app.py

import os
import gradio as gr
from anthropic import Anthropic
from pypdf import PdfReader
from sklearn.feature_extraction.text import TfidfVectorizer
from sklearn.metrics.pairwise import cosine_similarity

# Set up your Anthropic API key in HF secrets
ANTHROPIC_API_KEY = os.getenv('ANTHROPIC_API_KEY')
os.environ["ANTHROPIC_API_KEY"] = ANTHROPIC_API_KEY

# Set up username and password in HF secrets
username = os.getenv('username')
password = os.getenv('password')

# Function to chunk the document
def chunk_text(text, chunk_size=1000, overlap=100):
    chunks = []
    start = 0
    while start < len(text):
        end = start + chunk_size
        chunk = text[start:end]
        chunks.append(chunk)
        start = end - overlap
    return chunks

# Function to find the most relevant chunks
def get_relevant_chunks(query, chunks, top_n=3):
    vectorizer = TfidfVectorizer()
    tfidf_matrix = vectorizer.fit_transform(chunks + [query])
    cosine_similarities = cosine_similarity(tfidf_matrix[-1], tfidf_matrix[:-1]).flatten()
    relevant_indices = cosine_similarities.argsort()[-top_n:][::-1]
    return [chunks[i] for i in relevant_indices]

# Add the path to your desired knowledge base
reference_document = "Rosenshine+Principles.pdf" 
reader = PdfReader(reference_document)
full_text = ''.join(page.extract_text() for page in reader.pages)
text_chunks = chunk_text(full_text)
    
def chat_with_assistant(message, history):
    # Find relevant chunks based on the user message
    relevant_chunks = get_relevant_chunks(message, text_chunks)
    context = "\n".join(relevant_chunks)
    
    # Prepare the system message
    system_message = f"""You are an AI assistant answering questions based on a reference document. 
    You provide short, clear answers in simple language.
    Use the following as context for all of your answers:
    {context}
    """

    # Customize instructions as needed
    instructions = """
    You provide useful examples and similes.
    """
    system_message += instructions
                  
    # Prepare the message array
    messages = []
    
    # Add conversation history
    for human_msg, ai_msg in history:
        messages.append({"role": "user", "content": human_msg})
        messages.append({"role": "assistant", "content": ai_msg})
    
    # Add the current user message
    messages.append({"role": "user", "content": message})
    
    # Create Anthropic client
    client = Anthropic(api_key=os.environ["ANTHROPIC_API_KEY"])
    
    # Make the API call
    response = client.messages.create(
        model="claude-3-5-sonnet-20240620",
       #model="claude-3-haiku-20240307", 
        max_tokens=500,
        system=system_message,
        messages=messages
    )
    
    return response.content[0].text.strip()

# CSS for an Anthropic-looking style
anthropic_theme = gr.themes.Default().set(
    body_background_fill="#FAF9F6",  # Light beige background
    block_background_fill="#FFFFFF",  # White for input blocks
    block_title_text_color="#4A4A4A",  # Dark gray for text
    block_label_background_fill="#F6E3CE",  # Very light orange for labels
    input_background_fill="#FFFFFF",  # White for input fields
    button_primary_background_fill="#D97758",  # Anthropic orange for primary buttons
    button_primary_background_fill_hover="#8A2BE2",  # Darker orange for hover
    button_primary_text_color="#FFFFFF",  # White text on buttons
    button_secondary_background_fill="#F5D0A9",  # Light orange for secondary buttons
    button_secondary_background_fill_hover="#F5D0A9",  # Slightly darker orange for hover
    button_secondary_text_color="#4A4A4A",  # Dark gray text for secondary buttons
    block_border_width="1px",
    block_border_color="#E0E0E0",  # Light gray border
)

# Gradio interface
iface = gr.ChatInterface(
    chat_with_assistant,
    chatbot=gr.Chatbot(height=500),
    textbox=gr.Textbox(placeholder="Type your message here...", container=False, scale=7),

# Change name and description as desired
    title="Claude Custom Assistant",
    description="Chat with an AI assistant powered by Claude 3.5 Sonnet, customs instructions, and a reference document",
    theme=anthropic_theme,

# Change examples as desired
    examples=["What are the key principles of instructional design?", "What might be barriers to learning?"],
    cache_examples=True,
    retry_btn=None,
    undo_btn="Delete Previous",
    clear_btn="Clear",
)

iface.launch(auth=(username, password))