public class Kampagne_Brief{
    
    public string camId {get;set;}
    
    @InvocableMethod(Label = 'Kampagne_Brief' description='')  
    
    public static void Kampagne_Brief(List<Id> CampaignId) {
        
        string camName = [SELECT Id, Name FROM Campaign WHERE Id =: CampaignId.get(0) LIMIT 1].Name;
        String strDate = String.valueOf(System.now().dateGmt()); // FORMAT YYYY-MM-DD
        // String strDate = System.now().format('yyyyMMdd'); // FORMAT YYYYMMDD
        
        PageReference page = Page.Kampagne_Brief_PDF;
        
        page.getParameters().put('Id', CampaignId.get(0));
        
        string camId= page.getParameters().put('Id', CampaignId.get(0));
        // string camName = page.getParameters().put('Campaign.Name', CampaignId.get(0));
        Blob contentBlob = page.getContentAsPDF();
        
        ContentVersion cv = new ContentVersion();
        cv.VersionData = contentBlob;
        cv.Title = strDate + '_' + camName;
        //    cv.Title =  System.today().year() + '_' + System.today().month() + '_' + System.today().day() + '_' + 'Serienbrief_'+ camName;
        cv.PathOnClient =  strDate + '_' + camName + '.pdf';
        //    cv.PathOnClient =  System.today().year() + '_' + System.today().month()  + '_' + System.today().day() + '_' + 'Serienbrief.pdf';
        cv.Vertraulichkeitsstufe__c = 'Intern';
        cv.Dokumentenklasse__c ='Anderes Dokument (nicht aufbewahrungspflichtig)';
        insert cv;
        
        cv = [SELECT Id, ContentDocumentId FROM ContentVersion WHERE Id = :cv.Id LIMIT 1];
        
        ContentDocumentLink cdl = new ContentDocumentLink();
        cdl.ContentDocumentId = cv.ContentDocumentId;
        cdl.ShareType = 'I';
        cdl.LinkedEntityId = camId;
        insert cdl;
    }
}

@isTest 
public with sharing class Kampagnen_Brief_Test  {        
    static testmethod void contentDocumentTest()        {  
            
Campaign cam                        = new Campaign();
        cam.Name                            = 'Test Briefkampagne';
        cam.RecordTypeId                    = '0127a000001lOti';
        cam.IsActive                        = True;
        insert cam;

        
        ContentVersion cv = new ontentVersion();
        cv.Title = '2022-03-10_John Campaign';
        cv.PathOnClient = '2022-03-10_John Campaign.pdf';
        cv.VersionData = Blob.valueOf('Test Content');
        cv.IsMajorVersion = true;
        cv.Vertraulichkeitsstufe__c = 'Intern';
        cv.Dokumentenklasse__c ='Anderes Dokument (nicht aufbewahrungspflichtig)';
        Insert cv;
        ContentVersion contentVersion_2 = [SELECT Id, Title, ContentDocumentId 
                                           FROM ContentVersion WHERE Id = :cv.Id LIMIT 1];   
        ContentDocumentLink contentlink = new ContentDocumentLink();
        
        contentlink.contentdocumentid = contentVersion_2.contentdocumentid;
        contentlink.ShareType = 'V';
        insert contentlink;
        Kampagne_Brief KB = new Kampagne_Brief();             
        
    }
    
    
}