feat(folders): implement copy_folders taking care of ownership

src/application/ports/file_ports.rs

@@ -334,6 +334,16 @@ pub trait FileManagementUseCase: Send + Sync + 'static {
             "copy_folder_tree not implemented",
         ))
     }
+
+    /// Copies a folder tree, enforcing that `caller_id` owns both the source folder
+    /// and the target parent folder.
+    async fn copy_folder_tree_owned(
+        &self,
+        source_folder_id: &str,
+        caller_id: Uuid,
+        target_parent_id: Option<String>,
+        dest_name: Option<String>,
+    ) -> Result<CopyFolderTreeResult, DomainError>;
 }
 
 /// Factory for creating file use case implementations

src/application/services/batch_operations.rs

@@ -12,6 +12,7 @@ use tracing::info;
 use crate::application::dtos::file_dto::FileDto;
 use crate::application::dtos::folder_dto::{FolderDto, MoveFolderDto};
 use crate::application::ports::file_ports::{FileManagementUseCase, FileRetrievalUseCase};
+use crate::application::ports::storage_ports::CopyFolderTreeResult;
 use crate::application::ports::inbound::FolderUseCase;
 use crate::application::ports::trash_ports::TrashUseCase;
 use crate::application::services::file_management_service::FileManagementService;
@@ -616,6 +617,73 @@ impl BatchOperationService {
         Ok(result)
     }
 
+    /// Copies multiple folder trees to a target parent in parallel
+    pub async fn copy_folders(
+        &self,
+        folder_ids: Vec<String>,
+        target_folder_id: Option<String>,
+        user_id: Uuid,
+    ) -> Result<BatchResult<CopyFolderTreeResult>, BatchOperationError> {
+        info!("Starting batch copy of {} folders", folder_ids.len());
+        let start_time = std::time::Instant::now();
+
+        let mut result = BatchResult {
+            successful: Vec::new(),
+            failed: Vec::new(),
+            stats: BatchStats {
+                total: folder_ids.len(),
+                ..Default::default()
+            },
+        };
+
+        let target: Option<Arc<str>> = target_folder_id.map(|s| Arc::from(s.as_str()));
+
+        let mut operation_stream = stream::iter(folder_ids.into_iter().map(|folder_id| {
+            let file_management = self.file_management.clone();
+            let target = target.clone();
+
+            async move {
+                let copy_result = file_management
+                    .copy_folder_tree_owned(
+                        &folder_id,
+                        user_id,
+                        target.map(|s| s.to_string()),
+                        None,
+                    )
+                    .await;
+                (folder_id, copy_result)
+            }
+        }))
+        .buffer_unordered(self.config.concurrency.max_concurrent_files);
+
+        while let Some((folder_id, operation_result)) = operation_stream.next().await {
+            match operation_result {
+                Ok(copy_result) => {
+                    result.successful.push(copy_result);
+                    result.stats.successful += 1;
+                }
+                Err(e) => {
+                    result.failed.push((folder_id, e.to_string()));
+                    result.stats.failed += 1;
+                }
+            }
+        }
+
+        result.stats.execution_time_ms = start_time.elapsed().as_millis();
+        result.stats.max_concurrency = self
+            .config
+            .concurrency
+            .max_concurrent_files
+            .min(result.stats.total);
+
+        info!(
+            "Batch folder copy completed: {}/{} successful in {}ms",
+            result.stats.successful, result.stats.total, result.stats.execution_time_ms
+        );
+
+        Ok(result)
+    }
+
     /// Downloads multiple files/folders as a single ZIP archive.
     ///
     /// Writes the archive to a temporary file so RAM usage is O(buffer_size)

src/application/services/file_management_service.rs

@@ -326,4 +326,31 @@ impl FileManagementUseCase for FileManagementService {
 
         Ok(result)
     }
+
+    async fn copy_folder_tree_owned(
+        &self,
+        source_folder_id: &str,
+        caller_id: Uuid,
+        target_parent_id: Option<String>,
+        dest_name: Option<String>,
+    ) -> Result<CopyFolderTreeResult, DomainError> {
+        if let Some(folder_repo) = &self.folder_repo {
+            let owner = folder_repo.get_folder_user_id(source_folder_id).await?;
+            if owner != caller_id {
+                return Err(DomainError::not_found(
+                    "Folder",
+                    "Source folder not found or access denied",
+                ));
+            }
+        } else {
+            return Err(DomainError::internal_error(
+                "FileManagement",
+                "Folder ownership verification unavailable",
+            ));
+        }
+        self.verify_target_folder_owner(&target_parent_id, caller_id)
+            .await?;
+        self.copy_folder_tree(source_folder_id, target_parent_id, dest_name)
+            .await
+    }
 }

src/common/stubs.rs

@@ -671,6 +671,19 @@ impl FileManagementUseCase for StubFileManagementUseCase {
     ) -> Result<FileDto, DomainError> {
         Ok(FileDto::default())
     }
+
+    async fn copy_folder_tree_owned(
+        &self,
+        _source_folder_id: &str,
+        _caller_id: Uuid,
+        _target_parent_id: Option<String>,
+        _dest_name: Option<String>,
+    ) -> Result<crate::application::ports::storage_ports::CopyFolderTreeResult, DomainError> {
+        Err(DomainError::internal_error(
+            "StubFileManagement",
+            "copy_folder_tree_owned not implemented",
+        ))
+    }
 }
 
 // ---------------------------------------------------------------------------

src/interfaces/api/handlers/batch_handler.rs

@@ -9,6 +9,7 @@ use utoipa::ToSchema;
 
 use crate::application::dtos::file_dto::FileDto;
 use crate::application::dtos::folder_dto::FolderDto;
+use crate::application::ports::storage_ports::CopyFolderTreeResult;
 use crate::application::services::batch_operations::{
     BatchOperationService, BatchResult, BatchStats,
 };
@@ -851,6 +852,90 @@ pub async fn move_folders_batch(
     Ok((status_code, Json(response)).into_response())
 }
 
+/// DTO returned for each successfully copied folder tree
+#[derive(Debug, Serialize, ToSchema)]
+pub struct CopiedFolderDto {
+    /// UUID of the newly created root folder
+    pub new_root_folder_id: String,
+    /// Total folders created (including root)
+    pub folders_copied: i64,
+    /// Total files copied (zero-copy via dedup)
+    pub files_copied: i64,
+}
+
+impl From<CopyFolderTreeResult> for CopiedFolderDto {
+    fn from(r: CopyFolderTreeResult) -> Self {
+        Self {
+            new_root_folder_id: r.new_root_folder_id,
+            folders_copied: r.folders_copied,
+            files_copied: r.files_copied,
+        }
+    }
+}
+
+/// Handler for copying multiple folder trees in batch
+#[utoipa::path(
+    post,
+    path = "/api/batch/folders/copy",
+    responses(
+        (status = 200, description = "All folders copied"),
+        (status = 206, description = "Partial success"),
+        (status = 400, description = "Bad request"),
+        (status = 401, description = "Unauthorized")
+    ),
+    tag = "batch"
+)]
+pub async fn copy_folders_batch(
+    State(state): State<BatchHandlerState>,
+    auth_user: AuthUser,
+    Json(request): Json<BatchFolderOperationRequest>,
+) -> ApiResult<impl IntoResponse> {
+    if request.folder_ids.is_empty() {
+        return Ok((
+            StatusCode::BAD_REQUEST,
+            Json(serde_json::json!({
+                "error": "No folder IDs provided"
+            })),
+        )
+            .into_response());
+    }
+    if request.folder_ids.len() > MAX_BATCH_SIZE {
+        return Ok((
+            StatusCode::BAD_REQUEST,
+            Json(serde_json::json!({
+                "error": format!("Batch size {} exceeds maximum of {}", request.folder_ids.len(), MAX_BATCH_SIZE)
+            })),
+        )
+            .into_response());
+    }
+
+    let result = state
+        .batch_service
+        .copy_folders(request.folder_ids, request.target_folder_id, auth_user.id)
+        .await
+        .map_err(|e| {
+            tracing::error!("Batch copy_folders failed: {}", e);
+            (
+                StatusCode::INTERNAL_SERVER_ERROR,
+                "Batch operation failed".to_string(),
+            )
+        })?;
+
+    let response: BatchOperationResponse<CopiedFolderDto> = result.into();
+
+    let status_code = if response.stats.failed > 0 {
+        if response.stats.successful > 0 {
+            StatusCode::PARTIAL_CONTENT
+        } else {
+            StatusCode::BAD_REQUEST
+        }
+    } else {
+        StatusCode::OK
+    };
+
+    Ok((status_code, Json(response)).into_response())
+}
+
 // Hander as a workarround for drag & drop (does not support POST requests)
 #[utoipa::path(
     get,

src/interfaces/api/routes.rs

@@ -237,6 +237,7 @@ pub fn create_api_routes(app_state: &Arc<AppState>) -> Router<Arc<AppState>> {
         .route("/folders/delete", post(batch_handler::delete_folders_batch))
         .route("/folders/create", post(batch_handler::create_folders_batch))
         .route("/folders/get", post(batch_handler::get_folders_batch))
+        .route("/folders/copy", post(batch_handler::copy_folders_batch))
         .route("/folders/move", post(batch_handler::move_folders_batch))
         // Trash operations (soft delete)
         .route("/trash", post(batch_handler::trash_batch))

static/js/features/files/fileOperations.js

@@ -928,23 +928,31 @@ const fileOps = {
 
     /**
      * Copy a folder to another folder
-     * Note: Backend folder copy is not yet implemented, this shows a notification
-     * @param {string} _folderId - Folder ID
-     * @param {string} _targetFolderId - Target folder ID
+     * @param {string} folderId - Folder ID
+     * @param {string} targetFolderId - Target folder ID
      * @returns {Promise<boolean>} - Success status
      */
-    async copyFolder(_folderId, _targetFolderId) {
-        // Folder copy is not yet implemented in the backend
-        ui.showNotification('Not implemented', 'Folder copy is not yet supported');
-        return false;
+    async copyFolder(folderId, targetFolderId) {
+        const res = await fetch('/api/batch/folders/copy', {
+            method: 'POST',
+            headers: { ...getAuthHeaders(), 'Content-Type': 'application/json' },
+            body: JSON.stringify({ folder_ids: [folderId], target_folder_id: targetFolderId })
+        });
+        return res.ok;
     },
 
+    /**
+     * @typedef {Object} BatchCopyReturn
+     * @property {number} success
+     * @property {number} errors
+     */
+
     /**
      * Copy files & folders
      * @param {string[]} fileIds - File IDs
      * @param {string[]} folderIds - Folder IDs
      * @param {string} targetFolderId - Target folder ID
-     * @returns {Promise<boolean>} - Success status
+     * @returns {Promise<BatchCopyReturn>} - Success status
      */
     async batchCopy(fileIds, folderIds, targetFolderId) {
         // FIXME ensure not moving a folder into itself
@@ -964,13 +972,22 @@ const fileOps = {
                 });
                 const data = await res.json();
                 success += data.stats?.successful || 0;
-                errors += data.stats?.failed || 0;
+                errors += data.stats?.failed || (!res.ok && !data.stats ? fileIds.length : 0);
             }
 
-            // Note: Folder copy is not yet implemented in batch API
+            // Batch copy folders
             if (folderIds.length > 0) {
-                ui.showNotification('Info', 'Folder copy is not yet supported in batch mode');
-                errors += folderIds.lenngth;
+                const res = await fetch('/api/batch/folders/copy', {
+                    method: 'POST',
+                    headers: { ...getAuthHeaders(), 'Content-Type': 'application/json' },
+                    body: JSON.stringify({
+                        folder_ids: folderIds,
+                        target_folder_id: targetFolderId
+                    })
+                });
+                const data = await res.json();
+                success += data.stats?.successful || 0;
+                errors += data.stats?.failed || (!res.ok && !data.stats ? folderIds.length : 0);
             }
         } catch (err) {
             console.error('Batch copy error:', err);