import sqlite3
import streamlit as st
import random
import time
from datetime import datetime, timedelta

class QuizApp:
    def __init__(self):
        self.conn = sqlite3.connect('exam.db')
        self.cursor = self.conn.cursor()
        self.initialize_session_state()
    
    def fetch_questions(self, year, trial, paper_id):
        self.cursor.execute('''
            SELECT question_id, question, option_A, option_B, option_C, option_D, answer 
            FROM exam_questions
            WHERE year = ? AND trial = ? AND id = ?
        ''', (year, trial, paper_id))
        questions = self.cursor.fetchall()
        return questions

    def initialize_session_state(self):
        if 'questions' not in st.session_state:
            st.session_state['questions'] = []
        if 'user_answers' not in st.session_state:
            st.session_state['user_answers'] = {}
        if 'current_question_index' not in st.session_state:
            st.session_state['current_question_index'] = 0
        if 'start_time' not in st.session_state:
            st.session_state['start_time'] = time.time()
        if 'quiz_ended' not in st.session_state:
            st.session_state['quiz_ended'] = False
        if 'score' not in st.session_state:
            st.session_state['score'] = 0
        if 'wrong_answers' not in st.session_state:
            st.session_state['wrong_answers'] = []
        if 'quiz_started' not in st.session_state:
            st.session_state['quiz_started'] = False
        if 'end_time' not in st.session_state:
            st.session_state['end_time'] = datetime.now() + timedelta(minutes=120)
        if 'question_order' not in st.session_state:
            st.session_state['question_order'] = []

    def extract_image_url(self, question_text):
        img_tag_start = '<img src="'
        img_tag_end = '"'
        start_index = question_text.find(img_tag_start)
        if start_index != -1:
            end_index = question_text.find(img_tag_end, start_index+len(img_tag_start))
            if end_index != -1:
                return question_text[start_index+len(img_tag_start):end_index]
        return None

    def show_question(self, index):
        question_id, question, option_A, option_B, option_C, option_D, _ = st.session_state['questions'][index]
        options = ['A', 'B', 'C', 'D']
        options_text = [option_A, option_B, option_C, option_D]
        selected_option = st.session_state['user_answers'].get(question_id, None)
        
        image_url = self.extract_image_url(question)
        if image_url:
            question = question.replace(f'<img src="{image_url}" />', '')

        return question, options_text, options, selected_option, image_url

    def submit_answer(self, selected_option):
        question_id = st.session_state['questions'][st.session_state['current_question_index']][0]
        st.session_state['user_answers'][question_id] = selected_option

    def next_question(self):
        if st.session_state['current_question_index'] < len(st.session_state['questions'])-1:
            st.session_state['current_question_index']+=1
        else:
            self.end_quiz()

    def end_quiz(self):
        score = 0
        wrong_answers = []
        for question in st.session_state['questions']:
            question_id, _, _, _, _, _, correct_answer = question
            if str(st.session_state['user_answers'].get(question_id)) == correct_answer:
                score+=1
            else:
                wrong_answers.append((question_id, correct_answer))
        st.session_state['score'] = score
        st.session_state['wrong_answers'] = sorted(wrong_answers, key=lambda x: int(x[0]))
        st.session_state['quiz_ended'] = True

    def render_quiz(self):
        timer_placeholder = st.empty()
        
        if not st.session_state['quiz_ended']:
            question, options_text, options, selected_option, image_url = self.show_question(st.session_state['current_question_index'])

            st.write(f"{st.session_state['current_question_index']+1}. {question}")

            if image_url:
                st.image(image_url)

            # Ensure form submission logic is handled correctly
            with st.form(key="quiz_form"):
                selected_option_text = st.radio("Choose an option", options_text, index=options_text.index(selected_option) if selected_option else 0)
                submit_button = st.form_submit_button(label="Submit Answer")

                if submit_button:
                    selected_option = options[options_text.index(selected_option_text)]
                    print(selected_option, selected_option_text)
                    self.submit_answer(selected_option)
                    self.next_question()
                    st.experimental_rerun()

            st.button("End Quiz", on_click=self.end_quiz)

            # Dynamic countdown timer
            remaining_time = st.session_state['end_time'] - datetime.now()
            if remaining_time.total_seconds()>0:
                minutes, seconds = divmod(remaining_time.total_seconds(), 60)
                timer_placeholder.markdown(f"## 剩餘時間: {int(minutes):02d}:{int(seconds):02d}")
                time.sleep(1)
                st.experimental_rerun()
            else:
                self.end_quiz()

        else:
            st.write(f"Score: {st.session_state['score']}/{len(st.session_state['questions'])}")
            
            selected_id = st.selectbox("Select Question to View Details", range(1, len(st.session_state['questions'])+1))
            if selected_id-1 is not None:
                question = st.session_state['questions'][selected_id-1]
                st.write(f"試卷題號: {question[0]}")
                st.write(f"{question[1]}")
                st.write(f"A. {question[2]}")
                st.write(f"B. {question[3]}")
                st.write(f"C. {question[4]}")
                st.write(f"D. {question[5]}")
                st.write(f"答案: {question[6]}")

    def render(self):
        if not st.session_state['quiz_started']:
            st.title("考古題選擇")

            year = st.selectbox("年份", ['111', '112', '113'])
            trial = st.selectbox("場次", ("寒考", "暑考"))
            paper_id = st.selectbox("考卷", ("醫師（一）", "醫師（二）"))

            if st.button("Submit"):
                if trial == "寒考":
                    trial_q = 1
                else:
                    trial_q = 2
                if paper_id == "醫師（一）":
                    id_q = 1
                else:
                    id_q = 2
                st.session_state['questions'] = self.fetch_questions(year, trial_q, id_q)
                if st.session_state['questions']:
                    random.shuffle(st.session_state['questions'])
                    st.session_state['question_order'] = [q[0] for q in st.session_state['questions']]
                    st.session_state['quiz_started'] = True
                    st.session_state['end_time'] = datetime.now()+timedelta(minutes=120)
                    st.experimental_rerun()
                else:
                    st.write("找不到對應的考卷，請重新選擇。")
        else:
            self.render_quiz()

if __name__ == "__main__":
    app = QuizApp()
    app.render()