package com.androidmess.becultural.common;/*
 * Copyright 2015 The Android Open Source Project
 *
 * 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.
 */

import android.content.Context;
import android.os.Build;
import android.support.design.widget.CoordinatorLayout;
import android.support.design.widget.FloatingActionButton;
import android.support.v4.view.ViewCompat;
import android.support.v4.view.ViewPropertyAnimatorListener;
import android.support.v4.view.animation.FastOutSlowInInterpolator;
import android.util.AttributeSet;
import android.view.View;
import android.view.animation.Animation;
import android.view.animation.AnimationUtils;
import android.view.animation.Interpolator;

import com.androidmess.becultural.R;

public class ScrollFabBehaviour extends FloatingActionButton.Behavior {
  private static final Interpolator INTERPOLATOR = new FastOutSlowInInterpolator();
  private boolean mIsAnimatingOut = false;

  public ScrollFabBehaviour(Context context, AttributeSet attrs) {
    super();
  }

  @Override
  public boolean onStartNestedScroll(final CoordinatorLayout coordinatorLayout, final FloatingActionButton child,
                                     final View directTargetChild, final View target, final int nestedScrollAxes) {
    // Ensure we react to vertical scrolling
    return nestedScrollAxes == ViewCompat.SCROLL_AXIS_VERTICAL
            || super.onStartNestedScroll(coordinatorLayout, child, directTargetChild, target, nestedScrollAxes);
  }

  @Override
  public void onNestedScroll(final CoordinatorLayout coordinatorLayout, final FloatingActionButton child,
                             final View target, final int dxConsumed, final int dyConsumed,
                             final int dxUnconsumed, final int dyUnconsumed) {
    super.onNestedScroll(coordinatorLayout, child, target, dxConsumed, dyConsumed, dxUnconsumed, dyUnconsumed);
    if (dyConsumed > 0 && !this.mIsAnimatingOut && child.getVisibility() == View.VISIBLE) {
      // User scrolled down and the FAB is currently visible -> hide the FAB
      animateOut(child);
    } else if (dyConsumed < 0 && child.getVisibility() != View.VISIBLE) {
      // User scrolled up and the FAB is currently not visible -> show the FAB
      animateIn(child);
    }
  }

  // Same animation that FloatingActionButton.Behavior uses to hide the FAB when the AppBarLayout exits
  private void animateOut(final FloatingActionButton button) {
    if (Build.VERSION.SDK_INT >= 14) {
      ViewCompat.animate(button).scaleX(0.0F).scaleY(0.0F).alpha(0.0F).setInterpolator(INTERPOLATOR).withLayer()
              .setListener(new ViewPropertyAnimatorListener() {
                public void onAnimationStart(View view) {
                  ScrollFabBehaviour.this.mIsAnimatingOut = true;
                }

                public void onAnimationCancel(View view) {
                  ScrollFabBehaviour.this.mIsAnimatingOut = false;
                }

                public void onAnimationEnd(View view) {
                  ScrollFabBehaviour.this.mIsAnimatingOut = false;
                  view.setVisibility(View.GONE);
                }
              }).start();
    } else {
      Animation anim = AnimationUtils.loadAnimation(button.getContext(), R.anim.fab_out);
      anim.setInterpolator(INTERPOLATOR);
      anim.setDuration(200L);
      anim.setAnimationListener(new Animation.AnimationListener() {
        public void onAnimationStart(Animation animation) {
          ScrollFabBehaviour.this.mIsAnimatingOut = true;
        }

        public void onAnimationEnd(Animation animation) {
          ScrollFabBehaviour.this.mIsAnimatingOut = false;
          button.setVisibility(View.GONE);
        }

        @Override
        public void onAnimationRepeat(final Animation animation) {
        }
      });
      button.startAnimation(anim);
    }
  }

  // Same animation that FloatingActionButton.Behavior uses to show the FAB when the AppBarLayout enters
  private void animateIn(FloatingActionButton button) {
    button.setVisibility(View.VISIBLE);
    if (Build.VERSION.SDK_INT >= 14) {
      ViewCompat.animate(button).scaleX(1.0F).scaleY(1.0F).alpha(1.0F)
              .setInterpolator(INTERPOLATOR).withLayer().setListener(null)
              .start();
    } else {
      Animation anim = AnimationUtils.loadAnimation(button.getContext(), R.anim.fab_in);
      anim.setDuration(200L);
      anim.setInterpolator(INTERPOLATOR);
      button.startAnimation(anim);
    }
  }
}