app.py

import streamlit as st
import importlib
from fpdf import FPDF
import uuid

# 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",
}

# Module descriptions
module_descriptions = {
    "Bases": "This module covers the presentation of numbers in various bases, including binary, octal, decimal, and hexadecimal.",
    "Validity": "This module helps determine the validity of numbers in different bases.",
    "Conversion": "This module covers conversion techniques between different bases, including with and without fractions.",
    "Grouping": "This module focuses on grouping techniques for conversion between bases such as binary and hexadecimal.",
    "Addition": "This module covers addition operations in bases like binary, octal, and hexadecimal.",
    "2's Complement": "This module explains the 2's complement method for representing negative numbers.",
    "Negative Numbers": "This module covers negative binary numbers and their representation.",
    "Subtraction": "This module focuses on subtraction operations in binary using the 2's complement method.",
}

# Initialize unique session state
if 'session_id' not in st.session_state:
    st.session_state.session_id = str(uuid.uuid4())

# Initialize session state variables
if 'questions' not in st.session_state:
    st.session_state.questions = []
if 'current_index' not in st.session_state:
    st.session_state.current_index = 0
if 'current_module' not in st.session_state:
    st.session_state.current_module = None
if 'correct_count' not in st.session_state:
    st.session_state.correct_count = 0
if 'module_correct_count' not in st.session_state:
    st.session_state.module_correct_count = {name: 0 for name in module_names}
if 'module_question_count' not in st.session_state:
    st.session_state.module_question_count = {name: 0 for name in module_names}
if 'pdf_data' not in st.session_state:
    st.session_state.pdf_data = None

def reset_pdf_cache():
    st.session_state.pdf_data = 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 module in module_names.keys():
        pdf.set_text_color(0, 0, 0)
        pdf.cell(200, 10, txt=f"Module: {module}", ln=True, align="L")
        pdf.ln(5)
        correct_count = st.session_state.module_correct_count[module]
        total_count = st.session_state.module_question_count[module]
        pdf.cell(200, 10, txt=f"Correct Answers: {correct_count}/{total_count}", ln=True, align="L")
        pdf.ln(5)

        for entry in st.session_state.questions:
            if entry['module'] == module:
                question, options, selected, correct, explanation, step_by_step_solution = (
                    entry['question'], 
                    entry['options'], 
                    entry['selected'] if entry['selected'] is not None else "Not Answered",
                    entry['correct_answer'], 
                    entry['explanation'],
                    entry['step_by_step_solution']
                )
                pdf.multi_cell(0, 10, f"Q: {question}")
                for option in options:
                    if option == correct:
                        pdf.set_text_color(0, 128, 0)  # Green for correct
                        pdf.multi_cell(0, 10, f"{option}")
                    elif option == selected:
                        pdf.set_text_color(255, 0, 0)  # Red for incorrect
                        pdf.multi_cell(0, 10, f"{option}")
                    else:
                        pdf.set_text_color(0, 0, 0)  # Default color for others
                        pdf.multi_cell(0, 10, f"   {option}")
                pdf.set_text_color(0, 0, 0)  # Reset color
                pdf.multi_cell(0, 10, f"Explanation: {explanation}")
                pdf.ln(5)
                pdf.multi_cell(0, 10, "Step-by-Step Solution:")
                for step in step_by_step_solution:
                    pdf.multi_cell(0, 10, step)
                pdf.ln(10)

        pdf.ln(10)  # Add space after each module

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

def load_module(module_name):
    module_file = module_names[module_name]
    module = importlib.import_module(f'modules.{module_file}')
    return module

def generate_new_question(module_name):
    module = load_module(module_name)
    question_data = module.generate_question()
    # Ensure 'answered' is initialized to False and add the 'module' and 'selected' keys
    question_data['answered'] = False
    question_data['module'] = module_name  # Add the module name to the question data
    question_data['selected'] = None  # Initialize 'selected' to None
    # Ensure there are 5 options
    if len(question_data['options']) != 5:
        st.warning(f"Question does not have 5 options. Found {len(question_data['options'])}.")
    return question_data

def navigate_question(direction):
    if direction == "prev" and st.session_state.current_index > 0:
        st.session_state.current_index -= 1
    elif direction == "next":
        if st.session_state.current_index < len(st.session_state.questions) - 1:
            st.session_state.current_index += 1
        else:
            # Generate a new question if at the end of the list
            new_question = generate_new_question(st.session_state.current_module)
            st.session_state.questions.append(new_question)
            st.session_state.current_index += 1

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

if module_name != st.session_state.current_module:
    st.session_state.current_module = module_name
    st.session_state.current_index = 0
    st.session_state.questions = [generate_new_question(module_name)]

# Load the current module's question
if st.session_state.current_index < len(st.session_state.questions):
    current_question = st.session_state.questions[st.session_state.current_index]
else:
    current_question = generate_new_question(st.session_state.current_module)
    st.session_state.questions.append(current_question)
    st.session_state.current_index = len(st.session_state.questions) - 1

# Display module title and description
st.title(module_name)
st.write(module_descriptions.get(module_name, "No description available for this module."))
st.write(current_question["question"])

# Use a form to prevent rerun on option selection
with st.form(key=f'question_form_{st.session_state.current_index}'):
    selected_answer = st.radio(
        "Choose an answer:", 
        options=current_question['options'], 
        key=f"question_{st.session_state.current_index}_options",
        index=None  # No pre-selection
    )
    submit_button = st.form_submit_button(label="Submit")

if submit_button and not current_question.get('answered', False):
    if selected_answer is None:
        st.warning("Please select an answer before submitting.")
    else:
        # Process the answer
        current_question['selected'] = selected_answer
        current_question['answered'] = True
        st.session_state.module_question_count[module_name] += 1

        if selected_answer == current_question['correct_answer']:
            st.session_state.correct_count += 1
            st.session_state.module_correct_count[module_name] += 1

# Show correct/incorrect feedback after submission
if current_question.get('answered', False):
    for option in current_question['options']:
        if option == current_question['correct_answer']:
            st.markdown(f"<span style='color:green;'>{option} ✅</span>", unsafe_allow_html=True)
        elif option == current_question['selected']:
            st.markdown(f"<span style='color:red;'>{option} ❌</span>", unsafe_allow_html=True)
        else:
            st.markdown(f"{option}")
    
    # Show explanation and step-by-step solution
    st.write(f"**Explanation:** {current_question['explanation']}")
    st.write("**Step-by-Step Solution:**")
    for step in current_question['step_by_step_solution']:
        st.write(step)

# Navigation buttons (placed after question and options)
col1, col2 = st.columns([1, 1])
with col1:
    if st.button("⬅️ Prev", key=f'prev_button_{st.session_state.current_index}', disabled=st.session_state.current_index == 0):
        navigate_question("prev")

with col2:
    if st.button("➡️ Next", key=f'next_button_{st.session_state.current_index}'):
        navigate_question("next")

# PDF Download Button (at the bottom)
if len(st.session_state.questions) > 0:
    pdf = generate_pdf_report()
    st.session_state.pdf_data = pdf  # Reset PDF cache
    st.download_button(
        label="Download PDF Report 📄",
        data=st.session_state.pdf_data,
        file_name="quiz_report.pdf",
        mime="application/pdf"
    )