Preserve Last Modification Date

data/src/apiKey/java/org/cryptomator/data/cloud/dropbox/DropboxCloudNodeFactory.kt

@@ -7,7 +7,7 @@ import com.dropbox.core.v2.files.Metadata
 internal object DropboxCloudNodeFactory {
 
 	fun from(parent: DropboxFolder, metadata: FileMetadata): DropboxFile {
-		return DropboxFile(parent, metadata.name, metadata.pathDisplay, metadata.size, metadata.serverModified)
+		return DropboxFile(parent, metadata.name, metadata.pathDisplay, metadata.size, metadata.clientModified)
 	}
 
 	@JvmStatic

data/src/apiKey/java/org/cryptomator/data/cloud/dropbox/DropboxImpl.kt

@@ -39,6 +39,7 @@ import org.cryptomator.util.file.LruFileCacheUtil.Companion.retrieveFromLruCache
 import java.io.File
 import java.io.IOException
 import java.io.OutputStream
+import java.util.Date
 import timber.log.Timber
 
 internal class DropboxImpl(cloud: DropboxCloud, context: Context) {
@@ -167,6 +168,7 @@ internal class DropboxImpl(cloud: DropboxCloud, context: Context) {
 				client() //
 					.files() //
 					.uploadBuilder(file.path) //
+					.withClientModified(data.modifiedDate(context).orElse(Date())) //
 					.withMode(writeMode) //
 					.uploadAndFinish(it)
 			}

data/src/apiKey/java/org/cryptomator/data/cloud/onedrive/OnedriveCloudNodeFactory.kt

@@ -74,8 +74,7 @@ internal object OnedriveCloudNodeFactory {
 	}
 
 	private fun lastModified(item: DriveItem): Date? {
-		return item.lastModifiedDateTime?.let {
-			return Date.from(it.toInstant())
-		}
+		return item.fileSystemInfo?.lastModifiedDateTime?.let { clientDate -> Date.from(clientDate.toInstant()) }
+			?: item.lastModifiedDateTime?.let { serverDate -> Date.from(serverDate.toInstant()) }
 	}
 }

data/src/apiKey/java/org/cryptomator/data/cloud/onedrive/OnedriveImpl.kt

@@ -5,6 +5,7 @@ import com.microsoft.graph.http.GraphServiceException
 import com.microsoft.graph.models.DriveItem
 import com.microsoft.graph.models.DriveItemCreateUploadSessionParameterSet
 import com.microsoft.graph.models.DriveItemUploadableProperties
+import com.microsoft.graph.models.FileSystemInfo
 import com.microsoft.graph.models.Folder
 import com.microsoft.graph.models.ItemReference
 import com.microsoft.graph.options.Option
@@ -39,6 +40,8 @@ import org.cryptomator.util.file.LruFileCacheUtil.Companion.retrieveFromLruCache
 import java.io.File
 import java.io.IOException
 import java.io.OutputStream
+import java.time.OffsetDateTime
+import java.time.ZoneId
 import java.util.Date
 import java.util.concurrent.CompletableFuture
 import java.util.concurrent.ExecutionException
@@ -202,14 +205,21 @@ internal class OnedriveImpl(private val cloud: OnedriveCloud, private val client
 		}
 		progressAware.onProgress(Progress.completed(UploadState.upload(file)))
 		return try {
-			OnedriveCloudNodeFactory.file(file.parent, result.get(), Date())
+			val driveItem: DriveItem = result.get()
+			val lastModifiedDate = getLastModifiedDateTime(driveItem) ?: Date()
+			OnedriveCloudNodeFactory.file(file.parent, driveItem, lastModifiedDate)
 		} catch (e: ExecutionException) {
 			throw FatalBackendException(e)
 		} catch (e: InterruptedException) {
 			throw FatalBackendException(e)
 		}
 	}
 
+	private fun getLastModifiedDateTime(driveItem: DriveItem): Date? {
+		return driveItem.fileSystemInfo?.lastModifiedDateTime?.let { clientDate -> Date.from(clientDate.toInstant()) }
+			?: driveItem.lastModifiedDateTime?.let { serverDate -> Date.from(serverDate.toInstant()) }
+	}
+
 	@Throws(NoSuchCloudFileException::class)
 	private fun uploadFile(file: OnedriveFile, data: DataSource, progressAware: ProgressAware<UploadState>, result: CompletableFuture<DriveItem>, conflictBehaviorOption: Option, size: Long) {
 		data.open(context)?.use { inputStream ->
@@ -228,12 +238,26 @@ internal class OnedriveImpl(private val cloud: OnedriveCloud, private val client
 						.putAsync(CopyStream.toByteArray(it)) //
 						.whenComplete { driveItem, error ->
 							run {
-								if (error == null) {
+								val modifiedDate = data.modifiedDate(context)
+								if (error != null) {
+									result.completeExceptionally(error)
+									return@whenComplete
+								}
+								if (modifiedDate.isPresent) {
+									patchAsyncLastModifiedDate(parentNodeInfo, driveItem, modifiedDate.get())
+										.whenComplete { driveItem, error ->
+											if (error == null) {
+												progressAware.onProgress(Progress.completed(UploadState.upload(file)))
+												result.complete(driveItem)
+												cacheNodeInfo(file, driveItem)
+											} else {
+												result.completeExceptionally(error)
+											}
+										}
+								} else { // current date is the default, no need to patch()
 									progressAware.onProgress(Progress.completed(UploadState.upload(file)))
 									result.complete(driveItem)
 									cacheNodeInfo(file, driveItem)
-								} else {
-									result.completeExceptionally(error)
 								}
 							}
 						}
@@ -244,13 +268,32 @@ internal class OnedriveImpl(private val cloud: OnedriveCloud, private val client
 		} ?: throw FatalBackendException("InputStream shouldn't bee null")
 	}
 
+	private fun patchAsyncLastModifiedDate(parentNodeInfo: OnedriveIdCache.NodeInfo, driveItem: DriveItem, modifiedDate: Date): CompletableFuture<DriveItem> {
+		val diffItem = DriveItem()
+		diffItem.fileSystemInfo = FileSystemInfo()
+		diffItem.fileSystemInfo!!.lastModifiedDateTime = OffsetDateTime.ofInstant(modifiedDate.toInstant(), ZoneId.systemDefault())
+		return drive(parentNodeInfo.driveId) //
+			.items(driveItem.id!!) //
+			.buildRequest() //
+			.patchAsync(diffItem) //
+	}
+
 	@Throws(IOException::class, NoSuchCloudFileException::class)
 	private fun chunkedUploadFile(file: OnedriveFile, data: DataSource, progressAware: ProgressAware<UploadState>, result: CompletableFuture<DriveItem>, conflictBehaviorOption: Option, size: Long) {
 		val parentNodeInfo = requireNodeInfo(file.parent)
+
+		val props = DriveItemUploadableProperties()
+		val modifiedDate = data.modifiedDate(context)
+
+		if (modifiedDate.isPresent) {
+			props.fileSystemInfo = FileSystemInfo()
+			props.fileSystemInfo!!.lastModifiedDateTime = OffsetDateTime.ofInstant(modifiedDate.get().toInstant(), ZoneId.systemDefault())
+		}
+
 		drive(parentNodeInfo.driveId) //
 			.items(parentNodeInfo.id) //
 			.itemWithPath(file.name) //
-			.createUploadSession(DriveItemCreateUploadSessionParameterSet.newBuilder().withItem(DriveItemUploadableProperties()).build()) //
+			.createUploadSession(DriveItemCreateUploadSessionParameterSet.newBuilder().withItem(props).build()) //
 			.buildRequest() //
 			.post()?.let { uploadSession ->
 				data.open(context)?.use { inputStream ->

data/src/apiKey/java/org/cryptomator/data/cloud/pcloud/PCloudImpl.kt

@@ -208,7 +208,7 @@ internal class PCloudImpl(private val cloud: PCloud, private val client: ApiClie
 		}
 		return try {
 			client //
-				.createFile(file.parent.path, file.name, pCloudDataSource, Date(), listener, uploadOptions) //
+				.createFile(file.parent.path, file.name, pCloudDataSource, data.modifiedDate(context).orElse(Date()), listener, uploadOptions) //
 				.execute()
 		} catch (ex: ApiError) {
 			handleApiError(ex, file.name)

data/src/apkStorePlaystore/java/org/cryptomator/data/cloud/googledrive/GoogleDriveImpl.kt

@@ -3,6 +3,7 @@ package org.cryptomator.data.cloud.googledrive
 import android.content.Context
 import com.google.api.client.googleapis.json.GoogleJsonResponseException
 import com.google.api.client.http.HttpResponseException
+import com.google.api.client.util.DateTime
 import com.google.api.services.drive.Drive
 import com.google.api.services.drive.model.File
 import com.google.api.services.drive.model.Revision
@@ -25,6 +26,7 @@ import org.cryptomator.util.file.LruFileCacheUtil
 import org.cryptomator.util.file.LruFileCacheUtil.Companion.retrieveFromLruCache
 import java.io.IOException
 import java.io.OutputStream
+import java.util.Date
 import timber.log.Timber
 
 internal class GoogleDriveImpl(context: Context, googleDriveCloud: GoogleDriveCloud, idCache: GoogleDriveIdCache) {
@@ -203,6 +205,7 @@ internal class GoogleDriveImpl(context: Context, googleDriveCloud: GoogleDriveCl
 		val metadata = File()
 		metadata.name = file.name
 		progressAware.onProgress(Progress.started(UploadState.upload(file)))
+		metadata.setModifiedTime(DateTime(data.modifiedDate(context).orElse(Date())))
 		val uploadedFile = if (file.driveId != null && replace) {
 			updateFile(file, data, progressAware, size, metadata)
 		} else {

data/src/main/java/org/cryptomator/data/cloud/crypto/CryptoImplDecorator.kt

@@ -449,6 +449,7 @@ abstract class CryptoImplDecorator(
 								progressAware.onProgress(Progress.progress(UploadState.encryption(cryptoFile)).between(0).and(ciphertextSize).withValue(encrypted))
 							}
 							encryptingWritableByteChannel.close()
+							data.modifiedDate(context).ifPresent { encryptedTmpFile.setLastModified(it.time) }
 							progressAware.onProgress(Progress.completed(UploadState.encryption(cryptoFile)))
 							return writeFromTmpFile(data, cryptoFile, encryptedTmpFile, progressAware, replace)
 						}

data/src/main/java/org/cryptomator/data/cloud/crypto/CryptoImplVaultFormat7.kt

@@ -486,6 +486,7 @@ open class CryptoImplVaultFormat7 : CryptoImplDecorator {
 									progressAware.onProgress(Progress.progress(UploadState.encryption(cloudFile)).between(0).and(ciphertextSize).withValue(encrypted))
 								}
 								encryptingWritableByteChannel.close()
+								data.modifiedDate(context).ifPresent { encryptedTmpFile.setLastModified(it.time) }
 								progressAware.onProgress(Progress.completed(UploadState.encryption(cloudFile)))
 								val targetFile = targetFile(cryptoFile, cloudFile, replace)
 								return file(

data/src/main/java/org/cryptomator/data/cloud/webdav/WebDavImpl.kt

@@ -23,6 +23,7 @@ import org.cryptomator.domain.usecases.cloud.Progress
 import org.cryptomator.domain.usecases.cloud.UploadState
 import java.io.IOException
 import java.io.OutputStream
+import java.util.Date
 import okhttp3.HttpUrl.Companion.toHttpUrlOrNull
 
 internal class WebDavImpl(private val cloud: WebDavCloud, private val connectionHandler: ConnectionHandlerHandlerImpl, private val context: Context) {
@@ -133,7 +134,7 @@ internal class WebDavImpl(private val cloud: WebDavCloud, private val connection
 					)
 				}
 			}.use {
-				connectionHandler.writeFile(absoluteUriFrom(uploadFile.path), it)
+				connectionHandler.writeFile(absoluteUriFrom(uploadFile.path), it, data.modifiedDate(context).orElse(Date()))
 			}
 		} ?: throw FatalBackendException("InputStream shouldn't bee null")
 

data/src/main/java/org/cryptomator/data/cloud/webdav/network/ConnectionHandlerHandlerImpl.kt

@@ -5,6 +5,7 @@ import org.cryptomator.data.cloud.webdav.WebDavNode
 import org.cryptomator.domain.CloudFolder
 import org.cryptomator.domain.exception.BackendException
 import java.io.InputStream
+import java.util.Date
 import javax.inject.Inject
 
 class ConnectionHandlerHandlerImpl @Inject internal constructor(httpClient: WebDavCompatibleHttpClient) {
@@ -27,8 +28,8 @@ class ConnectionHandlerHandlerImpl @Inject internal constructor(httpClient: WebD
 	}
 
 	@Throws(BackendException::class)
-	fun writeFile(url: String, inputStream: InputStream) {
-		webDavClient.writeFile(url, inputStream)
+	fun writeFile(url: String, inputStream: InputStream, modifiedDate: Date) {
+		webDavClient.writeFile(url, inputStream, modifiedDate)
 	}
 
 	@Throws(BackendException::class)

data/src/main/java/org/cryptomator/data/cloud/webdav/network/WebDavClient.kt

@@ -18,6 +18,7 @@ import java.io.IOException
 import java.io.InputStream
 import java.net.HttpURLConnection
 import java.util.Collections
+import java.util.Date
 import okhttp3.MediaType.Companion.toMediaTypeOrNull
 import okhttp3.Request
 import okhttp3.RequestBody.Companion.toRequestBody
@@ -150,8 +151,9 @@ internal class WebDavClient(private val httpClient: WebDavCompatibleHttpClient)
 	}
 
 	@Throws(BackendException::class)
-	fun writeFile(url: String, inputStream: InputStream) {
+	fun writeFile(url: String, inputStream: InputStream, modifiedDate: Date) {
 		val builder = Request.Builder() //
+			.addHeader("X-OC-Mtime", modifiedDate.toInstant().toEpochMilli().div(1000).toString()) //
 			.put(InputStreamSourceBasedRequestBody.from(inputStream)) //
 			.url(url)
 		try {

domain/src/main/java/org/cryptomator/domain/usecases/cloud/ByteArrayDataSource.kt

@@ -1,9 +1,11 @@
 package org.cryptomator.domain.usecases.cloud
 
 import android.content.Context
+import org.cryptomator.util.Optional
 import java.io.ByteArrayInputStream
 import java.io.IOException
 import java.io.InputStream
+import java.util.Date
 
 class ByteArrayDataSource private constructor(private val bytes: ByteArray) : DataSource {
 
@@ -25,6 +27,10 @@ class ByteArrayDataSource private constructor(private val bytes: ByteArray) : Da
 		// do nothing because ByteArrayInputStream need no close
 	}
 
+	override fun modifiedDate(context: Context): Optional<Date> {
+		return Optional.empty()
+	}
+
 	companion object {
 
 		@JvmStatic

domain/src/main/java/org/cryptomator/domain/usecases/cloud/CancelAwareDataSource.kt

@@ -2,8 +2,10 @@ package org.cryptomator.domain.usecases.cloud
 
 import android.content.Context
 import org.cryptomator.domain.exception.CancellationException
+import org.cryptomator.util.Optional
 import java.io.IOException
 import java.io.InputStream
+import java.util.Date
 
 class CancelAwareDataSource private constructor(private val delegate: DataSource, private val cancelled: Flag) : DataSource {
 
@@ -31,6 +33,13 @@ class CancelAwareDataSource private constructor(private val delegate: DataSource
 		delegate.close()
 	}
 
+	override fun modifiedDate(context: Context): Optional<Date> {
+		if (cancelled.get()) {
+			throw CancellationException()
+		}
+		return delegate.modifiedDate(context)
+	}
+
 	companion object {
 
 		@JvmStatic

domain/src/main/java/org/cryptomator/domain/usecases/cloud/DataSource.kt

@@ -1,10 +1,12 @@
 package org.cryptomator.domain.usecases.cloud
 
 import android.content.Context
+import org.cryptomator.util.Optional
 import java.io.Closeable
 import java.io.IOException
 import java.io.InputStream
 import java.io.Serializable
+import java.util.Date
 
 interface DataSource : Serializable, Closeable {
 
@@ -15,4 +17,6 @@ interface DataSource : Serializable, Closeable {
 
 	fun decorate(delegate: DataSource): DataSource
 
+	fun modifiedDate(context: Context): Optional<Date>
+
 }

domain/src/main/java/org/cryptomator/domain/usecases/cloud/FileBasedDataSource.kt

@@ -1,10 +1,12 @@
 package org.cryptomator.domain.usecases.cloud
 
 import android.content.Context
+import org.cryptomator.util.Optional
 import java.io.File
 import java.io.FileInputStream
 import java.io.IOException
 import java.io.InputStream
+import java.util.Date
 
 class FileBasedDataSource private constructor(private val file: File) : DataSource {
 
@@ -26,6 +28,10 @@ class FileBasedDataSource private constructor(private val file: File) : DataSour
 		// Do nothing
 	}
 
+	override fun modifiedDate(context: Context): Optional<Date> {
+		return Optional.of(Date(file.lastModified()))
+	}
+
 	companion object {
 
 		@JvmStatic

domain/src/main/java/org/cryptomator/domain/usecases/cloud/UploadFiles.java

@@ -105,6 +105,7 @@ private File copyDataToFile(DataSource dataSource) {
 			InputStream in = CancelAwareDataSource.wrap(dataSource, cancelledFlag).open(context);
 			OutputStream out = new FileOutputStream(target);
 			copy(in, out);
+			dataSource.modifiedDate(context).ifPresent(value -> target.setLastModified(value.getTime()));
 			return target;
 		} catch (IOException e) {
 			throw new FatalBackendException(e);

domain/src/test/java/org/cryptomator/domain/usecases/cloud/UploadFileTest.kt

@@ -8,6 +8,7 @@ import org.cryptomator.domain.CloudNode
 import org.cryptomator.domain.exception.BackendException
 import org.cryptomator.domain.repository.CloudContentRepository
 import org.cryptomator.domain.usecases.ProgressAware
+import org.cryptomator.util.Optional
 import org.hamcrest.CoreMatchers
 import org.hamcrest.MatcherAssert
 import org.junit.jupiter.params.ParameterizedTest
@@ -21,6 +22,7 @@ import java.io.ByteArrayInputStream
 import java.io.IOException
 import java.io.InputStream
 import java.util.Arrays
+import java.util.Date
 
 class UploadFileTest {
 
@@ -105,6 +107,10 @@ class UploadFileTest {
 				return delegate
 			}
 
+			override fun modifiedDate(context: Context): Optional<Date> {
+				return Optional.of(Date())
+			}
+
 			@Throws(IOException::class)
 			override fun close() {
 				// do nothing

presentation/src/main/java/org/cryptomator/presentation/presenter/UriBasedDataSource.kt

@@ -4,8 +4,10 @@ import android.content.Context
 import android.net.Uri
 import org.cryptomator.domain.usecases.cloud.DataSource
 import org.cryptomator.presentation.util.ContentResolverUtil
+import org.cryptomator.util.Optional
 import java.io.IOException
 import java.io.InputStream
+import java.util.Date
 
 class UriBasedDataSource private constructor(private val uri: Uri) : DataSource {
 
@@ -27,6 +29,10 @@ class UriBasedDataSource private constructor(private val uri: Uri) : DataSource
 		// do nothing
 	}
 
+	override fun modifiedDate(context: Context): Optional<Date> {
+		return Optional.ofNullable(ContentResolverUtil(context).fileModifiedDate(uri))
+	}
+
 	companion object {
 
 		@JvmStatic