diff --git a/app/src/main/kotlin/com/hippo/ehviewer/spider/SpiderDen.kt b/app/src/main/kotlin/com/hippo/ehviewer/spider/SpiderDen.kt
index 4bb8f8614..a522ca8da 100644
--- a/app/src/main/kotlin/com/hippo/ehviewer/spider/SpiderDen.kt
+++ b/app/src/main/kotlin/com/hippo/ehviewer/spider/SpiderDen.kt
@@ -42,6 +42,7 @@ import com.hippo.ehviewer.util.FileUtils
 import com.hippo.ehviewer.util.sendTo
 import com.hippo.unifile.UniFile
 import com.hippo.unifile.asUniFile
+import com.hippo.unifile.ensureDirOrThrow
 import com.hippo.unifile.openOutputStream
 import com.hippo.unifile.sha1
 import eu.kanade.tachiyomi.util.system.logcat
@@ -79,10 +80,10 @@ class SpiderDen(val info: GalleryInfo) {
         mode = value
         if (mode == SpiderQueen.MODE_DOWNLOAD) {
             if (downloadDir == null) {
-                downloadDir = getGalleryDownloadDir(gid)?.takeIf { it.ensureDir() }
+                downloadDir = getGalleryDownloadDir(gid)!!.apply { ensureDirOrThrow() }
             }
             if (saveAsCbz && tempDownloadDir == null) {
-                tempDownloadDir = info.tempDownloadDir?.takeIf { it.ensureDir() }
+                tempDownloadDir = info.tempDownloadDir!!.apply { ensureDirOrThrow() }
             }
         }
     }
@@ -306,7 +307,7 @@ class SpiderDen(val info: GalleryInfo) {
 
     suspend fun initDownloadDir() {
         downloadDir = getGalleryDownloadDir(gid) ?: (downloadLocation / info.putToDownloadDir())
-        check(downloadDir!!.ensureDir())
+        downloadDir!!.ensureDirOrThrow()
     }
 
     suspend fun writeComicInfo(fetchMetadata: Boolean = true) {
diff --git a/app/src/main/kotlin/com/hippo/ehviewer/util/FileUtils.kt b/app/src/main/kotlin/com/hippo/ehviewer/util/FileUtils.kt
index 6dfa5bcec..f359708c4 100644
--- a/app/src/main/kotlin/com/hippo/ehviewer/util/FileUtils.kt
+++ b/app/src/main/kotlin/com/hippo/ehviewer/util/FileUtils.kt
@@ -118,10 +118,10 @@ object FileUtils {
                 }
             }
             if (sizeInBytes > MAX_FILENAME_BYTES) {
-                do {
+                while (sizeInBytes > MAX_FILENAME_BYTES - 3) {
                     deleteCharAt(length / 2)
-                } while (sizeInBytes >= MAX_FILENAME_BYTES)
-                insert(length / 2, '…')
+                }
+                insert(length / 2, "...")
             }
         }
     }
diff --git a/app/src/main/kotlin/com/hippo/unifile/UniFileExtensions.kt b/app/src/main/kotlin/com/hippo/unifile/UniFileExtensions.kt
index c6c726f03..d9b0c4dbf 100644
--- a/app/src/main/kotlin/com/hippo/unifile/UniFileExtensions.kt
+++ b/app/src/main/kotlin/com/hippo/unifile/UniFileExtensions.kt
@@ -46,3 +46,6 @@ val Uri.displayPath: String?
         }
         return toString()
     }
+
+fun UniFile.ensureDirOrThrow() =
+    check(ensureDir()) { "Failed to create directory: ${uri.displayPath}" }