package com.qoppa;

import java.io.FileInputStream;
import java.security.KeyStore;
import java.util.Enumeration;

import android.app.Activity;
import android.graphics.RectF;
import android.os.Bundle;
import android.util.Log;

import com.qoppa.android.pdf.SignatureAppearance;
import com.qoppa.android.pdf.SigningInformation;
import com.qoppa.android.pdf.form.SignatureField;
import com.qoppa.android.pdfProcess.PDFDocument;
import com.qoppa.android.pdfProcess.PDFPage;
import com.qoppa.android.pdfViewer.fonts.StandardFontTF;

public class SignSample extends Activity 
{
	public void onCreate(Bundle saveInstBundle)
	{
		super.onCreate(saveInstBundle);
       
		StandardFontTF.mAssetMgr = getAssets();

		try
		{
			//intializing a PDFDocument with no parameters creates a new document.  
			//use one of the the other constructors for PDFDocument to load an existent document.
			PDFDocument pdf = new PDFDocument();

			PDFPage page = pdf.appendNewPage(800, 1000);
			//add a field to sign.  if the document contains a signature field, it can be retrieved with
			//PDFDocument.getAcroForm().getSignatureFields()
			SignatureField field = page.addSignatureField("test", new RectF(100, 100, 500, 200));
   
			//path to a "p12" or "pfx" file
			String pfxLoc = "/sdcard/certificate.p12";
   			String pfxPassword = "thepassword";
   
   			FileInputStream pfxStream = new FileInputStream (pfxLoc);
  			//pfx files are a type pkcs12 files; keytore should be instantiated with "PKCS12" for both
			//.p12 files and .pfx files
  			KeyStore store = KeyStore.getInstance("PKCS12");
			store.load(pfxStream, pfxPassword.toCharArray());
   			pfxStream.close();
   			
			//An alias is required to sign the document.  
			String alias = "";
   			
			//If the alias for the keystore is not known, it can probably be determined with this code
			Enumeration<String> aliases =store.aliases();
			while(aliases.hasMoreElements())
			{
				String element = aliases.nextElement();
				if(!element.equals(""))
				{
					alias = element;
					break;
				}
			}
			
			//The appearance can be customized using the setters exposed by SignatureAppearance - these can 
			//be used to modify the text displayed, add an image background, etc...
			SignatureAppearance appearance = new SignatureAppearance();
                        
			SigningInformation signingInfo = new SigningInformation(store, alias, pfxPassword);
			signingInfo.setSignatureAppearance(appearance);

			//calling signDocument will sign the document and write it to the sdcard.
			//the 3rd parameter is the path the signed document will be saved to.
			pdf.signDocument(field, signingInfo, "/sdcard/signed.pdf");
			Log.e("Signing test","done signing");
		}
        	catch (Exception e)
		{
        		Log.e("error while signing", Log.getStackTraceString(e));
        	}
	}
}