upload files to backend

6 files changed, 299 insertions, 4 deletions

diff --git a/backend/app/main.py b/backend/app/main.py
index 261b45a..886bd9e 100644
--- a/backend/app/main.py
+++ b/backend/app/main.py
@@ -1,6 +1,7 @@
 from fastapi import FastAPI, HTTPException
 from fastapi.middleware.cors import CORSMiddleware
 from fastapi.responses import StreamingResponse, FileResponse
+from fastapi import UploadFile, File
 from pydantic import BaseModel
 from app.schemas import NodeRunRequest, NodeRunResponse, MergeStrategy, Role, Message, Context, LLMConfig, ModelProvider, ReasoningEffort
 from app.services.llm import llm_streamer, generate_title
@@ -9,6 +10,7 @@ import os
 import json
 import shutil
 from typing import List, Literal, Optional
+from uuid import uuid4
 
 load_dotenv()
 
@@ -49,6 +51,12 @@ def archive_root(user: str) -> str:
     return os.path.join(ensure_user_root(user), "archive")
 
 
+def files_root(user: str) -> str:
+    root = os.path.join(ensure_user_root(user), "files")
+    os.makedirs(root, exist_ok=True)
+    return root
+
+
 def migrate_legacy_layout(user: str):
     """
     Migrate from legacy ./projects/<user> and legacy archive folders to the new data/<user>/ structure.
@@ -136,6 +144,15 @@ class RenameRequest(BaseModel):
     new_name: Optional[str] = None
     new_path: Optional[str] = None
 
+class FileMeta(BaseModel):
+    id: str
+    name: str
+    size: int
+    mime: str
+    created_at: float
+    provider: Optional[str] = None
+    provider_file_id: Optional[str] = None
+
 class FolderRequest(BaseModel):
     user: str = DEFAULT_USER
     path: str  # relative folder path
@@ -375,6 +392,27 @@ def archived_path(user: str) -> str:
     root = archive_root(user)
     return os.path.join(root, ARCHIVE_FILENAME)
 
+# ---------------- Files (uploads) ----------------
+def files_index_path(user: str) -> str:
+    return os.path.join(files_root(user), "index.json")
+
+
+def load_files_index(user: str) -> List[FileMeta]:
+    path = files_index_path(user)
+    if not os.path.exists(path):
+        return []
+    with open(path, "r", encoding="utf-8") as f:
+        data = json.load(f)
+    return [FileMeta(**item) for item in data]
+
+
+def save_files_index(user: str, items: List[FileMeta]):
+    path = files_index_path(user)
+    os.makedirs(os.path.dirname(path), exist_ok=True)
+    with open(path, "w", encoding="utf-8") as f:
+        json.dump([item.model_dump() for item in items], f, ensure_ascii=False, indent=2)
+
+# -------------------------------------------------
 
 @app.get("/api/projects/archived")
 def get_archived_nodes(user: str = DEFAULT_USER):
@@ -401,3 +439,65 @@ def save_archived_nodes(payload: dict):
         return {"ok": True}
     except Exception as e:
         raise HTTPException(status_code=500, detail=str(e))
+
+
+@app.get("/api/files")
+def list_files(user: str = DEFAULT_USER):
+    migrate_legacy_layout(user)
+    items = load_files_index(user)
+    return {"files": [item.model_dump() for item in items]}
+
+
+@app.post("/api/files/upload")
+async def upload_file(user: str = DEFAULT_USER, file: UploadFile = File(...)):
+    migrate_legacy_layout(user)
+    items = load_files_index(user)
+    file_id = str(uuid4())
+    dest_root = files_root(user)
+    dest_path = os.path.join(dest_root, file_id)
+    try:
+        content = await file.read()
+        size = len(content)
+        with open(dest_path, "wb") as f:
+            f.write(content)
+    except Exception as e:
+        raise HTTPException(status_code=500, detail=str(e))
+
+    meta = FileMeta(
+        id=file_id,
+        name=file.filename,
+        size=size,
+        mime=file.content_type or "application/octet-stream",
+        created_at=os.path.getmtime(dest_path),
+    )
+    items.append(meta)
+    save_files_index(user, items)
+    return {"file": meta}
+
+
+@app.get("/api/files/download")
+def download_file(user: str = DEFAULT_USER, file_id: str = ""):
+    migrate_legacy_layout(user)
+    items = load_files_index(user)
+    meta = next((i for i in items if i.id == file_id), None)
+    if not meta:
+        raise HTTPException(status_code=404, detail="file not found")
+    path = os.path.join(files_root(user), file_id)
+    if not os.path.exists(path):
+        raise HTTPException(status_code=404, detail="file missing on disk")
+    return FileResponse(path, filename=meta.name, media_type=meta.mime)
+
+
+@app.post("/api/files/delete")
+def delete_file(user: str = DEFAULT_USER, file_id: str = ""):
+    migrate_legacy_layout(user)
+    items = load_files_index(user)
+    meta = next((i for i in items if i.id == file_id), None)
+    if not meta:
+        raise HTTPException(status_code=404, detail="file not found")
+    path = os.path.join(files_root(user), file_id)
+    if os.path.exists(path):
+        os.remove(path)
+    items = [i for i in items if i.id != file_id]
+    save_files_index(user, items)
+    return {"ok": True}
diff --git a/backend/data/test/files/58252c05-718e-4eea-a23d-56a64d03b4fc b/backend/data/test/files/58252c05-718e-4eea-a23d-56a64d03b4fc
new file mode 100644
index 0000000..a837816
--- /dev/null
+++ b/backend/data/test/files/58252c05-718e-4eea-a23d-56a64d03b4fc
diff --git a/backend/data/test/files/index.json b/backend/data/test/files/index.json
new file mode 100644
index 0000000..d9e559f
--- /dev/null
+++ b/backend/data/test/files/index.json
@@ -0,0 +1,11 @@
+[
+  {
+    "id": "58252c05-718e-4eea-a23d-56a64d03b4fc",
+    "name": "survey_on_survey (3).pdf",
+    "size": 263914,
+    "mime": "application/pdf",
+    "created_at": 1765324835.7883003,
+    "provider": null,
+    "provider_file_id": null
+  }
+]
\ No newline at end of file
diff --git a/backend/requirements.txt b/backend/requirements.txt
index 545f6b7..e340864 100644
--- a/backend/requirements.txt
+++ b/backend/requirements.txt
@@ -5,4 +5,5 @@ openai
 google-generativeai
 python-dotenv
 httpx
+python-multipart
 
diff --git a/frontend/src/components/LeftSidebar.tsx b/frontend/src/components/LeftSidebar.tsx
index 1b7ccb2..a75df39 100644
--- a/frontend/src/components/LeftSidebar.tsx
+++ b/frontend/src/components/LeftSidebar.tsx
@@ -4,7 +4,7 @@ import {
   Folder, FileText, Archive, ChevronLeft, ChevronRight, Trash2, MessageSquare, 
   MoreVertical, Download, Upload, Plus, RefreshCw, Edit3 
 } from 'lucide-react';
-import useFlowStore, { type FSItem, type BlueprintDocument } from '../store/flowStore';
+import useFlowStore, { type FSItem, type BlueprintDocument, type FileMeta } from '../store/flowStore';
 
 interface LeftSidebarProps {
   isOpen: boolean;
@@ -18,11 +18,15 @@ const LeftSidebar: React.FC<LeftSidebarProps> = ({ isOpen, onToggle }) => {
     removeFromArchive,
     createNodeFromArchive,
     theme,
+    files,
     projectTree,
     currentBlueprintPath,
     saveStatus,
     refreshProjectTree,
     loadArchivedNodes,
+    refreshFiles,
+    uploadFile,
+    deleteFile,
     readBlueprintFile,
     loadBlueprint,
     saveBlueprintFile,
@@ -37,6 +41,7 @@ const LeftSidebar: React.FC<LeftSidebarProps> = ({ isOpen, onToggle }) => {
   const { setViewport, getViewport } = useReactFlow();
   const isDark = theme === 'dark';
   const fileInputRef = useRef<HTMLInputElement | null>(null);
+  const fileUploadRef = useRef<HTMLInputElement | null>(null);
   const [contextMenu, setContextMenu] = useState<{ x: number; y: number; item?: FSItem } | null>(null);
   const [currentFolder, setCurrentFolder] = useState<string>('.');
   const [dragItem, setDragItem] = useState<FSItem | null>(null);
@@ -93,6 +98,13 @@ const LeftSidebar: React.FC<LeftSidebarProps> = ({ isOpen, onToggle }) => {
     loadArchivedNodes().catch(() => {});
   }, [loadArchivedNodes]);
 
+  // Load files when entering files tab
+  useEffect(() => {
+    if (activeTab === 'files') {
+      refreshFiles().catch(() => {});
+    }
+  }, [activeTab, refreshFiles]);
+
   // Context menu handlers
   const openContextMenu = (e: React.MouseEvent, item?: FSItem) => {
     e.preventDefault();
@@ -217,6 +229,52 @@ const LeftSidebar: React.FC<LeftSidebarProps> = ({ isOpen, onToggle }) => {
     await refreshProjectTree();
   };
 
+  // Files tab handlers
+  const handleFilesUpload = async (list: FileList) => {
+    let ok = 0;
+    let failed: string[] = [];
+    for (const f of Array.from(list)) {
+      try {
+        await uploadFile(f);
+        ok += 1;
+      } catch (e) {
+        console.error(e);
+        failed.push(`${f.name}: ${(e as Error).message}`);
+      }
+    }
+    await refreshFiles();
+    if (failed.length) {
+      alert(`Some files failed:\n${failed.join('\n')}`);
+    } else if (ok > 0) {
+      // Optional: brief feedback
+      console.info(`Uploaded ${ok} file(s)`);
+    }
+  };
+
+  const handleFilesInputChange = async (e: React.ChangeEvent<HTMLInputElement>) => {
+    const files = e.target.files;
+    if (files && files.length > 0) {
+      await handleFilesUpload(files);
+      e.target.value = '';
+    }
+  };
+
+  const handleDownloadFile = (file: FileMeta) => {
+    const url = `${import.meta.env.VITE_BACKEND_URL || 'http://localhost:8000'}/api/files/download?user=test&file_id=${encodeURIComponent(file.id)}`;
+    const a = document.createElement('a');
+    a.href = url;
+    a.download = file.name;
+    a.click();
+  };
+
+  const formatSize = (bytes: number) => {
+    if (bytes === 0) return '0 B';
+    const k = 1024;
+    const sizes = ['B', 'KB', 'MB', 'GB', 'TB'];
+    const i = Math.floor(Math.log(bytes) / Math.log(k));
+    return `${(bytes / Math.pow(k, i)).toFixed(1)} ${sizes[i]}`;
+  };
+
   // Fade-out for "Saved" indicator
   useEffect(() => {
     if (saveStatus === 'saved') {
@@ -517,9 +575,79 @@ const LeftSidebar: React.FC<LeftSidebarProps> = ({ isOpen, onToggle }) => {
           </div>
         )}
         {activeTab === 'files' && (
-          <div className="flex flex-col items-center justify-center h-full opacity-50">
-            <FileText size={48} className="mb-2" />
-            <p>File manager coming soon</p>
+          <div 
+            className="flex flex-col h-full gap-2"
+            onDragOver={(e) => { if (e.dataTransfer.types.includes('Files')) e.preventDefault(); }}
+            onDrop={async (e) => {
+              if (e.dataTransfer.files?.length) {
+                e.preventDefault();
+                await handleFilesUpload(e.dataTransfer.files);
+              }
+            }}
+          >
+            <div className="flex items-center gap-2">
+              <button
+                onClick={() => refreshFiles()}
+                className={`p-1 rounded ${isDark ? 'hover:bg-gray-700' : 'hover:bg-gray-200'}`}
+                title="Refresh files"
+              >
+                <RefreshCw size={14} />
+              </button>
+              <button
+                onClick={() => fileUploadRef.current?.click()}
+                className={`p-1 rounded ${isDark ? 'hover:bg-gray-700' : 'hover:bg-gray-200'}`}
+                title="Upload files (drag & drop supported)"
+              >
+                <Upload size={14} />
+              </button>
+              <input
+                ref={fileUploadRef}
+                type="file"
+                multiple
+                className="hidden"
+                onChange={handleFilesInputChange}
+              />
+              <span className={`text-xs ${isDark ? 'text-gray-500' : 'text-gray-500'}`}>Drag files here or click upload</span>
+            </div>
+
+            {files.length === 0 ? (
+              <div className="flex flex-col items-center justify-center h-full opacity-50 border border-dashed border-gray-300 dark:border-gray-700 rounded">
+                <FileText size={32} className="mb-2" />
+                <p className="text-xs text-center">No files uploaded yet.</p>
+              </div>
+            ) : (
+              <div className="flex-1 overflow-y-auto space-y-1">
+                {files.map(f => (
+                  <div
+                    key={f.id}
+                    className={`flex items-center justify-between px-2 py-1 rounded border ${isDark ? 'border-gray-700 hover:bg-gray-800' : 'border-gray-200 hover:bg-gray-100'}`}
+                  >
+                    <div className="flex flex-col">
+                      <span className="text-sm font-medium">{f.name}</span>
+                      <span className={`text-[11px] ${isDark ? 'text-gray-500' : 'text-gray-500'}`}>
+                        {formatSize(f.size)} • {new Date(f.created_at * 1000).toLocaleString()}
+                      </span>
+                    </div>
+                    <div className="flex items-center gap-2">
+                      <button
+                        onClick={() => handleDownloadFile(f)}
+                        className={`p-1 rounded ${isDark ? 'hover:bg-gray-700' : 'hover:bg-gray-200'}`}
+                        title="Download"
+                      >
+                        <Download size={14} />
+                      </button>
+                      <button
+                        onClick={async () => { if (confirm('Delete this file?')) { await deleteFile(f.id); } }}
+                        className={`p-1 rounded ${isDark ? 'hover:bg-red-900 text-red-300' : 'hover:bg-red-50 text-red-600'}`}
+                        title="Delete"
+                      >
+                        <Trash2 size={14} />
+                      </button>
+                    </div>
+                  </div>
+                ))}
+              </div>
+            )}
           </div>
         )}
         {activeTab === 'archive' && (
diff --git a/frontend/src/store/flowStore.ts b/frontend/src/store/flowStore.ts
index 56ade75..a049a8a 100644
--- a/frontend/src/store/flowStore.ts
+++ b/frontend/src/store/flowStore.ts
@@ -121,11 +121,22 @@ export interface ArchivedNode {
   mergeStrategy?: 'raw' | 'smart';
 }
 
+export interface FileMeta {
+  id: string;
+  name: string;
+  size: number;
+  mime: string;
+  created_at: number;
+  provider?: string;
+  provider_file_id?: string;
+}
+
 interface FlowState {
   nodes: LLMNode[];
   edges: Edge[];
   selectedNodeId: string | null;
   archivedNodes: ArchivedNode[];  // Stored node templates
+  files: FileMeta[];
   theme: 'light' | 'dark';
   projectTree: FSItem[];
   currentBlueprintPath?: string;
@@ -188,6 +199,10 @@ interface FlowState {
   clearBlueprint: () => void;
   loadArchivedNodes: () => Promise<void>;
   saveArchivedNodes: () => Promise<void>;
+  refreshFiles: () => Promise<void>;
+  uploadFile: (file: File) => Promise<FileMeta>;
+  deleteFile: (fileId: string) => Promise<void>;
+  setFiles: (files: FileMeta[]) => void;
 
   // Merge trace functions
   createMergedTrace: (
@@ -247,6 +262,7 @@ const useFlowStore = create<FlowState>((set, get) => {
   edges: [],
   selectedNodeId: null,
   archivedNodes: [],
+  files: [],
   theme: 'light' as const,
   projectTree: [],
   currentBlueprintPath: undefined,
@@ -268,6 +284,9 @@ const useFlowStore = create<FlowState>((set, get) => {
     set({ lastViewport: viewport });
   },
 
+  setFiles: (files: FileMeta[]) => {
+    set({ files });
+  },
   findNonOverlappingPosition: (baseX: number, baseY: number) => {
     const { nodes } = get();
     // Estimate larger dimensions to be safe, considering dynamic handles
@@ -1529,6 +1548,42 @@ const useFlowStore = create<FlowState>((set, get) => {
     });
   },
 
+  // Files management
+  refreshFiles: async () => {
+    const res = await jsonFetch<{ files: FileMeta[] }>(
+      `${API_BASE}/api/files?user=${encodeURIComponent(DEFAULT_USER)}`
+    );
+    set({ files: res.files || [] });
+  },
+
+  uploadFile: async (file: File) => {
+    const form = new FormData();
+    form.append('file', file);
+    const res = await fetch(`${API_BASE}/api/files/upload?user=${encodeURIComponent(DEFAULT_USER)}`, {
+      method: 'POST',
+      body: form,
+    });
+    if (!res.ok) {
+      throw new Error(await res.text());
+    }
+    const data = await res.json();
+    if (!data.file) {
+      throw new Error('Upload succeeded but no file info returned');
+    }
+    await get().refreshFiles();
+    return data.file as FileMeta;
+  },
+
+  deleteFile: async (fileId: string) => {
+    const res = await fetch(`${API_BASE}/api/files/delete?user=${encodeURIComponent(DEFAULT_USER)}&file_id=${encodeURIComponent(fileId)}`, {
+      method: 'POST',
+    });
+    if (!res.ok) {
+      throw new Error(await res.text());
+    }
+    await get().refreshFiles();
+  },
+
   // --------------------------------------------------------
 
   // Compute merged messages based on strategy