app.py

import streamlit as st
import pandas as pd
import re
import base64

st.set_page_config(layout='wide')

def load_data(file):
    if file is not None:
        return pd.read_csv(file)
    else:
        return pd.DataFrame(columns=['context', 'question', 'answer'])

def download_csv(dataframe):
    csv = dataframe.to_csv(index=False)
    b64 = base64.b64encode(csv.encode()).decode()  
    href = f'<a href="data:file/csv;base64,{b64}" download="checked_data.csv">Download CSV File</a>'
    st.markdown(href, unsafe_allow_html=True)

uploaded_file = st.file_uploader("Upload CSV file", type=['csv'])

df = load_data(uploaded_file)

if 'idx' not in st.session_state:
    st.session_state.idx = 0

st.markdown("<h1 style='text-align: center;'>Investigation Legal Documents Dataset Checker</h1>", unsafe_allow_html=True)

col_1, col_2, col_3, col_4, col_5, col_6, col_7, col_8, col_9, col_10 = st.columns([1, 1, 1, 1, 1, 1, 1, 1, 1, 1])
btn_prev = col_1.button(label='Previous sample', use_container_width=True)
btn_next = col_2.button(label='Next sample', use_container_width=True)
btn_save = col_3.button(label='Save changes', use_container_width=True)
btn_download = col_4.button(label='Download CSV', use_container_width=True)

if btn_prev:
    if st.session_state.idx > 0:
        st.session_state.idx -= 1

if btn_next:
    if st.session_state.idx < len(df) - 1:
        st.session_state.idx += 1

st.markdown(f"<h3 style='text-align: center;'>Sample: {st.session_state.idx+1}/{len(df)}</h3>", unsafe_allow_html=True)

if not df.empty:
    context = st.text_area(label='Your context: ', value=df['context'][st.session_state.idx], height=300)
    question = st.text_area(label='Your question: ', value=df['question'][st.session_state.idx], height=100)
    answer = st.text_area(label='Your answer: ', value=df['answer'][st.session_state.idx], height=100)

    if answer.strip() and context.strip():
        highlighted_context = re.sub(re.escape(answer), "<mark>" + answer + "</mark>", context, flags=re.IGNORECASE)
        st.markdown(highlighted_context, unsafe_allow_html=True)

    if btn_save:
        df.loc[st.session_state.idx, 'context'] = context
        df.loc[st.session_state.idx, 'question'] = question
        df.loc[st.session_state.idx, 'answer'] = answer

        if uploaded_file is not None:
            uploaded_file.seek(0)
            df.to_csv(uploaded_file, index=False)

if btn_download:
    download_csv(df)