package at.gv.egiz.pdfas.itext;

import java.awt.color.ICC_Profile;
import java.io.IOException;
import java.io.OutputStream;

import org.apache.commons.io.IOUtils;
import org.apache.commons.io.output.ByteArrayOutputStream;
import org.apache.log4j.Logger;

import com.lowagie.text.Document;
import com.lowagie.text.DocumentException;
import com.lowagie.text.Font;
import com.lowagie.text.PageSize;
import com.lowagie.text.Paragraph;
import com.lowagie.text.Rectangle;
import com.lowagie.text.pdf.BaseFont;
import com.lowagie.text.pdf.PdfArray;
import com.lowagie.text.pdf.PdfDictionary;
import com.lowagie.text.pdf.PdfICCBased;
import com.lowagie.text.pdf.PdfName;
import com.lowagie.text.pdf.PdfString;
import com.lowagie.text.pdf.PdfWriter;

public final class IText {
   
   private IText() {
   }
   
   private static final Logger LOG = Logger.getLogger(IText.class);
   
   private static final Font        DEFAULT_FONT                 = new Font(Font.HELVETICA, 12, Font.NORMAL);
   private static final String      DEFAULT_TTF_FONT_RESOURCE    = "DejaVuSansCondensed.ttf";
   private static final String      DEFAULT_ICC_PROFILE_RESOURCE = "srgb.profile";
   private static final Rectangle   DEFAULT_PAGE_SIZE            = PageSize.A4;
   private static final int[]       DEFAULT_MARGINS_MM           = { 25, 25, 25, 25 }; // top, right, bottom, left
   public  static final String      DEFAULT_FILENAME             = "text";
   
   private static       Font        DEFAULT_TTF_FONT;
   private static       PdfICCBased DEFAULT_ICC_COLOR_SPACE;
   
   static {
      try {
         byte[] ttfFontData = IOUtils.toByteArray(IText.class.getResourceAsStream(DEFAULT_TTF_FONT_RESOURCE));
         DEFAULT_TTF_FONT = new Font(BaseFont.createFont(DEFAULT_TTF_FONT_RESOURCE, BaseFont.WINANSI, true, true, ttfFontData, null));
      } catch (Exception e) {
         LOG.error(e);
         DEFAULT_TTF_FONT = DEFAULT_FONT; 
      }
      try {
         byte[] iccData = IOUtils.toByteArray(IText.class.getResourceAsStream(DEFAULT_ICC_PROFILE_RESOURCE));
         DEFAULT_ICC_COLOR_SPACE = new PdfICCBased(ICC_Profile.getInstance(iccData));
         DEFAULT_ICC_COLOR_SPACE.remove(PdfName.ALTERNATE);
      } catch (Exception e) {
         LOG.error(e);
         DEFAULT_ICC_COLOR_SPACE = null; 
      }
   }
   
   public static byte[] createPDF(String content, boolean pdfa) throws DocumentException, IOException {
      ByteArrayOutputStream baOut = new ByteArrayOutputStream();
      createPDF(content, pdfa, baOut);
      return baOut.toByteArray();
   }
   
   public static byte[] createPDF(String content) throws DocumentException, IOException {
      return createPDF(content, false);
   }


   private static void addContent(Document document, boolean pdfa, String content) throws DocumentException {
      Paragraph p = new Paragraph(content, pdfa ? DEFAULT_TTF_FONT : DEFAULT_FONT);
      document.add(p);
   }
   public static void createPDF(String content, OutputStream outputStream) throws DocumentException, IOException {
      createPDF(content, false, outputStream);
   }

   public static void createPDF(String content, boolean pdfa, OutputStream outputStream) throws DocumentException, IOException {
      final float factor = (float) 72 / (float) 25.4;
      Document document = new Document(
            DEFAULT_PAGE_SIZE,
            (float) DEFAULT_MARGINS_MM[3] * factor,     // left
            (float) DEFAULT_MARGINS_MM[1] * factor,     // right
            (float) DEFAULT_MARGINS_MM[0] * factor,     // top
            (float) DEFAULT_MARGINS_MM[2] * factor      // bottom
      );
      
      PdfWriter pdfWriter = PdfWriter.getInstance(document, outputStream);
      if (pdfa) {
         pdfWriter.setPDFXConformance(PdfWriter.PDFA1B);
      }
      document.open();
      if (pdfa) {
         PdfDictionary pdfOutputIntent = new PdfDictionary(PdfName.OUTPUTINTENT);
         pdfOutputIntent.put(PdfName.OUTPUTCONDITIONIDENTIFIER, new PdfString("sRGB IEC61966-2.1"));
         pdfOutputIntent.put(PdfName.INFO, new PdfString("sRGB IEC61966-2.1"));
         pdfOutputIntent.put(PdfName.S, PdfName.GTS_PDFA1);
         if (DEFAULT_ICC_COLOR_SPACE != null) {
            pdfOutputIntent.put(PdfName.DESTOUTPUTPROFILE, pdfWriter.addToBody(DEFAULT_ICC_COLOR_SPACE).getIndirectReference());
         }
         pdfWriter.getExtraCatalog().put(PdfName.OUTPUTINTENTS, new PdfArray(pdfOutputIntent));
      }
      addContent(document, pdfa, content);
      if (pdfa) {
         pdfWriter.createXmpMetadata();
      }
      document.close();
   }

}