feat(sftp): notify MediaStore on file changes

This commit adds functionality to notify the MediaStore when files are modified via SFTP. This ensures that
 changes made through SFTP are reflected in the Android media library.

Specifically, the MediaStore is notified after file creation, deletion, copying, renaming, and link creation. Additionally, it is notified after closing a file that was opened for writing. This ensures that the MediaStore is kept up-to-date
 with any changes made to files through SFTP.

src/org/kde/kdeconnect/Plugins/SftpPlugin/SimpleSftpServer.kt

@@ -7,6 +7,7 @@
 package org.kde.kdeconnect.Plugins.SftpPlugin
 
 import android.content.Context
+import android.net.Uri
 import android.os.Build
 import android.util.Log
 import org.apache.sshd.common.file.nativefs.NativeFileSystemFactory
@@ -26,6 +27,7 @@ import org.apache.sshd.sftp.server.SftpFileSystemAccessor
 import org.apache.sshd.sftp.server.SftpSubsystemFactory
 import org.apache.sshd.sftp.server.SftpSubsystemProxy
 import org.kde.kdeconnect.Device
+import org.kde.kdeconnect.Helpers.MediaStoreHelper
 import org.kde.kdeconnect.Helpers.RandomHelper
 import org.kde.kdeconnect.Helpers.SecurityHelpers.RsaHelper
 import org.kde.kdeconnect.Helpers.SecurityHelpers.constantTimeCompare
@@ -33,10 +35,13 @@ import org.kde.kdeconnect.Plugins.SftpPlugin.saf.SafFileSystemFactory
 import org.kde.kdeconnect.Plugins.SftpPlugin.saf.SafPath
 import org.slf4j.impl.HandroidLoggerAdapter
 import java.io.IOException
+import java.nio.channels.Channel
 import java.nio.channels.SeekableByteChannel
 import java.nio.charset.StandardCharsets
+import java.nio.file.CopyOption
 import java.nio.file.OpenOption
 import java.nio.file.Path
+import java.nio.file.StandardOpenOption
 import java.nio.file.attribute.FileAttribute
 import java.security.GeneralSecurityException
 import java.security.KeyPair
@@ -103,6 +108,17 @@ internal class SimpleSftpServer {
         sshd.subsystemFactories =
             listOf<SubsystemFactory>(SftpSubsystemFactory.Builder().apply {
                 withFileSystemAccessor(object : SftpFileSystemAccessor {
+                    fun notifyMediaStore(path: Path) {
+                        kotlin.runCatching {
+                            val uri = Uri.parse(path.toUri().toString())
+                            MediaStoreHelper.indexFile(context, uri)
+                            uri
+                        }.fold(
+                            onSuccess = { Log.i(TAG, "Notified media store: $path, $it") },
+                            onFailure = { Log.w(TAG, "Failed to notify media store: $path", it) }
+                        )
+                    }
+
                     override fun openFile(
                         subsystem: SftpSubsystemProxy?,
                         fileHandle: FileHandle?,
@@ -116,6 +132,61 @@ internal class SimpleSftpServer {
                         }
                         return super.openFile(subsystem, fileHandle, file, handle, options, *attrs)
                     }
+
+                    override fun removeFile(
+                        subsystem: SftpSubsystemProxy?,
+                        path: Path?,
+                        isDirectory: Boolean
+                    ) {
+                        super.removeFile(subsystem, path, isDirectory)
+                        path?.let { notifyMediaStore(it) }
+                    }
+
+                    override fun copyFile(
+                        subsystem: SftpSubsystemProxy?,
+                        src: Path?,
+                        dst: Path?,
+                        opts: MutableCollection<CopyOption>?
+                    ) {
+                        super.copyFile(subsystem, src, dst, opts)
+                        dst?.let { notifyMediaStore(it) }
+                    }
+
+                    override fun renameFile(
+                        subsystem: SftpSubsystemProxy?,
+                        oldPath: Path?,
+                        newPath: Path?,
+                        opts: MutableCollection<CopyOption>?
+                    ) {
+                        super.renameFile(subsystem, oldPath, newPath, opts)
+                        oldPath?.let { notifyMediaStore(it) }
+                        newPath?.let { notifyMediaStore(it) }
+                    }
+
+                    override fun createLink(
+                        subsystem: SftpSubsystemProxy?,
+                        link: Path?,
+                        existing: Path?,
+                        symLink: Boolean
+                    ) {
+                        super.createLink(subsystem, link, existing, symLink)
+                        link?.let { notifyMediaStore(it) }
+                        existing?.let { notifyMediaStore(it) }
+                    }
+
+                    override fun closeFile(
+                        subsystem: SftpSubsystemProxy?,
+                        fileHandle: FileHandle?,
+                        file: Path?,
+                        handle: String?,
+                        channel: Channel?,
+                        options: MutableSet<out OpenOption>?
+                    ) {
+                        super.closeFile(subsystem, fileHandle, file, handle, channel, options)
+                        if (options?.contains(StandardOpenOption.WRITE) == true) {
+                            file?.let { notifyMediaStore(it) }
+                        }
+                    }
                 })
             }.build())
 
@@ -189,8 +260,9 @@ internal class SimpleSftpServer {
     }
 
     companion object {
-        private val PORT_RANGE = 1739..1764
+        private const val TAG = "SimpleSftpServer"
 
+        private val PORT_RANGE = 1739..1764
         const val USER: String = "kdeconnect"
 
         init {

src/org/kde/kdeconnect/Plugins/SftpPlugin/saf/SafFileSystemProvider.kt

@@ -98,7 +98,6 @@ class SafFileSystemProvider(
         val docFile = parent.createFile(Files.probeContentType(path), path.names.last())
             ?: throw IOException("Failed to create $path")
         val uri = docFile.uri
-        MediaStoreHelper.indexFile(context, uri)
         path.safUri = uri
         return uri
     }
@@ -226,7 +225,6 @@ class SafFileSystemProvider(
         if (!docFile.delete()) {
             throw IOException("Failed to delete $path")
         }
-        MediaStoreHelper.indexFile(context, docFile.uri)
     }
 
     override fun copy(source: Path, target: Path, vararg options: CopyOption) {
@@ -272,8 +270,6 @@ class SafFileSystemProvider(
                     if (newUri == null) { // renameDocument returns null on failure
                         return@firstStep
                     }
-                    MediaStoreHelper.indexFile(context, sourceUri)
-                    MediaStoreHelper.indexFile(context, newUri)
                     source.safUri = newUri
                     return
                 } catch (ignored: FileNotFoundException) {
@@ -295,8 +291,6 @@ class SafFileSystemProvider(
                 parentUri,
                 destParentUri
             )
-            MediaStoreHelper.indexFile(context, sourceUri)
-            MediaStoreHelper.indexFile(context, newUri)
             source.safUri = newUri!!
             return
         }

src/org/kde/kdeconnect/Plugins/SftpPlugin/saf/SafPath.kt

@@ -7,9 +7,9 @@ package org.kde.kdeconnect.Plugins.SftpPlugin.saf
 
 import android.content.Context
 import android.net.Uri
-import android.util.Log
 import androidx.documentfile.provider.DocumentFile
 import org.apache.sshd.common.file.util.BasePath
+import java.net.URI
 import java.nio.file.LinkOption
 
 class SafPath(
@@ -21,6 +21,10 @@ class SafPath(
         return this.normalize()
     }
 
+    override fun toUri(): URI {
+        return URI.create(safUri.toString()) ?: throw IllegalStateException("SafUri is null")
+    }
+
     fun getDocumentFile(ctx: Context): DocumentFile? {
         if (safUri == null) return null
         return DocumentFile.fromTreeUri(ctx, safUri!!)