app.py

import streamlit as st
import importlib
from fpdf import FPDF

# List of available modules with shorter names and icons
module_names = {
    "Bases": "presentation_bases",
    "Validity": "valid_invalid_numbers",
    "Conversion": "conversion_bases",
    "Grouping": "grouping_techniques",
    "Addition": "addition_bases",
    "2's Complement": "twos_complement",
    "Negative Numbers": "negative_binary",
    "Subtraction": "subtraction_bases",
}

# Initialize session state for tracking answers, progress, and questions queue
if 'correct_count' not in st.session_state:
    st.session_state.correct_count = 0
if 'question_count' not in st.session_state:
    st.session_state.question_count = 0
if 'current_module' not in st.session_state:
    st.session_state.current_module = None
if 'question_queue' not in st.session_state:
    st.session_state.question_queue = []
if 'submitted' not in st.session_state:
    st.session_state.submitted = False
if 'selected_answer' not in st.session_state:
    st.session_state.selected_answer = None

def generate_pdf_report():
    pdf = FPDF()
    pdf.add_page()
    pdf.set_font("Arial", size=12)

    pdf.cell(200, 10, txt="Quiz Report", ln=True, align="C")
    pdf.ln(10)

    for idx, entry in enumerate(st.session_state.question_queue):
        question, selected, correct, explanation = entry
        pdf.multi_cell(0, 10, f"Q{idx+1}: {question}")
        pdf.multi_cell(0, 10, f"Selected Answer: {selected}")
        pdf.multi_cell(0, 10, f"Correct Answer: {correct}")
        pdf.multi_cell(0, 10, f"Explanation: {explanation}")
        pdf.ln(10)

    return pdf.output(dest='S').encode('latin1')

# Streamlit interface
st.sidebar.title("Quiz Modules")
module_name = st.sidebar.radio("Choose a module:", list(module_names.keys()), index=0)

if module_name:
    module_file = module_names[module_name]
    try:
        module = importlib.import_module(f'modules.{module_file}')
        generate_question = module.generate_question
        title = getattr(module, 'title', f"{module_name} Module")
        description = getattr(module, 'description', "Description is not available")
        
        # Show module title and description
        st.title(title)
        st.write(description)

        if st.session_state.submitted:
            st.session_state.submitted = False
            st.session_state.question_count += 1
            st.session_state.question_queue.append((
                st.session_state.current_question, 
                st.session_state.selected_answer, 
                st.session_state.correct_answer, 
                st.session_state.explanation
            ))

            if st.session_state.selected_answer == st.session_state.correct_answer:
                st.session_state.correct_count += 1
                st.success("✅ Correct!")
            else:
                st.error("❌ Incorrect.")
            st.write(f"**Explanation:** {st.session_state.explanation}")

        if st.session_state.question_count > 0:
            correct_percentage = (st.session_state.correct_count / st.session_state.question_count) * 100
            st.write(f"**Correct Answers:** {st.session_state.correct_count}/{st.session_state.question_count} ({correct_percentage:.2f}%)")

        if not st.session_state.submitted:
            st.session_state.current_question, options, st.session_state.correct_answer, st.session_state.explanation = generate_question()
            st.write(f"**Question {st.session_state.question_count + 1}:** {st.session_state.current_question}")
            st.session_state.selected_answer = st.radio("Choose an answer:", options)

            col1, col2 = st.columns([1, 5])
            with col1:
                if st.button("⬅️ Prev"):
                    # Logic for previous question (if applicable)
                    pass
            with col2:
                if st.button("Submit"):
                    st.session_state.submitted = True
                    st.experimental_rerun()

        if st.session_state.submitted:
            col1, col2, col3 = st.columns([1, 1, 3])
            with col1:
                if st.button("⬅️ Prev"):
                    # Logic for previous question (if applicable)
                    pass
            with col2:
                if st.button("➡️ Next"):
                    st.experimental_rerun()
            with col3:
                if st.session_state.question_count > 0:
                    pdf = generate_pdf_report()
                    st.download_button(
                        label="Download PDF Report 📄",
                        data=pdf,
                        file_name="quiz_report.pdf",
                        mime="application/pdf"
                    )

    except ModuleNotFoundError:
        st.error(f"The module '{module_name}' was not found. Please select another module.")