package tutorial.chapter05;

import com.itextpdf.io.font.constants.StandardFonts;
import com.itextpdf.kernel.colors.ColorConstants;
import com.itextpdf.kernel.font.PdfFontFactory;
import com.itextpdf.kernel.geom.Rectangle;
import com.itextpdf.kernel.pdf.PdfDocument;
import com.itextpdf.kernel.pdf.PdfPage;
import com.itextpdf.kernel.pdf.PdfReader;
import com.itextpdf.kernel.pdf.PdfWriter;
import com.itextpdf.kernel.pdf.canvas.PdfCanvas;
import com.itextpdf.kernel.pdf.extgstate.PdfExtGState;
import com.itextpdf.layout.Document;
import com.itextpdf.layout.element.Paragraph;
import com.itextpdf.layout.properties.TextAlignment;
import com.itextpdf.layout.properties.VerticalAlignment;
import java.io.File;
import java.io.IOException;

/**
 * Simple adding content example.
 */
public class C05E03_AddContent {

    public static final String SRC = "src/main/resources/pdf/ufo.pdf";

    public static final String DEST = "results/chapter05/add_content.pdf";

    public static void main(String args[]) throws IOException {
        File file = new File(DEST);
        file.getParentFile().mkdirs();
        new C05E03_AddContent().manipulatePdf(SRC, DEST);
    }

    public void manipulatePdf(String src, String dest) throws IOException {

        //Initialize PDF document
        PdfDocument pdfDoc = new PdfDocument(new PdfReader(src), new PdfWriter(dest));

        Document document = new Document(pdfDoc);
        Rectangle pageSize;
        PdfCanvas canvas;
        int n = pdfDoc.getNumberOfPages();
        for (int i = 1; i <= n; i++) {
            PdfPage page = pdfDoc.getPage(i);
            pageSize = page.getPageSize();
            canvas = new PdfCanvas(page);
            //Draw header text
            canvas.beginText().setFontAndSize(PdfFontFactory.createFont(StandardFonts.HELVETICA), 7)
                    .moveText(pageSize.getWidth() / 2 - 24, pageSize.getHeight() - 10)
                    .showText("I want to believe")
                    .endText();
            //Draw footer line
            canvas.setStrokeColor(ColorConstants.BLACK)
                    .setLineWidth(.2f)
                    .moveTo(pageSize.getWidth() / 2 - 30, 20)
                    .lineTo(pageSize.getWidth() / 2 + 30, 20).stroke();
            //Draw page number
            canvas.beginText().setFontAndSize(PdfFontFactory.createFont(StandardFonts.HELVETICA), 7)
                    .moveText(pageSize.getWidth() / 2 - 7, 10)
                    .showText(String.valueOf(i))
                    .showText(" of ")
                    .showText(String.valueOf(n))
                    .endText();
            //Draw watermark
            Paragraph p = new Paragraph("CONFIDENTIAL").setFontSize(60);
            canvas.saveState();
            PdfExtGState gs1 = new PdfExtGState().setFillOpacity(0.2f);
            canvas.setExtGState(gs1);
            document.showTextAligned(p,
                    pageSize.getWidth() / 2, pageSize.getHeight() / 2,
                    pdfDoc.getPageNumber(page),
                    TextAlignment.CENTER, VerticalAlignment.MIDDLE, 45);
            canvas.restoreState();
        }

        pdfDoc.close();

    }
}