Inline download resume policy

android/app/src/main/java/com/audiobookshelf/app/managers/DownloadResumePolicy.kt

@@ -1,23 +0,0 @@
-package com.audiobookshelf.app.managers
-
-internal object DownloadResumePolicy {
-  enum class InitialAction { COMPLETE, RESTART, FULL_DOWNLOAD, RANGE_DOWNLOAD }
-
-  fun initialAction(existingBytes: Long, expectedSize: Long): InitialAction =
-          when {
-            expectedSize > 0L && existingBytes == expectedSize -> InitialAction.COMPLETE
-            expectedSize > 0L && existingBytes > expectedSize -> InitialAction.RESTART
-            existingBytes > 0L -> InitialAction.RANGE_DOWNLOAD
-            else -> InitialAction.FULL_DOWNLOAD
-          }
-
-  fun unsatisfiedRangeSize(contentRange: String?): Long? {
-    if (contentRange == null) return null
-    return UNSATISFIED_CONTENT_RANGE.matchEntire(contentRange)
-            ?.groupValues
-            ?.get(1)
-            ?.toLongOrNull()
-  }
-
-  private val UNSATISFIED_CONTENT_RANGE = Regex("bytes \\*/(\\d+)")
-}

android/app/src/main/java/com/audiobookshelf/app/managers/InternalDownloadManager.kt

@@ -61,21 +61,18 @@ class InternalDownloadManager(
           allowRestart: Boolean
   ) {
     var existingBytes = destinationFile.takeIf { it.exists() }?.length() ?: 0L
-    when (DownloadResumePolicy.initialAction(existingBytes, expectedSize)) {
+    if (expectedSize > 0L && existingBytes == expectedSize) {
-      DownloadResumePolicy.InitialAction.COMPLETE -> {
+      progressCallback.onProgress(existingBytes, 100L)
-        progressCallback.onProgress(existingBytes, 100L)
+      progressCallback.onComplete(false)
-        progressCallback.onComplete(false)
+      return
+    }
+    if (expectedSize > 0L && existingBytes > expectedSize) {
+      if (!destinationFile.delete()) {
+        Log.e(tag, "Could not delete oversized staging file ${destinationFile.name}")
+        progressCallback.onComplete(true)
         return
       }
-      DownloadResumePolicy.InitialAction.RESTART -> {
+      existingBytes = 0L
-        if (!destinationFile.delete()) {
-          Log.e(tag, "Could not delete oversized staging file ${destinationFile.name}")
-          progressCallback.onComplete(true)
-          return
-        }
-        existingBytes = 0L
-      }
-      else -> Unit
     }
     val request =
             Request.Builder()
@@ -98,8 +95,9 @@ class InternalDownloadManager(
                   try {
                     if (response.code == 416) {
                       val serverSize =
-                              DownloadResumePolicy.unsatisfiedRangeSize(
+                              response.header("Content-Range")
-                                      response.header("Content-Range"))
+                                      ?.removePrefix("bytes */")
+                                      ?.toLongOrNull()
                       if (serverSize != null && serverSize > 0L && existingBytes == serverSize) {
                         progressCallback.onProgress(existingBytes, 100L)
                         progressCallback.onComplete(false)

android/app/src/test/java/com/audiobookshelf/app/managers/DownloadResumePolicyTest.kt

@@ -1,41 +0,0 @@
-package com.audiobookshelf.app.managers
-
-import org.junit.Assert.assertEquals
-import org.junit.Assert.assertNull
-import org.junit.Test
-
-class DownloadResumePolicyTest {
-  @Test
-  fun completeKnownFileDoesNotIssueRequest() {
-    assertEquals(
-            DownloadResumePolicy.InitialAction.COMPLETE,
-            DownloadResumePolicy.initialAction(100L, 100L))
-  }
-
-  @Test
-  fun partialAndUnknownFilesUseRange() {
-    assertEquals(
-            DownloadResumePolicy.InitialAction.RANGE_DOWNLOAD,
-            DownloadResumePolicy.initialAction(25L, 100L))
-    assertEquals(
-            DownloadResumePolicy.InitialAction.RANGE_DOWNLOAD,
-            DownloadResumePolicy.initialAction(25L, 0L))
-  }
-
-  @Test
-  fun oversizedFileRestartsAndEmptyFileDownloadsFully() {
-    assertEquals(
-            DownloadResumePolicy.InitialAction.RESTART,
-            DownloadResumePolicy.initialAction(101L, 100L))
-    assertEquals(
-            DownloadResumePolicy.InitialAction.FULL_DOWNLOAD,
-            DownloadResumePolicy.initialAction(0L, 100L))
-  }
-
-  @Test
-  fun parsesUnsatisfiedContentRange() {
-    assertEquals(787913771L, DownloadResumePolicy.unsatisfiedRangeSize("bytes */787913771"))
-    assertNull(DownloadResumePolicy.unsatisfiedRangeSize("bytes 0-99/100"))
-    assertNull(DownloadResumePolicy.unsatisfiedRangeSize(null))
-  }
-}