content: package com.japisoft.editix.action.file;
  
  import java.awt.Graphics;
  import java.awt.Graphics2D;
  import java.awt.Rectangle;
  import java.awt.Shape;
  import java.awt.print.PageFormat;
  import java.awt.print.Printable;
  import java.awt.print.PrinterException;
  import java.awt.print.PrinterJob;
  
  import javax.swing.JComponent;
  import javax.swing.JEditorPane;
  import javax.swing.text.Document;
  import javax.swing.text.PlainDocument;
  import javax.swing.text.View;
  import javax.swing.text.html.HTMLDocument;
  
  import com.japisoft.editix.ui.EditixFrame;
  
  /**
  This program is available under two licenses : 
  
  1. For non commercial usage : 
  
  This program is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation, either version 3 of the License, or
  (at your option) any later version.
  
  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.
  
  You should have received a copy of the GNU General Public License
  along with this program.  If not, see <http://www.gnu.org/licenses/>.
  
  2. For commercial usage :
  
  You need to get a commercial license for source usage at : 
  
  http://www.editix.com/buy.html
  
  Copyright (c) 2018 Alexandre Brillant - JAPISOFT SARL - http://www.japisoft.com
  
  @author Alexandre Brillant - abrillant@japisoft.com
  @author JAPISOFT SARL - http://www.japisoft.com
  
  */
  public class DocumentRenderer implements Printable {
  	/*  DocumentRenderer prints objects of type Document. Text attributes, including
  	    fonts, color, and small icons, will be rendered to a printed page.
  	    DocumentRenderer computes line breaks, paginates, and performs other
  	    formatting.
  	
  	    An HTMLDocument is printed by sending it as an argument to the
  	    print(HTMLDocument) method. A PlainDocument is printed the same way. Other
  	    types of documents must be sent in a JEditorPane as an argument to the
  	    print(JEditorPane) method. Printing Documents in this way will automatically
  	    display a print dialog.
  	
  	    As objects which implement the Printable Interface, instances of the
  	    DocumentRenderer class can also be used as the argument in the setPrintable
  	    method of the PrinterJob class. Instead of using the print() methods
  	    detailed above, a programmer may gain access to the formatting capabilities
  	    of this class without using its print dialog by creating an instance of
  	    DocumentRenderer and setting the document to be printed with the
  	    setDocument() or setJEditorPane(). The Document may then be printed by
  	    setting the instance of DocumentRenderer in any PrinterJob.
  	*/
  	protected int currentPage = -1; //Used to keep track of when
  	//the page to print changes.
  
  	protected JEditorPane jeditorPane; //Container to hold the
  	//Document. This object will
  	//be used to lay out the
  	//Document for printing.
  
  	protected double pageEndY = 0; //Location of the current page
  	//end.
  
  	protected double pageStartY = 0; //Location of the current page
  	//start.
  
  	protected boolean scaleWidthToFit = true; //boolean to allow control over
  	//whether pages too wide to fit
  	//on a page will be scaled.
  
  	/*    The DocumentRenderer class uses pFormat and pJob in its methods. Note
  	      that pFormat is not the variable name used by the print method of the
  	      DocumentRenderer. Although it would always be expected to reference the
  	      pFormat object, the print method gets its PageFormat as an argument.
  	*/
  	protected PageFormat pFormat;
  	protected PrinterJob pJob;
  
  	/*  The constructor initializes the pFormat and PJob variables.
  	*/
  	public DocumentRenderer() {
  		pFormat = new PageFormat();
  		pJob = PrinterJob.getPrinterJob();
  	}
  
  	/*  Method to get the current Document
  	*/
  	public Document getDocument() {
  		if (jeditorPane != null)
  			return jeditorPane.getDocument();
  		else
  			return null;
  	}
  
  	/*  Method to get the current choice the width scaling option.
  	*/
  	public boolean getScaleWidthToFit() {
  		return scaleWidthToFit;
  	}
  
  	/*  pageDialog() displays a page setup dialog.
  	*/
  	public void pageDialog() {
  		pFormat = pJob.pageDialog(pFormat);
  	}
  
  	/*  The print method implements the Printable interface. Although Printables
  	    may be called to render a page more than once, each page is painted in
  	    order. We may, therefore, keep track of changes in the page being rendered
  	    by setting the currentPage variable to equal the pageIndex, and then
  	    comparing these variables on subsequent calls to this method. When the two
  	    variables match, it means that the page is being rendered for the second or
  	    third time. When the currentPage differs from the pageIndex, a new page is
  	    being requested.
  	
  	    The highlights of the process used print a page are as follows:
  	
  	    I.    The Graphics object is cast to a Graphics2D object to allow for
  	          scaling.
  	    II.   The JEditorPane is laid out using the width of a printable page.
  	          This will handle line breaks. If the JEditorPane cannot be sized at
  	          the width of the graphics clip, scaling will be allowed.
  	    III.  The root view of the JEditorPane is obtained. By examining this root
  	          view and all of its children, printView will be able to determine
  	          the location of each printable element of the document.
  	    IV.   If the scaleWidthToFit option is chosen, a scaling ratio is
  	          determined, and the graphics2D object is scaled.
  	    V.    The Graphics2D object is clipped to the size of the printable page.
  	    VI.   currentPage is checked to see if this is a new page to render. If so,
  	          pageStartY and pageEndY are reset.
  	    VII.  To match the coordinates of the printable clip of graphics2D and the
  	          allocation rectangle which will be used to lay out the views,
  	          graphics2D is translated to begin at the printable X and Y
  	          coordinates of the graphics clip.
  	    VIII. An allocation Rectangle is created to represent the layout of the
  	          Views.
  	
  	          The Printable Interface always prints the area indexed by reference
  	          to the Graphics object. For instance, with a standard 8.5 x 11 inch
  	          page with 1 inch margins the rectangle X = 72, Y = 72, Width = 468,
  	          and Height = 648, the area 72, 72, 468, 648 will be painted regardless
  	          of which page is actually being printed.
  	
  	          To align the allocation Rectangle with the graphics2D object two
  	          things are done. The first step is to translate the X and Y
  	          coordinates of the graphics2D object to begin at the X and Y
  	          coordinates of the printable clip, see step VII. Next, when printing
  	          other than the first page, the allocation rectangle must start laying
  	          out in coordinates represented by negative numbers. After page one,
  	          the beginning of the allocation is started at minus the page end of
  	          the prior page. This moves the part which has already been rendered to
  	          before the printable clip of the graphics2D object.
  	
  	    X.    The printView method is called to paint the page. Its return value
  	          will indicate if a page has been rendered.
  	
  	    Although public, print should not ordinarily be called by programs other
  	    than PrinterJob.
  	*/
  	public int print(Graphics graphics, PageFormat pageFormat, int pageIndex) {
  		
  		if ( jeditorPane == null ) {
  			
  			EditixFrame.THIS.printAll( graphics );
  			
  			return 0;
  			
  		} else {
  		
  			double scale = 1.0;
  			Graphics2D graphics2D;
  			View rootView;
  			//  I
  			graphics2D = (Graphics2D) graphics;
  			//  II
  			jeditorPane.setSize(
  				(int) pageFormat.getImageableWidth(),
  				Integer.MAX_VALUE);
  			jeditorPane.validate();
  			//  III
  			rootView = jeditorPane.getUI().getRootView(jeditorPane);
  			//  IV
  			if ((scaleWidthToFit)
  				&& (jeditorPane.getMinimumSize().getWidth()
  					> pageFormat.getImageableWidth())) {
  				scale =
  					pageFormat.getImageableWidth()
  						/ jeditorPane.getMinimumSize().getWidth();
  				graphics2D.scale(scale, scale);
  			}
  			//  V
  			graphics2D.setClip(
  				(int) (pageFormat.getImageableX() / scale),
  				(int) (pageFormat.getImageableY() / scale),
  				(int) (pageFormat.getImageableWidth() / scale),
  				(int) (pageFormat.getImageableHeight() / scale));
  			//  VI
  			if (pageIndex > currentPage) {
  				currentPage = pageIndex;
  				pageStartY += pageEndY;
  				pageEndY = graphics2D.getClipBounds().getHeight();
  			}
  			//  VII
  			graphics2D.translate(
  				graphics2D.getClipBounds().getX(),
  				graphics2D.getClipBounds().getY());
  			//  VIII
  			Rectangle allocation =
  				new Rectangle(
  					0,
  					(int) - pageStartY,
  					(int) (jeditorPane.getMinimumSize().getWidth()),
  					(int) (jeditorPane.getPreferredSize().getHeight()));
  			//  X
  			if (printView(graphics2D, allocation, rootView)) {
  				return Printable.PAGE_EXISTS;
  			} else {
  				pageStartY = 0;
  				pageEndY = 0;
  				currentPage = -1;
  				return Printable.NO_SUCH_PAGE;
  			}
  			
  		}
  	}
  
  	/*  print(HTMLDocument) is called to set an HTMLDocument for printing.
  	*/
  	public void print(HTMLDocument htmlDocument) {
  		setDocument(htmlDocument);
  		printDialog();
  	}
  
  	/*  print(JEditorPane) prints a Document contained within a JEDitorPane.
  	*/
  	public void print(JEditorPane jedPane) {
  		setDocument(jedPane);
  		printDialog();
  	}
  
  	/*  print(PlainDocument) is called to set a PlainDocument for printing.
  	*/
  	public void print(PlainDocument plainDocument) {
  		setDocument(plainDocument);
  		printDialog();
  	}
  
  	/*  A protected method, printDialog(), displays the print dialog and initiates
  	    printing in response to user input.
  	*/
  	protected void printDialog() {
  		if (pJob.printDialog()) {
  			pJob.setPrintable(this, pFormat);
  			try {
  				pJob.print();
  			} catch (PrinterException printerException) {
  				pageStartY = 0;
  				pageEndY = 0;
  				currentPage = -1;
  				System.out.println("Error Printing Document");
  			}
  		}
  	}
  
  	/*  printView is a recursive method which iterates through the tree structure
  	    of the view sent to it. If the view sent to printView is a branch view,
  	    that is one with children, the method calls itself on each of these
  	    children. If the view is a leaf view, that is a view without children which
  	    represents an actual piece of text to be painted, printView attempts to
  	    render the view to the Graphics2D object.
  	
  	    I.    When any view starts after the beginning of the current printable
  	          page, this means that there are pages to print and the method sets
  	          pageExists to true.
  	    II.   When a leaf view is taller than the printable area of a page, it
  	          cannot, of course, be broken down to fit a single page. Such a View
  	          will be printed whenever it intersects with the Graphics2D clip.
  	    III.  If a leaf view intersects the printable area of the graphics clip and
  	          fits vertically within the printable area, it will be rendered.
  	    IV.   If a leaf view does not exceed the printable area of a page but does
  	          not fit vertically within the Graphics2D clip of the current page, the
  	          method records that this page should end at the start of the view.
  	          This information is stored in pageEndY.
  	*/
  	protected boolean printView(
  		Graphics2D graphics2D,
  		Shape allocation,
  		View view) {
  		boolean pageExists = false;
  		Rectangle clipRectangle = graphics2D.getClipBounds();
  		Shape childAllocation;
  		View childView;
  
  		if (view.getViewCount() > 0) {
  			for (int i = 0; i < view.getViewCount(); i++) {
  				childAllocation = view.getChildAllocation(i, allocation);
  				if (childAllocation != null) {
  					childView = view.getView(i);
  					if (printView(graphics2D, childAllocation, childView)) {
  						pageExists = true;
  					}
  				}
  			}
  		} else {
  			//  I
  			if (allocation.getBounds().getMaxY() >= clipRectangle.getY()) {
  				pageExists = true;
  				//  II
  				if ((allocation.getBounds().getHeight()
  					> clipRectangle.getHeight())
  					&& (allocation.intersects(clipRectangle))) {
  					view.paint(graphics2D, allocation);
  				} else {
  					//  III
  					if (allocation.getBounds().getY()
  						>= clipRectangle.getY()) {
  						if (allocation.getBounds().getMaxY()
  							<= clipRectangle.getMaxY()) {
  							view.paint(graphics2D, allocation);
  						} else {
  							//  IV
  							if (allocation.getBounds().getY() < pageEndY) {
  								pageEndY = allocation.getBounds().getY();
  							}
  						}
  					}
  				}
  			}
  		}
  		return pageExists;
  	}
  
  	/*  Method to set the content type the JEditorPane.
  	*/
  	protected void setContentType(String type) {
  		if ( type == null )
  			type = "text/plain";
  		jeditorPane.setContentType(type);
  	}
  
  	/*  Method to set an HTMLDocument as the Document to print.
  	*/
  	public void setDocument(HTMLDocument htmlDocument) {
  		jeditorPane = new JEditorPane();
  		setDocument("text/html", htmlDocument);
  	}
  
  	/*  Method to set the Document to print as the one contained in a JEditorPane.
  	    This method is useful when Java does not provide direct access to a
  	    particular Document type, such as a Rich Text Format document. With this
  	    method such a document can be sent to the DocumentRenderer class enclosed
  	    in a JEditorPane.
  	*/
  	public void setDocument(JEditorPane jedPane) {
  		jeditorPane = new JEditorPane();
  		setDocument(jedPane.getContentType(), jedPane.getDocument());
  	}
  
  	/*  Method to set a PlainDocument as the Document to print.
  	*/
  	public void setDocument(PlainDocument plainDocument) {
  		jeditorPane = new JEditorPane();
  		setDocument("text/plain", plainDocument);
  	}
  
  	/*  Method to set the content type and document of the JEditorPane.
  	*/
  	protected void setDocument(String type, Document document) {
  		setContentType(type);
  		jeditorPane.setDocument(document);
  	}
  
  	/*  Method to set the current choice of the width scaling option.
  	*/
  	public void setScaleWidthToFit(boolean scaleWidth) {
  		scaleWidthToFit = scaleWidth;
  	}
  	
  	class ComponentPrintable implements Printable {
  		
  		private JComponent component;
  		
  		public ComponentPrintable( JComponent component ) {
  			this.component = component;
  		}
  		
  		@Override
  		public int print(
  			Graphics graphics, 
  			PageFormat pf, 
  			int pageIndex) throws PrinterException {
  			
  			component.paint( graphics );
  			
  			return 0;
  		}
  	}
  }
  