main.py

from flask import Flask, request, jsonify
from dotenv import load_dotenv
import os
import pymongo
import google.generativeai as genai
from flask_cors import CORS
from tqdm import tqdm

# Load environment variables from .env file
load_dotenv()

# Access the key
MONGODB_URI = os.getenv('MONGODB_URI')
EMBEDDING_MODEL = os.getenv('EMBEDDING_MODEL') or 'keepitreal/vietnamese-sbert'
DB_NAME = os.getenv('DB_NAME')
DB_COLLECTION = os.getenv('DB_COLLECTION')
GEMINI_KEY = os.getenv('GEMINI_KEY')
genai.configure(api_key=GEMINI_KEY)
model = genai.GenerativeModel('gemini-1.5-pro')

client = pymongo.MongoClient(MONGODB_URI)
db = client[DB_NAME] 
collection = db[DB_COLLECTION]

app = Flask(__name__)
CORS(app)

from sentence_transformers import SentenceTransformer
embedding_model = SentenceTransformer(EMBEDDING_MODEL)

def vector_search(user_query, collection, limit=4):
    """
    Perform a vector search in the MongoDB collection based on the user query.

    Args:
    user_query (str): The user's query string.
    collection (MongoCollection): The MongoDB collection to search.

    Returns:
    list: A list of matching documents.
    """

    # Generate embedding for the user query
    query_embedding = get_embedding(user_query)

    if query_embedding is None:
        return "Invalid query or embedding generation failed."

    # Define the vector search pipeline
    vector_search_stage = {
        "$vectorSearch": {
            "index": "vector_index",
            "queryVector": query_embedding,
            "path": "embedding",
            "numCandidates": 150,
            "limit": limit,
        }
    }

    unset_stage = {
        "$unset": "embedding" 
    }

    project_stage = {
        "$project": {
            "_id": 0,
            "title": 1,
            "details": 1,
            "price": 1,
            "promotion_price": 1,
            "size_options": 1,
            "gender_options": 1,
            "quantity": 1,
            "stock": 1,
            "is_shoes": 1,
            "is_sandals": 1,
        }
    }

    pipeline = [vector_search_stage, unset_stage, project_stage]

    # Execute the search
    results = collection.aggregate(pipeline)

    return list(results)

def get_search_result(query, collection):
    get_knowledge = vector_search(query, collection, 10)
    search_result = ""
    i = 0
    for result in get_knowledge:
        # print(result)
        i += 1
        if result.get('price'):
            search_result += f"\n\nSản phẩm {i+1}: {result.get('title')}, Giá: {result.get('price')}"
        
        if result.get('promotion_price'):
            search_result += f", Giá ưu đãi: {result.get('promotion_price')}"

        if result.get('stock'):
            search_result += f", Trạng thái: {result.get('stock')}"

        if result.get('is_shoes') == True:
            search_result += f", Loại: Giày"

        if result.get('is_sandals') == True:
            search_result += f", Loại: Dép"

        if result.get('size_options'):
            search_result += f", Size: {result.get('size_options')}"

        if result.get('gender_options'):
            search_result += f", Dành cho: {result.get('gender_options')}"

        if result.get('details'):
            search_result += f", Chi tiết sản phẩm: {result.get('details')}"
            
    return search_result

def get_embedding(text):
    if not text.strip():
        print("Attempted to get embedding for empty text.")
        return []

    embedding = embedding_model.encode(text)
    return embedding.tolist()


def process_query(query):
    return query.lower()

@app.route('/api/search', methods=['POST'])
def handle_query():
    data = request.get_json()
    query = process_query(data.get('question'))

    if not query:
        return jsonify({'error': 'No query provided'}), 400

    # Retrieve data from vector database

    source_information = get_search_result(query, collection).replace('<br>', '\n')
    combined_information = f"Hãy trở thành chuyên gia tư vấn bán hàng cho một website bán giày dép ThuThaoShoes. Câu hỏi của khách hàng: {query}\nTrả lời câu hỏi dựa vào các thông tin sản phẩm dưới đây: {source_information}."

    response = model.generate_content(combined_information)
    
    return jsonify({
        'content': response.text
        })


@app.route('/api/embedding', methods=['GET'])
def get_embedding_api():

    # Lấy tất cả các tài liệu từ collection
    documents = list(collection.find({}))

    for doc in tqdm(documents, desc="Processing documents"):
        product_specs = doc.get('title', '')
        product_cat = doc.get('category', '')
        print(product_specs + ' ' + product_cat)
        embedding = get_embedding(product_specs + ' Danh mục: ' + product_cat)
        
        if embedding is not None:
            # Cập nhật tài liệu với embedding mới
            collection.update_one(
                {'_id': doc['_id']},
                {'$set': {'embedding': embedding}}
        )
            
    return jsonify({'message': 'Embedding cập nhật thành công cho tất cả các tài liệu.'})

if __name__ == '__main__':
    app.run(debug=True)