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import os
import subprocess
import sys
from langchain_community.embeddings import OpenAIEmbeddings
from dotenv import load_dotenv

def install_packages():
    # List of packages to install in separate batches
    packages_batches = [
        ["langchain", "langchain-openai", "langchain_core", "langchain-community", "langchainhub", "openai", "langchain-qdrant"],
        ["qdrant-client", "pymupdf", "pandas"],
        ["llama-index", "--no-cache-dir"],
        ["llama-parse", "PyPDF2", "tiktoken"],
        ["langchain-text-splitters"],
        ["PyPDF2"],
        ["scikit-learn"]
    ]

    # Install each batch of packages
    for package_list in packages_batches:
        try:
            print(f"Installing: {' '.join(package_list)}")
            subprocess.check_call([sys.executable, "-m", "pip", "install"] + package_list)
            print(f"Successfully installed: {' '.join(package_list)}\n")
        except subprocess.CalledProcessError as e:
            print(f"Failed to install {package_list}: {e}\n")

# Call the function to install the packages
if __name__ == "__main__":
    install_packages()

# Load environment variables from .env file
load_dotenv()

# Get the OpenAI API key from the environment variables
api_key = os.getenv("OPENAI_API_KEY")

# Check if the API key is loaded
if not api_key:
    print("OpenAI API key not found. Please ensure it is set in the .env file.")
else:
    print("OpenAI API key loaded successfully.")


import nest_asyncio
nest_asyncio.apply()

# Function to extract text from PDF URLs
import re
import requests
from PyPDF2 import PdfReader
from io import BytesIO

# URLs for the two PDFs
pdf_urls = [
    "https://www.whitehouse.gov/wp-content/uploads/2022/10/Blueprint-for-an-AI-Bill-of-Rights.pdf",
    "https://nvlpubs.nist.gov/nistpubs/ai/NIST.AI.600-1.pdf"
]

def extract_text_from_pdf(url):
    response = requests.get(url)
    pdf_file = BytesIO(response.content)
    reader = PdfReader(pdf_file)

    pdf_text = ""
    for page in reader.pages:
        pdf_text += page.extract_text()

    cleaned_text = pdf_text.replace("\n", " ").replace("\r", " ").strip()
    cleaned_text = " ".join(cleaned_text.split())

    sentences = re.split(r'(?<=[.!?]) +', cleaned_text)
    return sentences

# Extract text from both PDFs
sentences_list = []
for url in pdf_urls:
    sentences = extract_text_from_pdf(url)
    sentences_list.append(sentences)
    print(f"Extracted {len(sentences)} sentences from {url}")



# Semantic chunking
from langchain.embeddings.openai import OpenAIEmbeddings
from sklearn.metrics.pairwise import cosine_similarity
import tiktoken
import numpy as np

embedding_model = OpenAIEmbeddings()
flat_sentences = [sentence for sublist in sentences_list for sentence in sublist]
embeddings = embedding_model.embed_documents(flat_sentences)

def greedy_chunk_sentences(sentences, sentence_embeddings, max_chunk_size=1000, similarity_threshold=0.75):
    chunks = []
    current_chunk = []
    current_chunk_tokens = 0
    encoder = tiktoken.get_encoding("cl100k_base")

    for i, sentence in enumerate(sentences):
        sentence_tokens = len(encoder.encode(sentence))

        if current_chunk:
            similarity = cosine_similarity([sentence_embeddings[i]], [sentence_embeddings[i - 1]])[0][0]
            if similarity < similarity_threshold or current_chunk_tokens + sentence_tokens > max_chunk_size:
                chunks.append(" ".join(current_chunk))
                current_chunk = []
                current_chunk_tokens = 0

        current_chunk.append(sentence)
        current_chunk_tokens += sentence_tokens

    if current_chunk:
        chunks.append(" ".join(current_chunk))

    return chunks

# Perform greedy chunking
semantic_chunks = greedy_chunk_sentences(sentences_list[0], embeddings)


# Qdrant setup for storing chunks
from qdrant_client import QdrantClient
from qdrant_client.http.models import Distance, VectorParams
from langchain_qdrant import QdrantVectorStore
from langchain.schema import Document
import uuid

LOCATION = ":memory:"
COLLECTION_NAME = "Semantic_Chunking"

qdrant_client = QdrantClient(LOCATION)

qdrant_client.create_collection(
    collection_name=COLLECTION_NAME,
    vectors_config=VectorParams(size=1536, distance=Distance.COSINE)
)

qdrant_vector_store = QdrantVectorStore(
    client=qdrant_client,
    collection_name=COLLECTION_NAME,
    embedding=embedding_model,
)

documents = [Document(page_content=chunk, metadata={"source": "generated"}, id=str(uuid.uuid4())) for chunk in semantic_chunks]
qdrant_vector_store.add_documents(documents)

# Retrieve data from Qdrant
retriever = qdrant_vector_store.as_retriever()

# Define prompt and execute RAG chain
from langchain.prompts import ChatPromptTemplate
from operator import itemgetter
from langchain_openai import ChatOpenAI
from langchain_core.output_parsers import StrOutputParser
from langchain_core.runnables import RunnablePassthrough

template = """
### You are a helpful assistant. Use the available context to answer the question. If you can't answer the question, say you don't know.

Question:
{question}

Context:
{context}
"""

prompt = ChatPromptTemplate.from_template(template)

primary_qa_llm = ChatOpenAI(model_name="gpt-4o-mini", temperature=0)

retrieval_augmented_qa_chain = (
    {"context": itemgetter("question") | retriever, "question": itemgetter("question")}
    | RunnablePassthrough.assign(context=itemgetter("context"))
    | {"response": prompt | primary_qa_llm, "context": itemgetter("context")}
)

# Query the RAG chain
question = "What are the top AI risks and how to best manage them?"
result = retrieval_augmented_qa_chain.invoke({"question": question})

print(result["response"].content)