/**
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on
 * an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
 * specific language governing permissions and limitations under the License.
 *
 * Copyright 2012-2015 the original author or authors.
 */
package org.assertj.swing.jide.grids.driver;

import java.awt.Component;
import java.awt.Container;
import java.util.ArrayList;
import java.util.List;

import javax.swing.JList;

import org.assertj.swing.annotation.RunsInEDT;
import org.assertj.swing.core.ComponentMatcher;
import org.assertj.swing.core.Robot;
import org.assertj.swing.core.TypeMatcher;

/**
 * Understands look up of the <code>{@link javax.swing.JList}</code> in the pop-up raised by a
 * <code>{@link com.jidesoft.combobox.AbstractComboBox}</code>, if the implementation actually uses one.
 */
class AbstractComboBoxDropDownListFinder {

  private static final ComponentMatcher LIST_MATCHER = new TypeMatcher(JList.class);

  private final Robot _robot;

  AbstractComboBoxDropDownListFinder(Robot robot) {
	_robot = robot;
  }

  /**
   * Finds the <code>{@link javax.swing.JList}</code> in the pop-up raised by a
   * <code>{@link com.jidesoft.combobox.AbstractComboBox}</code>, if the implementation actually uses one.
   * <p>
   * <b>Note:</b> this method is <b>not</b> executed in the event dispatch thread. Callers are responsible for calling
   * this method in the event dispatch thread.
   * 
   * @return the found <code>JList</code>, or <code>null</code> if a drop-down list cannot be found.
   */
  @RunsInEDT
  JList findDropDownList(Container startFrom) {
	return findListIn(startFrom);
  }

  private JList findListIn(Container parent) {
	List<Component> found = new ArrayList<Component>(_robot.finder().findAll(parent, LIST_MATCHER));
	if (found.size() != 1) {
	  return null;
	}
	final Component c = found.get(0);
	if (c instanceof JList) {
	  return (JList) c;
	}
	return null;
  }
}