/*
    * #%L
    * prolobjectlink-jpi
    * %%
    * Copyright (C) 2019 Prolobjectlink Project
    * %%
    * Permission is hereby granted, free of charge, to any person obtaining a copy
    * of this software and associated documentation files (the "Software"), to deal
    * in the Software without restriction, including without limitation the rights
   * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   * copies of the Software, and to permit persons to whom the Software is
   * furnished to do so, subject to the following conditions:
   * 
   * The above copyright notice and this permission notice shall be included in
   * all copies or substantial portions of the Software.
   * 
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
   * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
   * THE SOFTWARE.
   * #L%
   */
  package io.github.prolobjectlink.prolog;
  
  import java.util.Arrays;
  import java.util.Collection;
  import java.util.Iterator;
  import java.util.List;
  import java.util.Map;
  
  /**
   * Partial implementation of {@link PrologQuery} interface.
   * 
   * @author Jose Zalacain
   * @since 1.0
   */
  public abstract class AbstractQuery extends AbstractIterator<Collection<PrologTerm>> implements PrologQuery {
  
  	// engine for execute queries
  	protected final AbstractEngine engine;
  
  	public AbstractQuery(AbstractEngine engine) {
  		this.engine = engine;
  	}
  
  	public final PrologEngine getEngine() {
  		return engine;
  	}
  
  	public final PrologProvider getProvider() {
  		return engine.getProvider();
  	}
  
  	protected final <K extends PrologTerm> K toTerm(Object o, Class<K> from) {
  		return engine.toTerm(o, from);
  	}
  
  	protected final <K extends PrologTerm, V extends Object> Map<String, PrologTerm>[] toTermMapArray(
  			Map<String, V>[] map, Class<K> from) {
  		return engine.toTermMapArray(map, from);
  	}
  
  	protected final <K> K fromTerm(PrologTerm term, Class<K> to) {
  		return engine.fromTerm(term, to);
  	}
  
  	protected final boolean contains(List<Map<String, PrologTerm>> maps, Map<String, PrologTerm> map) {
  		for (Map<String, PrologTerm> m : maps) {
  			if (m.equals(map)) {
  				return true;
  			}
  		}
  		return false;
  	}
  
  	protected final boolean contains(List<PrologTerm[]> arrays, PrologTerm[] array) {
  		for (PrologTerm[] a : arrays) {
  			if (Arrays.equals(a, array)) {
  				return true;
  			}
  		}
  		return false;
  	}
  
  	protected final PrologLogger getLogger() {
  		return getProvider().getLogger();
  	}
  
  	public final Iterator<Collection<PrologTerm>> iterator() {
  		return new PrologQueryIterator(this);
  	}
  
  	public final boolean hasNext() {
  		return hasMoreSolutions();
  	}
  
 	public final Collection<PrologTerm> next() {
 		// don't check has next
 		// don't raise NoSuchElementException
 		return nextVariablesSolution().values();
 	}
 
 	@Override
 	public final void remove() {
 		// skip invoking next
 		nextSolution();
 	}
 
 	public final Map<String, PrologTerm> one() {
 		return oneVariablesSolution();
 	}
 
 	public final List<Map<String, PrologTerm>> nths(int n) {
 		Map<String, PrologTerm>[] maps = nVariablesSolutions(n);
 		return Arrays.asList(maps);
 	}
 
 	public final Map<String, PrologTerm> more() {
 		return nextVariablesSolution();
 	}
 
 	public final List<Object> oneResult() {
 		PrologTerm[] terms = oneSolution();
 		return getProvider().getJavaConverter().toObjectList(terms);
 	}
 
 	public final List<Object> nextResult() {
 		PrologTerm[] terms = nextSolution();
 		return getProvider().getJavaConverter().toObjectList(terms);
 	}
 
 	public final List<List<Object>> nResult(int n) {
 		PrologTerm[][] terms = allSolutions();
 		return getProvider().getJavaConverter().toObjectLists(terms);
 	}
 
 	public final List<List<Object>> allResults() {
 		PrologTerm[][] terms = allSolutions();
 		return getProvider().getJavaConverter().toObjectLists(terms);
 	}
 
 	public final Map<String, Object> oneVariablesResult() {
 		Map<String, PrologTerm> map = oneVariablesSolution();
 		return getProvider().getJavaConverter().toObjectMap(map);
 	}
 
 	@Override
 	public final Map<String, Object> nextVariablesResult() {
 		Map<String, PrologTerm> map = nextVariablesSolution();
 		return getProvider().getJavaConverter().toObjectMap(map);
 	}
 
 	@Override
 	public final List<Map<String, Object>> nVariablesResults(int n) {
 		Map<String, PrologTerm>[] maps = nVariablesSolutions(n);
 		return getProvider().getJavaConverter().toObjectMaps(maps);
 	}
 
 	public final List<Map<String, Object>> allVariablesResults() {
 		Map<String, PrologTerm>[] maps = allVariablesSolutions();
 		return getProvider().getJavaConverter().toObjectMaps(maps);
 	}
 
 	@Override
 	public int hashCode() {
 		final int prime = 31;
 		int result = 1;
 		result = prime * result + ((engine == null) ? 0 : engine.hashCode());
 		return result;
 	}
 
 	@Override
 	public boolean equals(Object obj) {
 		if (this == obj)
 			return true;
 		if (obj == null)
 			return false;
 		if (getClass() != obj.getClass())
 			return false;
 		AbstractQuery other = (AbstractQuery) obj;
 		if (engine == null) {
 			if (other.engine != null)
 				return false;
 		} else if (!engine.equals(other.engine)) {
 			return false;
 		}
 		return true;
 	}
 
 }