/*
 * Jalview - A Sequence Alignment Editor and Viewer (2.11.2.5)
 * Copyright (C) 2022 The Jalview Authors
 * 
 * This file is part of Jalview.
 * 
 * Jalview 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.
 *  
 * Jalview 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 Jalview.  If not, see <http://www.gnu.org/licenses/>.
 * The Jalview Authors are detailed in the 'AUTHORS' file.
 */
package org.jibble.epsgraphics;

import java.io.BufferedWriter;
import java.io.IOException;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.StringWriter;
import java.io.Writer;
import java.util.Date;

/**
 * This represents an EPS document. Several EpsGraphics2D objects may point to
 * the same EpsDocument.
 * <p>
 * Copyright Paul Mutton,
 * <a href="http://www.jibble.org/">http://www.jibble.org/</a>
 * 
 */
public class EpsDocument
{

  /**
   * Constructs an empty EpsDevice.
   */
  public EpsDocument(String title)
  {
    _title = title;
    minX = Float.POSITIVE_INFINITY;
    minY = Float.POSITIVE_INFINITY;
    maxX = Float.NEGATIVE_INFINITY;
    maxY = Float.NEGATIVE_INFINITY;
    _stringWriter = new StringWriter();
    _bufferedWriter = new BufferedWriter(_stringWriter);
  }

  /**
   * Constructs an empty EpsDevice that writes directly to a file. Bounds must
   * be set before use.
   */
  public EpsDocument(String title, OutputStream outputStream, int minX,
          int minY, int maxX, int maxY) throws IOException
  {
    _title = title;
    this.minX = minX;
    this.minY = minY;
    this.maxX = maxX;
    this.maxY = maxY;
    _bufferedWriter = new BufferedWriter(
            new OutputStreamWriter(outputStream));
    write(_bufferedWriter);
  }

  /**
   * Returns the title of the EPS document.
   */
  public synchronized String getTitle()
  {
    return _title;
  }

  /**
   * Updates the bounds of the current EPS document.
   */
  public synchronized void updateBounds(double x, double y)
  {
    if (x > maxX)
    {
      maxX = (float) x;
    }
    if (x < minX)
    {
      minX = (float) x;
    }
    if (y > maxY)
    {
      maxY = (float) y;
    }
    if (y < minY)
    {
      minY = (float) y;
    }
  }

  /**
   * Appends a line to the EpsDocument. A new line character is added to the end
   * of the line when it is added.
   */
  public synchronized void append(EpsGraphics2D g, String line)
  {
    if (_lastG == null)
    {
      _lastG = g;
    }
    else if (g != _lastG)
    {
      EpsGraphics2D lastG = _lastG;
      _lastG = g;
      // We are being drawn on with a different EpsGraphics2D context.
      // We may need to update the clip, etc from this new context.
      if (g.getClip() != lastG.getClip())
      {
        g.setClip(g.getClip());
      }
      if (!g.getColor().equals(lastG.getColor()))
      {
        g.setColor(g.getColor());
      }
      if (!g.getBackground().equals(lastG.getBackground()))
      {
        g.setBackground(g.getBackground());
      }
      // We don't need this, as this only affects the stroke and font,
      // which are dealt with separately later on.
      // if (!g.getTransform().equals(lastG.getTransform())) {
      // g.setTransform(g.getTransform());
      // }
      if (!g.getPaint().equals(lastG.getPaint()))
      {
        g.setPaint(g.getPaint());
      }
      if (!g.getComposite().equals(lastG.getComposite()))
      {
        g.setComposite(g.getComposite());
      }
      if (!g.getComposite().equals(lastG.getComposite()))
      {
        g.setComposite(g.getComposite());
      }
      if (!g.getFont().equals(lastG.getFont()))
      {
        g.setFont(g.getFont());
      }
      if (!g.getStroke().equals(lastG.getStroke()))
      {
        g.setStroke(g.getStroke());
      }
    }
    _lastG = g;

    try
    {
      _bufferedWriter.write(line + "\n");
    } catch (IOException e)
    {
      throw new EpsException("Could not write to the output file: " + e);
    }
  }

  /**
   * Outputs the contents of the EPS document to the specified Writer, complete
   * with headers and bounding box.
   */
  public synchronized void write(Writer writer) throws IOException
  {
    float offsetX = -minX;
    float offsetY = -minY;

    writer.write("%!PS-Adobe-3.0 EPSF-3.0\n");
    writer.write("%%Creator: Jalview "
            + jalview.bin.Cache.getProperty("VERSION") + " \n");
    writer.write("%%Title: " + _title + "\n");
    writer.write("%%CreationDate: " + new Date() + "\n");
    writer.write("%%BoundingBox: 0 0 " + ((int) Math.ceil(maxX + offsetX))
            + " " + ((int) Math.ceil(maxY + offsetY)) + "\n");
    writer.write("%%DocumentData: Clean7Bit\n");
    writer.write("%%DocumentProcessColors: Black\n");
    writer.write("%%ColorUsage: Color\n");
    writer.write("%%Origin: 0 0\n");
    writer.write("%%Pages: 1\n");
    writer.write("%%Page: 1 1\n");
    writer.write("%%EndComments\n\n");

    writer.write("gsave\n");

    if (_stringWriter != null)
    {
      writer.write(offsetX + " " + (offsetY) + " translate\n");

      _bufferedWriter.flush();
      StringBuffer buffer = _stringWriter.getBuffer();
      for (int i = 0; i < buffer.length(); i++)
      {
        writer.write(buffer.charAt(i));
      }

      writeFooter(writer);
    }
    else
    {
      writer.write(
              offsetX + " " + ((maxY - minY) - offsetY) + " translate\n");
    }

    writer.flush();
  }

  private void writeFooter(Writer writer) throws IOException
  {
    writer.write("grestore\n");
    if (isClipSet())
    {
      writer.write("grestore\n");
    }
    writer.write("showpage\n");
    writer.write("\n");
    writer.write("%%EOF");
    writer.flush();
  }

  public synchronized void flush() throws IOException
  {
    _bufferedWriter.flush();
  }

  public synchronized void close() throws IOException
  {
    if (_stringWriter == null)
    {
      writeFooter(_bufferedWriter);
      _bufferedWriter.flush();
      _bufferedWriter.close();
    }
  }

  public boolean isClipSet()
  {
    return _isClipSet;
  }

  public void setClipSet(boolean isClipSet)
  {
    _isClipSet = isClipSet;
  }

  private float minX;

  private float minY;

  private float maxX;

  private float maxY;

  private boolean _isClipSet = false;

  private String _title;

  private StringWriter _stringWriter;

  private BufferedWriter _bufferedWriter = null;

  // We need to remember which was the last EpsGraphics2D object to use
  // us, as we need to replace the clipping region if another EpsGraphics2D
  // object tries to use us.
  private EpsGraphics2D _lastG = null;

}
