package org.cass;

import java.io.*;
import java.util.*;

/** A utility class containing various functions for writing GRID files.
    @see Fits Fits
    @author Zachary Vaughan
    @version 1.1, 06/30/2006 */
public final class Grid
{
   /** The default minimum Z-axis value for GRID output. */
   public static final double ZMIN = 0;
   /** The default maximum Z-axis value for GRID output. */
   public static final double ZMAX = 1000;

   /** Writes the given image map to the given stream, assuming default axis
       ranges and binary output format.
      <p>This method assumes that system files are read and written in
         little-endian format.</p>
      @param out the given output stream.
      @param map the given image map.
      @throws IOException if there is an I/O error while writing.
      @throws NullPointerException if either <i>out</i> or <i>map</i> are
         <b>null</b>.
      @see #writeMap(OutputStream,float[][],double,double,double,double,double,double,boolean) writeMap(out,map,xmin,xmax,ymin,ymax,zmin,zmax,ascii) */
   public static void writeMap(OutputStream out, float[][] map)
   throws IOException
   {
      writeMap(out, map, 0, map.length, 0, map[0].length, ZMIN, ZMAX, false);
   }

   /** Writes the given image map to the given stream, assuming default axis
       ranges.
      <p>This method assumes that system files are read and written in
         little-endian format.</p>
      @param out the given output stream.
      @param map the given image map.
      @param ascii <b>true</b> for ASCII output format or <b>false</b> for
         binary output format.
      @throws IOException if there is an I/O error while writing.
      @throws NullPointerException if either <i>out</i> or <i>map</i> are
         <b>null</b>.
      @see #writeMap(OutputStream,float[][],double,double,double,double,double,double,boolean) writeMap(out,map,xmin,xmax,ymin,ymax,zmin,zmax,ascii) */
   public static void writeMap(OutputStream out, float[][] map, boolean ascii)
   throws IOException
   {
      writeMap(out, map, 0, map.length, 0, map[0].length, ZMIN, ZMAX, ascii);
   }

   /** Writes the given image map to the given stream using the given limits,
       assuming default X-axis and Y-axis ranges and binary output format.
      <p>This method assumes that system files are read and written in
         little-endian format.</p>
      @param out the given output stream.
      @param map the given image map.
      @param zmin the minimum Z-axis value.
      @param zmax the maximum Z-axis value.
      @throws IOException if there is an I/O error while writing.
      @throws NullPointerException if either <i>out</i> or <i>map</i> are
         <b>null</b>.
      @see #writeMap(OutputStream,float[][],double,double,double,double,double,double,boolean) writeMap(out,map,xmin,xmax,ymin,ymax,zmin,zmax,ascii) */
   public static void writeMap(OutputStream out, float[][] map,
                               double zmin, double zmax)
   throws IOException
   {
      writeMap(out, map, 0, map.length, 0, map[0].length, zmin, zmax, false);
   }

   /** Writes the given image map to the given stream using the given limits,
       assuming default X-axis and Y-axis ranges.
      <p>This method assumes that system files are read and written in
         little-endian format.</p>
      @param out the given output stream.
      @param map the given image map.
      @param zmin the minimum Z-axis value.
      @param zmax the maximum Z-axis value.
      @param ascii <b>true</b> for ASCII output format or <b>false</b> for
         binary output format.
      @throws IOException if there is an I/O error while writing.
      @throws NullPointerException if either <i>out</i> or <i>map</i> are
         <b>null</b>.
      @see #writeMap(OutputStream,float[][],double,double,double,double,double,double,boolean) writeMap(out,map,xmin,xmax,ymin,ymax,zmin,zmax,ascii) */
   public static void writeMap(OutputStream out, float[][] map,
                               double zmin, double zmax, boolean ascii)
   throws IOException
   {
      writeMap(out, map, 0, map.length, 0, map[0].length, zmin, zmax, ascii);
   }

   /** Writes the given image map to the given stream using the given limits,
       assuming the default Z-axis range and binary output format.
      <p>This method assumes that system files are read and written in
         little-endian format.</p>
      @param out the given output stream.
      @param map the given image map.
      @param xmin the minimum X-axis value.
      @param xmax the maximum X-axis value.
      @param ymin the minimum Y-axis value.
      @param ymax the maximum Y-axis value.
      @throws IOException if there is an I/O error while writing.
      @throws NullPointerException if either <i>out</i> or <i>map</i> are
         <b>null</b>.
      @see #writeMap(OutputStream,float[][],double,double,double,double,double,double,boolean) writeMap(out,map,xmin,xmax,ymin,ymax,zmin,zmax,ascii) */
   public static void writeMap(OutputStream out, float[][] map,
                               double xmin, double xmax,
                               double ymin, double ymax)
   throws IOException
   {
      writeMap(out, map, xmin, xmax, ymin, ymax, ZMIN, ZMAX, false);
   }

   /** Writes the given image map to the given stream using the given limits,
       assuming the default Z-axis range.
      <p>This method assumes that system files are read and written in
         little-endian format.</p>
      @param out the given output stream.
      @param map the given image map.
      @param xmin the minimum X-axis value.
      @param xmax the maximum X-axis value.
      @param ymin the minimum Y-axis value.
      @param ymax the maximum Y-axis value.
      @param ascii <b>true</b> for ASCII output format or <b>false</b> for
         binary output format.
      @throws IOException if there is an I/O error while writing.
      @throws NullPointerException if either <i>out</i> or <i>map</i> are
         <b>null</b>.
      @see #writeMap(OutputStream,float[][],double,double,double,double,double,double,boolean) writeMap(out,map,xmin,xmax,ymin,ymax,zmin,zmax,ascii) */
   public static void writeMap(OutputStream out, float[][] map,
                               double xmin, double xmax,
                               double ymin, double ymax, boolean ascii)
   throws IOException
   {
      writeMap(out, map, xmin, xmax, ymin, ymax, ZMIN, ZMAX, ascii);
   }

   /** Writes the given image map to the given stream using the given limits,
       assuming binary output format.
      <p>This method assumes that system files are read and written in
         little-endian format.</p>
      @param out the given output stream.
      @param map the given image map.
      @param xmin the minimum X-axis value.
      @param xmax the maximum X-axis value.
      @param ymin the minimum Y-axis value.
      @param ymax the maximum Y-axis value.
      @param zmin the minimum Z-axis value.
      @param zmax the maximum Z-axis value.
      @throws IOException if there is an I/O error while writing.
      @throws NullPointerException if either <i>out</i> or <i>map</i> are
         <b>null</b>.
      @see #writeMap(OutputStream,float[][],double,double,double,double,double,double,boolean) writeMap(out,map,xmin,xmax,ymin,ymax,zmin,zmax,ascii) */
   public static void writeMap(OutputStream out, float[][] map,
                               double xmin, double xmax,
                               double ymin, double ymax,
                               double zmin, double zmax)
   throws IOException
   {
      writeMap(out, map, xmin, xmax, ymin, ymax, zmin, zmax, false);
   }

   /** Writes the given image map to the given stream using the given limits.
      <p>This method assumes that system files are read and written in
         little-endian format.</p>
      @param out the given output stream.
      @param map the given image map.
      @param xmin the minimum X-axis value.
      @param xmax the maximum X-axis value.
      @param ymin the minimum Y-axis value.
      @param ymax the maximum Y-axis value.
      @param zmin the minimum Z-axis value.
      @param zmax the maximum Z-axis value.
      @param ascii <b>true</b> for ASCII output format or <b>false</b> for
         binary output format.
      @throws IOException if there is an I/O error while writing.
      @throws NullPointerException if either <i>out</i> or <i>map</i> are
         <b>null</b>. */
   public static void writeMap(OutputStream out, float[][] map,
                               double xmin, double xmax,
                               double ymin, double ymax,
                               double zmin, double zmax, boolean ascii)
   throws IOException
   {
      int width = map.length, height = map[0].length;
      int i = 0, x, y;

      if(ascii)
      {
         PrintWriter writer = new PrintWriter(new OutputStreamWriter(out));
         writer.println("DSAA");
         writer.println(xmin + " " + xmax);
         writer.println(ymin + " " + ymax);
         writer.print(zmin + " " + zmax);
         for(y = 0; y < height; y++) for(x = 0; x < width; x++)
            writer.print((i++ % 8 == 0 ? "\n" : "\t") + map[x][y]);
      }
      else
      {
         pWriteString(out, "DSBB");
         pWriteShort(out, width);
         pWriteShort(out, height);
         pWriteDouble(out, xmin);
         pWriteDouble(out, xmax);
         pWriteDouble(out, ymin);
         pWriteDouble(out, ymax);
         pWriteDouble(out, zmin);
         pWriteDouble(out, zmax);
         for(y = 0; y < height; y++) for(x = 0; x < width; x++)
            pWriteFloat(out, map[x][y]);
      }
      out.flush();
   }

   private static void pWriteString(OutputStream out, String s)
   throws IOException
   {
      for(int i = 0; i < s.length(); i++)
         out.write(s.charAt(i));
   }

   private static void pWriteShort(OutputStream out, int s) throws IOException
   {
      out.write(s);
      out.write(s >> 8);
   }

   private static void pWriteDouble(OutputStream out, double d)
   throws IOException
   {
      long b = Double.doubleToRawLongBits(d);
      int b1 = (int) (b >> 32), b2 = (int) b;
      out.write(b2);
      out.write(b2 >> 8);
      out.write(b2 >> 16);
      out.write(b2 >> 24);
      out.write(b1);
      out.write(b1 >> 8);
      out.write(b1 >> 16);
      out.write(b1 >> 24);
   }

   private static void pWriteFloat(OutputStream out, float f) throws IOException
   {
      int b = Float.floatToRawIntBits(f);
      out.write(b);
      out.write(b >> 8);
      out.write(b >> 16);
      out.write(b >> 24);
   }

   private Grid() {}
}