/*
 * Copyright (C) 2017 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.
 */

package org.fdroid.fdroid.views;

import android.content.Context;
import android.util.AttributeSet;
import android.view.View;

import com.google.android.material.appbar.AppBarLayout;

import androidx.coordinatorlayout.widget.CoordinatorLayout;
import androidx.core.view.ViewCompat;

/**
 * Workaround AppBarLayout.Behavior for https://issuetracker.google.com/66996774
 * Source: https://gist.github.com/chrisbanes/8391b5adb9ee42180893300850ed02f2
 */
public class FixAppBarLayoutBehavior extends AppBarLayout.Behavior {

    public FixAppBarLayoutBehavior() {
        super();
    }

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

    @Override
    public void onNestedScroll(CoordinatorLayout coordinatorLayout, AppBarLayout child, View target,
                               int dxConsumed, int dyConsumed, int dxUnconsumed, int dyUnconsumed, int type) {
        super.onNestedScroll(coordinatorLayout, child, target, dxConsumed, dyConsumed,
                dxUnconsumed, dyUnconsumed, type);
        stopNestedScrollIfNeeded(dyUnconsumed, child, target, type);
    }

    @Override
    public void onNestedPreScroll(CoordinatorLayout coordinatorLayout, AppBarLayout child,
                                  View target, int dx, int dy, int[] consumed, int type) {
        super.onNestedPreScroll(coordinatorLayout, child, target, dx, dy, consumed, type);
        stopNestedScrollIfNeeded(dy, child, target, type);
    }

    private void stopNestedScrollIfNeeded(int dy, AppBarLayout child, View target, int type) {
        if (type == ViewCompat.TYPE_NON_TOUCH) {
            final int currOffset = getTopAndBottomOffset();
            if ((dy < 0 && currOffset == 0)
                    || (dy > 0 && currOffset == -child.getTotalScrollRange())) {
                ViewCompat.stopNestedScroll(target, ViewCompat.TYPE_NON_TOUCH);
            }
        }
    }
}
