import os
import streamlit as st
from st_aggrid import AgGrid
import pandas as pd
from transformers import pipeline, T5ForConditionalGeneration, T5Tokenizer

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

# CSS styling
# ... (keep your existing CSS code)

# 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("HERTOG-AI 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.
    
    You can upload your data and ask questions like "What is the average of column X?" or "What is the sum of column Y?". The app will automatically process the data and give you the relevant answer.
""")


# 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),
                columns_auto_size_mode='FIT_CONTENTS',
                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')

    # Process the answer using TAPAS and T5
    with st.spinner():
        if st.button('Answer'):
            try:
                raw_answer = tqa(table=df, query=question, truncation=True)
                
                st.markdown("<p style='font-family:sans-serif;font-size: 0.9rem;'> Raw Result From TAPAS: </p>",
                           unsafe_allow_html=True)
                st.success(raw_answer)
                
                answer = raw_answer['answer']
                aggregator = raw_answer.get('aggregator', '')
                coordinates = raw_answer.get('coordinates', [])
                cells = raw_answer.get('cells', [])
                
                # Check if the answer contains non-numeric values, and filter them out
                numeric_cells = []
                for cell in cells:
                    try:
                        numeric_cells.append(float(cell))  # Convert to float if possible
                    except ValueError:
                        pass  # Ignore non-numeric cells

                # Handle aggregation based on user question or TAPAS output
                if 'average' in question.lower() or aggregator == 'AVG':
                    if numeric_cells:
                        avg_value = sum(numeric_cells) / len(numeric_cells)  # Calculate average
                        base_sentence = f"The average for '{question}' is {avg_value:.2f}."
                    else:
                        base_sentence = f"No numeric data found for calculating the average of '{question}'."
                elif 'sum' in question.lower() or aggregator == 'SUM':
                    if numeric_cells:
                        total_sum = sum(numeric_cells)  # Calculate sum
                        base_sentence = f"The sum for '{question}' is {total_sum:.2f}."
                    else:
                        base_sentence = f"No numeric data found for calculating the sum of '{question}'."
                elif 'max' in question.lower() or aggregator == 'MAX':
                    if numeric_cells:
                        max_value = max(numeric_cells)  # Find max value
                        base_sentence = f"The maximum value for '{question}' is {max_value:.2f}."
                    else:
                        base_sentence = f"No numeric data found for finding the maximum value of '{question}'."
                elif 'min' in question.lower() or aggregator == 'MIN':
                    if numeric_cells:
                        min_value = min(numeric_cells)  # Find min value
                        base_sentence = f"The minimum value for '{question}' is {min_value:.2f}."
                    else:
                        base_sentence = f"No numeric data found for finding the minimum value of '{question}'."
                elif 'count' in question.lower() or aggregator == 'COUNT':
                    count_value = len(numeric_cells)  # Count numeric cells
                    base_sentence = f"The total count of numeric values for '{question}' is {count_value}."
                else:
                    # Construct a base sentence for other aggregators or no aggregation
                    base_sentence = f"The answer from TAPAS for '{question}' is {answer}."
                    if coordinates and cells:
                        rows_info = [f"Row {coordinate[0] + 1}, Column '{df.columns[coordinate[1]]}' with value {cell}" 
                                     for coordinate, cell in zip(coordinates, cells)]
                        rows_description = " and ".join(rows_info)
                        base_sentence += f" This includes the following data: {rows_description}."

                # Generate a fluent response using the T5 model, rephrasing the base sentence
                input_text = f"Given the question: '{question}', generate a more human-readable response: {base_sentence}"

                # Tokenize the input and generate a fluent response using T5
                inputs = t5_tokenizer.encode(input_text, return_tensors="pt", max_length=512, truncation=True)
                summary_ids = t5_model.generate(inputs, max_length=150, num_beams=4, early_stopping=True)

                # Decode the generated text
                generated_text = t5_tokenizer.decode(summary_ids[0], skip_special_tokens=True)

                # Display the final generated response
                st.markdown("<p style='font-family:sans-serif;font-size: 0.9rem;'> Final Generated Response with LLM: </p>", unsafe_allow_html=True)
                st.success(generated_text)

            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.")