Update app.py

app.py

@@ -13,187 +13,124 @@ import torch
 # ---------------- CONFIGURATION ----------------
 logging.basicConfig(level=logging.INFO)
 
-# Load API key from Hugging Face secrets (or env)
+# Load API key from Hugging Face secrets
 GROQ_API_KEY = st.secrets.get("GROQ_API_KEY", os.environ.get("GROQ_API_KEY"))
 GROQ_MODEL = "llama-3.1-8b-instant"
 
-# Initialize Groq client silently (no top green message)
+# Initialize Groq client
 client = None
 if GROQ_API_KEY:
     try:
         client = Groq(api_key=GROQ_API_KEY)
-        logging.info("Groq client initialized (silent).")
+        # ✅ Removed the st.success message (Problem #1)
+        logging.info("✅ Groq client initialized successfully.")
     except Exception as e:
-        logging.exception("Groq init failed.")
+        st.error(f"❌ Failed to initialize Groq client: {e}")
         client = None
 else:
-    # Keep a visible but non-green hint if key is missing
     st.warning("⚠️ GROQ_API_KEY not found. Please add it to Hugging Face secrets.")
 
 # ---------------- STREAMLIT UI SETUP ----------------
 st.set_page_config(page_title="PDF Assistant", page_icon="📘", layout="wide")
 
-# ---------------- CSS (layout + styling) ----------------
-st.markdown(
-    """
+# ---------------- CSS ----------------
+st.markdown("""
 <style>
-:root{
-    --primary:#1e3a8a;
-    --bg:#0e1117;
-    --bg2:#1a1d29;
-    --text:#f0f2f6;
-}
-
-/* Fixed sidebar */
-section[data-testid="stSidebar"] {
+/* -------------------------------------- */
+/* 1. SCROLL FIX FOR SIDEBAR & MAIN AREA  */
+/* -------------------------------------- */
+/* Fix the sidebar and prevent it from scrolling */
+[data-testid="stSidebar"] {
     position: fixed;
+    overflow-y: hidden !important;
     height: 100vh;
-    overflow-y: auto;
-    padding-top: 0.5rem;
-    width: 300px;
+    z-index: 99;
 }
 
-/* Main content offset to the right of sidebar */
-.main {
-    margin-left: 320px;
-    padding-top: 16px;
+/* Allow the main content area to scroll independently */
+.main .block-container {
+    overflow-y: auto;
+    height: 100vh;
+    padding-bottom: 5rem; /* Space for scrolling */
 }
 
-/* Header (title + creator) */
-.header-left {
-    display: flex;
-    flex-direction: column;
-    align-items: flex-start;
-    gap: 4px;
-    margin-left: 8px;
+/* Hide main page scrollbar for cleaner look */
+::-webkit-scrollbar {
+    width: 8px;
 }
-.header-title {
-    font-size: 1.6rem;
-    font-weight: 600;
-    margin: 0;
+::-webkit-scrollbar-track {
+    background: #0e1117;
 }
-.header-creator {
-    font-size: 0.9rem;
-    color: var(--text);
+::-webkit-scrollbar-thumb {
+    background: #2d3748;
+    border-radius: 4px;
 }
 
-/* Chat scroll area */
-.chat-area {
-    height: calc(100vh - 200px);
-    overflow-y: auto;
-    padding: 1rem 2rem;
+/* -------------------------------------- */
+/* 2. CHAT & UI STYLING                   */
+/* -------------------------------------- */
+:root {
+    --primary-color: #1e3a8a;
+    --background-color: #0e1117;
+    --secondary-background-color: #1a1d29;
+    --text-color: #f0f2f6;
 }
 
-/* Chat bubble styles */
 .chat-user {
     background: #2d3748;
-    padding: 12px 14px;
-    border-radius: 18px 18px 4px 18px;
-    margin: 12px 0 12px auto;
-    max-width: 75%;
-    color: var(--text);
-    line-height: 1.4;
-    word-break: break-word;
+    padding: 12px;
+    border-radius: 10px 10px 2px 10px;
+    margin: 6px 0 6px auto;
+    max-width: 85%;
+    text-align: right;
+    color: var(--text-color);
 }
 .chat-bot {
-    background: var(--primary);
-    padding: 12px 14px;
-    border-radius: 18px 18px 18px 4px;
-    margin: 12px auto 12px 0;
-    max-width: 75%;
-    color: white;
-    line-height: 1.4;
-    word-break: break-word;
-}
-.sources {
-    font-size: 0.8rem;
-    opacity: 0.75;
-    margin-top: 8px;
-    border-top: 1px solid rgba(255,255,255,0.08);
-    padding-top: 6px;
+    background: var(--primary-color);
+    padding: 12px;
+    border-radius: 10px 10px 10px 2px;
+    margin: 6px auto 6px 0;
+    max-width: 85%;
+    text-align: left;
+    color: #ffffff;
 }
 
-/* Sticky input bar at bottom of main area */
-.input-bar {
-    position: sticky;
-    bottom: 0;
-    left: 320px;
-    right: 0;
-    background: var(--bg);
-    padding: 12px 20px;
-    border-top: 1px solid rgba(255,255,255,0.06);
-    z-index: 999;
+.sources {
+    font-size: 0.8em;
+    opacity: 0.7;
+    margin-top: 10px;
+    border-top: 1px solid rgba(255, 255, 255, 0.1);
+    padding-top: 5px;
 }
 
-/* Form layout */
-.input-row {
-    max-width: 980px;
-    margin: 0 auto;
-    display: flex;
-    gap: 8px;
-    align-items: center;
-}
-.text-input {
-    flex: 1;
-    background: transparent;
-    border: 1px solid rgba(255,255,255,0.06);
-    padding: 10px 14px;
-    border-radius: 999px;
-    color: var(--text);
-    outline: none;
-    font-size: 1rem;
-}
-.text-input::placeholder {
-    color: rgba(255,255,255,0.45);
-}
-.submit-arrow {
-    background: var(--primary);
-    color: white;
+/* -------------------------------------- */
+/* 3. INPUT FORM STYLING                  */
+/* -------------------------------------- */
+/* Align the input box and button properly */
+[data-testid="stForm"] {
     border: none;
-    height: 42px;
-    width: 42px;
-    border-radius: 50%;
-    display: inline-flex;
-    align-items: center;
-    justify-content: center;
-    font-weight: 700;
-    cursor: pointer;
-}
-.submit-arrow:disabled {
-    opacity: 0.45;
-    cursor: not-allowed;
-}
-
-/* Small responsive tweak */
-@media (max-width: 768px) {
-    section[data-testid="stSidebar"] {
-        position: relative;
-        width: 100%;
-        height: auto;
-    }
-    .main {
-        margin-left: 0;
-    }
-    .input-bar { left: 0; }
+    padding: 0;
 }
 </style>
-""",
-    unsafe_allow_html=True,
-)
+""", unsafe_allow_html=True)
 
 # ---------------- SESSION STATE ----------------
 if "chat" not in st.session_state:
     st.session_state.chat = []
+
 if "vectorstore" not in st.session_state:
     st.session_state.vectorstore = None
+
 if "retriever" not in st.session_state:
     st.session_state.retriever = None
+
 if "uploaded_file_name" not in st.session_state:
     st.session_state.uploaded_file_name = None
+
 if "uploader_key" not in st.session_state:
     st.session_state.uploader_key = 0
 
-# ---------------- HELPERS / LOGIC ----------------
+# ---------------- FUNCTIONS ----------------
 def clear_chat_history():
     st.session_state.chat = []
 
@@ -208,47 +145,54 @@ def clear_memory():
     st.success("Memory cleared. Please upload a new PDF.")
 
 def process_pdf(uploaded_file):
+    """Process uploaded PDF and create vectorstore."""
     try:
         with tempfile.NamedTemporaryFile(delete=False, suffix=".pdf") as tmp:
             tmp.write(uploaded_file.getvalue())
             path = tmp.name
-
+        
         loader = PyPDFLoader(path)
         docs = loader.load()
-
-        splitter = RecursiveCharacterTextSplitter(chunk_size=800, chunk_overlap=50)
+        
+        splitter = RecursiveCharacterTextSplitter(
+            chunk_size=800,
+            chunk_overlap=50
+        )
         chunks = splitter.split_documents(docs)
-
+        
         embeddings = HuggingFaceEmbeddings(
             model_name="sentence-transformers/all-MiniLM-L6-v2",
             model_kwargs={"device": "cpu"},
-            encode_kwargs={"normalize_embeddings": True},
+            encode_kwargs={"normalize_embeddings": True}
         )
-
+        
         vectorstore = Chroma.from_documents(chunks, embeddings)
         retriever = vectorstore.as_retriever(search_kwargs={"k": 3})
-
+        
         st.session_state.vectorstore = vectorstore
         st.session_state.retriever = retriever
-
+        
         if os.path.exists(path):
             os.unlink(path)
-
+        
         return len(chunks)
+        
     except Exception as e:
-        logging.exception("PDF processing error")
-        st.error(f"Error processing PDF: {e}")
+        st.error(f"Error processing PDF: {str(e)}")
         return None
 
 def ask_question(question):
+    """Retrieve and generate answer for the question."""
     if not client:
         return None, 0, "Groq client is not initialized. Check API key setup."
+    
     if not st.session_state.retriever:
         return None, 0, "Upload PDF first to initialize the knowledge base."
+    
     try:
         docs = st.session_state.retriever.invoke(question)
         context = "\n\n".join(d.page_content for d in docs)
-
+        
         prompt = f"""
 You are a strict RAG Q&A assistant.
 Use ONLY the context provided. If the answer is not found, reply:
@@ -265,108 +209,119 @@ FINAL ANSWER:
         response = client.chat.completions.create(
             model=GROQ_MODEL,
             messages=[
-                {"role": "system", "content": "Use only the PDF content. If answer not found, say: 'I cannot find this in the PDF.'"},
-                {"role": "user", "content": prompt},
+                {"role": "system",
+                 "content": "Use only the PDF content. If answer not found, say: 'I cannot find this in the PDF.'"},
+                {"role": "user", "content": prompt}
             ],
-            temperature=0.0,
+            temperature=0.0
         )
+        
         answer = response.choices[0].message.content.strip()
         return answer, len(docs), None
+        
     except APIError as e:
         return None, 0, f"Groq API Error: {str(e)}"
     except Exception as e:
-        logging.exception("Ask error")
         return None, 0, f"General error: {str(e)}"
 
-# ---------------- SIDEBAR (Upload + Controls) ----------------
-with st.sidebar:
-    st.markdown("### Upload PDF", unsafe_allow_html=True)
-    uploaded = st.file_uploader("Choose a PDF file", type=["pdf"], key=st.session_state.uploader_key, label_visibility="collapsed")
-    if uploaded and uploaded.name != st.session_state.uploaded_file_name:
-        # reset chat and process
-        st.session_state.chat = []
-        st.session_state.uploaded_file_name = None
-        with st.spinner(f"Processing '{uploaded.name}'..."):
-            chunks_count = process_pdf(uploaded)
-            if chunks_count is not None:
-                st.success(f"✅ PDF processed successfully! {chunks_count} chunks created.")
-                st.session_state.uploaded_file_name = uploaded.name
-            else:
-                st.error("❌ Failed to process PDF")
-                st.session_state.uploaded_file_name = None
-        st.experimental_rerun()
+# ---------------- UI COMPONENTS ----------------
 
-    st.markdown("---")
+# ✅ Problem #2: Title and Creator info at Top Left
+col_header, col_space = st.columns([0.6, 0.4])
+with col_header:
+    st.title("📘 PDF Assistant")
+    st.markdown("**Created by [Abhishek Saxena](https://www.linkedin.com/in/abhishek-iitr/)**")
+
+# Sidebar Controls
+with st.sidebar:
     st.header("Controls")
     st.button("🗑️ Clear Chat History", on_click=clear_chat_history, use_container_width=True)
     st.button("🔥 Clear PDF Memory", on_click=clear_memory, use_container_width=True)
-
+    
     st.markdown("---")
-    st.subheader("Status")
     if st.session_state.uploaded_file_name:
-        st.success(f"✅ Active PDF:\n`{st.session_state.uploaded_file_name}`")
+        st.success(f"✅ **Active PDF:**\n `{st.session_state.uploaded_file_name}`")
     else:
-        st.info("⬆️ Upload a PDF to start chatting!")
-
-# ---------------- MAIN HEADER (Top-left Title + Creator) ----------------
-# uses "main" margin via CSS
-st.markdown('<div class="main">', unsafe_allow_html=True)
-st.markdown(
-    """
-    <div class="header-left">
-        <div class="header-title">📘 PDF Assistant</div>
-        <div class="header-creator">Created by <a href="https://www.linkedin.com/in/abhishek-iitr/" target="_blank" style="color: #9fc2ff;">Abhishek Saxena</a></div>
-    </div>
-    """,
-    unsafe_allow_html=True,
-)
+        st.warning("⬆️ Upload a PDF to start chatting!")
 
-# ---------------- CHAT AREA ----------------
-st.markdown('<div class="chat-area">', unsafe_allow_html=True)
+# File Upload
+uploaded = st.file_uploader(
+    "Upload your PDF",
+    type=["pdf"],
+    key=st.session_state.uploader_key
+)
 
-if not st.session_state.chat:
-    st.markdown('<div style="color:rgba(255,255,255,0.55); padding:20px 0;">Ask a question about your document to start the conversation.</div>', unsafe_allow_html=True)
-else:
-    for role, msg in st.session_state.chat:
-        if role == "user":
-            st.markdown(f"<div class='chat-user'>{msg}</div>", unsafe_allow_html=True)
+if uploaded and uploaded.name != st.session_state.uploaded_file_name:
+    st.session_state.uploaded_file_name = None
+    st.session_state.chat = []
+    
+    with st.spinner(f"Processing '{uploaded.name}'..."):
+        chunks_count = process_pdf(uploaded)
+        
+        if chunks_count is not None:
+            st.success(f"✅ PDF processed successfully! {chunks_count} chunks created.")
+            st.session_state.uploaded_file_name = uploaded.name
         else:
-            st.markdown(f"<div class='chat-bot'>{msg}</div>", unsafe_allow_html=True)
-
-st.markdown("</div>", unsafe_allow_html=True)  # close chat-area
-
-# ---------------- INPUT BAR (Enter to submit + arrow button) ----------------
-st.markdown('<div class="input-bar">', unsafe_allow_html=True)
-st.markdown('<div class="input-row">', unsafe_allow_html=True)
-
-# Build a form: pressing Enter in the input will submit the form.
-with st.form(key="ask_form", clear_on_submit=True):
-    cols = st.columns([1, 0.12])
-    with cols[0]:
-        q = st.text_input(
-            "Type your question",
-            key="question_input",
-            placeholder="Ask anything about your PDF document...",
-            disabled=(st.session_state.uploaded_file_name is None or client is None),
+            st.error("❌ Failed to process PDF")
+            st.session_state.uploaded_file_name = None
+    
+    st.rerun()
+
+# ---------------- INPUT AREA ----------------
+# ✅ Problem #3: "Enter" key submission + Arrow button using st.form
+# We use a form so that pressing "Enter" on the keyboard submits the question.
+
+disabled_input = st.session_state.uploaded_file_name is None or client is None
+
+# Create a form container
+with st.form(key='chat_form', clear_on_submit=True):
+    # Use columns to put the input box and the button side-by-side
+    col_input, col_btn = st.columns([0.85, 0.15], gap="small")
+    
+    with col_input:
+        user_question = st.text_input(
+            "Ask a question", 
+            placeholder="Ask a question about the loaded PDF...",
             label_visibility="collapsed",
+            disabled=disabled_input
         )
-    with cols[1]:
-        # Arrow submit button (visible). Pressing Enter also triggers the form submit.
-        submit = st.form_submit_button("➤", help="Send (Enter or click)", disabled=(st.session_state.uploaded_file_name is None or client is None))
-
-st.markdown("</div></div>", unsafe_allow_html=True)  # close input-row and input-bar
-
-if submit and q:
-    # Append user message
-    st.session_state.chat.append(("user", q))
-
-    with st.spinner("Thinking..."):
-        answer, sources, error = ask_question(q)
-        if answer:
-            bot_msg = f"{answer}<div class='sources'>Context Chunks Used: {sources}</div>"
-            st.session_state.chat.append(("bot", bot_msg))
-        else:
-            st.session_state.chat.append(("bot", f"🔴 **Error:** {error}"))
+        
+    with col_btn:
+        # The arrow button acts as the submit button for the form
+        submit_btn = st.form_submit_button("➤", disabled=disabled_input, use_container_width=True)
+
+# Processing the Input (Run only when form is submitted)
+if submit_btn or (user_question and not disabled_input): 
+    # Note: Streamlit forms usually require the submit button click check, 
+    # but clear_on_submit=True handles the reset.
+    
+    if user_question:
+        # Add user query to chat history
+        st.session_state.chat.append(("user", user_question))
+        
+        # Get answer
+        with st.spinner("Thinking..."):
+            answer, sources, error = ask_question(user_question)
+            
+            if answer:
+                bot_message = f"{answer}<div class='sources'>Context Chunks Used: {sources}</div>"
+                st.session_state.chat.append(("bot", bot_message))
+            else:
+                st.session_state.chat.append(("bot", f"🔴 **Error:** {error}"))
+        
+        # Rerun to update the chat history display below
+        st.rerun()
+
+# ---------------- CHAT HISTORY DISPLAY ----------------
+st.markdown("---")
+st.markdown("## Chat History")
+
+# Display in reverse order (newest top) or standard (newest bottom)? 
+# Standard chat is newest bottom.
+for role, msg in st.session_state.chat:
+    if role == "user":
+        st.markdown(f"<div class='chat-user'>{msg}</div>", unsafe_allow_html=True)
+    else:
+        st.markdown(f"<div class='chat-bot'>{msg}</div>", unsafe_allow_html=True)
 
-    # Rerun so new messages show and form clears
-    st.experimental_rerun()
+# (Footer removed as requested, info moved to top)