
    {
        $newdate = New-Object System.DateTime $today.Year,$today.Month, 1 #Previous Month
        $targetdate = $newdate.AddDays(1 + (-1 * $DateFilterNum))
    }
    PM
    {
        $newdate = New-Object System.DateTime $today.Year,$today.Month, 1 #Previous Month
        $targetdate = $newdate.AddMonths(1 + (-1 * $DateFilterNum))
    }
}

#Loops Through All Files
foreach($file in $fileList)
{
    #Have to reset DestPath each time
    if(!$ArcPath)
    {
        $destPath = Join-Path -Path ".\" -Childpath $ArcName #Default destination filepath
    }
    else
    {
        $destPath = Join-Path -Path $ArcPath -Childpath $ArcName
    }

    $dateFormat = $File.CreationTime.ToString($ArcFileDateFormat)

    #Naming the arc file based on date format
        if ($ArcFileFreq -eq "Y" -or $ArcFileFreq -eq "M")
    {
        $destPath = [string]::Format($destPath, $dateFormat) #Formatting date of Arc File
    }

    #If arc file is made quarterly
    elseif ($ArcFileFreq -eq "Q")
    {
        #Calculating Quarter
        switch ($file.CreationTime.Month) {
            1 {$quarterNum = "1"}
            2 {$quarterNum = "1"}
            3 {$quarterNum = "1"}
            4 {$quarterNum = "2"}
            5 {$quarterNum = "2"}
            6 {$quarterNum = "2"}
            7 {$quarterNum = "3"}
            8 {$quarterNum = "3"}
            9 {$quarterNum = "3"}
            10 {$quarterNum = "4"}
            11 {$quarterNum = "4"}
            12 {$quarterNum = "4"}
            Default {$quarterNum = "1"}
        }

        $destPath = [string]::Format($destPath, $dateFormat, $quarterNum) #Formating date of Arc File
    }

    #This is what actually zips stuff
    if($file.CreationTime -lt $targetdate)
    {
        $FullPath = Join-Path -path $FilePath -Childpath $file #Defines a fullpath used for the compress and remove commands
        if ($PSversion -lt 5)
        {
            #Zip fuction goes here.
        }
        else
        {
            compress-archive -Path $FullPath -Update -DestinationPath $destPath #This is what actually compresses and archives the files
        }
        Write-Host $file "Was Added to" $ArcName
        #Remove-Item -Path $FullPath #Deletes files after being zipped
    }
    else
    {
        Write-Host $file "Was not zipped |" "Created on:"$file.CreationTime
    }
    Write-Host "------------------------------------------------------------"
}