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

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

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 = {}
if 'module_question_count' not in st.session_state:
    st.session_state.module_question_count = {}
if 'pdf_data' not in st.session_state:
    st.session_state.pdf_data = None
if 'selected_answer' not in st.session_state:
    st.session_state.selected_answer = None
if 'button_label' not in st.session_state:
    st.session_state.button_label = "Submit/New"

def reset_pdf_cache():
    st.session_state.pdf_data = None

def generate_pdf_report():
    pdf = FPDF()
    pdf.add_page()
    pdf.set_font("Arial", size=10)
    
    pdf.cell(200, 10, txt="Quiz Report", ln=True, align="C")
    pdf.ln(10)

    for i, entry in enumerate(st.session_state.questions):
        # Zebra background
        if i % 2 == 0:
            pdf.set_fill_color(245, 245, 245)  # Light gray
        else:
            pdf.set_fill_color(255, 255, 255)  # White

        # Module Title
        pdf.set_font("Arial", style='B', size=10)
        pdf.multi_cell(0, 10, f"Module: {entry['module']}", border=1, fill=True)

        # Question
        pdf.set_font("Arial", style='B', size=10)
        pdf.multi_cell(0, 10, f"Q{i+1}: {entry['question']}", border=1, fill=True)
        
        # Options
        pdf.set_font("Arial", size=10)
        options = ['a', 'b', 'c', 'd']
        for j, option in enumerate(entry['options']):
            if option == entry['correct_answer']:
                pdf.set_text_color(0, 128, 0)  # Green for correct
            elif option == entry['selected']:
                pdf.set_text_color(255, 0, 0)  # Red for incorrect
            else:
                pdf.set_text_color(0, 0, 0)  # Default color for others

            pdf.multi_cell(0, 10, f"{options[j]}. {option}", border=1, fill=True)
        
        pdf.set_text_color(0, 0, 0)  # Reset color
        pdf.multi_cell(0, 10, f"Explanation: {entry['explanation']}", border=1, fill=True)
        pdf.multi_cell(0, 10, f"Step-by-Step Solution: {', '.join(entry['step_by_step_solution'])}", border=1, fill=True)
        pdf.ln(10)

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

def load_modules():
    modules = {}
    module_dir = "modules"
    for filename in os.listdir(module_dir):
        if filename.endswith(".py") and filename != "__init__.py":
            module_name = filename[:-3]
            # Dynamically import the module only when needed
            module = __import__(f"{module_dir}.{module_name}", fromlist=[''])
            modules[module_name] = {
                "title": getattr(module, "title", module_name),
                "description": getattr(module, "description", "No description available."),
                "generate_question": module.generate_question  # Access the generate_question function
            }
    return modules

def generate_new_question(module_name, module):
    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 exactly 4 options
    if len(question_data['options']) != 4:
        st.warning(f"Question in module '{module_name}' does not have 4 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" and st.session_state.current_index < len(st.session_state.questions) - 1:
        st.session_state.current_index += 1

# Load all modules dynamically
modules = load_modules()

# Streamlit interface
st.sidebar.title("Quiz Modules")
module_name = st.sidebar.radio("Choose a module:", [modules[module]["title"] for module in modules], index=0)

selected_module = None
for module in modules:
    if modules[module]["title"] == module_name:
        selected_module = module
        break

if selected_module != st.session_state.current_module:
    st.session_state.current_module = selected_module
    st.session_state.current_index = len(st.session_state.questions)  # Continue numbering from previous questions
    st.session_state.questions.append(generate_new_question(selected_module, modules[selected_module]))
    st.session_state.module_question_count[selected_module] = st.session_state.module_question_count.get(selected_module, 0)
    st.session_state.module_correct_count[selected_module] = st.session_state.module_correct_count.get(selected_module, 0)
    st.session_state.selected_answer = None
    st.session_state.button_label = "Submit/New"

# Load the current module's question
current_question = st.session_state.questions[st.session_state.current_index]

# Display module title and description with smaller header and font
st.markdown(f"### {modules[selected_module]['title']}")
st.markdown(f"<span style='font-size: 12px;'>{modules[selected_module]['description']}</span>", unsafe_allow_html=True)

# Navigation and PDF report buttons
col1, col2, col3 = st.columns([1, 1, 2])
with col1:
    if st.button("⬅️ Prev", disabled=st.session_state.current_index == 0):
        navigate_question("prev")
with col2:
    if st.button("➡️ Next", disabled=st.session_state.current_index >= len(st.session_state.questions) - 1):
        navigate_question("next")
with col3:
    if any(q['answered'] for q in st.session_state.questions):
        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"
        )

# Display the current question with larger font
st.markdown(f"<span style='font-size: 18px;'><b>Q{st.session_state.current_index + 1}: {current_question['question']}</b></span>", unsafe_allow_html=True)

# Create the form for the question
with st.form(key=f'question_form_{st.session_state.current_index}'):
    options = ['a', 'b', 'c', 'd']
    selected_answer = st.radio(
        "Choose an answer:", 
        options=[f"{options[i]}. {opt}" for i, opt in enumerate(current_question['options'])], 
        key=f"question_{st.session_state.current_index}_options",
        index=None if not current_question['answered'] else current_question['options'].index(current_question['selected']),
        disabled=current_question['answered']
    )
    
    submit_button = st.form_submit_button(label="Submit/New", disabled=current_question['answered'])

# Handle button state and answer submission
if submit_button:
    if selected_answer is None:
        st.warning("Please select an option before submitting.", icon="⚠️")
    else:
        # Process the answer
        selected_answer_text = selected_answer.split(". ", 1)[1]  # Extract the text part
        current_question['selected'] = selected_answer_text
        current_question['answered'] = True
        st.session_state.module_question_count[selected_module] += 1

        if selected_answer_text == current_question['correct_answer']:
            st.session_state.correct_count += 1
            st.session_state.module_correct_count[selected_module] += 1

        # Show correct/incorrect feedback, explanation, and step-by-step solution
        st.markdown(
            """
            <div style='background-color:#f0f0f0; padding: 10px; border-radius: 10px;'>
            """, unsafe_allow_html=True)
        for i, option in enumerate(current_question['options']):
            option_text = f"{options[i]}. {option}"
            if option == current_question['correct_answer']:
                st.markdown(f"<span style='color:green;'>{option_text} ✅</span>", unsafe_allow_html=True)
            elif option == selected_answer_text:
                st.markdown(f"<span style='color:red;'>{option_text} ❌</span>", unsafe_allow_html=True)
            else:
                st.markdown(f"{option_text}", unsafe_allow_html=True)
        
        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)
        st.markdown("</div>", unsafe_allow_html=True)

        # Generate a new question after submission
        new_question = generate_new_question(selected_module, modules[selected_module])
        st.session_state.questions.append(new_question)
        st.session_state.current_index = len(st.session_state.questions) - 1