import os
import streamlit as st
from st_aggrid import AgGrid
import pandas as pd
from transformers import pipeline, T5ForConditionalGeneration, T5Tokenizer
import plotly.express as px

# Set the page layout for Streamlit
st.set_page_config(layout="wide")

# Initialize TAPAS pipeline
tqa = pipeline(task="table-question-answering", 
              model="google/tapas-large-finetuned-wtq",
              device="cpu")

# Initialize T5 tokenizer and model for text generation
t5_tokenizer = T5Tokenizer.from_pretrained("t5-small")
t5_model = T5ForConditionalGeneration.from_pretrained("t5-small")

# Title and Introduction
st.title("Table Question Answering and Data Analysis App")
st.markdown(""" 
    This app allows you to upload a table (CSV or Excel) and ask questions about the data.
    Based on your question, it will provide the corresponding answer using the **TAPAS** model and additional data processing.

    ### Available Features:
    - **mean()**: For "average", it computes the mean of the entire numeric DataFrame.
    - **sum()**: For "sum", it calculates the sum of all numeric values in the DataFrame.
    - **max()**: For "max", it computes the maximum value in the DataFrame.
    - **min()**: For "min", it computes the minimum value in the DataFrame.
    - **count()**: For "count", it counts the non-null values in the entire DataFrame.
    - **Graph Generation**: You can ask questions like "make a graph of column sales?" or "make a graph between sales and expenses?". The app will generate interactive graphs for you.
    
    Upload your data and ask questions to get both answers and visualizations.
""")

# File uploader in the sidebar
file_name = st.sidebar.file_uploader("Upload file:", type=['csv', 'xlsx'])

# File processing and question answering
if file_name is None:
    st.markdown('<p class="font">Please upload an excel or csv file </p>', unsafe_allow_html=True)
else:
    try:
        # Check file type and handle reading accordingly
        if file_name.name.endswith('.csv'):
            df = pd.read_csv(file_name, sep=';', encoding='ISO-8859-1')  # Adjust encoding if needed
        elif file_name.name.endswith('.xlsx'):
            df = pd.read_excel(file_name, engine='openpyxl')  # Use openpyxl to read .xlsx files
        else:
            st.error("Unsupported file type")
            df = None

        if df is not None:
            numeric_columns = df.select_dtypes(include=['object']).columns
            for col in numeric_columns:
                df[col] = pd.to_numeric(df[col], errors='ignore')

            st.write("Original Data:")
            st.write(df)

            df_numeric = df.copy()
            df = df.astype(str)

            # Display the first 5 rows of the dataframe in an editable grid
            grid_response = AgGrid(
                df.head(5),
                fit_columns_on_grid_load=True,  # Correct parameter to fit columns on grid load
                editable=True, 
                height=300, 
                width='100%',
            )
            
    except Exception as e:
        st.error(f"Error reading file: {str(e)}")

    # User input for the question
    question = st.text_input('Type your question')

    # Check if the question is about generating a graph
    is_graph_query = False

    if 'graph' in question.lower():
        is_graph_query = True

    # Process the answer using TAPAS and T5
    with st.spinner():
        if st.button('Answer'):
            try:
                if not is_graph_query:
                    # Process TAPAS-related questions if it's not a graph query
                    raw_answer = tqa(table=df, query=question, truncation=True)

                    # Display raw answer from TAPAS on the screen
                    st.markdown("<p style='font-family:sans-serif;font-size: 1rem;'>Raw TAPAS Answer: </p>", unsafe_allow_html=True)
                    st.write(raw_answer)  # Display the raw TAPAS output

                    # Extract relevant values for Plotly
                    answer = raw_answer.get('answer', '')
                    coordinates = raw_answer.get('coordinates', [])
                    cells = raw_answer.get('cells', [])

                    st.markdown("<p style='font-family:sans-serif;font-size: 1rem;'>Relevant Data for Plotly: </p>", unsafe_allow_html=True)
                    st.write(f"Answer: {answer}")
                    st.write(f"Coordinates: {coordinates}")
                    st.write(f"Cells: {cells}")

                    # If TAPAS is returning a list of numbers for "average" like you mentioned
                    if "average" in question.lower() and cells:
                        # Assuming cells are numeric values that can be plotted in a graph
                        plot_data = [float(cell) for cell in cells]  # Convert cells to numeric data

                        # Create a DataFrame for Plotly
                        plot_df = pd.DataFrame({ 'Index': list(range(1, len(plot_data) + 1)), 'Value': plot_data })

                        # Generate a graph using Plotly
                        fig = px.line(plot_df, x='Index', y='Value', title=f"Graph for '{question}'")
                        st.plotly_chart(fig, use_container_width=True)

                    else:
                        st.write(f"No data to plot for the question: '{question}'")

                else:
                    # Handle graph-related questions
                    if 'between' in question.lower() and 'and' in question.lower():
                        columns = question.split('between')[-1].split('and')
                        columns = [col.strip() for col in columns]
                        if len(columns) == 2 and all(col in df.columns for col in columns):
                            fig = px.scatter(df, x=columns[0], y=columns[1], title=f"Graph between {columns[0]} and {columns[1]}")
                            st.plotly_chart(fig, use_container_width=True)
                            st.success(f"Here is the graph between '{columns[0]}' and '{columns[1]}'.")
                        else:
                            st.warning("Columns not found in the dataset.")
                    elif 'column' in question.lower():
                        column = question.split('of')[-1].strip()
                        if column in df.columns:
                            fig = px.line(df, x=df.index, y=column, title=f"Graph of column '{column}'")
                            st.plotly_chart(fig, use_container_width=True)
                    
                    st.stop()  # This halts further execution

            except Exception as e:
                st.warning(f"Error processing question or generating answer: {str(e)}")
                st.warning("Please retype your question and make sure to use the column name and cell value correctly.")