content: /**
   *  Copyright (c) 2013-2016 Angelo ZERR.
   *  All rights reserved. This program and the accompanying materials
   *  are made available under the terms of the Eclipse Public License v1.0
   *  which accompanies this distribution, and is available at
   *  http://www.eclipse.org/legal/epl-v10.html
   *
   *  Contributors:
   *  Angelo Zerr <angelo.zerr@gmail.com> - initial API and implementation
   */
  package tern.eclipse.ide.tools.internal.ui.console;
  
  import tern.eclipse.ide.ui.console.LineType;
  
  /**
   * Tern repository console document.
   *
   */
  public class ConsoleDocument {
  
  	private LineType[] lineTypes;
  
  	private String[] lines;
  
  	private int writeIndex = 0;
  
  	private int readIndex = 0;
  
  	private static final int BUFFER_SIZE = 200;
  
  	protected static class ConsoleLine {
  		private String line;
  
  		private LineType type;
  
  		ConsoleLine(String line, LineType type) {
  			this.line = line;
  			this.type = type;
  		}
  
  		public String getLine() {
  			return line;
  		}
  
  		public LineType getType() {
  			return type;
  		}
  	}
  
  	/**
  	 * Creates an empty console document.
  	 */
  	public ConsoleDocument() {
  		// nothing to initialize
  	}
  
  	/**
  	 * Clears the console document.
  	 */
  	public void clear() {
  		lineTypes = null;
  		lines = null;
  		writeIndex = 0;
  		readIndex = 0;
  	}
  
  	/**
  	 * Appends a line of the specified type to the end of the console.
  	 */
  	public void appendConsoleLine(LineType lineType, String line) {
  		if (lines == null) {
  			lines = new String[BUFFER_SIZE];
  			lineTypes = new LineType[BUFFER_SIZE];
  		}
  		lines[writeIndex] = line; //$NON-NLS-1$
  		lineTypes[writeIndex] = lineType;
  
  		if (++writeIndex >= BUFFER_SIZE) {
  			writeIndex = 0;
  		}
  		if (writeIndex == readIndex) {
  			if (++readIndex >= BUFFER_SIZE) {
  				readIndex = 0;
  			}
  		}
  	}
  
  	public ConsoleLine[] getLines() {
  		if (isEmpty()) {
  			return new ConsoleLine[0];
  		}
  		ConsoleLine[] docLines = new ConsoleLine[readIndex > writeIndex ? BUFFER_SIZE
  				: writeIndex];
  		int index = readIndex;
  		for (int i = 0; i < docLines.length; i++) {
  			docLines[i] = new ConsoleLine(lines[index], lineTypes[index]);
  			if (++index >= BUFFER_SIZE) {
  				index = 0;
  			}
  		}
  		return docLines;
  	}
  
  	public boolean isEmpty() {
  		return writeIndex == readIndex;
  	}
  }
  