package cse1030;

import java.util.SortedSet;
import java.util.TreeSet;

/**
 * A word puzzle where the letters 'a', 'e', 'i', 'o', and 'u' are missing from
 * the puzzle word and replaced with an underscore '_'. For example:
 * 
 * <p>
 * <code>MissingVowelsPuzzle p = new MissingVowelsPuzzle("facetious");<br />
 * System.out.println(p);
 * </code>
 * 
 * <p>
 * outputs:
 * 
 * <p>
 * <code>f_c_t___s : facetious</code>
 * 
 * <p>
 * A second example where the puzzle has multiple solutions:
 * 
 * <p>
 * <code>MissingVowelsPuzzle p = new MissingVowelsPuzzle("cat", "cot", "cut");<br />
 * System.out.println(p);
 * </code>
 * 
 * <p>
 * outputs:
 * 
 * <p>
 * <code>c_t : cat, cot, cut</code>
 * 
 * 
 * 
 * @author EECS1030_2014_15W
 * 
 */
public class MissingVowelsPuzzle extends AbstractWordPuzzle {

  private SortedSet<String> solutions;

  /**
   * Constructs a missing vowels word puzzle for the solution word
   * <code>solution</code>. The puzzle word is the solution word with the
   * letters 'a', 'e', 'i', 'o', and 'u' replaced with an underscore '_'.
   * 
   * @param solution
   *          a solution word
   */
  public MissingVowelsPuzzle(String solution) {
    super();
    this.setPuzzleWord(MissingVowelsPuzzle.computePuzzleWord(solution));
    this.solutions = new TreeSet<String>();
    this.solutions.add(solution);
  }

  /**
   * Constructs a missing vowels word puzzle for the solution word
   * <code>solution</code>. All other possible solutions should also be
   * provided.
   * 
   * @param solution
   *          a solution word
   * @param otherSolutions
   *          all other solutions to the puzzle
   * @throws IllegalArgumentException
   *           if a solution in <code>otherSolutions</code> is incompatible with
   *           <code>solution</code>.
   */
  public MissingVowelsPuzzle(String solution, String... otherSolutions) {
    this(solution);
    for (String s : otherSolutions) {
      if (this.getSolution().equals(MissingVowelsPuzzle.computePuzzleWord(s))) {
        this.solutions.add(s);
      } else {
        throw new IllegalArgumentException(s + " is not a solution for "
            + this.getPuzzleWord());
      }
    }
  }


  /**
   * Get the solution word. If there is more than one solution this method
   * returns the solution that comes first in dictionary order.
   * 
   * @return the solution word that comes first in dictionary order
   */
  @Override
  public String getSolution() {
    return this.solutions.first();
  }

  /**
   * Get a sorted set of all of the solution words.
   * 
   * <p>
   * The set returned by this method cannot be used to modify the solutions for
   * this puzzle.
   * 
   * @return a sorted set of solution words
   */
  @Override
  public SortedSet<String> getSolutions() {
    return new TreeSet<String>(this.solutions);
  }

  

  /**
   * Compute the puzzle word corresponding to a <code>solution</code> word. The
   * puzzle word is the solution word with the letters 'a', 'e', 'i', 'o', and
   * 'u' replaced with an underscore '_'.
   * 
   * @param solution
   *          a solution word
   * @return the puzzle word
   */
  private static String computePuzzleWord(String solution) {
    return solution.replaceAll("[aeiou]", "_");
  }
}