Merge pull request #7344 from hayaksi1/fix/6371-save-file-name-conflicts

Keep saving files to Downloads once 32 files share the same name

features/viewfolder/impl/src/main/kotlin/io/element/android/features/viewfolder/impl/file/FileSave.kt

@@ -16,6 +16,7 @@ import android.provider.MediaStore
 import androidx.annotation.RequiresApi
 import dev.zacsweers.metro.AppScope
 import dev.zacsweers.metro.ContributesBinding
+import io.element.android.libraries.androidutils.file.saveWithUniqueFileName
 import io.element.android.libraries.androidutils.system.toast
 import io.element.android.libraries.core.coroutine.CoroutineDispatchers
 import io.element.android.libraries.core.extensions.runCatchingExceptions
@@ -25,6 +26,7 @@ import kotlinx.coroutines.withContext
 import timber.log.Timber
 import java.io.File
 import java.io.FileOutputStream
+import java.io.IOException
 
 interface FileSave {
     suspend fun save(
@@ -61,18 +63,18 @@ class DefaultFileSave(
     @RequiresApi(Build.VERSION_CODES.Q)
     private fun saveOnDiskUsingMediaStore(path: String) {
         val file = File(path)
-        val contentValues = ContentValues().apply {
-            put(MediaStore.MediaColumns.DISPLAY_NAME, file.name)
-            put(MediaStore.MediaColumns.MIME_TYPE, MimeTypes.OctetStream)
-            put(MediaStore.MediaColumns.RELATIVE_PATH, Environment.DIRECTORY_DOWNLOADS)
-        }
         val resolver = context.contentResolver
-        val outputUri = resolver.insert(MediaStore.Downloads.EXTERNAL_CONTENT_URI, contentValues)
-        if (outputUri != null) {
-            file.inputStream().use { input ->
-                resolver.openOutputStream(outputUri).use { output ->
-                    input.copyTo(output!!, DEFAULT_BUFFER_SIZE)
-                }
+        val outputUri = saveWithUniqueFileName(file.name) { displayName ->
+            val contentValues = ContentValues().apply {
+                put(MediaStore.MediaColumns.DISPLAY_NAME, displayName)
+                put(MediaStore.MediaColumns.MIME_TYPE, MimeTypes.OctetStream)
+                put(MediaStore.MediaColumns.RELATIVE_PATH, Environment.DIRECTORY_DOWNLOADS)
+            }
+            resolver.insert(MediaStore.Downloads.EXTERNAL_CONTENT_URI, contentValues)
+        } ?: throw IOException("Unable to create the destination file")
+        file.inputStream().use { input ->
+            resolver.openOutputStream(outputUri).use { output ->
+                input.copyTo(output!!, DEFAULT_BUFFER_SIZE)
             }
         }
     }

features/viewfolder/impl/src/test/kotlin/io/element/android/features/viewfolder/impl/file/DefaultFileSaveTest.kt

@@ -0,0 +1,60 @@
+/*
+ * Copyright (c) 2026 Element Creations Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.features.viewfolder.impl.file
+
+import com.google.common.truth.Truth.assertThat
+import io.element.android.tests.testutils.fake.registerFakeMediaStoreContentProvider
+import io.element.android.tests.testutils.robolectric.RobolectricTest
+import io.element.android.tests.testutils.testCoroutineDispatchers
+import kotlinx.coroutines.test.TestScope
+import kotlinx.coroutines.test.runTest
+import org.junit.Test
+import org.robolectric.RuntimeEnvironment
+import java.io.File
+
+class DefaultFileSaveTest : RobolectricTest() {
+    @Test
+    fun `save inserts the file in the Downloads collection under its own name`() = runTest {
+        val mediaStore = registerFakeMediaStoreContentProvider()
+        createFileSave().save(aFileToSave().path)
+        assertThat(mediaStore.insertedDisplayNames).containsExactly("a-file.txt")
+        assertThat(mediaStore.savedContent("a-file.txt")).isEqualTo("Some content")
+    }
+
+    @Test
+    fun `save retries with a suffixed name when the name cannot be made unique`() = runTest {
+        val mediaStore = registerFakeMediaStoreContentProvider().apply {
+            conflictingDisplayNames = setOf("a-file.txt")
+        }
+        createFileSave().save(aFileToSave().path)
+        assertThat(mediaStore.insertedDisplayNames).hasSize(2)
+        assertThat(mediaStore.insertedDisplayNames.last()).matches("a-file_\\d+\\.txt")
+        assertThat(mediaStore.savedContent(mediaStore.insertedDisplayNames.last())).isEqualTo("Some content")
+    }
+
+    @Test
+    fun `save writes nothing when the destination cannot be created`() = runTest {
+        val mediaStore = registerFakeMediaStoreContentProvider().apply {
+            returnsNoUriOnInsert = true
+        }
+        createFileSave().save(aFileToSave().path)
+        assertThat(mediaStore.insertedDisplayNames).containsExactly("a-file.txt")
+        assertThat(mediaStore.savedFileNames()).isEmpty()
+    }
+
+    private fun aFileToSave(): File {
+        return File(RuntimeEnvironment.getApplication().cacheDir, "a-file.txt").apply {
+            writeText("Some content")
+        }
+    }
+
+    private fun TestScope.createFileSave() = DefaultFileSave(
+        context = RuntimeEnvironment.getApplication(),
+        dispatchers = testCoroutineDispatchers(),
+    )
+}