src/com/android/wallpaper/util/SurfaceViewUtils.kt

/*
 * Copyright (C) 2024 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.wallpaper.util

import android.os.Bundle
import android.os.Message
import android.view.SurfaceControlViewHost
import android.view.SurfaceHolder
import android.view.SurfaceView
import android.view.View
import android.view.ViewGroup

/** Util class to generate surface view requests and parse responses */
object SurfaceViewUtils {
    private const val KEY_HOST_TOKEN = "host_token"
    const val KEY_VIEW_WIDTH = "width"
    const val KEY_VIEW_HEIGHT = "height"
    private const val KEY_SURFACE_PACKAGE = "surface_package"
    private const val KEY_CALLBACK = "callback"
    const val KEY_WALLPAPER_COLORS = "wallpaper_colors"
    const val KEY_DISPLAY_ID = "display_id"

    /** Create a surface view request. */
    fun createSurfaceViewRequest(surfaceView: SurfaceView, extras: Bundle?) =
        Bundle().apply {
            putBinder(KEY_HOST_TOKEN, surfaceView.getHostToken())
            // TODO(b/305258307): Figure out why SurfaceView.getDisplay returns null in small
            //  preview
            surfaceView.display?.let { putInt(KEY_DISPLAY_ID, it.displayId) }
            putInt(KEY_VIEW_WIDTH, surfaceView.width)
            putInt(KEY_VIEW_HEIGHT, surfaceView.height)
            extras?.let { putAll(it) }
        }

    /** Return the surface package. */
    fun getSurfacePackage(bundle: Bundle): SurfaceControlViewHost.SurfacePackage? {
        return bundle.getParcelable(KEY_SURFACE_PACKAGE)
    }

    /** Return the message callback. */
    fun getCallback(bundle: Bundle): Message? {
        return bundle.getParcelable(KEY_CALLBACK)
    }

    /** Removes the view from its parent and attaches to the surface control */
    fun SurfaceView.attachView(view: View, newWidth: Int = width, newHeight: Int = height) {
        // Detach view from its parent, if the view has one
        (view.parent as ViewGroup?)?.removeView(view)
        val host = SurfaceControlViewHost(context, display, hostToken)
        host.setView(view, newWidth, newHeight)
        setChildSurfacePackage(checkNotNull(host.surfacePackage))
    }

    interface SurfaceCallback : SurfaceHolder.Callback {
        override fun surfaceCreated(holder: SurfaceHolder) {}

        override fun surfaceChanged(holder: SurfaceHolder, format: Int, width: Int, height: Int) {}

        override fun surfaceDestroyed(holder: SurfaceHolder) {}
    }
}