DownloadWorker: Progress improvements

* Handle split apk download progress
* Also share download speed and time remaining

Signed-off-by: Aayush Gupta <aayushgupta219@gmail.com>

app/src/main/java/com/aurora/extensions/InputStream.kt

@@ -1,24 +1,37 @@
 package com.aurora.extensions
 
+import com.aurora.store.data.model.DownloadInfo
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.flow.Flow
-import kotlinx.coroutines.flow.distinctUntilChanged
 import kotlinx.coroutines.flow.flow
 import kotlinx.coroutines.flow.flowOn
 import java.io.InputStream
 import java.io.OutputStream
+import kotlinx.coroutines.flow.distinctUntilChangedBy
+import kotlin.concurrent.fixedRateTimer
 
-fun InputStream.copyTo(out: OutputStream, streamSize: Long): Flow<Int> {
+fun InputStream.copyTo(out: OutputStream, streamSize: Long): Flow<DownloadInfo> {
     return flow {
         var bytesCopied: Long = 0
         val buffer = ByteArray(DEFAULT_BUFFER_SIZE)
         var bytes = read(buffer)
+
+        var lastTotalBytesRead = 0L
+        var speed: Long = 0
+        @Suppress("KotlinConstantConditions") // False-positive for bytesCopied always being zero
+        val timer = fixedRateTimer("timer", true, 0L, 1000) {
+            val totalBytesRead = bytesCopied
+            speed = totalBytesRead - lastTotalBytesRead
+            lastTotalBytesRead = totalBytesRead
+        }
+
         while (bytes >= 0) {
             out.write(buffer, 0, bytes)
             bytesCopied += bytes
-            bytes = read(buffer)
             // Emit stream progress in percentage
-            emit((bytesCopied * 100 / streamSize).toInt())
+            emit(DownloadInfo((bytesCopied * 100 / streamSize).toInt(), bytesCopied, speed))
+            bytes = read(buffer)
         }
-    }.flowOn(Dispatchers.IO).distinctUntilChanged()
+        timer.cancel()
+    }.flowOn(Dispatchers.IO).distinctUntilChangedBy { it.progress }
 }