/**********************************************
    * Copyright (C) 2010 Lukas Laag
    * This file is part of lib-gwt-svg-edu.
    * 
    * libgwtsvg-edu 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.
    * 
   * libgwtsvg-edu 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 libgwtsvg-edu.  If not, see http://www.gnu.org/licenses/
   **********************************************/
  package org.vectomatic.svg.edu.client.maze;
  
  import java.util.Collection;
  import java.util.HashMap;
  import java.util.Map;
  import java.util.Set;
  
  import com.google.gwt.user.client.Random;
  
  public abstract class Cell {
  	protected Map<Cell, Boundary> boundaries;
  	public Cell() {
  		boundaries = new HashMap<Cell, Boundary>();
  	}
  	public abstract String getId();
  	
  	public Collection<Boundary> getBoundaries() {
  		return boundaries.values();
  	}
  	public Set<Cell> getNeighbors() {
  		return boundaries.keySet();
  	}
  	public Boundary getBoundary(Cell neighbor) {
  		return boundaries.get(neighbor);
  	}
  	public boolean hasWall(Cell neighbor) {
  		return boundaries.get(neighbor).hasWall();
  	}
  	public void setHasWall(Cell neighbor, boolean hasWall) {
  		boundaries.get(neighbor).setHasWall(hasWall);
  	}
  	public boolean hasAllWalls() {
  		for (Boundary boundary : boundaries.values()) {
  			if (!boundary.hasWall()) {
  				return false;
  			}
  		}
  		return true;
  	}
  	public Cell getNeighborWithAllWalls() {
  		int count = 0;
      	for (Cell cell : getNeighbors()) {
      		if (cell.hasAllWalls()) {
      			count++;
      		}
      	}
      	if (count > 0) {
      		count = Random.nextInt(count);
          	for (Cell cell : getNeighbors()) {
          		if (cell.hasAllWalls()) {
          			if (count == 0) {
          				return cell;
          			} else {
                  		count--;
          			}
          		}
          	}
      	}
      	return null;
  	}
  	
  	@Override
  	public String toString() {
  		StringBuilder builder = new StringBuilder("[" + getId());
  		if (boundaries.size() > 0) {
  			builder.append(" : ");
  		}
  		for (Cell cell : boundaries.keySet()) {
  			builder.append(cell.getId());
  			builder.append(" ");
  		}
  		builder.append("]");
  		return builder.toString();
  	}
  }