package org.daisy.pipeline.braille.dotify.calabash.impl;
   
   import javax.xml.namespace.QName;
   
   import org.daisy.dotify.api.table.BrailleConverter;
   import org.daisy.dotify.api.table.Table;
   import org.daisy.dotify.api.writer.MetaDataItem;
   import org.daisy.dotify.api.writer.PagedMediaWriter;
   import org.daisy.dotify.api.writer.Row;
  
  /**
   * PEF writer that converts braille from specified character set to Unicode braille.
   */
  class PEFWriter extends PEFMediaWriter implements PagedMediaWriter {
  
  	private static final QName DP2_ASCII = new QName("http://www.daisy.org/ns/pipeline/", "ascii", "dp2");
  
  	private final BrailleConverter brailleCharset;
  	private final Character space;
  
  	/**
  	 * @param brailleCharset Braille character set of provided rows objects.
  	 *                       <code>null</code> means the rows contain Unicode braille.
  	 */
  	PEFWriter(Table brailleCharset) {
  		super();
  		if (brailleCharset != null) {
  			this.brailleCharset = brailleCharset.newBrailleConverter();
  			this.space = this.brailleCharset.toText("\u2800").toCharArray()[0];
  			// trick to add namespace nodes to "pef" element
  			metadata.add(new MetaDataItem(new QName("http://www.w3.org/2000/xmlns/", DP2_ASCII.getPrefix(), "xmlns"),
  			                              DP2_ASCII.getNamespaceURI()));
  		} else {
  			this.brailleCharset = null;
  			this.space = '\u2800';
  		}
  	}
  
  	@Override
  	public void newRow(Row row) {
  		state.assertOpen();
  		pst.print("<row");
  		if (row.getRowSpacing() != null)
  			pst.print(" rowgap=\"" + (int) Math.floor((row.getRowSpacing() - 1) * 4) + "\"");
  		String chars = row.getChars();
  		if (chars.length() > 0) {
  			// HACK: because the Liblouis based translator always uses a space ('\s') to represent a
  			// blank dot pattern, no matter which braille character set was specified, we replace
  			// spaces with the correct representation here.
  			if (space != ' ')
  				chars = chars.replace(' ', space);
  			// also replace '\u2800' just to be sure
  			if (space != '\u2800')
  				chars = chars.replace('\u2800', space);
  			if (brailleCharset != null) {
  				pst.print(" " + DP2_ASCII.getPrefix() + ":" + DP2_ASCII.getLocalPart() + "=\"" + chars.replace("&", "&amp;")
  				                                                                                      .replace("\"", "&quot;")
  				                                                                                      .replace("<", "&lt;")
  				                                                                                      .replace(">", "&gt;")
  				                                                                                      + "\"");
  				try {
  					chars = brailleCharset.toBraille(chars);
  				} catch (RuntimeException e) {
  					throw new RuntimeException("Braille character set '" + brailleCharset + "' does not contain character", e);
  				}
  			}
  			pst.println(">" + chars + "</row>");
  		} else
  			pst.println("/>");
  	}
  }