viewcapturelib/src/com/android/app/viewcapture/SettingsAwareViewCapture.kt

/*
 * Copyright (C) 2023 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.app.viewcapture

import android.content.Context
import android.content.pm.LauncherApps
import android.database.ContentObserver
import android.os.Handler
import android.os.ParcelFileDescriptor
import android.provider.Settings
import android.util.Log
import android.window.IDumpCallback
import androidx.annotation.AnyThread
import androidx.annotation.VisibleForTesting
import java.util.concurrent.Executor

private val TAG = SettingsAwareViewCapture::class.java.simpleName

/**
 * ViewCapture that listens to system updates and enables / disables attached ViewCapture
 * WindowListeners accordingly. The Settings toggle is currently controlled by the Winscope
 * developer tile in the System developer options.
 */
internal class SettingsAwareViewCapture
internal constructor(private val context: Context, executor: Executor) :
    ViewCapture(DEFAULT_MEMORY_SIZE, DEFAULT_INIT_POOL_SIZE, executor) {
    /** Dumps all the active view captures to the wm trace directory via LauncherAppService */
    private val mDumpCallback: IDumpCallback.Stub = object : IDumpCallback.Stub() {
        override fun onDump(out: ParcelFileDescriptor) {
            try {
                ParcelFileDescriptor.AutoCloseOutputStream(out).use { os -> dumpTo(os, context) }
            } catch (e: Exception) {
                Log.e(TAG, "failed to dump data to wm trace", e)
            }
        }
    }

    init {
        enableOrDisableWindowListeners()
        mBgExecutor.execute {
            context.contentResolver.registerContentObserver(
                    Settings.Global.getUriFor(VIEW_CAPTURE_ENABLED),
                    false,
                    object : ContentObserver(Handler()) {
                        override fun onChange(selfChange: Boolean) {
                            enableOrDisableWindowListeners()
                        }
                    })
        }
    }

    @AnyThread
    private fun enableOrDisableWindowListeners() {
        mBgExecutor.execute {
            val isEnabled = Settings.Global.getInt(context.contentResolver, VIEW_CAPTURE_ENABLED,
                    0) != 0
            MAIN_EXECUTOR.execute {
                enableOrDisableWindowListeners(isEnabled)
            }
            val launcherApps = context.getSystemService(LauncherApps::class.java)
            if (isEnabled) {
                launcherApps?.registerDumpCallback(mDumpCallback)
            } else {
                launcherApps?.unRegisterDumpCallback(mDumpCallback)
            }
        }
    }

    companion object {
        @VisibleForTesting internal const val VIEW_CAPTURE_ENABLED = "view_capture_enabled"
    }
}