/*
 * The JTS Topology Suite is a collection of Java classes that
 * implement the fundamental operations required to validate a given
 * geo-spatial data set to a known topological specification.
 *
 * Copyright (C) 2001 Vivid Solutions
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * For more information, contact:
 *
 *     Vivid Solutions
 *     Suite #1A
 *     2328 Government Street
 *     Victoria BC  V8T 5G5
 *     Canada
 *
 *     (250)385-6040
 *     www.vividsolutions.com
 */
package com.revolsys.geometry.geomgraph;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.TreeMap;

import com.revolsys.geometry.noding.OrientedCoordinateArray;

/**
 * A EdgeList is a list of Edges.  It supports locating edges
 * that are pointwise equals to a target edge.
 * @version 1.7
 */
public class EdgeList implements Iterable<Edge> {
  private final List<Edge> edges = new ArrayList<>();

  /**
   * An index of the edges, for fast lookup.
   *
   */
  private final Map<OrientedCoordinateArray, Edge> ocaMap = new TreeMap<>();

  public EdgeList() {
  }

  /**
   * Insert an edge unless it is already in the list
   */
  public void add(final Edge edge) {
    this.edges.add(edge);
    final OrientedCoordinateArray oca = new OrientedCoordinateArray(edge.getLine());
    this.ocaMap.put(oca, edge);
  }

  public void addAll(final Collection<? extends Edge> edges) {
    for (final Edge edge : edges) {
      add(edge);
    }
  }

  /**
   * If the edge e is already in the list, return its index.
   * @return  index, if e is already in the list
   *          -1 otherwise
   */
  public int findEdgeIndex(final Edge e) {
    int i = 0;
    for (final Edge edge : this.edges) {
      if (edge.equals(e)) {
        return i;
      }
      i++;
    }
    return -1;
  }

  /**
   * If there is an edge equal to e already in the list, return it.
   * Otherwise return null.
   * @return  equal edge, if there is one already in the list
   *          null otherwise
   */
  public Edge findEqualEdge(final Edge e) {
    final OrientedCoordinateArray oca = new OrientedCoordinateArray(e.getLine());
    // will return null if no edge matches
    final Edge matchEdge = this.ocaMap.get(oca);
    return matchEdge;
  }

  public Edge get(final int i) {
    return this.edges.get(i);
  }

  public List<Edge> getEdges() {
    return this.edges;
  }

  @Override
  public Iterator<Edge> iterator() {
    return this.edges.iterator();
  }

  @Override
  public String toString() {
    return this.edges.toString();
  }

}