[CmdletBinding()]
param(
    [Parameter(Mandatory = $true)]
    [string]$SiteUrl,

    [Parameter(Mandatory = $true)]
    [string]$ListTitle,

    [Parameter(Mandatory = $true)]
    [string]$ExpiryFieldInternalName,

    [Guid]$FieldCustomizerComponentId = 'a555f4fc-d6a6-4421-8189-457449d9bbde'
)

$isapiPath = Join-Path ([Environment]::GetFolderPath('CommonProgramFiles')) 'microsoft shared\Web Server Extensions\16\ISAPI'
Add-Type -Path (Join-Path $isapiPath 'Microsoft.SharePoint.Client.Runtime.dll')
Add-Type -Path (Join-Path $isapiPath 'Microsoft.SharePoint.Client.dll')

$context = New-Object Microsoft.SharePoint.Client.ClientContext($SiteUrl)
$context.Credentials = [System.Net.CredentialCache]::DefaultNetworkCredentials

try {
    $list = $context.Web.Lists.GetByTitle($ListTitle)
    $field = $list.Fields.GetByInternalNameOrTitle($ExpiryFieldInternalName)
    $customActions = $list.UserCustomActions
    $context.Load($list)
    $context.Load($field)
    $context.Load($customActions)
    $context.ExecuteQuery()

    if ($field.InternalName -ne $ExpiryFieldInternalName) {
        Write-Warning "Das Feld wurde über seinen Anzeigenamen gefunden. Verwende künftig den internen Namen '$($field.InternalName)'."
    }

    $alreadyBound = $field.ClientSideComponentId -eq $FieldCustomizerComponentId
    $field.ClientSideComponentId = $FieldCustomizerComponentId
    if (-not $alreadyBound -or [string]::IsNullOrWhiteSpace($field.ClientSideComponentProperties)) {
        $field.ClientSideComponentProperties = (@{
            expiryField = $field.InternalName
        } | ConvertTo-Json -Compress)
    }
    $field.Update()

    # Remove the temporary list-scoped command registration used by older
    # diagnostic scripts. The app feature owns the production registration.
    $customActions | Where-Object {
        $_.Name -eq 'ExpiryIndicator.CommandSet'
    } | ForEach-Object {
        $_.DeleteObject()
    }

    $context.ExecuteQuery()

    Write-Host "ExpiryIndicator wurde für '$($list.Title)' an '$($field.InternalName)' gebunden."
}
finally {
    $context.Dispose()
}