Delete downloaded file on failure

import android.content.ContentValues

import android.content.Context

import android.net.Uri

import android.os.Build

import android.os.Environment

import android.os.Handler

import io.heckel.ntfy.app.Application

import io.heckel.ntfy.data.*

import io.heckel.ntfy.util.queryFilename

import kotlinx.coroutines.delay

import okhttp3.OkHttpClient

import okhttp3.Request

import java.io.File

        .writeTimeout(15, TimeUnit.SECONDS)

        .build()

    private val notifier = NotificationService(context)

    private var uri: Uri? = null

    override fun doWork(): Result {

        if (context.applicationContext !is Application) return Result.failure()

        return Result.success()

    }

    override fun onStopped() {

        val uriCopy = uri

        if (uriCopy != null) {

            val resolver = applicationContext.contentResolver

            resolver.delete(uriCopy, null, null)

        }

    }

    private fun downloadAttachment(repository: Repository, subscription: Subscription, notification: Notification) {

        val attachment = notification.attachment ?: return

        Log.d(TAG, "Downloading attachment from ${attachment.url}")

                    resolver.insert(MediaStore.Files.getContentUri(MediaStore.VOLUME_EXTERNAL), details)

                        ?: throw Exception("Cannot get content URI")

                }

                this.uri = uri // Required for cleanup in onStopped()

                Log.d(TAG, "Starting download to content URI: $uri")

                var bytesCopied: Long = 0

                val out = resolver.openOutputStream(uri) ?: throw Exception("Cannot open output stream")

                                val newNotification = notification.copy(attachment = newAttachment)

                                notifier.update(subscription, newNotification)

                                repository.updateNotification(newNotification)

                                return

                                return // File will be deleted in onStopped()

                            }

                            val progress = if (size > 0) (bytesCopied.toFloat()/size.toFloat()*100).toInt() else PROGRESS_INDETERMINATE

                            val newAttachment = attachment.copy(progress = progress)