package eu.simuline.octave.io.impl;
   
   import eu.simuline.octave.io.spi.OctaveDataWriter;
   import eu.simuline.octave.type.matrix.AbstractGenericMatrix;
   
   import java.io.IOException;
   import java.io.Writer;
   
  /**
   * Common Writer class for primitive java types: Boolean, Double, Integer.... 
   *
   * @param <T>
   *    the type to be written out 
   *    which has to extend {@link AbstractGenericMatrix}. 
   */
  abstract class AbstractPrimitiveMatrixWriter
      <T extends AbstractGenericMatrix<?,?>> 
      extends OctaveDataWriter<T> {
  
      protected static final String NDIMS    = "# ndims: ";
      protected static final String NROWS    = "# rows: ";
      protected static final String NCOLUMNS = "# columns: ";
  
      // prevents instantiation (as does keyword abstract); for pmd only 
      protected AbstractPrimitiveMatrixWriter() {
      }
  
      // **** indicates that it would be a good idea 
      // to merge reader and writer 
      // and to have one OctaveObject for each octave type. 
      protected abstract String octaveMatrixType();
  
      // **** indicates that it would be a good idea 
      // to merge reader and writer 
      // and to have one OctaveObject for each octave type. 
      protected abstract String octaveScalarType();
  
      // is used for integer types only, for logical and floating point, 
      // it is overwritten 
      public void write(final Writer writer, 
  		      final T octaveMatrix) throws IOException {
  	if (octaveMatrix.getSizeLength() == 2 && 
  	    octaveMatrix.getSize(1) == 1 && 
  	    octaveMatrix.getSize(2) == 1) {
  
  	    writer.write("# type: " + octaveScalarType() + "\n");
  	    writer.write(octaveMatrix.getPlainString(0) + "\n");
  	} else {
  	    writer.write("# type: " + octaveMatrixType() + "\n");
  	    // **** note: unlike for floating types and bool, 
  	    // for integer types, 
  	    // there is no special case for 2 dimensions, i.e. matrices 
  	    // using saveData2d(writer, octaveMatrix);
  	    saveDataVectorized(writer, octaveMatrix);
  	}
      }
  
      protected void saveDataVectorized(final Writer writer, 
  				      final T octaveMatrix) 
  	throws IOException {
  
          writer.write(NDIMS + octaveMatrix.getSizeLength() + "\n");
          for (int idx = 1; idx <= octaveMatrix.getSizeLength(); idx++) {
              writer.write(" " + octaveMatrix.getSize(idx));
          }
  
  	int len = octaveMatrix.dataSize();
          for (int idx = 0; idx < len; idx++) {
              writer.write("\n " + octaveMatrix.getPlainString(idx));
  	}
  
          writer.write("\n");
      }
  
  }