Autoscaling Storage Account File Share Size

# Variable Definitions
$subscription_id = "12345"
$resource_group = "SA"
$storage_account_name = "AVDFSLogix01"
$file_share_names = @("profiles01", "offiprofiles01")

# Connect to Azure and Import Az Module
# Connect-AzAccount
Import-Module -Name Az.Accounts
Import-Module -Name Az.Storage
Set-AzContext -SubscriptionId $subscription_id

# Get storage account SKU to Determine minimum size
$storageAccountType = (Get-AzStorageAccount -ResourceGroupName $resource_group -Name $storage_account_name).Sku.Name

foreach ($file_share_name in $file_share_names) {
    # Get storage account object
    $storageAccount = Get-AzStorageAccount -ResourceGroupName $resource_group -Name $storage_account_name
    
    # Get file share
    $StorageContext = New-AzStorageContext -StorageAccountName $storage_account_name -Anonymous
    $PFS = Get-AzRmStorageShare -ResourceGroupName $resource_group -StorageAccountName $storage_account_name -Name $file_share_name -GetShareUsage
    
    # Get provisioned capacity and used capacity
    $ProvisionedCapacity = $PFS.QuotaGiB
    $UsedCapacityBytes = $PFS.ShareUsageBytes
    # Convert used capacity to GB for easier comparison
    $UsedCapacityGB = [Math]::Round($UsedCapacityBytes / ([Math]::Pow(2, 30)), 2)
    
    Write-Host "Provisioned Capacity for ${file_share_name} (GiB):" $ProvisionedCapacity
    Write-Host "Share Usage for ${file_share_name} (GB):" $UsedCapacityGB
   
    #By changing the denominator in the formula from 0.8 (which represents 20% free space, as 100% - 20% = 80% or 0.8) to a value that reflects your desired threshold of free space, you can adjust the threshold. 
    #For 30% free space, the calculation should use 0.7 (since 100% - 30% = 70% or 0.7).
    # Calculate required capacity to maintain exactly 20% free space. Increases or Decreases based on used capacity.
    $RequiredCapacity = [Math]::Ceiling(($UsedCapacityBytes / ([Math]::Pow(2, 30))) / 0.8)

    # Adjust for minimum size based on SKU
    if ($storageAccountType.StartsWith("Premium")) {
        $RequiredCapacity = [Math]::Max($RequiredCapacity, 100)
    }
    elseif ($storageAccountType.StartsWith("Standard")) {
        $RequiredCapacity = [Math]::Max($RequiredCapacity, 1)
    }
    
    # Check if the current provisioned capacity is different from the required capacity
    if ($RequiredCapacity -ne $ProvisionedCapacity) {
        # Adjust the provisioned capacity
        Update-AzRmStorageShare -StorageAccount $storageAccount -Name $file_share_name -QuotaGiB $RequiredCapacity -Whatif
        Write-Host "Provisioned Capacity for ${file_share_name} adjusted to ${RequiredCapacity} GiB based on SKU requirements."
    }
    else {
        Write-Host "Provisioned Capacity for ${file_share_name} already meets 20% free space requirement and SKU requirements."
    }
}