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/*
 * Copyright 2013 serso aka se.solovyev
 *
 * 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.
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 * Contact details
 *
 * Email: [email protected]
 * Site:  http://se.solovyev.org
 */

package org.solovyev.android.keyboard;

import android.os.Handler;
import android.view.View;

import javax.annotation.Nonnull;
import javax.annotation.Nullable;

/**
 * User: serso
 * Date: 11/5/12
 * Time: 6:46 PM
 */
public class RepeatHelper {

	// in ms
	private static final int MAX_REPEAT_INTERVAL = 300;
	private static final int MIN_REPEAT_INTERVAL = 100;
	private static final int STEPS = 20;

	private static final int[] REPEAT_INTERVALS = new int[STEPS];

	static {
		for (int i = 0; i < REPEAT_INTERVALS.length; i++) {
			REPEAT_INTERVALS[i] = (STEPS - i) * (MAX_REPEAT_INTERVAL - MIN_REPEAT_INTERVAL) / (STEPS - 1);

		}
	}

	@Nullable
	private View repeatView;

	private int repeatInterval = REPEAT_INTERVALS[0];

	private long lastTime = 0;

	private int repeatCounter = 0;

	private boolean repeat = false;

	@Nonnull
	private final Handler uiHandler = new Handler();

	@Nullable
	private Runnable repeatRunnable;

	public synchronized void keyUp(@Nonnull View v) {
		if (this.repeatView == v) {
			clean(null);
		}
	}

	public synchronized void keyDown(@Nonnull View v, @Nullable final Runnable repeatRunnable) {
		clean(v);

		if (repeatRunnable != null) {
			this.repeatRunnable = new Runnable() {
				@Override
				public void run() {
					repeatRunnable.run();

					if (repeatCounter < REPEAT_INTERVALS.length) {
						repeatInterval = REPEAT_INTERVALS[repeatCounter];
					}
					repeatCounter++;

					uiHandler.postDelayed(this, repeatInterval);
				}
			};

			this.uiHandler.postDelayed(this.repeatRunnable, 1);
		}
	}

	private void clean(@Nullable View v) {
		this.repeatView = v;
		this.repeatCounter = 0;

		if (this.repeatRunnable != null) {
			this.uiHandler.removeCallbacks(this.repeatRunnable);
			this.repeatRunnable = null;
		}
	}
}