package jalview.util.matcher;

import java.util.ArrayList;
import java.util.List;
import java.util.function.Function;

public class KeyedMatcherSet implements KeyedMatcherSetI
{
  List<KeyedMatcherI> matchConditions;

  boolean andConditions;

  /**
   * Constructor
   */
  public KeyedMatcherSet()
  {
    matchConditions = new ArrayList<>();
  }

  @Override
  public boolean matches(Function<String[], String> valueProvider)
  {
    /*
     * no conditions matches anything
     */
    if (matchConditions.isEmpty())
    {
      return true;
    }

    /*
     * AND until failure
     */
    if (andConditions)
    {
      for (KeyedMatcherI m : matchConditions)
      {
        if (!m.matches(valueProvider))
        {
          return false;
        }
      }
      return true;
    }

    /*
     * OR until match
     */
    for (KeyedMatcherI m : matchConditions)
    {
      if (m.matches(valueProvider))
      {
        return true;
      }
    }
    return false;
  }

  @Override
  public KeyedMatcherSetI and(KeyedMatcherI m)
  {
    if (!andConditions && matchConditions.size() > 1)
    {
      throw new IllegalStateException("Can't add an AND to OR conditions");
    }
    matchConditions.add(m);
    andConditions = true;

    return this;
  }

  @Override
  public KeyedMatcherSetI or(KeyedMatcherI m)
  {
    if (andConditions && matchConditions.size() > 1)
    {
      throw new IllegalStateException("Can't add an OR to AND conditions");
    }
    matchConditions.add(m);
    andConditions = false;

    return this;
  }

  @Override
  public boolean isAnded()
  {
    return andConditions;
  }

  @Override
  public Iterable<KeyedMatcherI> getMatchers()
  {
    return matchConditions;
  }

  @Override
  public String toString()
  {
    StringBuilder sb = new StringBuilder();
    boolean first = true;
    for (KeyedMatcherI matcher : matchConditions)
    {
      if (!first)
      {
        sb.append(andConditions ? " AND " : " OR ");
      }
      first = false;
      sb.append("(").append(matcher.toString()).append(")");
    }
    return sb.toString();
  }

  @Override
  public boolean isEmpty()
  {
    return matchConditions == null || matchConditions.isEmpty();
  }

}