// Copyright 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

package org.chromium.chrome.browser.util;

import android.view.KeyEvent;

/**
 * This is a helper class to handle navigation related checks for key events.
 */
public class KeyNavigationUtil {

    /**
     * This is a helper class with no instance.
     */
    private KeyNavigationUtil() {
    }

    /**
     * Checks whether the given event is any of DPAD down or NUMPAD down.
     * @param event Event to be checked.
     * @return Whether the event should be processed as a navigation down.
     */
    public static boolean isGoDown(KeyEvent event) {
        return isActionDown(event) && (event.getKeyCode() == KeyEvent.KEYCODE_DPAD_DOWN
                || (!event.isNumLockOn() && event.getKeyCode() == KeyEvent.KEYCODE_NUMPAD_2));
    }

    /**
     * Checks whether the given event is any of DPAD up or NUMPAD up.
     * @param event Event to be checked.
     * @return Whether the event should be processed as a navigation up.
     */
    public static boolean isGoUp(KeyEvent event) {
        return isActionDown(event) && (event.getKeyCode() == KeyEvent.KEYCODE_DPAD_UP
                || (!event.isNumLockOn() && event.getKeyCode() == KeyEvent.KEYCODE_NUMPAD_8));
    }

    /**
     * Checks whether the given event is any of DPAD right or NUMPAD right.
     * @param event Event to be checked.
     * @return Whether the event should be processed as a navigation right.
     */
    public static boolean isGoRight(KeyEvent event) {
        return isActionDown(event) && (event.getKeyCode() == KeyEvent.KEYCODE_DPAD_RIGHT
                || (!event.isNumLockOn() && event.getKeyCode() == KeyEvent.KEYCODE_NUMPAD_6));
    }

    /**
     * Checks whether the given event is any of DPAD down, DPAD up, NUMPAD down or NUMPAD up.
     * @param event Event to be checked.
     * @return Whether the event should be processed as any of navigation up or navigation down.
     */
    public static boolean isGoUpOrDown(KeyEvent event) {
        return isGoDown(event) || isGoUp(event);
    }

    /**
     * Checks whether the given event is any of ENTER or NUMPAD ENTER.
     * @param event Event to be checked.
     * @return Whether the event should be processed as ENTER.
     */
    public static boolean isEnter(KeyEvent event) {
        return isActionUp(event) && (event.getKeyCode() == KeyEvent.KEYCODE_ENTER
                || event.getKeyCode() == KeyEvent.KEYCODE_NUMPAD_ENTER);
    }

    /**
     * Checks whether the given event is an ACTION_DOWN event.
     * @param event Event to be checked.
     * @return Whether the event is an ACTION_DOWN event.
     */
    public static boolean isActionDown(KeyEvent event) {
        return event.getAction() == KeyEvent.ACTION_DOWN;
    }

    /**
     * Checks whether the given event is an ACTION_UP event.
     * @param event Event to be checked.
     * @return Whether the event is an ACTION_UP event.
     */
    public static boolean isActionUp(KeyEvent event) {
        return event.getAction() == KeyEvent.ACTION_UP;
    }
}