Retry strategy if download failed due to network fluctuation

app/src/main/java/org/kiwix/kiwixmobile/nav/destination/library/OnlineLibraryFragment.kt

@@ -106,10 +106,18 @@ class OnlineLibraryFragment : BaseFragment(), FragmentActivityExtensions {
     LibraryAdapter(
       LibraryDelegate.BookDelegate(bookUtils, ::onBookItemClick),
       LibraryDelegate.DownloadDelegate {
-        dialogShower.show(
-          KiwixDialog.YesNoDialog.StopDownload,
-          { downloader.cancelDownload(it.downloadId) }
-        )
+        if (it.downloadState.toReadableState(requireActivity()).contains("Failed")) {
+          if (isNotConnected) {
+            noInternetSnackbar()
+          } else {
+            downloader.retryDownload(it.downloadId)
+          }
+        } else {
+          dialogShower.show(
+            KiwixDialog.YesNoDialog.StopDownload,
+            { downloader.cancelDownload(it.downloadId) }
+          )
+        }
       },
       LibraryDelegate.DividerDelegate
     )

app/src/main/java/org/kiwix/kiwixmobile/zim_manager/library_view/adapter/LibraryViewHolder.kt

@@ -99,6 +99,9 @@ sealed class LibraryViewHolder<in T : LibraryListItem>(containerView: View) :
       downloadProgress.progress = item.progress
       stop.setOnClickListener { clickAction.invoke(item) }
       downloadState.text = item.downloadState.toReadableState(containerView.context)
+      if (item.downloadState.toReadableState(containerView.context).contains("Failed")) {
+        clickAction.invoke(item)
+      }
       eta.text = item.readableEta
     }
   }

core/src/main/java/org/kiwix/kiwixmobile/core/downloader/DownloadRequester.kt

@@ -22,4 +22,5 @@ import org.kiwix.kiwixmobile.core.downloader.model.DownloadRequest
 interface DownloadRequester {
   fun enqueue(downloadRequest: DownloadRequest): Long
   fun cancel(downloadId: Long)
+  fun retryDownload(downloadId: Long)
 }

core/src/main/java/org/kiwix/kiwixmobile/core/downloader/Downloader.kt

@@ -22,4 +22,5 @@ import org.kiwix.kiwixmobile.core.entity.LibraryNetworkEntity
 interface Downloader {
   fun download(book: LibraryNetworkEntity.Book)
   fun cancelDownload(downloadId: Long)
+  fun retryDownload(downloadId: Long)
 }

core/src/main/java/org/kiwix/kiwixmobile/core/downloader/DownloaderImpl.kt

@@ -49,4 +49,8 @@ class DownloaderImpl @Inject constructor(
   override fun cancelDownload(downloadId: Long) {
     downloadRequester.cancel(downloadId)
   }
+
+  override fun retryDownload(downloadId: Long) {
+    downloadRequester.retryDownload(downloadId)
+  }
 }

core/src/main/java/org/kiwix/kiwixmobile/core/downloader/fetch/FetchDownloadRequester.kt

@@ -41,6 +41,10 @@ class FetchDownloadRequester @Inject constructor(
   override fun cancel(downloadId: Long) {
     fetch.delete(downloadId.toInt())
   }
+
+  override fun retryDownload(downloadId: Long) {
+    fetch.retry(downloadId.toInt())
+  }
 }
 
 private fun DownloadRequest.toFetchRequest(sharedPreferenceUtil: SharedPreferenceUtil) =