Pattern Builder

DataTemplate.cs

public enum PdfPageSize 
{
    A0,
    A1,
    A2,
    A3,
    A4
}

public class DocumentPreferencesBuilder
{
    public DocumentMargins _margins {get;set;}
    
    public void DefaultDocumentMargins(DocumentMargins margins)
    {
        _margins = margins;
    }
    
    public void PageSize(PdfPageSize size)
    {
        _pdfReport.DataBuilder.DefaultPageSize(size.ToRectangle());
    }
}

DocumentPreferencesBuilder.cs

public class DocumentPreferencesBuilder
{
    readonly PdfReport _pdfReport;

    public DocumentPreferencesBuilder(PdfReport pdfReport)
    {
        _pdfReport = pdfReport;
    }
    
    public void DocumentMargins(DocumentMargins margins)
    {
        _pdfReport.DataBuilder.DefaultDocumentMargins(margins);
    }
}

PagesHeaderBuilder.cs

public class PagesHeaderBuilder
{
    readonly PdfReport _pdfReport;
    
    public PagesHeaderBuilder(PdfReport pdfReport)
    {
        _pdfReport = pdfReport;
    }
    
    public void InlineHeader(Action<InlineHeaderProviderBuilder> inlineHeaderProviderBuilder)
    {
        var builder = new InlineHeaderProviderBuilder();
        inlineHeaderProviderBuilder(builder);
        _pdfReport.DataBuilder.SetHeader(builder.InlineHeaderProvider);
    }
}

PdfReport.cs

public class PdfReport
{
    internal DataBuilder DataBuilder { set; get; }
    
    public PdfReport()
    {
        DataBuilder = new DataBuilder();
    }
    
    public PdfReport DocumentPreferences(Action<DocumentPreferencesBuilder> pdfRptPagePreferencesBuilder)
    {
        var builder = new DocumentPreferencesBuilder(this);
        pdfRptPagePreferencesBuilder(builder);
        return this;
    }
    
    public PdfReport PagesHeader(Action<PagesHeaderBuilder> pagesHeaderBuilder)
    {
        var builder = new PagesHeaderBuilder(this);
        pagesHeaderBuilder(builder);
        return this;
    }
}