from aiogram import Router, F
from aiogram.filters import Command
from aiogram.types import Message, InlineKeyboardMarkup, InlineKeyboardButton, CallbackQuery
from aiogram.fsm.context import FSMContext
from aiogram.fsm.state import State, StatesGroup

from database.db import async_session_maker
from database.models import WordSource
from services.user_service import UserService
from services.task_service import TaskService
from services.vocabulary_service import VocabularyService
from services.ai_service import ai_service
from utils.i18n import t, get_user_lang
from utils.levels import get_user_level_for_language

router = Router()


class TaskStates(StatesGroup):
    """Состояния для прохождения заданий"""
    choosing_mode = State()
    doing_tasks = State()
    waiting_for_answer = State()


@router.message(Command("task"))
async def cmd_task(message: Message, state: FSMContext):
    """Обработчик команды /task — показываем меню выбора режима"""
    async with async_session_maker() as session:
        user = await UserService.get_user_by_telegram_id(session, message.from_user.id)

        if not user:
            await message.answer(t('ru', 'common.start_first'))
            return

        lang = get_user_lang(user)

        keyboard = InlineKeyboardMarkup(inline_keyboard=[
            [InlineKeyboardButton(
                text=t(lang, 'tasks.mode_vocabulary'),
                callback_data="task_mode_vocabulary"
            )],
            [InlineKeyboardButton(
                text=t(lang, 'tasks.mode_new_words'),
                callback_data="task_mode_new"
            )]
        ])

        await state.update_data(user_id=user.id)
        await state.set_state(TaskStates.choosing_mode)
        await message.answer(t(lang, 'tasks.choose_mode'), reply_markup=keyboard)


@router.callback_query(F.data == "task_mode_vocabulary", TaskStates.choosing_mode)
async def start_vocabulary_tasks(callback: CallbackQuery, state: FSMContext):
    """Начать задания по словам из словаря"""
    await callback.answer()

    async with async_session_maker() as session:
        user = await UserService.get_user_by_telegram_id(session, callback.from_user.id)

        if not user:
            await callback.message.edit_text(t('ru', 'common.start_first'))
            return

        lang = get_user_lang(user)

        # Генерируем задания по словам из словаря
        tasks = await TaskService.generate_mixed_tasks(
            session, user.id, count=5,
            learning_lang=user.learning_language,
            translation_lang=user.language_interface,
        )

        if not tasks:
            await callback.message.edit_text(t(lang, 'tasks.no_words'))
            await state.clear()
            return

        # Сохраняем задания в состоянии
        await state.update_data(
            tasks=tasks,
            current_task_index=0,
            correct_count=0,
            user_id=user.id,
            mode='vocabulary'
        )
        await state.set_state(TaskStates.doing_tasks)

        await callback.message.delete()
        await show_current_task(callback.message, state)


@router.callback_query(F.data == "task_mode_new", TaskStates.choosing_mode)
async def start_new_words_tasks(callback: CallbackQuery, state: FSMContext):
    """Начать задания с новыми словами"""
    await callback.answer()

    async with async_session_maker() as session:
        user = await UserService.get_user_by_telegram_id(session, callback.from_user.id)

        if not user:
            await callback.message.edit_text(t('ru', 'common.start_first'))
            return

        lang = get_user_lang(user)
        level = get_user_level_for_language(user)

        # Показываем индикатор загрузки
        await callback.message.edit_text(t(lang, 'tasks.generating_new'))

        # Получаем слова для исключения:
        # 1. Все слова из словаря пользователя
        vocab_words = await VocabularyService.get_all_user_word_strings(
            session, user.id, learning_lang=user.learning_language
        )
        # 2. Слова из предыдущих заданий new_words, на которые ответили правильно
        correct_task_words = await TaskService.get_correctly_answered_words(
            session, user.id
        )
        # Объединяем списки исключений
        exclude_words = list(set(vocab_words + correct_task_words))

        # Генерируем новые слова через AI
        words = await ai_service.generate_thematic_words(
            theme="random everyday vocabulary",
            level=level,
            count=5,
            learning_lang=user.learning_language,
            translation_lang=user.language_interface,
            exclude_words=exclude_words if exclude_words else None,
        )

        if not words:
            await callback.message.edit_text(t(lang, 'tasks.generate_failed'))
            await state.clear()
            return

        # Преобразуем слова в задания
        tasks = []
        translate_prompt = t(lang, 'tasks.translate_to', lang_name=t(lang, f'lang.{user.language_interface}'))
        for word in words:
            tasks.append({
                'type': 'translate',
                'question': f"{translate_prompt}: {word.get('word', '')}",
                'word': word.get('word', ''),
                'correct_answer': word.get('translation', ''),
                'transcription': word.get('transcription', ''),
                'example': word.get('example', ''),  # Пример на изучаемом языке
                'example_translation': word.get('example_translation', '')  # Перевод примера
            })

        await state.update_data(
            tasks=tasks,
            current_task_index=0,
            correct_count=0,
            user_id=user.id,
            mode='new_words'
        )
        await state.set_state(TaskStates.doing_tasks)

        await callback.message.delete()
        await show_current_task(callback.message, state)


async def show_current_task(message: Message, state: FSMContext):
    """Показать текущее задание"""
    data = await state.get_data()
    tasks = data.get('tasks', [])
    current_index = data.get('current_task_index', 0)

    if current_index >= len(tasks):
        # Все задания выполнены
        await finish_tasks(message, state)
        return

    task = tasks[current_index]

    # Определяем язык пользователя
    async with async_session_maker() as session:
        user = await UserService.get_user_by_telegram_id(session, message.from_user.id)
    lang = (user.language_interface if user else 'ru') or 'ru'

    task_text = (
        t(lang, 'tasks.header', i=current_index + 1, n=len(tasks)) + "\n\n" +
        f"{task['question']}\n"
    )

    if task.get('transcription'):
        task_text += f"🔊 [{task['transcription']}]\n"

    task_text += t(lang, 'tasks.write_answer')

    await state.set_state(TaskStates.waiting_for_answer)
    await message.answer(task_text)


@router.message(TaskStates.waiting_for_answer)
async def process_answer(message: Message, state: FSMContext):
    """Обработка ответа пользователя"""
    user_answer = message.text.strip()
    data = await state.get_data()

    tasks = data.get('tasks', [])
    current_index = data.get('current_task_index', 0)
    correct_count = data.get('correct_count', 0)
    user_id = data.get('user_id')

    task = tasks[current_index]

    # Показываем индикатор проверки
    # Язык пользователя
    async with async_session_maker() as session:
        user = await UserService.get_user_by_telegram_id(session, message.from_user.id)
    lang = (user.language_interface if user else 'ru') or 'ru'

    checking_msg = await message.answer(t(lang, 'tasks.checking'))

    # Проверяем ответ через AI
    check_result = await ai_service.check_answer(
        question=task['question'],
        correct_answer=task['correct_answer'],
        user_answer=user_answer
    )

    await checking_msg.delete()

    is_correct = check_result.get('is_correct', False)
    feedback = check_result.get('feedback', '')

    # Формируем ответ
    if is_correct:
        result_text = t(lang, 'tasks.correct') + "\n\n"
        correct_count += 1
    else:
        result_text = t(lang, 'tasks.incorrect') + "\n\n"

    result_text += f"{t(lang, 'tasks.your_answer')}: <i>{user_answer}</i>\n"
    result_text += f"{t(lang, 'tasks.right_answer')}: <b>{task['correct_answer']}</b>\n\n"

    if feedback:
        result_text += f"💬 {feedback}\n\n"

    # Показываем пример использования если есть
    example = task.get('example', '')
    example_translation = task.get('example_translation', '')
    if example:
        result_text += f"📖 {t(lang, 'tasks.example_label')}:\n"
        result_text += f"<i>{example}</i>\n"
        if example_translation:
            result_text += f"<i>({example_translation})</i>\n"
        result_text += "\n"

    # Сохраняем результат в БД
    async with async_session_maker() as session:
        await TaskService.save_task_result(
            session=session,
            user_id=user_id,
            task_type=task['type'],
            content={
                'question': task['question'],
                'word': task['word']
            },
            user_answer=user_answer,
            correct_answer=task['correct_answer'],
            is_correct=is_correct,
            ai_feedback=feedback
        )

        # Обновляем статистику слова
        if 'word_id' in task:
            await TaskService.update_word_statistics(
                session=session,
                word_id=task['word_id'],
                is_correct=is_correct
            )

    # Обновляем счетчик
    await state.update_data(
        current_task_index=current_index + 1,
        correct_count=correct_count
    )

    # Показываем результат и кнопку "Далее"
    mode = data.get('mode')
    buttons = [[InlineKeyboardButton(text=t(lang, 'tasks.next_btn'), callback_data="next_task")]]

    # Для режима new_words добавляем кнопку "Добавить слово"
    if mode == 'new_words':
        buttons.append([InlineKeyboardButton(
            text=t(lang, 'tasks.add_word_btn'),
            callback_data=f"add_task_word_{current_index}"
        )])

    buttons.append([InlineKeyboardButton(text=t(lang, 'tasks.stop_btn'), callback_data="stop_tasks")])
    keyboard = InlineKeyboardMarkup(inline_keyboard=buttons)

    await message.answer(result_text, reply_markup=keyboard)
    # После показа результата ждём нажатия кнопки – переключаемся в состояние doing_tasks
    await state.set_state(TaskStates.doing_tasks)


@router.callback_query(F.data == "next_task", TaskStates.doing_tasks)
async def next_task(callback: CallbackQuery, state: FSMContext):
    """Переход к следующему заданию"""
    await callback.message.delete()
    await show_current_task(callback.message, state)
    await callback.answer()


@router.callback_query(F.data.startswith("add_task_word_"), TaskStates.doing_tasks)
async def add_task_word(callback: CallbackQuery, state: FSMContext):
    """Добавить слово из задания в словарь"""
    task_index = int(callback.data.split("_")[-1])
    data = await state.get_data()
    tasks = data.get('tasks', [])

    if task_index >= len(tasks):
        await callback.answer()
        return

    task = tasks[task_index]
    word = task.get('word', '')
    translation = task.get('correct_answer', '')
    transcription = task.get('transcription', '')
    example = task.get('example', '')  # Пример использования как контекст
    example_translation = task.get('example_translation', '')  # Перевод примера

    async with async_session_maker() as session:
        user = await UserService.get_user_by_telegram_id(session, callback.from_user.id)

        if not user:
            await callback.answer()
            return

        lang = get_user_lang(user)

        # Проверяем, есть ли слово уже в словаре
        existing = await VocabularyService.get_word_by_original(session, user.id, word)

        if existing:
            await callback.answer(t(lang, 'tasks.word_already_exists', word=word), show_alert=True)
            return

        # Добавляем слово в словарь
        new_word = await VocabularyService.add_word(
            session=session,
            user_id=user.id,
            word_original=word,
            word_translation=translation,
            source_lang=user.learning_language,
            translation_lang=user.language_interface,
            transcription=transcription,
            source=WordSource.AI_TASK
        )

        # Сохраняем перевод в таблицу word_translations
        await VocabularyService.add_translations_bulk(
            session=session,
            vocabulary_id=new_word.id,
            translations=[{
                'translation': translation,
                'context': example if example else None,
                'context_translation': example_translation if example_translation else None,
                'is_primary': True
            }]
        )

    await callback.answer(t(lang, 'tasks.word_added', word=word), show_alert=True)


@router.callback_query(F.data == "stop_tasks", TaskStates.doing_tasks)
async def stop_tasks_callback(callback: CallbackQuery, state: FSMContext):
    """Остановить выполнение заданий через кнопку"""
    await state.clear()
    await callback.message.edit_reply_markup(reply_markup=None)
    async with async_session_maker() as session:
        user = await UserService.get_user_by_telegram_id(session, callback.from_user.id)
    lang = (user.language_interface if user else 'ru') or 'ru'
    await callback.message.answer(t(lang, 'tasks.finished'))
    await callback.answer()


@router.message(Command("stop"), TaskStates.doing_tasks)
@router.message(Command("stop"), TaskStates.waiting_for_answer)
async def stop_tasks(message: Message, state: FSMContext):
    """Остановить выполнение заданий командой /stop"""
    await state.clear()
    # Определяем язык пользователя
    async with async_session_maker() as session:
        user = await UserService.get_user_by_telegram_id(session, message.from_user.id)
    await message.answer(t((user.language_interface if user else 'ru') or 'ru', 'tasks.stopped'))


@router.message(Command("cancel"), TaskStates.doing_tasks)
@router.message(Command("cancel"), TaskStates.waiting_for_answer)
async def cancel_tasks(message: Message, state: FSMContext):
    """Отмена выполнения заданий командой /cancel"""
    await state.clear()
    async with async_session_maker() as session:
        user = await UserService.get_user_by_telegram_id(session, message.from_user.id)
    lang = (user.language_interface if user else 'ru') or 'ru'
    await message.answer(t(lang, 'tasks.cancelled'))


async def finish_tasks(message: Message, state: FSMContext):
    """Завершение всех заданий"""
    data = await state.get_data()
    tasks = data.get('tasks', [])
    correct_count = data.get('correct_count', 0)
    total_count = len(tasks)

    accuracy = int((correct_count / total_count) * 100) if total_count > 0 else 0

    # Определяем эмодзи на основе результата
    if accuracy >= 90:
        emoji = "🏆"
        comment_key = 'excellent'
    elif accuracy >= 70:
        emoji = "👍"
        comment_key = 'good'
    elif accuracy >= 50:
        emoji = "📚"
        comment_key = 'average'
    else:
        emoji = "💪"
        comment_key = 'poor'

    # Язык пользователя
    async with async_session_maker() as session:
        user = await UserService.get_user_by_telegram_id(session, message.from_user.id)
    lang = (user.language_interface if user else 'ru') or 'ru'

    result_text = (
        t(lang, 'tasks.finish_title', emoji=emoji) + "\n\n" +
        t(lang, 'tasks.correct_of', correct=correct_count, total=total_count) + "\n" +
        t(lang, 'tasks.accuracy', accuracy=accuracy) + "\n\n" +
        t(lang, f"tasks.comment.{comment_key}") + "\n\n" +
        t(lang, 'tasks.use_task') + "\n" +
        t(lang, 'tasks.use_stats')
    )

    await state.clear()
    await message.answer(result_text)


@router.message(Command("stats"))
async def cmd_stats(message: Message):
    """Обработчик команды /stats"""
    async with async_session_maker() as session:
        user = await UserService.get_user_by_telegram_id(session, message.from_user.id)

        if not user:
            await message.answer(t('ru', 'common.start_first'))
            return

        # Получаем статистику
        stats = await TaskService.get_user_stats(session, user.id)
        lang = (user.language_interface if user else 'ru') or 'ru'

        stats_text = (
            t(lang, 'stats.header') + "\n\n" +
            t(lang, 'stats.total_words', n=stats['total_words']) + "\n" +
            t(lang, 'stats.studied_words', n=stats['reviewed_words']) + "\n" +
            t(lang, 'stats.total_tasks', n=stats['total_tasks']) + "\n" +
            t(lang, 'stats.correct_tasks', n=stats['correct_tasks']) + "\n" +
            t(lang, 'stats.accuracy', n=stats['accuracy']) + "\n\n"
        )

        if stats['total_words'] == 0:
            stats_text += t(lang, 'stats.hint_add_words')
        elif stats['total_tasks'] == 0:
            stats_text += t(lang, 'stats.hint_first_task')
        else:
            stats_text += t(lang, 'stats.hint_keep_practice')

        await message.answer(stats_text)