/*
 * Copyright (C) 2025 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 com.android.systemui.car.wm.scalableui.view;

import android.annotation.SuppressLint;
import android.content.Context;
import android.graphics.Canvas;
import android.util.AttributeSet;
import android.view.View;

import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.constraintlayout.widget.ConstraintLayout;

/**
 * An overlay panel that can be used for blur effect or can be used to overlay a panel while in
 * split mode.
 */
public class PanelOverlay extends ConstraintLayout {

    /**
     * Callback for view's visibility changes.
     */
    public interface OnChangeListener {

        /**
         * Invoked when visibility changes.
         */
        void onVisibilityChange(int visibility);

        /**
         * Invoked when alpha changes.
         */
        void onAlphaChanged(float alpha);
    }

    private static final String TAG = PanelOverlay.class.getSimpleName();
    private OnChangeListener mOnChangeListener;

    /**
     * Constructor for GripBar.
     */
    public PanelOverlay(@NonNull Context context) {
        this(context, null);
        setVisibility(GONE);
    }

    public PanelOverlay(@NonNull Context context, @Nullable AttributeSet attrs) {
        this(context, attrs, 0);
    }

    public PanelOverlay(@NonNull Context context, @Nullable AttributeSet attrs,
            int defStyleAttr) {
        this(context, attrs, defStyleAttr, 0);
    }

    @SuppressLint("ClickableViewAccessibility")
    public PanelOverlay(@NonNull Context context, @Nullable AttributeSet attrs,
            int defStyleAttr,
            int defStyleRes) {
        super(context, attrs, defStyleAttr, defStyleRes);
    }

    public void setOnChangeListener(OnChangeListener listener) {
        mOnChangeListener = listener;
    }

    @Override
    protected void onVisibilityChanged(View changedView, int visibility) {
        super.onVisibilityChanged(changedView, visibility);
        mOnChangeListener.onVisibilityChange(visibility);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);

        if (mOnChangeListener != null) {
            mOnChangeListener.onAlphaChanged(getAlpha());
        }
    }
}