Create app.py

app.py

@@ -0,0 +1,540 @@
+#!/usr/bin/env python3
+"""
+PDF Chat Web Application - Hugging Face Spaces Version
+======================================================
+A Streamlit web app for chatting with PDF documents using OpenAI.
+Deployed on Hugging Face Spaces for public access.
+"""
+
+import streamlit as st
+import os
+import tempfile
+import PyPDF2
+from io import BytesIO
+import requests
+import json
+
+# Page configuration
+st.set_page_config(
+    page_title="PDF Chat Assistant",
+    page_icon="📄",
+    layout="wide",
+    initial_sidebar_state="expanded"
+)
+
+# Custom CSS for modern dark theme
+st.markdown("""
+<style>
+    .stApp {
+        background: linear-gradient(135deg, #1e1e1e 0%, #2d2d2d 100%);
+        color: #ffffff;
+    }
+    
+    .main-header {
+        background: linear-gradient(135deg, #2d2d2d 0%, #3d3d3d 100%);
+        padding: 2rem;
+        border-radius: 15px;
+        text-align: center;
+        margin-bottom: 2rem;
+        box-shadow: 0 4px 6px rgba(0,0,0,0.3);
+        border: 1px solid #404040;
+    }
+    
+    .feature-card {
+        background: linear-gradient(135deg, #2d2d2d 0%, #3d3d3d 100%);
+        padding: 1.5rem;
+        border-radius: 10px;
+        margin: 1rem 0;
+        border: 1px solid #404040;
+        box-shadow: 0 2px 4px rgba(0,0,0,0.2);
+    }
+    
+    .user-message {
+        background: linear-gradient(135deg, #007bff 0%, #0056b3 100%);
+        color: white;
+        padding: 1rem;
+        border-radius: 15px;
+        margin: 0.5rem 0;
+        margin-left: 15%;
+        box-shadow: 0 2px 4px rgba(0,123,255,0.3);
+    }
+    
+    .ai-message {
+        background: linear-gradient(135deg, #495057 0%, #343a40 100%);
+        color: white;
+        padding: 1rem;
+        border-radius: 15px;
+        margin: 0.5rem 0;
+        margin-right: 15%;
+        box-shadow: 0 2px 4px rgba(73,80,87,0.3);
+    }
+    
+    .success-message {
+        background: linear-gradient(135deg, #28a745 0%, #20c997 100%);
+        color: white;
+        padding: 1rem;
+        border-radius: 10px;
+        margin: 1rem 0;
+        box-shadow: 0 2px 4px rgba(40,167,69,0.3);
+    }
+    
+    .warning-message {
+        background: linear-gradient(135deg, #ffc107 0%, #fd7e14 100%);
+        color: #212529;
+        padding: 1rem;
+        border-radius: 10px;
+        margin: 1rem 0;
+        box-shadow: 0 2px 4px rgba(255,193,7,0.3);
+    }
+    
+    .info-message {
+        background: linear-gradient(135deg, #17a2b8 0%, #20c997 100%);
+        color: white;
+        padding: 1rem;
+        border-radius: 10px;
+        margin: 1rem 0;
+        box-shadow: 0 2px 4px rgba(23,162,184,0.3);
+    }
+    
+    .stTextInput > div > div > input {
+        background-color: #3d3d3d;
+        color: white;
+        border: 2px solid #555;
+        border-radius: 10px;
+        padding: 0.5rem;
+    }
+    
+    .stTextInput > div > div > input:focus {
+        border-color: #007bff;
+        box-shadow: 0 0 0 0.2rem rgba(0,123,255,0.25);
+    }
+    
+    .stButton > button {
+        background: linear-gradient(135deg, #007bff 0%, #0056b3 100%);
+        color: white;
+        border: none;
+        border-radius: 10px;
+        padding: 0.5rem 1rem;
+        font-weight: 600;
+        transition: all 0.3s ease;
+    }
+    
+    .stButton > button:hover {
+        background: linear-gradient(135deg, #0056b3 0%, #004085 100%);
+        transform: translateY(-2px);
+        box-shadow: 0 4px 8px rgba(0,123,255,0.3);
+    }
+    
+    .upload-area {
+        border: 2px dashed #007bff;
+        border-radius: 15px;
+        padding: 2rem;
+        text-align: center;
+        background: rgba(0,123,255,0.1);
+        margin: 1rem 0;
+    }
+    
+    .stats-container {
+        display: grid;
+        grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
+        gap: 1rem;
+        margin: 1rem 0;
+    }
+    
+    .stat-card {
+        background: linear-gradient(135deg, #343a40 0%, #495057 100%);
+        padding: 1rem;
+        border-radius: 10px;
+        text-align: center;
+        border: 1px solid #404040;
+    }
+</style>
+""", unsafe_allow_html=True)
+
+class PDFChatBot:
+    def __init__(self):
+        self.pdf_text = ""
+        self.conversation_history = []
+        self.pdf_pages = 0
+        self.pdf_chars = 0
+    
+    def extract_pdf_text(self, pdf_file):
+        """Extract text from PDF using PyPDF2"""
+        try:
+            pdf_reader = PyPDF2.PdfReader(pdf_file)
+            text = ""
+            page_count = len(pdf_reader.pages)
+            
+            for page in pdf_reader.pages:
+                text += page.extract_text() + "\n"
+            
+            if not text.strip():
+                return False, "Could not extract text from PDF. The PDF might contain only images or be password protected."
+            
+            self.pdf_text = text
+            self.pdf_pages = page_count
+            self.pdf_chars = len(text)
+            
+            return True, f"Successfully extracted text from {page_count} pages ({len(text):,} characters)!"
+            
+        except Exception as e:
+            return False, f"Error reading PDF: {str(e)}"
+    
+    def ask_openai(self, question, api_key):
+        """Ask OpenAI directly using the API"""
+        try:
+            # Limit context to prevent token limits
+            context_limit = 3000
+            context = f"Based on the following document content, please answer the question accurately and concisely.\n\nDocument:\n{self.pdf_text[:context_limit]}\n\nQuestion: {question}"
+            
+            headers = {
+                "Authorization": f"Bearer {api_key}",
+                "Content-Type": "application/json"
+            }
+            
+            data = {
+                "model": "gpt-3.5-turbo",
+                "messages": [
+                    {"role": "system", "content": "You are a helpful AI assistant that answers questions about documents. Be accurate, concise, and helpful. If you cannot find the answer in the document, say so clearly."},
+                    {"role": "user", "content": context}
+                ],
+                "max_tokens": 1000,
+                "temperature": 0.1
+            }
+            
+            response = requests.post(
+                "https://api.openai.com/v1/chat/completions",
+                headers=headers,
+                json=data,
+                timeout=30
+            )
+            
+            if response.status_code == 200:
+                result = response.json()
+                answer = result['choices'][0]['message']['content']
+                
+                # Store in conversation history
+                self.conversation_history.append({"question": question, "answer": answer})
+                
+                return answer
+            elif response.status_code == 401:
+                return "❌ Invalid API key. Please check your OpenAI API key and try again."
+            elif response.status_code == 429:
+                return "⏳ Rate limit exceeded. Please wait a moment and try again."
+            else:
+                return f"❌ API Error: {response.status_code} - Please check your API key and try again."
+                
+        except requests.exceptions.Timeout:
+            return "⏳ Request timed out. Please try again."
+        except requests.exceptions.ConnectionError:
+            return "🌐 Connection error. Please check your internet connection."
+        except Exception as e:
+            return f"❌ Error: {str(e)}"
+
+def main():
+    # Initialize session state
+    if 'bot' not in st.session_state:
+        st.session_state.bot = PDFChatBot()
+    if 'messages' not in st.session_state:
+        st.session_state.messages = []
+    if 'pdf_processed' not in st.session_state:
+        st.session_state.pdf_processed = False
+    if 'uploaded_file_name' not in st.session_state:
+        st.session_state.uploaded_file_name = ""
+    
+    # Header
+    st.markdown("""
+    <div class="main-header">
+        <h1>📄 PDF Chat Assistant</h1>
+        <p style="font-size: 1.2em; margin: 0.5rem 0;">Upload any PDF and start an intelligent conversation with your document!</p>
+        <p style="color: #aaa; margin-top: 1rem;">Powered by OpenAI GPT • Built with ❤️ for Hugging Face Spaces</p>
+    </div>
+    """, unsafe_allow_html=True)
+    
+    # Sidebar
+    with st.sidebar:
+        st.markdown("### 🔑 Configuration")
+        
+        api_key = st.text_input(
+            "OpenAI API Key", 
+            type="password",
+            help="Enter your OpenAI API key to start chatting with PDFs",
+            placeholder="sk-..."
+        )
+        
+        if api_key:
+            st.success("✅ API Key Provided")
+        else:
+            st.error("❌ API Key Required")
+        
+        st.markdown("---")
+        
+        st.markdown("### 📚 How to Use")
+        st.markdown("""
+        1. **🔑 Enter your OpenAI API key** above
+        2. **📤 Upload a PDF file** using the uploader
+        3. **⏳ Wait** for text extraction (few seconds)
+        4. **💬 Ask questions** about your document
+        5. **🧠 Get AI-powered answers** instantly!
+        """)
+        
+        st.markdown("---")
+        
+        st.markdown("### 🎯 Features")
+        st.markdown("""
+        • 📄 **PDF Text Extraction**
+        • 🤖 **AI-Powered Q&A**
+        • 💾 **Conversation Memory**
+        • 🎨 **Beautiful Interface**
+        • 🚀 **Fast & Responsive**
+        • 🔒 **Privacy Focused**
+        """)
+        
+        st.markdown("---")
+        
+        if st.button("🗑️ Clear Chat History", use_container_width=True):
+            st.session_state.messages = []
+            st.session_state.bot = PDFChatBot()
+            st.session_state.pdf_processed = False
+            st.session_state.uploaded_file_name = ""
+            st.success("✅ Chat history cleared!")
+            st.rerun()
+        
+        # API Key Info
+        with st.expander("ℹ️ Get OpenAI API Key"):
+            st.markdown("""
+            **How to get your API key:**
+            
+            1. Go to [OpenAI Platform](https://platform.openai.com)
+            2. Sign up or log in to your account
+            3. Navigate to **API Keys** section
+            4. Click **"Create new secret key"**
+            5. Copy the key (starts with `sk-`)
+            6. Paste it in the field above
+            
+            **Note:** Your API key is only used for this session and is not stored anywhere.
+            """)
+        
+        # Status
+        st.markdown("---")
+        st.markdown("### 📊 Status")
+        
+        if st.session_state.pdf_processed:
+            st.success("✅ PDF Ready")
+            st.info(f"📄 {st.session_state.uploaded_file_name}")
+            
+            # Display PDF stats
+            bot = st.session_state.bot
+            st.markdown(f"""
+            **📈 Document Stats:**
+            - Pages: {bot.pdf_pages}
+            - Characters: {bot.pdf_chars:,}
+            - Conversations: {len(bot.conversation_history)}
+            """)
+        else:
+            st.warning("⏳ No PDF loaded")
+        
+        if api_key:
+            st.success("✅ API Connected")
+        else:
+            st.error("❌ API Key Missing")
+    
+    # Main content
+    col1, col2 = st.columns([1, 2])
+    
+    with col1:
+        st.markdown("### 📤 Upload Your PDF")
+        
+        uploaded_file = st.file_uploader(
+            "Choose a PDF file",
+            type="pdf",
+            help="Upload any PDF document (max 200MB)",
+            label_visibility="collapsed"
+        )
+        
+        if not uploaded_file:
+            st.markdown("""
+            <div class="upload-area">
+                <h3>📁 Drag & Drop Your PDF Here</h3>
+                <p>Or click "Browse files" above to select a PDF</p>
+                <br>
+                <p><small>📋 Supported: PDF files up to 200MB<br>
+                🔒 Your files are processed securely and not stored</small></p>
+            </div>
+            """, unsafe_allow_html=True)
+        
+        if uploaded_file and api_key:
+            if not st.session_state.pdf_processed or st.session_state.uploaded_file_name != uploaded_file.name:
+                with st.spinner("📖 Extracting text from your PDF..."):
+                    success, message = st.session_state.bot.extract_pdf_text(uploaded_file)
+                    
+                    if success:
+                        st.markdown(f"""
+                        <div class="success-message">
+                            <h4>✅ PDF Processed Successfully!</h4>
+                            <p>{message}</p>
+                        </div>
+                        """, unsafe_allow_html=True)
+                        
+                        st.session_state.pdf_processed = True
+                        st.session_state.uploaded_file_name = uploaded_file.name
+                        
+                        # Show file details
+                        file_size = uploaded_file.size / 1024  # KB
+                        bot = st.session_state.bot
+                        
+                        st.markdown(f"""
+                        <div class="info-message">
+                            <strong>📄 File:</strong> {uploaded_file.name}<br>
+                            <strong>📊 Size:</strong> {file_size:.1f} KB<br>
+                            <strong>📃 Pages:</strong> {bot.pdf_pages}<br>
+                            <strong>📝 Characters:</strong> {bot.pdf_chars:,}<br>
+                            <strong>🎯 Status:</strong> Ready for questions!
+                        </div>
+                        """, unsafe_allow_html=True)
+                    else:
+                        st.markdown(f"""
+                        <div class="warning-message">
+                            <h4>⚠️ Processing Failed</h4>
+                            <p>{message}</p>
+                        </div>
+                        """, unsafe_allow_html=True)
+        
+        elif uploaded_file and not api_key:
+            st.markdown("""
+            <div class="warning-message">
+                <h4>⚠️ API Key Required</h4>
+                <p>Please enter your OpenAI API key in the sidebar to process the PDF.</p>
+            </div>
+            """, unsafe_allow_html=True)
+        
+        # Example questions
+        if st.session_state.pdf_processed:
+            st.markdown("### 💡 Try These Questions")
+            
+            example_questions = [
+                "📋 What is this document about?",
+                "📝 Summarize the main points",
+                "🔍 What are the key details?",
+                "📊 Give me important information",
+                "❓ What questions can I ask?"
+            ]
+            
+            for question in example_questions:
+                if st.button(question, key=f"example_{question}", use_container_width=True):
+                    # Trigger the question
+                    question_text = question.split(" ", 1)[1]  # Remove emoji
+                    st.session_state.pending_question = question_text
+                    st.rerun()
+    
+    with col2:
+        st.markdown("### 💬 Chat with Your PDF")
+        
+        # Chat container
+        chat_container = st.container()
+        
+        with chat_container:
+            if st.session_state.messages:
+                for message in st.session_state.messages:
+                    if message["role"] == "user":
+                        st.markdown(f"""
+                        <div class="user-message">
+                            <strong>🧑 You:</strong> {message["content"]}
+                        </div>
+                        """, unsafe_allow_html=True)
+                    else:
+                        st.markdown(f"""
+                        <div class="ai-message">
+                            <strong>🤖 AI:</strong> {message["content"]}
+                        </div>
+                        """, unsafe_allow_html=True)
+            else:
+                if st.session_state.pdf_processed:
+                    st.markdown("""
+                    <div class="ai-message">
+                        <strong>🤖 AI:</strong> Hello! I've analyzed your PDF document. What would you like to know about it? Feel free to ask any questions!
+                    </div>
+                    """, unsafe_allow_html=True)
+                else:
+                    st.markdown("""
+                    <div class="feature-card" style="text-align: center; padding: 3rem;">
+                        <h3>👋 Welcome to PDF Chat Assistant!</h3>
+                        <p style="font-size: 1.1em; margin: 1rem 0;">Transform any PDF into an interactive conversation</p>
+                        <br>
+                        <div class="stats-container">
+                            <div class="stat-card">
+                                <h4>📄 Smart</h4>
+                                <p>AI understands your documents</p>
+                            </div>
+                            <div class="stat-card">
+                                <h4>⚡ Fast</h4>
+                                <p>Instant answers to your questions</p>
+                            </div>
+                            <div class="stat-card">
+                                <h4>🔒 Secure</h4>
+                                <p>Your data stays private</p>
+                            </div>
+                        </div>
+                        <br>
+                        <p><strong>Get started:</strong> Add your API key and upload a PDF!</p>
+                    </div>
+                    """, unsafe_allow_html=True)
+        
+        # Input area
+        st.markdown("---")
+        
+        # Check for pending question from example buttons
+        if hasattr(st.session_state, 'pending_question'):
+            user_question = st.session_state.pending_question
+            del st.session_state.pending_question
+        else:
+            user_question = st.text_input(
+                "Ask a question about your PDF:",
+                placeholder="e.g., What are the main topics discussed in this document?",
+                disabled=not st.session_state.pdf_processed,
+                key="user_input"
+            )
+        
+        col_btn1, col_btn2, col_btn3 = st.columns([2, 1, 1])
+        
+        with col_btn1:
+            send_button = st.button("📤 Send Message", disabled=not st.session_state.pdf_processed, use_container_width=True)
+        
+        with col_btn2:
+            if st.button("🔄 Refresh", disabled=not st.session_state.pdf_processed, use_container_width=True):
+                st.rerun()
+        
+        # Process question
+        if (send_button or hasattr(st.session_state, 'pending_question')) and user_question and st.session_state.pdf_processed and api_key:
+            # Add user message
+            st.session_state.messages.append({"role": "user", "content": user_question})
+            
+            # Get AI response
+            with st.spinner("🤖 AI is analyzing your question..."):
+                ai_response = st.session_state.bot.ask_openai(user_question, api_key)
+            
+            # Add AI response
+            st.session_state.messages.append({"role": "assistant", "content": ai_response})
+            
+            st.rerun()
+        
+        elif send_button and not st.session_state.pdf_processed:
+            st.warning("⚠️ Please upload and process a PDF first!")
+        
+        elif send_button and not api_key:
+            st.warning("⚠️ Please enter your OpenAI API key in the sidebar!")
+
+    # Footer
+    st.markdown("---")
+    st.markdown("""
+    <div style="text-align: center; color: #888; padding: 2rem;">
+        <h4>🚀 PDF Chat Assistant</h4>
+        <p>Made with ❤️ using Streamlit • Powered by OpenAI GPT-3.5 • Hosted on 🤗 Hugging Face Spaces</p>
+        <p><small>📄 Upload PDFs • 💬 Ask Questions • 🧠 Get AI Answers • 🔒 Privacy First</small></p>
+        <br>
+        <p><small>⭐ Like this app? Give it a star on Hugging Face Spaces!</small></p>
+    </div>
+    """, unsafe_allow_html=True)
+
+if __name__ == "__main__":
+    main()