Create app.py

interim/app.py

@@ -0,0 +1,326 @@
+# to-do: Enable downloading multiple patent PDFs via corresponding links 
+import sys
+import os
+import re
+import shutil
+import time
+import fitz 
+import streamlit as st
+import nltk
+import tempfile
+import subprocess
+
+# Pin NLTK to version 3.9.1
+REQUIRED_NLTK_VERSION = "3.9.1"
+subprocess.run([sys.executable, "-m", "pip", "install", f"nltk=={REQUIRED_NLTK_VERSION}"])
+
+# Set up temporary directory for NLTK resources
+nltk_data_path = os.path.join(tempfile.gettempdir(), "nltk_data")
+os.makedirs(nltk_data_path, exist_ok=True)
+nltk.data.path.append(nltk_data_path)
+
+# Download 'punkt_tab' for compatibility
+try:
+    print("Ensuring NLTK 'punkt_tab' resource is downloaded...")
+    nltk.download("punkt_tab", download_dir=nltk_data_path)
+except Exception as e:
+    print(f"Error downloading NLTK 'punkt_tab': {e}")
+    raise e
+
+sys.path.append(os.path.abspath("."))
+from langchain.chains import ConversationalRetrievalChain
+from langchain.memory import ConversationBufferMemory
+from langchain.llms import OpenAI
+from langchain.document_loaders import UnstructuredPDFLoader
+from langchain.vectorstores import Chroma
+from langchain.embeddings import HuggingFaceEmbeddings
+from langchain.text_splitter import NLTKTextSplitter
+from patent_downloader import PatentDownloader
+from langchain.document_loaders import PyMuPDFLoader
+from langchain.text_splitter import RecursiveCharacterTextSplitter
+
+PERSISTED_DIRECTORY = tempfile.mkdtemp()
+
+# Fetch API key securely from the environment
+OPENAI_API_KEY = os.getenv("OPENAI_API_KEY")
+if not OPENAI_API_KEY:
+    st.error("Critical Error: OpenAI API key not found in the environment variables. Please configure it.")
+    st.stop()
+
+def check_poppler_installed():
+    if not shutil.which("pdfinfo"):
+        raise EnvironmentError(
+            "Poppler is not installed or not in PATH. Install 'poppler-utils' for PDF processing."
+        )
+
+check_poppler_installed()
+
+def load_docs(document_path):
+    try:
+        import fitz  # PyMuPDF for text extraction
+
+        # Step 1: Extract plain text from PDF
+        doc = fitz.open(document_path)
+        extracted_text = []
+
+        for page_num, page in enumerate(doc):
+            page_text = page.get_text("text")  # Extract text
+            clean_page_text = clean_extracted_text(page_text)
+            if clean_page_text:  # Keep only non-empty cleaned text
+                extracted_text.append(clean_page_text)
+
+        doc.close()
+
+        # Step 2: Combine cleaned text
+        full_text = "\n".join(extracted_text)
+        st.write(f"📄 Total Cleaned Text Length: {len(full_text)} characters")
+
+        # Step 3: Chunk the cleaned text
+        text_splitter = RecursiveCharacterTextSplitter(
+            chunk_size=1000,
+            chunk_overlap=100,
+            separators=["\n\n", "\n", " ", ""]
+        )
+        split_docs = text_splitter.create_documents([full_text])
+
+        # Debug: Show filtered chunks
+        st.write(f"🔍 Total Chunks After Splitting: {len(split_docs)}")
+        for i, doc in enumerate(split_docs[:5]):  # Show first 5 chunks
+            st.write(f"Chunk {i + 1}: {doc.page_content[:300]}...")
+
+        return split_docs
+    except Exception as e:
+        st.error(f"Failed to load and process PDF: {e}")
+        st.stop()
+
+
+def clean_extracted_text(text):
+    """
+    Cleans extracted text to remove metadata, headers, and irrelevant content.
+    """
+    lines = text.split("\n")
+    cleaned_lines = []
+
+    for line in lines:
+        line = line.strip()
+
+        # Filter out lines with metadata patterns
+        if (
+            re.match(r"^(U\.S\.|United States|Sheet|Figure|References|Patent No|Date of Patent)", line)
+            or re.match(r"^\(?\d+\)?$", line)  # Matches single numbers (page numbers)
+            or "Examiner" in line
+            or "Attorney" in line
+            or len(line) < 30  # Skip very short lines
+        ):
+            continue
+
+        cleaned_lines.append(line)
+
+    return "\n".join(cleaned_lines)
+
+
+def already_indexed(vectordb, file_name):
+    indexed_sources = set(
+        x["source"] for x in vectordb.get(include=["metadatas"])["metadatas"]
+    )
+    return file_name in indexed_sources
+
+def load_chain(file_name=None):
+    loaded_patent = st.session_state.get("LOADED_PATENT")
+
+    # Debug: Check PERSISTED_DIRECTORY
+    st.write(f"Using Persisted Directory: {PERSISTED_DIRECTORY}")
+    vectordb = Chroma(
+        persist_directory=PERSISTED_DIRECTORY,
+        embedding_function=HuggingFaceEmbeddings(),
+    )
+
+    # Debug: Confirm already indexed
+    if loaded_patent == file_name or already_indexed(vectordb, file_name):
+        st.write("✅ Already indexed.")
+    else:
+        st.write("🔄 Starting document processing and vectorstore update...")
+        
+        # Remove existing collection and load new docs
+        vectordb.delete_collection()
+        docs = load_docs(file_name)
+
+        # Debug: Verify text chunking
+        st.write(f"🔍 Number of Documents Loaded: {len(docs)}")
+        for i, doc in enumerate(docs[:5]):  # Show first 5 chunks for debugging
+            st.write(f"Chunk {i + 1}: {doc.page_content[:200]}...")
+
+        # Update vectorstore
+        vectordb = Chroma.from_documents(
+            docs, HuggingFaceEmbeddings(), persist_directory=PERSISTED_DIRECTORY
+        )
+        vectordb.persist()
+        st.write("✅ Vectorstore successfully updated and persisted.")
+
+        # Save loaded patent in session state
+        st.session_state["LOADED_PATENT"] = file_name
+
+    # Debug: Check vectorstore indexing
+    indexed_docs = vectordb.get(include=["documents"])
+    st.write(f"✅ Indexed Documents in Vectorstore: {len(indexed_docs['documents'])}")
+    for i, doc in enumerate(indexed_docs["documents"][:3]):  # Show first 3 indexed docs
+        st.write(f"Indexed Doc {i + 1}: {doc[:200]}...")
+
+    # Test retrieval with a sample query
+    retriever = vectordb.as_retriever(search_kwargs={"k": 3})
+    test_query = "What is this document about?"
+    results = retriever.get_relevant_documents(test_query)
+
+    # Debug: Verify document retrieval
+    st.write("🔍 Test Retrieval Results for Query:")
+    if results:
+        for i, res in enumerate(results):
+            st.write(f"Retrieved Doc {i + 1}: {res.page_content[:200]}...")
+    else:
+        st.warning("No documents retrieved for test query.")
+
+    # Configure memory for conversation
+    memory = ConversationBufferMemory(
+        memory_key="chat_history",
+        return_messages=True,
+        input_key="question",
+        output_key="answer",
+    )
+
+    return ConversationalRetrievalChain.from_llm(
+        OpenAI(temperature=0, openai_api_key=OPENAI_API_KEY),
+        retriever,
+        return_source_documents=False,
+        memory=memory,
+    )
+
+def extract_patent_number(url):
+    pattern = r"/patent/([A-Z]{2}\d+)"
+    match = re.search(pattern, url)
+    return match.group(1) if match else None
+
+def download_pdf(patent_number):
+    try:
+        patent_downloader = PatentDownloader(verbose=True)
+        output_path = patent_downloader.download(patents=patent_number, output_path=tempfile.gettempdir())
+        return output_path[0]
+    except Exception as e:
+        st.error(f"Failed to download patent PDF: {e}")
+        st.stop()
+
+def preview_pdf(pdf_path):
+    """Generate and display the first page of the PDF as an image."""
+    try:
+        doc = fitz.open(pdf_path)  # Open PDF
+        first_page = doc[0]  # Extract the first page
+        pix = first_page.get_pixmap()  # Render page to a Pixmap (image)
+        temp_image_path = os.path.join(tempfile.gettempdir(), "pdf_preview.png")
+        pix.save(temp_image_path)  # Save the image temporarily
+        return temp_image_path
+    except Exception as e:
+        st.error(f"Error generating PDF preview: {e}")
+        return None
+
+if __name__ == "__main__":
+    st.set_page_config(
+        page_title="Patent Chat: Google Patents Chat Demo",
+        page_icon="📖",
+        layout="wide",
+        initial_sidebar_state="expanded",
+    )
+    st.header("📖 Patent Chat: Google Patents Chat Demo")
+
+    # Input for Google Patent Link
+    patent_link = st.text_area(
+        "Enter Google Patent Link:", 
+        value="https://patents.google.com/patent/US8676427B1/en", 
+        height=100
+    )
+
+    # Initialize session state
+    for key in ["LOADED_PATENT", "pdf_preview", "loaded_pdf_path", "chain", "messages"]:
+        if key not in st.session_state:
+            st.session_state[key] = None
+
+    # Button to load and process patent
+    if st.button("Load and Process Patent"):
+        if not patent_link:
+            st.warning("Please enter a valid Google patent link.")
+            st.stop()
+
+        # Extract patent number
+        patent_number = extract_patent_number(patent_link)
+        if not patent_number:
+            st.error("Invalid patent link format.")
+            st.stop()
+
+        st.write(f"Patent number: **{patent_number}**")
+
+        # File handling
+        pdf_path = os.path.join(tempfile.gettempdir(), f"{patent_number}.pdf")
+        if not os.path.isfile(pdf_path):
+            st.write("📥 Downloading patent file...")
+            try:
+                pdf_path = download_pdf(patent_number)
+                st.write(f"✅ File downloaded: {pdf_path}")
+            except Exception as e:
+                st.error(f"Failed to download patent: {e}")
+                st.stop()
+        else:
+            st.write("✅ File already downloaded.")
+
+        # Generate PDF preview only if not already displayed
+        if not st.session_state.get("pdf_preview_displayed", False):
+            st.write("🖼️ Generating PDF preview...")
+            preview_image_path = preview_pdf(pdf_path)
+            if preview_image_path:
+                st.session_state.pdf_preview = preview_image_path
+                st.image(preview_image_path, caption="First Page Preview", use_container_width=True)
+                st.session_state["pdf_preview_displayed"] = True
+            else:
+                st.warning("Failed to generate PDF preview.")
+                st.session_state.pdf_preview = None
+
+        # Load the document into the system
+        st.write("🔄 Loading document into the system...")
+        try:
+            st.session_state.chain = load_chain(pdf_path)
+            st.session_state.LOADED_PATENT = patent_number
+            st.session_state.loaded_pdf_path = pdf_path
+            st.session_state.messages = [{"role": "assistant", "content": "Hello! How can I assist you with this patent?"}]
+            st.success("🚀 Document successfully loaded! You can now start asking questions.")
+        except Exception as e:
+            st.error(f"Failed to load the document: {e}")
+            st.stop()
+
+    # Display previous chat messages
+    if st.session_state.messages:
+        for message in st.session_state.messages:
+            with st.chat_message(message["role"]):
+                st.markdown(message["content"])
+
+    # User input for questions
+    if st.session_state.chain:
+        if user_input := st.chat_input("What is your question?"):
+            # User message
+            st.session_state.messages.append({"role": "user", "content": user_input})
+            with st.chat_message("user"):
+                st.markdown(user_input)
+
+            # Assistant response
+            with st.chat_message("assistant"):
+                message_placeholder = st.empty()
+                full_response = ""
+
+                with st.spinner("Generating response..."):
+                    try:
+                        # Generate response using the chain
+                        assistant_response = st.session_state.chain({"question": user_input})
+                        full_response = assistant_response.get("answer", "I'm sorry, I couldn't process that question.")
+                    except Exception as e:
+                        full_response = f"An error occurred: {e}"
+
+                message_placeholder.markdown(full_response)
+                st.session_state.messages.append({"role": "assistant", "content": full_response})
+    else:
+        st.info("Press the 'Load and Process Patent' button to start processing.")