app.py

import streamlit as st
import pickle
import pandas as pd
from sentence_transformers import SentenceTransformer
from sentence_transformers import models
import numpy as np

res = pd.read_csv('qa2.csv')

# Load pre-computed embeddings
with open("embeddings_words.pkl", "rb") as f:
    embedded_texts = pickle.load(f)

# Define model
model_name = 'kornwtp/simcse-model-phayathaibert'
word_embedding_model = models.Transformer(model_name)
pooling_model = models.Pooling(word_embedding_model.get_word_embedding_dimension(), pooling_mode='cls')  # Use CLS token for representation
model = SentenceTransformer(modules=[word_embedding_model, pooling_model])

# Streamlit UI setup with custom CSS for styling
st.title("Thai Legal Chat Bot", anchor="top")
st.markdown("""
    <style>
        .css-1kyxreq { display: none; }  # Hide the Streamlit default hamburger menu
        .stApp { background-color: #F4F8FC; }
        .stChatMessage-User { background-color: #4CAF50; color: white; padding: 15px; border-radius: 12px; margin-bottom: 10px; }
        .stChatMessage-Assistant { background-color: #2196F3; color: white; padding: 15px; border-radius: 12px; margin-bottom: 10px; }
        .stButton { background-color: #4CAF50; color: white; padding: 12px 25px; font-size: 18px; border-radius: 12px; }
        .stTextInput { border-radius: 12px; padding: 10px; font-size: 16px; }
        .stTextInput input { background-color: #f7f7f7; border: none; color: #333; }
        .stMarkdown { font-size: 18px; font-family: 'Arial', sans-serif; line-height: 1.5; }
    </style>
    """, unsafe_allow_html=True)

# Initialize session state for messages
if "messages" not in st.session_state:
    st.session_state.messages = []

# Display existing chat messages
for message in st.session_state.messages:
    with st.chat_message(message["role"]):
        st.markdown(message["content"])

# Display a greeting message
with st.chat_message("ai"):
    st.write("สวัสดี! 😊")

# Get user input
if prompt := st.chat_input("พิมพ์ข้อความที่นี่ ..."):
    st.session_state.messages.append({"role": "user", "content": prompt})
    with st.chat_message("user"):
        st.markdown(prompt)

    # Show a loading spinner while processing
    with st.spinner("กำลังค้นหาคำตอบ..."):
        # Encode the user's prompt and calculate similarities
        b = model.encode([prompt], normalize_embeddings=True)
        inner_products = np.inner(b, embedded_texts)  # Calculate inner products
        
        # Get the index of the highest value
        top_index = np.argmax(inner_products)
        inner_products = inner_products.flatten()
        similarity_percent = str(round(inner_products[top_index],2))
        answer = f"{similarity_percent}% : {res['A'][top_index]}"

        with st.chat_message("assistant"):
            st.write(answer)

        # Save the assistant's answer in session state
        st.session_state.messages.append({"role": "assistant", "content": answer})

    st.success("คำตอบเสร็จสิ้นแล้ว! 😊", icon="✅")