/*
 * Transparent part of text:
 * Create transparent text and highlight it with transparent rectangles
 * 
 * Use the "opacityfill" and "opacitystroke" options of create_gstate() to 
 * create an explicit graphics state with transparency settings. 
 * Place a transparent text line in two different ways. 
 * First use set_gstate() to set the explicit graphics state before placing the
 * text line. 
 * Second use the "gstate" option of fit_textline(). 
 * Output a Textflow with one word highlighted with a transparent rectangle
 * using the "gstate" suboption of the "matchbox" option of add_textflow().
 * Output a transparent Textflow with one word surrounded by the transparent
 * borders of a rectangle using the "gstate" suboption of the "matchbox" option
 * and the "gstate" option of add_textflow().
 *
 * Required software: PDFlib/PDFlib+PDI/PPS 9
 * Required data: image file
 */
package com.pdflib.cookbook.pdflib.textflow;

import com.pdflib.pdflib;
import com.pdflib.PDFlibException;

public class transparent_part_of_text
{
    public static void main (String argv[])
    {
        /* This is where the data files are. Adjust as necessary. */
        String searchpath = "../input";
        String outfile = "transparent_part_of_text.pdf";
        String title = "Transparent Part of Text";

        pdflib p = null;
        int exitcode = 0;
        
        String imagefile = "nesrin.jpg";
        
        String text, optlist, mopts, gopts, result;
        int image, gstate, font, tf = -1;
        
        try {
            p = new pdflib();

            p.set_option("searchpath={" + searchpath + "}");

            /* This means we must check return values of load_font() etc. */
            p.set_option("errorpolicy=return");

            if (p.begin_document(outfile, "") == -1)
                throw new Exception("Error: " + p.get_errmsg());

            p.set_info("Creator", "PDFlib Cookbook");
            p.set_info("Title", title);
            
            /* Load image */
            image = p.load_image("auto", imagefile, "");
            if (image == -1)
                throw new Exception("Error: " + p.get_errmsg());

            /* Load the font. */
            font = p.load_font("Helvetica-Bold", "unicode", "");
            if (font == -1)
                throw new Exception("Error: " + p.get_errmsg());
            
            /* Start page */
            p.begin_page_ext(0, 0, "width=a4.height height=a4.width");
            
            /* Draw a yellow background rectangle */
            p.setcolor("fill", "rgb", 1, 0.9, 0.58, 0);
            p.rect(0, 0, 842, 595);
            p.fill(); 
            
            /* Output a background image */
            p.fit_image(image, 50, 50, "");
            
            /* Save the current graphics state. The save/restore of the current
             * state is not necessarily required, but it will help you get back to
             * a graphics state without any transparency.
             */
            p.save();
            
            /* Create an extended graphics state with transparency set to 50%, using
             * create_gstate() with the "opacityfill" option set to 0.5.
             */
            gstate = p.create_gstate("opacityfill=.5");
            
            /* Apply the extended graphics state */
            p.set_gstate(gstate);
            
            /* Display some text which will be transparent according to the
             * graphics state set
             */
            p.setcolor("fill", "rgb", 1, 0.9, 0.58, 0);
            p.fit_textline("Page 1: My favorite holiday photo", 100, 100, 
                "font=" + font + " fontsize=40");
            
            /* Restore the current graphics state */
            p.restore();
            
            p.end_page_ext("");
            
            /* Start page */
            p.begin_page_ext(0, 0, "width=a4.height height=a4.width");
            
            /* Draw a yellow background rectangle */
            p.setcolor("fill", "rgb", 1, 0.9, 0.58, 0);
            p.rect(0, 0, 842, 595);
            p.fill(); 
            
            /* Output a background image */
            p.fit_image(image, 50, 50, "");
            
            
            /* ------------------------------
             * Output a transparent text line
             * ------------------------------
             */
            
            /* Create an explicit graphics state with the transparency for fill 
             * operations set to 40%
             */
            gstate = p.create_gstate("opacityfill=0.4");
            
            /* Display a text line with the explicit graphics state applied. The
             * text will appear transparent. 
             */
            optlist = 
                "font=" + font + " fontsize=40 " + 
                "fillcolor={rgb 1 0.9 0.58} " +
                "gstate=" + gstate;
            
            p.fit_textline("Page 2: My favorite holiday photo", 100, 470, 
                optlist);
            
            
            /* --------------------------------------------------------
             * Output a Textflow with the word "favorite" filled with a 
             * transparent rectangle
             * --------------------------------------------------------
             */
            
            /* Create an explicit graphics state with the transparency for fill
             * operations set to 40%
             */
            gstate = p.create_gstate("opacityfill=0.4");
            
            /* Define the general Textflow options */
            optlist =
                "fontname=Helvetica-Bold fontsize=30 encoding=unicode " +
                "leading=120% charref fillcolor={rgb 1 0.9 0.58} ";
            
            /* Add parts of the Textflow */
            text = "Here you can see my ";  
            tf = p.add_textflow(tf, text, optlist);
            if (tf == -1)
                throw new Exception("Error: " + p.get_errmsg());
            
            /* Use the "matchbox" option to define a matchbox rectangle to be 
             * filled on parts of the Textflow. To fill the rectangle 
             * transparently the matchbox is provided with the graphics state
             * created above.
             */
            mopts = "matchbox={name=mymatchbox boxheight={ascender descender}" +
                " fillcolor={rgb 1 0.9 0.58} gstate=" + gstate +
                " offsetleft=-4 offsetright=4 offsettop=4} ";
            
            /* Use the "gstate" option to apply the explicit graphics state
             * defined above
             */
            gopts = "gstate=" + gstate;
            
            /* Add a part of the Textflow with the "matchbox" and "gstate" 
             * options. That part of the text will be filled with a transparent
             * rectangle and will appear transparent.
             */
            text = "favorite";   
            tf = p.add_textflow(tf, text, optlist + mopts + gopts);
            if (tf == -1)
                throw new Exception("Error: " + p.get_errmsg());
            
            /* Define the "matchbox=end" option to end the matchbox */
            mopts = "matchbox=end ";
            
            /* Create another explicit graphics state with no transparency */
            gstate = p.create_gstate("opacityfill=1");
            
            /* Use the "gstate" option to apply the explicit graphics state
             * defined above
             */
            gopts = "gstate=" + gstate;
            
            /* Add parts of the text with the "matchbox=end" option applied.
             * The matchbox rectangle will end before the text to be added.
             * The text will not appear transparent any more.
             */
            text = " holiday photo.";
            tf = p.add_textflow(tf, text, optlist + mopts + gopts);
            if (tf == -1)
                throw new Exception("Error: " + p.get_errmsg());
            
            result = p.fit_textflow(tf, 100, 200, 300, 400, "");
            if (!result.equals("_stop"))
            {
                /* Check for errors or more text to be placed */
            }
            p.delete_textflow(tf);
            
            
            /* -----------------------------------------------------------------
             * Output a transparent Textflow with the word "favorite" surrounded
             * by the transparent borders of a rectangle.
             * -----------------------------------------------------------------
             */
            tf = -1;
            
            /* Create an explicit graphics state with transparency for stroking
             * and filling set to 40%
             */
            gstate = p.create_gstate("opacitystroke=0.4 opacityfill=0.4");
            
            /* Define the general Textflow options including the graphics state
             * defined above
             */
            optlist =
                "fontname=Helvetica-Bold fontsize=30 encoding=unicode " +
                "leading=120% charref fillcolor={rgb 1 0.9 0.58} " +
                "gstate=" + gstate;
            
            /* Add parts of the Textflow */
            text = "This is my ";  
            tf = p.add_textflow(tf, text, optlist);
            if (tf == -1)
                throw new Exception("Error: " + p.get_errmsg());
            
            /* Use the "matchbox" option for defining a matchbox rectangle to be 
             * stroked around parts of the Textflow. To stroke the rectangle 
             * transparently the matchbox is provided with the graphics state 
             * created above.
             */
            mopts = " matchbox={name=mymatchbox gstate=" + gstate + 
                " boxheight={ascender descender} linecap=projecting" +
                    " borderwidth=3 strokecolor={rgb 1 0.9 0.58}" +
                " offsetleft=-4 offsetright=4 offsettop=4}";
            
            /* Add a part of the Textflow with the matchbox option */
            text = "favorite";   
            tf = p.add_textflow(tf, text, optlist + mopts);
            if (tf == -1)
                throw new Exception("Error: " + p.get_errmsg());
            
            /* Define the "matchbox=end" option to end the matchbox */
            mopts = " matchbox=end";
            
            /* Add parts of the text with the "matchbox=end" option.
             * The matchbox rectangle will end before the text to be added.
             */
            text = " holiday photo.";
            tf = p.add_textflow(tf, text, optlist + mopts);
            if (tf == -1)
                throw new Exception("Error: " + p.get_errmsg());
            
            result = p.fit_textflow(tf, 650, 100, 780, 280, "");
            if (!result.equals("_stop"))
            {
                /* Check for errors or more text to be placed */
            }
            p.delete_textflow(tf);
     
            p.end_page_ext("");

            p.end_document("");

        } catch (PDFlibException e) {
            System.err.println("PDFlib exception occurred:");
            System.err.println("[" + e.get_errnum() + "] " + e.get_apiname() +
                ": " + e.get_errmsg());
            exitcode = 1;
        } catch (Exception e) {
            System.err.println(e.toString());
            exitcode = 1;
        } finally {
            if (p != null) {
                p.delete();
            }
            System.exit(exitcode);
        }
    }
}