/*
 * Copyright (C) 2015 Andrey Kulikov (andkulikov@gmail.com)
 *
 * 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.
 */
package com.transitionseverywhere.utils;

import android.animation.ValueAnimator;
import android.annotation.TargetApi;
import android.graphics.PointF;
import android.os.Build;
import android.support.annotation.NonNull;

import java.lang.ref.WeakReference;

/**
 * Created by Andrey Kulikov on 17.08.15.
 */
@TargetApi(Build.VERSION_CODES.ICE_CREAM_SANDWICH)
public abstract class BasePointFAnimator extends ValueAnimator implements ValueAnimator.AnimatorUpdateListener {

    /**
     * A weak reference to the mTarget object on which the property exists, set
     * in the constructor. We'll cancel the animation if this goes away.
     */
    @NonNull
    private final WeakReference mTarget;

    @NonNull
    private final PointFProperty mPointFProperty;

    @NonNull
    private final PointF mTempPointF = new PointF();

    protected BasePointFAnimator(@NonNull Object target, @NonNull PointFProperty pointFProperty) {
        mTarget = new WeakReference<>(target);
        mPointFProperty = pointFProperty;
        setFloatValues(0f, 1f);
        addUpdateListener(this);
    }

    protected abstract void applyAnimatedFraction(@NonNull PointF holder, float fraction);

    @Override
    public void onAnimationUpdate(@NonNull ValueAnimator animation) {
        Object target = mTarget.get();
        if (target == null) {
            // We lost the target reference, cancel.
            cancel();
            return;
        }
        applyAnimatedFraction(mTempPointF, animation.getAnimatedFraction());
        mPointFProperty.set(target, mTempPointF);
    }
}