function Import-PodFromSecretServer {
<#
.SYNOPSIS
    Import Pod Certificates from Secret Server.
#>
    [CmdletBinding()]
    param(
        [Parameter(Mandatory = $false)]
        $PodName,
        [Parameter(Mandatory = $false, ParameterSetName = "credentials")]
        [string]$SecretServerUrl ="https://alkami.secretservercloud.com",
        [Parameter(Mandatory = $false, ParameterSetName = "credentials")]
        $SecretServerUserName,
        [Parameter(Mandatory = $false, ParameterSetName = "credentials")]
        $SecretServerPassword,
        [Parameter(Mandatory = $false)]
        [ValidateSet("Web", "App")]
        $ServerType,
        [Parameter(Mandatory = $false, HelpMessage = "ADGroups that need permission to these certificates")]
        [string[]]$ADGroups,
        [Parameter(Mandatory = $false)]
        $TempDirectory = "c:\temp\importTempDir",
        [Parameter(Mandatory = $false)]
        [string]$CertRoot = "Cert:\LocalMachine\",
        [Parameter(Mandatory = $false)]
        [switch]$UsePassword,
        [Parameter(Mandatory = $false)]
        [ValidateSet("Production", "Staging")]
        [string]$EnvironmentType
    )
    begin {
        Import-AWSModule # SSM

        New-Item -Path $TempDirectory -ItemType Directory -Force -ErrorAction SilentlyContinue | Out-Null

        switch ($EnvironmentType) {
            "Production" {$RootFolderName = "Production-CertApi"}
            "Staging" {$RootFolderName = "Staging-CertApi"}
        }

        # Get all parmeters which weren't supplied.
        if(!$EnvironmentType)
        {
            $EnvironmentType = Get-AppSetting Environment.Type
        }

        if(!$PodName)
        {
            $PodName = Get-AppSetting Environment.Name
        }

        if(!$ServerType)
        {
            $ServerType = Get-AppSetting Environment.Server
        }

        if((!$SecretServerUserName -or !$SecretServerPassword))
        {
            if(Test-IsAws)
            {
                if(!$SecretServerUserName) {
                    $SecretServerUserName = (Get-SSMParameter -Name "secret_server_api_username" -WithDecryption $true).Value
                }

                if(!$SecretServerPassword) {
                    $SecretServerPassword = (Get-SSMParameter -Name "secret_server_api_password" -WithDecryption $true).Value
                }
            }
            else {
                Write-Error "Secret credentials must be manually provided if this is run on a non-AWS machine. They cannot be retrieved from SSM."
            }
        }

        $secretServer = [SecretServerConnection]::new($SecretServerUrl, $SecretServerUserName, $SecretServerPassword)
        $UseTwoFactor = $false
        $secretServer.Authenticate($UseTwoFactor)

        $NameOfCertificateField = "pfx-file"
        $NameOfPasswordField = "Import Password"
        Add-Type -Assembly System.IO.Compression.FileSystem
    }
    process {
        $startTime = Get-Date
        Write-Debug "Getting folder info"
        $environmentFolderId = $secretServer.GetFolderIdByName($RootFolderName)
        $podFolderId = $secretServer.GetFolderIdByName($PodName, $environmentFolderId)
        $subFolderId = $secretServer.GetFolderIdByName($ServerType, $podFolderId) # Should be at an App/Mic/Web folder by this point. These folder names aren't unique, hence getting the environment folder id above.

        $storeFolders = $secretServer.GetChildFolders($subFolderId)

        $timeElapsed = New-TimeSpan -Start $startTime -End (Get-Date)
        Write-Debug "Folder info retreived - $timeElapsed"

        foreach ($storeFolder in $storeFolders) {
            if ($storeFolder.FolderName -eq "CertificateAuthority") {$sanitizedStore = "CA"} else {$sanitizedStore = $storeFolder.FolderName} # Powershell's Paths don't match the X509 enum. So here we do a poor man's lookup. If we ever need more stores than just the CA, this needs to be expanded to something more robust and clean.

            $TempStoreDirectory = Join-Path $TempDirectory $storeFolder.FolderName

            $installedCerts = (Get-Cert -StoreName $sanitizedStore).thumbprint # Get certs in the current store.

            Write-Debug "Getting Secrets and downloading certificate chain"
            $secretInfoList = $secretServer.GetSecretByFolderId($storeFolder.id)
            $secretInfoList | Where-Object {$installedCerts -notcontains $_.name.split("-")[-1]}
            foreach ($secretInfo in $secretInfoList) {
                $secret = $secretServer.GetSecretById($secretInfo.id)

                # Don't import expired certs
                $certExpirationDate = $secret.items | Where-Object {$_.fieldName -eq "ExperationDate"}
                if ((Get-Date $certExpirationDate.itemValue) -gt (Get-Date)) {
                    if ($installedCerts) { #Don't die if there are no certs
                        $secretThumbprint = $secret.items | Where-Object {$_.fieldName -eq "Thumbprint"} | Select-Object -ExpandProperty itemValue
                        if ($installedCerts.Contains($secretThumbprint)) {
                            Write-Verbose "Certificate with thumbprint $secretThumbprint already installed"
                            continue
                        }
                    }
                    if ($UsePassword) {
                        $TempPassword = $secret.items | Where-Object {$_.fieldName -eq $NameOfPasswordField} | Select-Object -ExpandProperty itemValue
                        $Password = ConvertTo-SecureString $TempPassword -AsPlainText -Force
                    }

                    $folder = Join-Path $TempStoreDirectory $secret.Name
                    Remove-Item $folder -Force -ea SilentlyContinue -Recurse
                    New-Item $folder -ItemType Directory -Force -ea SilentlyContinue | Out-Null

                    $zipFolder = $folder, "$($secret.Name).zip" -join "\"
                    if ($secretServer.DownloadFile($secret.Id, $NameOfCertificateField, $zipFolder)) {
                        $timeElapsed = New-TimeSpan -Start $startTime -End (Get-Date)
                        Write-Debug "downloaded... - $timeElapsed"

                        [System.IO.Compression.ZipFile]::ExtractToDirectory($zipFolder, $folder)
                        Write-Debug "unzipping complete - $timeElapsed"

                        $certificateFiles = Get-ChildItem $folder -Include "*.cer", "*.pfx" -Recurse
                        $certList = [System.Collections.Arraylist]::new()
                        foreach ($file in $certificateFiles) {
                            $certStore = if ($file.Directory.Name -Match $file.BaseName) {$sanitizedStore}else {$file.Directory.Name}

                            [void]$certList.Add(([PSObject]@{
                                        file      = $file
                                        certStore = Join-path $CertRoot $certStore
                                    }))
                        }

                        foreach ($cert in $certList) {
                            if ($cert.file.extension -eq ".cer") {
                                try {
                                    Import-Certificate -FilePath $cert.file.FullName -CertStoreLocation $cert.certStore | Out-null
                                }
                                catch {
                                    Write-Warning "Failed to import Cert with filename $($cert.file.FullName)"
                                    Write-Warning -Message "Error: $($_.Exception.ErrorRecord)"
                                    Write-Warning -Message "Stack Trace: $($_.Exception.StackTrace)"
                                }
                            }
                            else {
                                try {
                                    $installedCert = Import-PfxCertificate -FilePath $cert.file.FullName -CertStoreLocation $cert.certStore -Exportable -Password $Password
                                    foreach ($ADGroup in $ADGroups.Split("{,}")) {
                                        Write-Host "Setting Permissions"
                                        Set-CertPermissions -certThumprint $installedCert.Thumbprint -user $ADGroup | Out-Null
                                    }
                                }
                                catch [System.ComponentModel.Win32Exception] {
                                    Write-Warning "Failed to import Cert with filename $($cert.file.FullName)"
                                    Write-Warning -Message "Error: $($_.Exception.Message)"
                                    Write-Warning -Message "Stack Trace: $($_.Exception.StackTrace)"
                                }
                                catch {
                                    Write-Warning "Failed to import Cert with filename $($cert.file.FullName)"
                                    Write-Warning -Message "Error: $($_.Exception.ErrorRecord)"
                                    Write-Warning -Message "Stack Trace: $($_.Exception.StackTrace)"
                                }
                            }
                        }
                    }
                    else {
                        Write-Warning -Message "File could not be downloaded for certificate with thumbprint $($secretThumbprint)."
                    }
                }
            }
        }
    }
}