/*********************************************************************************************
                          Muhimbi PDF Converter - Dynamic Watermarking
 
              Copyright 2010, Muhimbi Ltd - www.muhimbi.com - All rights reserved
 
 The following code shows a simple way of adding a dynamic watermark to existing PDF Files. 
 The watermark content is read from a SharePoint column and rendered on the center of the page.
 Error and permission checking as well as other minor features have been omitted for the sake 
 of brevity and clarity.
 
 Ideally PDF Conversion, applying security and watermarking is executed in the same step, see 
 http://www.muhimbi.com/blog/2010/01/configure-pdf-security-from-sharepoint.html
 
 This code requires Muhimbi’s PDF Converter and Workflow Power Pack to be installed.
**********************************************************************************************/

using System.Drawing;
using System.IO;
using Syncfusion.Pdf;
using Syncfusion.Pdf.Parsing;
using Syncfusion.Pdf.Graphics;
using Muhimbi.SharePoint.DocumentConverter.PDF;
using Syncfusion.Pdf.Security;
            
SPFile spSourceDocument = MyWorkflow.Item.File;

string destinationFileName = spSourceDocument.Name;
string destinationFolderName = MyWorkflow.Parameter1 as string;

// ** Read the text from the Column named 'Watermark', use a column name of your choice.
string watermark = MyWorkflow.Item["Watermark"] as string;
string pdfOwnerPassword = "some!Strong^Password";

// ** z-order and transparency of the watermark
bool watermarkInBackground = true;
float watermarkTransparancy = 0.25f;

// ** Method for creating a simple template, amend as needed
WorkflowFunction<string, PdfTemplate> CreateWatermark = delegate(string[] parameters)
{
    const float watermarkWidth = 250;
    const float watermarkHeight = 23;
    string watermarkText = parameters[0];

    if(watermarkText==null)
        watermarkText = "no watermark specified";

    // ** Create a new Template
    PdfTemplate template = new PdfTemplate(watermarkWidth, watermarkHeight);
    PdfGraphics tg = template.Graphics;

    // ** Rectangle
    PdfPen pen = new PdfPen(PdfBrushes.Black, 1);
    tg.DrawRectangle(pen, PdfBrushes.White, new RectangleF(0, 0, watermarkWidth, watermarkHeight));

    // ** Evaluation message text
    using (Font f = new Font("Arial", 10f, FontStyle.Regular))
    {
        PdfFont font = new PdfTrueTypeFont(f, false);
        PdfStringFormat stringFormat = new PdfStringFormat();
        stringFormat.Alignment = PdfTextAlignment.Center;
        stringFormat.LineAlignment = PdfVerticalAlignment.Middle;
        stringFormat.WordWrap = PdfWordWrapType.WordOnly;
        stringFormat.ClipPath = true;
        tg.DrawString(watermarkText, font, PdfBrushes.Black, new RectangleF(5, 0, watermarkWidth - 10, watermarkHeight), stringFormat);
    }

    return template;
};

// ** Method for applying security settings, amend / uncomment as needed
WorkflowMethod<PdfLoadedDocument> ApplySecurity = delegate(PdfLoadedDocument[] pdfDocuments)
{
    PdfLoadedDocument pdfDocument = pdfDocuments[0];
    // ** Enable encryption of content
    pdfDocument.Security.KeySize = PdfEncryptionKeySize.Key128Bit;
    // ** Specify the password used for modifying permissions
    pdfDocument.Security.OwnerPassword = pdfOwnerPassword;

    // ** Apply the restrictions, if any. Note that by default nothing is 
    // ** allowed and we need to individually enable permissions
    pdfDocument.Security.Permissions = PdfPermissionsFlags.Default;
    // ** Allow Commenting / annotations
    pdfDocument.Security.SetPermissions(PdfPermissionsFlags.EditAnnotations);
    // ** Allow Accessibility
    //pdfDocument.Security.SetPermissions(PdfPermissionsFlags.AccessibilityCopyContent);
    // ** Allow Copy content via clipboard etc.
    //pdfDocument.Security.SetPermissions(PdfPermissionsFlags.CopyContent);
    // ** Allow Assemble / modification of document
    //pdfDocument.Security.SetPermissions(PdfPermissionsFlags.AssembleDocument);
    // ** Allow Form fields to be filled out
    pdfDocument.Security.SetPermissions(PdfPermissionsFlags.FillFields);
    // ** Allow high resolution printing
    pdfDocument.Security.SetPermissions(PdfPermissionsFlags.FullQualityPrint);
    // ** Allow any kind of printing
    pdfDocument.Security.SetPermissions(PdfPermissionsFlags.Print);
};

// ** Load the document from SharePoint
PdfLoadedDocument sourceDocument = new PdfLoadedDocument(spSourceDocument.OpenBinary());

// ** Restrict the rights
ApplySecurity(sourceDocument);

// ** Create the watermark Template
PdfTemplate watermarkTemplate = CreateWatermark(watermark);

// ** Iterate over all pages and apply the watermark
foreach (PdfPageBase page in sourceDocument.Pages)
{
    // ** Position the watermark at the centre of the page
    float wmWidth = watermarkTemplate.Width;
    float wmHeight = watermarkTemplate.Height;
    float wmLeft = ((page.Size.Width - wmWidth) / 2);
    float wmTop = ((page.Size.Height - wmHeight) / 2);
    PointF wmPosition = new PointF(wmLeft, wmTop);

    // ** Place watermark behind or in front of text?
    if (watermarkInBackground == true)
    {
        PdfTemplate pageTemplate = page.CreateTemplate();
        page.Layers.Clear();
        PdfGraphics g = page.Graphics;
        g.SetTransparency(watermarkTransparancy);
        g.DrawPdfTemplate(watermarkTemplate, wmPosition);
        g.SetTransparency(1f);
        g.DrawPdfTemplate(pageTemplate, PointF.Empty, page.Size);
    }
    else
    {
        PdfGraphics g = page.Graphics;
        g.SetTransparency(watermarkTransparancy);
        g.DrawPdfTemplate(watermarkTemplate, wmPosition);
    }
}

// ** Construct the path and file to write the watermarked PDF file to.
if (string.IsNullOrEmpty(destinationFolderName) == true)
    destinationFolderName = spSourceDocument.ParentFolder.Url;
SPFolder destinationFolder = Utility.GetSPFolder(destinationFolderName, MyWorkflow.Web);
string destinationFilePath = string.Format("{0}/{1}", destinationFolder.Url,
                                           destinationFileName);
SPWeb destinationWeb = destinationFolder.ParentWeb;
SPFile spDestinationFile = destinationWeb.GetFile(destinationFilePath);

// ** If a document library requires manual checkout and the file is not checked out, then 
// ** check the file out before uploading.
if (spDestinationFile.Exists && spDestinationFile.Item.ParentList.ForceCheckout &&
    spDestinationFile.CheckOutStatus == SPFile.SPCheckOutStatus.None)
{
    spDestinationFile.CheckOut();
}

// ** Add the file to the site including the meta data
using (MemoryStream watermarkedFile = new MemoryStream())
{
    sourceDocument.Save(watermarkedFile);
    spDestinationFile = destinationWeb.Files.Add(destinationFilePath, watermarkedFile,
                                                 spSourceDocument.Item.Properties, true);
}

// ** Check the file back in if this script was responsible for checking it out.
if (spDestinationFile.Item.ParentList.ForceCheckout == true)
{
    spDestinationFile.CheckIn("Auto check-in after PDF watermarking.");
}