content: /**
   * Copyright (c) 2019-2020, the Alpha Team.
   * All rights reserved.
   * 
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions are met:
   * 
   * 1) Redistributions of source code must retain the above copyright notice, this
   *    list of conditions and the following disclaimer.
   * 
   * 2) Redistributions in binary form must reproduce the above copyright notice,
   *    this list of conditions and the following disclaimer in the documentation
   *    and/or other materials provided with the distribution.
   * 
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
   * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
   * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
   * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
   * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
   * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
   * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  package at.ac.tuwien.kr.alpha.app;
  
  
  import at.ac.tuwien.kr.alpha.api.programs.analysis.DependencyGraph;
  
  import java.io.OutputStream;
  import java.io.PrintStream;
  import java.util.HashMap;
  import java.util.List;
  import java.util.Map;
  import java.util.Set;
  import java.util.function.BiFunction;
  
  public class DependencyGraphWriter {
  
  	private static final String DEFAULT_GRAPH_HEADING = "digraph dependencyGraph";
  
  	private static final String DEFAULT_NODE_FORMAT = "n%d [label = \"%s\"]%n";
  	private static final String DEFAULT_EDGE_FORMAT = "n%d -> n%d [xlabel=\"%s\" labeldistance=0.1]%n";
  
  	public void writeAsDot(DependencyGraph graph, OutputStream out) {
  		writeAsDot(graph.getAdjancencyMap(), out);
  	}
  
  	private void writeAsDot(Map<DependencyGraph.Node, List<DependencyGraph.Edge>> graph, OutputStream out) {
  		BiFunction<DependencyGraph.Node, Integer, String> nodeFormatter = this::buildNodeString;
  		writeAsDot(graph, out, nodeFormatter);
  	}
  
  	private void writeAsDot(Map<DependencyGraph.Node, List<DependencyGraph.Edge>> graph, OutputStream out, BiFunction<DependencyGraph.Node, Integer, String> nodeFormatter) {
  		PrintStream ps = new PrintStream(out);
  		startGraph(ps);
  
  		Set<Map.Entry<DependencyGraph.Node, List<DependencyGraph.Edge>>> graphDataEntries = graph.entrySet();
  		// First, write all nodes.
  		int nodeCnt = 0;
  		Map<DependencyGraph.Node, Integer> nodesToNumbers = new HashMap<>();
  		for (Map.Entry<DependencyGraph.Node, List<DependencyGraph.Edge>> entry : graphDataEntries) {
  			ps.print(nodeFormatter.apply(entry.getKey(), nodeCnt));
  			nodesToNumbers.put(entry.getKey(), nodeCnt);
  			nodeCnt++;
  		}
  
  		// Second, write all edges.
  		for (Map.Entry<DependencyGraph.Node, List<DependencyGraph.Edge>> entry : graphDataEntries) {
  			int fromNodeNum = nodesToNumbers.get(entry.getKey());
  			for (DependencyGraph.Edge edge : entry.getValue()) {
  				int toNodeNum = nodesToNumbers.get(edge.getTarget());
  				ps.printf(DependencyGraphWriter.DEFAULT_EDGE_FORMAT, fromNodeNum, toNodeNum, edge.getSign() ? "+" : "-");
  			}
  		}
  
  		finishGraph(ps);
  		ps.close();
  	}
  
  	private void startGraph(PrintStream ps) {
  		ps.println(DependencyGraphWriter.DEFAULT_GRAPH_HEADING);
  		ps.println("{");
  		ps.println("splines=false;");
  		ps.println("ranksep=4.0;");
  	}
  
  	private void finishGraph(PrintStream ps) {
  		ps.println("}");
  	}
  
  	private String buildNodeString(DependencyGraph.Node n, int nodeNum) {
  		return String.format(DependencyGraphWriter.DEFAULT_NODE_FORMAT, nodeNum, n.getLabel());
  	}
  
  }
  