import pandas as pd
import streamlit as st
import json

def load_table_config(file_path: str) -> dict:
    """Load the table configuration JSON."""
    with open(file_path, 'r') as f:
        return json.load(f)

def load_uploaded_files(uploaded_files):
    """
    Load dataframes from the uploaded files (CSV/Excel).
    Returns a list of pandas DataFrames.
    """
    dataframes = []
    for file in uploaded_files:
        if file.name.endswith('.csv'):
            df = pd.read_csv(file)
        else:
            df = pd.read_excel(file)
        dataframes.append(df)
    return dataframes

def display_table_descriptions(selected_tables, table_config):
    """
    Given a list of selected table names and the table config,
    write out their descriptions in the sidebar.
    """
    if selected_tables:
        st.sidebar.subheader("Table Descriptions")
        for table_name in selected_tables:
            description = table_config[table_name].get('description', "No description available.")
            cols = table_config[table_name].get('cols', [])
            st.sidebar.markdown(f"**{table_name}**: {description}")
            st.sidebar.markdown(f"**Available columns**: {cols}")