content: /*************************************************************************
  *                                                                        *
  *  This file is part of the 20n/act project.                             *
  *  20n/act enables DNA prediction for synthetic biology/bioengineering.  *
  *  Copyright (C) 2017 20n Labs, Inc.                                     *
  *                                                                        *
  *  Please direct all queries to act@20n.com.                             *
  *                                                                        *
  *  This program 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.                                   *
  *                                                                        *
  *  This program 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 this program.  If not, see <http://www.gnu.org/licenses/>. *
  *                                                                        *
  *************************************************************************/
  
  package com.act.biointerpretation.networkanalysis.GraphViz;
  
  /**
   * An edge in a GraphViz graph.
   * The edge knows about its source node, sink node, color, and style, and can write out the appropriate DOT language
   * string to add itself to a graph.
   */
  public class DotEdge {
  
    private static final String EDGE_SYMBOL = "->";
    private static final String END_LINE = ";\n";
  
    private final String source;
    private final String sink;
    private DotColor color;
    private EdgeStyle style;
  
    public DotEdge(String source, String sink) {
      this(source, sink, DotColor.DEFAULT_BLACK, EdgeStyle.DEFAULT_SOLID);
    }
  
    public DotEdge(String source, String sink, DotColor color, EdgeStyle style) {
      this.source = source;
      this.sink = sink;
      this.color = color;
      this.style = style;
    }
  
    /**
     * Gets the string that should be written to a DOT file to add this edge to a graph.
     * See user manual for dot format here: http://graphviz.org/Documentation/dotguide.pdf
     * @return The string.
     */
    public String getDotString() {
      return new StringBuilder()
          .append(source)
          .append(EDGE_SYMBOL)
          .append(sink)
          .append(color.getColorString())
          .append(style.stringRep)
          .append(END_LINE).toString();
    }
  
    /**
     * @return The DotEdge to allow chaining.
     */
    public DotEdge setColor(DotColor color) {
      this.color = color;
      return this;
    }
  
    /**
     * @return The DotEdge to allow chaining.
     */
    public DotEdge setStyle(EdgeStyle style) {
      this.style = style;
      return this;
    }
  
    /**
     * Possible styles of an edge.
     */
    public enum EdgeStyle {
      DEFAULT_SOLID(),
      DOTTED("dotted");
  
      private String stringRep;
  
      EdgeStyle() {
        this.stringRep = "";
      }
  
      EdgeStyle(String style) {
        this.stringRep = "[style=" + style + "]";
      }
    }
  }
  