Merge pull request #108 from SatyamPrakash09/feat/chat-export

backend/app/routes/chat.py

@@ -166,6 +166,79 @@ def get_chat_history(
     return ChatHistoryResponse(messages=formatted, document_id=document_id)
 
 
+@router.get("/export/{document_id}")
+def export_chat_history(
+    document_id: str,
+    format: str = "md",
+    token: Optional[str] = None,
+    db: Session = Depends(get_db),
+):
+    """Export chat history for a document as a downloadable .md or .txt file.
+    
+    Accepts auth via either:
+    - Authorization: Bearer <token> header (standard)
+    - ?token=<jwt> query parameter (for browser downloads)
+    """
+    from fastapi import Request
+    from app.auth import decode_token as _decode
+
+    # Resolve user from query-param token (browser download links can't set headers)
+    resolved_user = None
+    if token:
+        user_id = _decode(token)
+        if user_id:
+            resolved_user = db.query(User).filter(User.id == user_id).first()
+    
+    if resolved_user is None:
+        raise HTTPException(status_code=401, detail="Authentication required")
+
+    if format not in ("md", "txt"):
+        raise HTTPException(status_code=400, detail="Format must be 'md' or 'txt'")
+
+    # Verify document exists and belongs to user
+    doc = db.query(Document).filter(
+        Document.id == document_id,
+        Document.user_id == resolved_user.id,
+    ).first()
+
+    if not doc:
+        raise HTTPException(status_code=404, detail="Document not found")
+
+    messages = (
+        db.query(ChatMessage)
+        .filter(
+            ChatMessage.user_id == resolved_user.id,
+            ChatMessage.document_id == document_id,
+        )
+        .order_by(ChatMessage.created_at.asc())
+        .all()
+    )
+
+    if not messages:
+        raise HTTPException(status_code=404, detail="No chat history found for this document")
+
+    if format == "md":
+        content = _format_markdown(doc, messages)
+        media_type = "text/markdown"
+        extension = "md"
+    else:
+        content = _format_plaintext(doc, messages)
+        media_type = "text/plain"
+        extension = "txt"
+
+    safe_name = doc.original_name.rsplit(".", 1)[0]
+    filename = f"{safe_name}_chat_history.{extension}"
+
+    from fastapi.responses import Response
+    return Response(
+        content=content,
+        media_type=media_type,
+        headers={
+            "Content-Disposition": f'attachment; filename="{filename}"',
+        },
+    )
+
+
 @router.delete("/history/{document_id}")
 def clear_chat_history(
     document_id: str,
@@ -200,3 +273,89 @@ def _save_message(
     )
     db.add(msg)
     db.commit()
+
+
+def _format_markdown(doc, messages) -> str:
+    """Format chat history as a Markdown document."""
+    lines = [
+        f"# Chat History — {doc.original_name}",
+        "",
+        f"**Document:** {doc.original_name}  ",
+        f"**Exported at:** {__import__('datetime').datetime.now().strftime('%Y-%m-%d %H:%M:%S')}  ",
+        f"**Total messages:** {len(messages)}",
+        "",
+        "---",
+        "",
+    ]
+
+    for msg in messages:
+        timestamp = msg.created_at.strftime("%Y-%m-%d %H:%M:%S") if msg.created_at else ""
+        role_label = "**You**" if msg.role == "user" else "**Assistant**"
+
+        lines.append(f"### {role_label}")
+        lines.append(f"*{timestamp}*")
+        lines.append("")
+        lines.append(msg.content)
+        lines.append("")
+
+        # Include source citations for assistant messages
+        if msg.role == "assistant" and msg.sources_json:
+            try:
+                sources = json.loads(msg.sources_json)
+                if sources:
+                    lines.append("**Sources:**")
+                    lines.append("")
+                    for i, src in enumerate(sources, 1):
+                        lines.append(f"> **[{i}]** {src.get('filename', 'Unknown')}, "
+                                     f"Page {src.get('page', '?')} "
+                                     f"(Confidence: {src.get('confidence', 0)}%)")
+                        text_preview = src.get("text", "")[:150]
+                        if text_preview:
+                            lines.append(f"> {text_preview}...")
+                        lines.append(">")
+                    lines.append("")
+            except Exception:
+                pass
+
+        lines.append("---")
+        lines.append("")
+
+    return "\n".join(lines)
+
+
+def _format_plaintext(doc, messages) -> str:
+    """Format chat history as plain text."""
+    lines = [
+        f"Chat History — {doc.original_name}",
+        f"Exported at: {__import__('datetime').datetime.now().strftime('%Y-%m-%d %H:%M:%S')}",
+        f"Total messages: {len(messages)}",
+        "=" * 60,
+        "",
+    ]
+
+    for msg in messages:
+        timestamp = msg.created_at.strftime("%Y-%m-%d %H:%M:%S") if msg.created_at else ""
+        role_label = "You" if msg.role == "user" else "Assistant"
+
+        lines.append(f"[{role_label}] ({timestamp})")
+        lines.append(msg.content)
+
+        # Include source citations for assistant messages
+        if msg.role == "assistant" and msg.sources_json:
+            try:
+                sources = json.loads(msg.sources_json)
+                if sources:
+                    lines.append("")
+                    lines.append("Sources:")
+                    for i, src in enumerate(sources, 1):
+                        lines.append(f"  [{i}] {src.get('filename', 'Unknown')}, "
+                                     f"Page {src.get('page', '?')} "
+                                     f"(Confidence: {src.get('confidence', 0)}%)")
+            except Exception:
+                pass
+
+        lines.append("-" * 60)
+        lines.append("")
+
+    return "\n".join(lines)
+

frontend/src/app/dashboard/page.tsx

@@ -39,8 +39,10 @@ export default function DashboardPage() {
   // Load documents
   const loadDocuments = useCallback(async () => {
     try {
-      const data = await api.get<{ documents: DocInfo[] }>("/api/v1/documents/");
-      setDocuments(data.documents);
+      const data = await api.get<{ documents?: DocInfo[]; items?: DocInfo[] }>(
+        "/api/v1/documents/"
+      );
+      setDocuments(data?.documents ?? data?.items ?? []);
       setConnectionError("");
     } catch (err) {
       const message = err instanceof Error ? err.message : CONNECTION_ERROR_MESSAGE;
@@ -62,7 +64,7 @@ export default function DashboardPage() {
 
   // Poll for processing status
   useEffect(() => {
-    const hasPending = documents.some(
+    const hasPending = (documents || []).some(
       (d) => d.status === "pending" || d.status === "processing"
     );
     if (!hasPending) return;

frontend/src/components/chat/ChatPanel.tsx

@@ -2,12 +2,12 @@
 
 import { useState, useRef, useEffect } from "react";
 import type { DocInfo } from "@/app/dashboard/page";
-import { api } from "@/lib/api";
+import { api, API_BASE } from "@/lib/api";
 import { Button } from "@/components/ui/button";
 import { Textarea } from "@/components/ui/textarea";
 import MessageBubble from "./MessageBubble";
 import SourceCard from "./SourceCard";
-import { Send, Loader2, Trash2, MessageSquare } from "lucide-react";
+import { Send, Loader2, Trash2, MessageSquare, Download } from "lucide-react";
 
 export interface SourceChunk {
   text: string;
@@ -35,9 +35,11 @@ export default function ChatPanel({ activeDoc, onCitationClick }: Props) {
   const [input, setInput] = useState("");
   const [streaming, setStreaming] = useState(false);
   const [isTyping, setIsTyping] = useState(false);
+  const [showExportMenu, setShowExportMenu] = useState(false);
   const textareaRef = useRef<HTMLTextAreaElement>(null);
   const bottomRef = useRef<HTMLDivElement>(null);
   const prevDocId = useRef<string | null>(null);
+  const exportMenuRef = useRef<HTMLDivElement>(null);
 
   useEffect(() => {
     const textarea = textareaRef.current;
@@ -209,6 +211,32 @@ export default function ChatPanel({ activeDoc, onCitationClick }: Props) {
     }
   };
 
+  const handleExport = (format: "md" | "txt") => {
+    if (!activeDoc) return;
+    setShowExportMenu(false);
+    const token = localStorage.getItem("token");
+    const url = `${API_BASE}/api/v1/chat/export/${activeDoc.id}?format=${format}&token=${token}`;
+    // Trigger download via a temporary anchor
+    const a = document.createElement("a");
+    a.href = url;
+    a.download = "";
+    document.body.appendChild(a);
+    a.click();
+    document.body.removeChild(a);
+  };
+
+  // Close export dropdown on outside click
+  useEffect(() => {
+    if (!showExportMenu) return;
+    const handleClickOutside = (e: MouseEvent) => {
+      if (exportMenuRef.current && !exportMenuRef.current.contains(e.target as Node)) {
+        setShowExportMenu(false);
+      }
+    };
+    document.addEventListener("mousedown", handleClickOutside);
+    return () => document.removeEventListener("mousedown", handleClickOutside);
+  }, [showExportMenu]);
+
   const handleKeyDown = (e: React.KeyboardEvent) => {
     if (e.key === "Enter" && !e.shiftKey) {
       e.preventDefault();
@@ -291,14 +319,50 @@ export default function ChatPanel({ activeDoc, onCitationClick }: Props) {
               )}
             </Button>
             {messages.length > 0 && (
-              <Button
-                variant="ghost"
-                size="icon"
-                onClick={handleClear}
-                className="h-[44px] w-[44px] text-muted-foreground hover:text-destructive"
-              >
-                <Trash2 className="w-4 h-4" />
-              </Button>
+              <>
+                {/* Export dropdown */}
+                <div className="relative" ref={exportMenuRef}>
+                  <Button
+                    id="export-chat-btn"
+                    variant="ghost"
+                    size="icon"
+                    onClick={() => setShowExportMenu((v) => !v)}
+                    className="h-[44px] w-[44px] text-muted-foreground hover:text-primary"
+                    title="Export chat history"
+                  >
+                    <Download className="w-4 h-4" />
+                  </Button>
+                  {showExportMenu && (
+                    <div className="absolute bottom-full mb-2 right-0 min-w-[160px] rounded-lg border border-border bg-popover p-1 shadow-lg animate-in fade-in slide-in-from-bottom-2 z-50">
+                      <button
+                        id="export-md-btn"
+                        onClick={() => handleExport("md")}
+                        className="w-full flex items-center gap-2 rounded-md px-3 py-2 text-sm hover:bg-accent transition-colors text-left"
+                      >
+                        <span className="text-base">📝</span>
+                        Markdown (.md)
+                      </button>
+                      <button
+                        id="export-txt-btn"
+                        onClick={() => handleExport("txt")}
+                        className="w-full flex items-center gap-2 rounded-md px-3 py-2 text-sm hover:bg-accent transition-colors text-left"
+                      >
+                        <span className="text-base">📄</span>
+                        Plain Text (.txt)
+                      </button>
+                    </div>
+                  )}
+                </div>
+                {/* Clear history */}
+                <Button
+                  variant="ghost"
+                  size="icon"
+                  onClick={handleClear}
+                  className="h-[44px] w-[44px] text-muted-foreground hover:text-destructive"
+                >
+                  <Trash2 className="w-4 h-4" />
+                </Button>
+              </>
             )}
           </div>
         </div>

frontend/src/components/chat/SourceCard.tsx

@@ -11,7 +11,7 @@ interface Props {
   onPageClick: (page: number) => void;
 }
 
-export default function SourceCard({ sources, onPageClick }: Props) {
+export default function SourceCard({ sources = [], onPageClick }: Props) {
   const [expanded, setExpanded] = useState(false);
 
   if (sources.length === 0) return null;

frontend/src/components/document/DocumentSidebar.tsx

@@ -19,7 +19,7 @@ interface Props {
   onDocumentsChange: () => void;
 }
 
-export default function DocumentSidebar({ documents, activeDoc, onSelectDoc, onDocumentsChange }: Props) {
+export default function DocumentSidebar({ documents = [], activeDoc, onSelectDoc, onDocumentsChange }: Props) {
   const [uploading, setUploading] = useState(false);
   const [uploadProgress, setUploadProgress] = useState(0);
   const [uploadError, setUploadError] = useState("");

frontend/src/lib/api.ts

@@ -1,6 +1,7 @@
 /**
  * API client for the FastAPI backend.
- * Handles authentication headers and base URL configuration.
+ * Handles authentication headers, base URL configuration,
+ * and automatic token refresh on 401 responses.
  */
 
 const API_BASE = process.env.NEXT_PUBLIC_API_URL || "";
@@ -9,10 +10,14 @@ const CONNECTION_ERROR_BANNER_MESSAGE = `⚠️ ${CONNECTION_ERROR_MESSAGE}`;
 
 interface FetchOptions extends RequestInit {
   token?: string;
+  /** Skip auto-refresh for this request (used internally for the refresh call itself) */
+  _skipRefresh?: boolean;
 }
 
 class ApiClient {
   private baseUrl: string;
+  /** Guards against multiple concurrent refresh attempts */
+  private refreshPromise: Promise<string | null> | null = null;
 
   constructor(baseUrl: string) {
     this.baseUrl = baseUrl;
@@ -23,6 +28,11 @@ class ApiClient {
     return localStorage.getItem("token");
   }
 
+  private getRefreshToken(): string | null {
+    if (typeof window === "undefined") return null;
+    return localStorage.getItem("refresh_token");
+  }
+
   private getHeaders(token?: string): HeadersInit {
     const headers: HeadersInit = {
       "Content-Type": "application/json",
@@ -47,6 +57,67 @@ class ApiClient {
     }
   }
 
+  /**
+   * Attempt to refresh the access token using the stored refresh token.
+   * Uses a mutex so only one refresh happens at a time — concurrent
+   * 401s all wait on the same promise.
+   */
+  private async tryRefreshToken(): Promise<string | null> {
+    // If a refresh is already in-flight, wait for it
+    if (this.refreshPromise) {
+      return this.refreshPromise;
+    }
+
+    const refreshToken = this.getRefreshToken();
+    if (!refreshToken) return null;
+
+    this.refreshPromise = (async () => {
+      try {
+        const res = await this.fetchWithConnectionError(`${this.baseUrl}/api/v1/auth/refresh`, {
+          method: "POST",
+          headers: { "Content-Type": "application/json" },
+          body: JSON.stringify({ refresh_token: refreshToken }),
+        });
+
+        if (!res.ok) {
+          // Refresh token is also expired/invalid — force logout
+          this.clearTokens();
+          return null;
+        }
+
+        const data = await res.json();
+        // Store the new tokens
+        localStorage.setItem("token", data.access_token);
+        if (data.refresh_token) {
+          localStorage.setItem("refresh_token", data.refresh_token);
+        }
+
+        // Dispatch a custom event so AuthProvider can update its state
+        window.dispatchEvent(
+          new CustomEvent("auth:tokens-refreshed", {
+            detail: { accessToken: data.access_token, refreshToken: data.refresh_token, user: data.user },
+          })
+        );
+
+        return data.access_token as string;
+      } catch {
+        this.clearTokens();
+        return null;
+      } finally {
+        this.refreshPromise = null;
+      }
+    })();
+
+    return this.refreshPromise;
+  }
+
+  private clearTokens(): void {
+    localStorage.removeItem("token");
+    localStorage.removeItem("refresh_token");
+    // Notify AuthProvider to update state
+    window.dispatchEvent(new CustomEvent("auth:logged-out"));
+  }
+
   private getPayloadMessage(payload: unknown): string | null {
     if (typeof payload === "string" && payload.trim()) {
       return payload;
@@ -92,6 +163,14 @@ class ApiClient {
       ...options,
     });
 
+    // Auto-refresh on 401
+    if (res.status === 401 && !options?._skipRefresh) {
+      const newToken = await this.tryRefreshToken();
+      if (newToken) {
+        return this.get<T>(path, { ...options, token: newToken, _skipRefresh: true });
+      }
+    }
+
     if (!res.ok) {
       throw new Error(await this.getErrorMessage(res, res.statusText || "Request failed"));
     }
@@ -107,6 +186,14 @@ class ApiClient {
       ...options,
     });
 
+    // Auto-refresh on 401
+    if (res.status === 401 && !options?._skipRefresh) {
+      const newToken = await this.tryRefreshToken();
+      if (newToken) {
+        return this.post<T>(path, body, { ...options, token: newToken, _skipRefresh: true });
+      }
+    }
+
     if (!res.ok) {
       throw new Error(await this.getErrorMessage(res, res.statusText || "Request failed"));
     }
@@ -129,6 +216,14 @@ class ApiClient {
       ...options,
     });
 
+    // Auto-refresh on 401
+    if (res.status === 401 && !options?._skipRefresh) {
+      const newToken = await this.tryRefreshToken();
+      if (newToken) {
+        return this.postForm<T>(path, formData, { ...options, token: newToken, _skipRefresh: true });
+      }
+    }
+
     if (!res.ok) {
       throw new Error(await this.getErrorMessage(res, res.statusText || "Upload failed"));
     }
@@ -143,6 +238,14 @@ class ApiClient {
       ...options,
     });
 
+    // Auto-refresh on 401
+    if (res.status === 401 && !options?._skipRefresh) {
+      const newToken = await this.tryRefreshToken();
+      if (newToken) {
+        return this.delete<T>(path, { ...options, token: newToken, _skipRefresh: true });
+      }
+    }
+
     if (!res.ok) {
       throw new Error(await this.getErrorMessage(res, res.statusText || "Delete failed"));
     }
@@ -155,12 +258,24 @@ class ApiClient {
    * Yields parsed SSE data objects.
    */
   async *streamPost(path: string, body: unknown): AsyncGenerator<{ type: string; data?: unknown }> {
-    const res = await this.fetchWithConnectionError(`${this.baseUrl}${path}`, {
+    let res = await this.fetchWithConnectionError(`${this.baseUrl}${path}`, {
       method: "POST",
       headers: this.getHeaders(),
       body: JSON.stringify(body),
     });
 
+    // Auto-refresh on 401
+    if (res.status === 401) {
+      const newToken = await this.tryRefreshToken();
+      if (newToken) {
+        res = await this.fetchWithConnectionError(`${this.baseUrl}${path}`, {
+          method: "POST",
+          headers: this.getHeaders(newToken),
+          body: JSON.stringify(body),
+        });
+      }
+    }
+
     if (!res.ok) {
       throw new Error(await this.getErrorMessage(res, res.statusText || "Stream request failed"));
     }

frontend/src/lib/auth.tsx

@@ -44,34 +44,66 @@ export function AuthProvider({ children }: { children: React.ReactNode }) {
       .then(setUser)
       .catch(() => {
         localStorage.removeItem("token");
+        localStorage.removeItem("refresh_token");
         setToken(null);
       })
       .finally(() => setLoading(false));
   // eslint-disable-next-line react-hooks/exhaustive-deps
   }, []); // intentionally runs once on mount only
 
+  // ── Listen for token refresh events from ApiClient ──
+  // When the API client auto-refreshes tokens, it dispatches custom events
+  // so this context stays in sync without prop drilling.
+  useEffect(() => {
+    const handleTokensRefreshed = (e: Event) => {
+      const detail = (e as CustomEvent).detail;
+      if (detail?.accessToken) {
+        setToken(detail.accessToken);
+      }
+      if (detail?.user) {
+        setUser(detail.user);
+      }
+    };
+
+    const handleLoggedOut = () => {
+      setToken(null);
+      setUser(null);
+    };
+
+    window.addEventListener("auth:tokens-refreshed", handleTokensRefreshed);
+    window.addEventListener("auth:logged-out", handleLoggedOut);
+
+    return () => {
+      window.removeEventListener("auth:tokens-refreshed", handleTokensRefreshed);
+      window.removeEventListener("auth:logged-out", handleLoggedOut);
+    };
+  }, []);
+
   const login = useCallback(async (email: string, password: string) => {
-    const data = await api.post<{ access_token: string; user: User }>(
+    const data = await api.post<{ access_token: string; refresh_token: string; user: User }>(
       "/api/v1/auth/login",
       { email, password }
     );
     localStorage.setItem("token", data.access_token);
+    localStorage.setItem("refresh_token", data.refresh_token);
     setToken(data.access_token);
     setUser(data.user);
   }, []);
 
   const register = useCallback(async (username: string, email: string, password: string) => {
-    const data = await api.post<{ access_token: string; user: User }>(
+    const data = await api.post<{ access_token: string; refresh_token: string; user: User }>(
       "/api/v1/auth/register",
       { username, email, password }
     );
     localStorage.setItem("token", data.access_token);
+    localStorage.setItem("refresh_token", data.refresh_token);
     setToken(data.access_token);
     setUser(data.user);
   }, []);
 
   const logout = useCallback(() => {
     localStorage.removeItem("token");
+    localStorage.removeItem("refresh_token");
     setToken(null);
     setUser(null);
   }, []);