Resolve various memory leaks (#637)

This migrates the clipboard clear logic into a foreground service that allows us to also provide a notification that runs the clear task immediately on click, rather than wait for the timeout.

Co-authored-by: Aditya Wasan <adityawasan55@gmail.com>
Signed-off-by: Harsh Shandilya <me@msfjarvis.dev>

1 files changed, 156 insertions, 0 deletions

diff --git a/app/src/main/java/com/zeapo/pwdstore/ClipboardService.kt b/app/src/main/java/com/zeapo/pwdstore/ClipboardService.kt
new file mode 100644
index 00000000..c47444ba
--- /dev/null
+++ b/app/src/main/java/com/zeapo/pwdstore/ClipboardService.kt
@@ -0,0 +1,156 @@
+/*
+ * Copyright © 2014-2020 The Android Password Store Authors. All Rights Reserved.
+ * SPDX-License-Identifier: GPL-3.0-only
+ */
+package com.zeapo.pwdstore
+
+import android.app.NotificationChannel
+import android.app.NotificationManager
+import android.app.PendingIntent
+import android.app.Service
+import android.content.ClipboardManager
+import android.content.Intent
+import android.content.SharedPreferences
+import android.os.Build
+import android.os.IBinder
+import androidx.core.app.NotificationCompat
+import androidx.core.content.getSystemService
+import androidx.localbroadcastmanager.content.LocalBroadcastManager
+import androidx.preference.PreferenceManager
+import com.zeapo.pwdstore.utils.ClipboardUtils
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.Job
+import kotlinx.coroutines.cancel
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.isActive
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.withContext
+import timber.log.Timber
+
+class ClipboardService : Service() {
+
+    private val scope = CoroutineScope(Job() + Dispatchers.Main)
+    private val settings: SharedPreferences by lazy { PreferenceManager.getDefaultSharedPreferences(this) }
+
+    override fun onStartCommand(intent: Intent?, flags: Int, startId: Int): Int {
+        if (intent != null) {
+            when (intent.action) {
+                ACTION_CLEAR -> {
+                    clearClipboard()
+                    stopForeground(true)
+                    stopSelf()
+                    return super.onStartCommand(intent, flags, startId)
+                }
+
+                ACTION_START -> {
+                    val time = try {
+                        Integer.parseInt(settings.getString("general_show_time", "45") as String)
+                    } catch (e: NumberFormatException) {
+                        45
+                    }
+
+                    if (time == 0) {
+                        stopSelf()
+                    }
+
+                    createNotification()
+                    scope.launch {
+                        withContext(Dispatchers.IO) {
+                            startTimer(time)
+                        }
+                        withContext(Dispatchers.Main) {
+                            emitBroadcast()
+                            clearClipboard()
+                            stopForeground(true)
+                            stopSelf()
+                        }
+                    }
+                    return START_NOT_STICKY
+                }
+            }
+        }
+
+        return super.onStartCommand(intent, flags, startId)
+    }
+
+    override fun onBind(intent: Intent?): IBinder? {
+        return null
+    }
+
+    override fun onDestroy() {
+        scope.cancel()
+        super.onDestroy()
+    }
+
+    private fun clearClipboard() {
+        val deepClear = settings.getBoolean("clear_clipboard_20x", false)
+        val clipboardManager = getSystemService<ClipboardManager>()
+
+        if (clipboardManager is ClipboardManager) {
+            scope.launch {
+                ClipboardUtils.clearClipboard(clipboardManager, deepClear)
+            }
+        } else {
+            Timber.tag("ClipboardService").d("Cannot get clipboard manager service")
+        }
+    }
+
+    private suspend fun startTimer(showTime: Int) {
+        var current = 0
+        while (scope.isActive && current < showTime) {
+            // Block for 1s or until cancel is signalled
+            current++
+            delay(1000)
+        }
+    }
+
+    private fun emitBroadcast() {
+        val localBroadcastManager = LocalBroadcastManager.getInstance(this)
+        val clearIntent = Intent(ACTION_CLEAR)
+        localBroadcastManager.sendBroadcast(clearIntent)
+    }
+
+    private fun createNotification() {
+        createNotificationChannel()
+        val clearIntent = Intent(this, ClipboardService::class.java)
+        clearIntent.action = ACTION_CLEAR
+        val pendingIntent = if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
+            PendingIntent.getForegroundService(this, 0, clearIntent, PendingIntent.FLAG_UPDATE_CURRENT)
+        } else {
+            PendingIntent.getService(this, 0, clearIntent, PendingIntent.FLAG_UPDATE_CURRENT)
+        }
+
+        val notification = NotificationCompat.Builder(this, CHANNEL_ID)
+                .setContentTitle(getString(R.string.app_name))
+                .setContentText(getString(R.string.tap_clear_clipboard))
+                .setSmallIcon(R.drawable.ic_launcher_foreground)
+                .setContentIntent(pendingIntent)
+                .setUsesChronometer(true)
+                .setPriority(NotificationCompat.PRIORITY_LOW)
+                .build()
+
+        startForeground(1, notification)
+    }
+
+    private fun createNotificationChannel() {
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
+            val serviceChannel = NotificationChannel(
+                    CHANNEL_ID,
+                    getString(R.string.app_name),
+                    NotificationManager.IMPORTANCE_LOW
+            )
+            val manager = getSystemService<NotificationManager>()
+            if (manager != null) {
+                manager.createNotificationChannel(serviceChannel)
+            } else {
+                Timber.tag("ClipboardService").d("Failed to create notification channel")
+            }
+        }
+    }
+    companion object {
+        private const val ACTION_CLEAR = "ACTION_CLEAR_CLIPBOARD"
+        private const val ACTION_START = "ACTION_START_CLIPBOARD_TIMER"
+        private const val CHANNEL_ID = "NotificationService"
+    }
+}