/*
 * This file is part of THESIAS
 * Copyright (C) 2004-2020 David-Alexandre Trégouët, Valérie Garelle
 * All rights reserved.
 *
 * 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/>.
 */

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.JEditorPane;
import javax.swing.text.Document;
import javax.swing.text.PlainDocument;
import javax.swing.text.View;
import javax.swing.text.html.HTMLDocument;

public class DocumentRenderer implements Printable {

  protected int currentPage = -1;              
  protected JEditorPane jeditorPane;           
  protected double pageEndY = 0;              
  protected double pageStartY = 0;             

  protected boolean scaleWidthToFit = true;     


  protected PageFormat pFormat;
  protected PrinterJob pJob;


  public DocumentRenderer() {
    pFormat = new PageFormat();
    pJob = PrinterJob.getPrinterJob();
  }


  public Document getDocument() {
    if (jeditorPane != null) return jeditorPane.getDocument();
    else return null;
  }


  public boolean getScaleWidthToFit() {
    return scaleWidthToFit;
  }


  public void pageDialog() {
    pFormat = pJob.pageDialog(pFormat);
  }


  public int print(Graphics graphics, PageFormat pageFormat, int pageIndex) {
    double scale = 1;
    Graphics2D graphics2D;
    View rootView;

    graphics2D = (Graphics2D) graphics;

    jeditorPane.setSize((int) pageFormat.getImageableWidth(),Integer.MAX_VALUE);
    jeditorPane.validate();

    rootView = jeditorPane.getUI().getRootView(jeditorPane);

    if ((scaleWidthToFit) && (jeditorPane.getMinimumSize().getWidth() >
    pageFormat.getImageableWidth())) {
      scale = pageFormat.getImageableWidth()/
      jeditorPane.getMinimumSize().getWidth();
      graphics2D.scale(scale,scale);
    }

    graphics2D.setClip((int) (pageFormat.getImageableX()/scale),
    (int) (pageFormat.getImageableY()/scale),
    (int) (pageFormat.getImageableWidth()/scale),
    (int) (pageFormat.getImageableHeight()/scale));

    if (pageIndex > currentPage) {
      currentPage = pageIndex;
      pageStartY += pageEndY;
      pageEndY = graphics2D.getClipBounds().getHeight();
    }

    graphics2D.translate(graphics2D.getClipBounds().getX(),
    graphics2D.getClipBounds().getY());

    Rectangle allocation = new Rectangle(0,
    (int) -pageStartY,
    (int) (jeditorPane.getMinimumSize().getWidth()),
    (int) (jeditorPane.getPreferredSize().getHeight()));

    if (printView(graphics2D,allocation,rootView)) {
      return Printable.PAGE_EXISTS;
    }
    else {
      pageStartY = 0;
      pageEndY = 0;
      currentPage = -1;
      return Printable.NO_SUCH_PAGE;
    }
  }


  public void print(HTMLDocument htmlDocument) {
    setDocument(htmlDocument);
    printDialog();
  }


  public void print(JEditorPane jedPane) {
    setDocument(jedPane);
    printDialog();
  }


  public void print(PlainDocument plainDocument) {
    setDocument(plainDocument);
    printDialog();
  }


  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");
      }
    }
  }

  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 {

      if (allocation.getBounds().getMaxY() >= clipRectangle.getY()) {
        pageExists = true;
        if ((allocation.getBounds().getHeight() > clipRectangle.getHeight()) &&
        (allocation.intersects(clipRectangle))) {
          view.paint(graphics2D,allocation);
        } else {
          if (allocation.getBounds().getY() >= clipRectangle.getY()) {
            if (allocation.getBounds().getMaxY() <= clipRectangle.getMaxY()) {
              view.paint(graphics2D,allocation);
            } else {
              if (allocation.getBounds().getY() < pageEndY) {
                pageEndY = allocation.getBounds().getY();
              }
            }
          }
        }
      }
    }
    return pageExists;
  }


  protected void setContentType(String type) {
    jeditorPane.setContentType(type);
  }


  public void setDocument(HTMLDocument htmlDocument) {
    jeditorPane = new JEditorPane();
    setDocument("text/html",htmlDocument);
  }


  public void setDocument(JEditorPane jedPane) {
    jeditorPane = new JEditorPane();
    setDocument(jedPane.getContentType(),jedPane.getDocument());
  }


  public void setDocument(PlainDocument plainDocument) {
    jeditorPane = new JEditorPane();
    setDocument("text/plain",plainDocument);
  }

  protected void setDocument(String type, Document document) {
    setContentType(type);
    jeditorPane.setDocument(document);
  }

  public void setScaleWidthToFit(boolean scaleWidth) {
    scaleWidthToFit = scaleWidth;
  }
}