from aiogram import Router, F
from aiogram.filters import Command
from aiogram.types import Message, CallbackQuery, InlineKeyboardMarkup, InlineKeyboardButton
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.vocabulary_service import VocabularyService
from services.ai_service import ai_service
from utils.i18n import t, get_user_lang

router = Router()


class AddWordStates(StatesGroup):
    """Состояния для добавления слова"""
    waiting_for_confirmation = State()
    waiting_for_word = State()


@router.message(Command("add"))
async def cmd_add(message: Message, state: FSMContext):
    """Обработчик команды /add [слово]"""
    # Получаем слово из команды
    parts = message.text.split(maxsplit=1)

    if len(parts) < 2:
        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, 'add.prompt'))
        await state.set_state(AddWordStates.waiting_for_word)
        return

    word = parts[1].strip()
    await process_word_addition(message, state, word)


@router.message(AddWordStates.waiting_for_word)
async def process_word_input(message: Message, state: FSMContext):
    """Обработка ввода слова"""
    word = message.text.strip()
    await process_word_addition(message, state, word)


async def process_word_addition(message: Message, state: FSMContext, word: str):
    """Обработка добавления слова"""
    # Получаем пользователя
    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

        # Проверяем, есть ли уже такое слово
        existing_word = await VocabularyService.find_word(session, user.id, word)
        if existing_word:
            lang = get_user_lang(user)
            await message.answer(t(lang, 'add.exists', word=word, translation=existing_word.word_translation))
            await state.clear()
            return

    # Показываем индикатор загрузки
    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'
    processing_msg = await message.answer(t(lang, 'add.searching'))

    # Получаем перевод через AI
    async with async_session_maker() as session:
        user = await UserService.get_user_by_telegram_id(session, message.from_user.id)
    source_lang = user.learning_language if user else 'en'
    ui_lang = user.language_interface if user else 'ru'
    word_data = await ai_service.translate_word(word, source_lang=source_lang, translation_lang=ui_lang)

    # Удаляем сообщение о загрузке
    await processing_msg.delete()

    # Формируем примеры
    examples_text = ""
    if word_data.get("examples"):
        examples_text = "\n\n" + t(lang, 'add.examples_header') + "\n"
        for idx, example in enumerate(word_data["examples"][:2], 1):
            src = example.get(source_lang) or example.get('en') or example.get('ru') or ''
            tr = example.get(ui_lang) or example.get('ru') or example.get('en') or ''
            examples_text += f"{idx}. {src}\n   <i>{tr}</i>\n"

    # Отправляем карточку слова
    card_text = (
        f"📝 <b>{word_data['word']}</b>\n"
        f"🔊 [{word_data.get('transcription', '')}]\n\n"
        f"{t(lang, 'add.translation_label')}: {word_data['translation']}\n"
        f"{t(lang, 'add.category_label')}: {word_data.get('category', '')}\n"
        f"{t(lang, 'add.level_label')}: {word_data.get('difficulty', 'A1')}"
        f"{examples_text}\n\n"
        f"{t(lang, 'add.confirm_question')}"
    )

    # Создаём inline-кнопки
    keyboard = InlineKeyboardMarkup(inline_keyboard=[
        [
            InlineKeyboardButton(text=t(lang, 'add.btn_add'), callback_data=f"add_word_confirm"),
            InlineKeyboardButton(text=t(lang, 'add.btn_cancel'), callback_data="add_word_cancel")
        ]
    ])

    # Сохраняем данные слова в состоянии
    await state.update_data(word_data=word_data, user_id=user.id)
    await state.set_state(AddWordStates.waiting_for_confirmation)

    await message.answer(card_text, reply_markup=keyboard)


@router.callback_query(F.data == "add_word_confirm", AddWordStates.waiting_for_confirmation)
async def confirm_add_word(callback: CallbackQuery, state: FSMContext):
    """Подтверждение добавления слова"""
    # Отвечаем сразу, запись в БД и подсчёт могут занять время
    await callback.answer()
    data = await state.get_data()
    word_data = data.get("word_data")
    user_id = data.get("user_id")

    async with async_session_maker() as session:
        # Получаем пользователя для языков
        user = await UserService.get_user_by_telegram_id(session, callback.from_user.id)
        source_lang = user.learning_language if user else 'en'
        ui_lang = user.language_interface if user else 'ru'

        # Добавляем слово в базу
        await VocabularyService.add_word(
            session,
            user_id=user_id,
            word_original=word_data["word"],
            word_translation=word_data["translation"],
            source_lang=source_lang,
            translation_lang=ui_lang,
            transcription=word_data.get("transcription"),
            examples={"examples": word_data.get("examples", [])},
            category=word_data.get("category"),
            difficulty_level=word_data.get("difficulty"),
            source=WordSource.MANUAL
        )

        # Получаем общее количество слов
        words_count = await VocabularyService.get_words_count(session, user_id, learning_lang=user.learning_language)
        lang = ui_lang or 'ru'

    await callback.message.edit_text(
        t(lang, 'add.added_success', word=word_data['word'], count=words_count)
    )

    await state.clear()


@router.callback_query(F.data == "add_word_cancel")
async def cancel_add_word(callback: CallbackQuery, state: FSMContext):
    """Отмена добавления слова"""
    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.edit_text(t(lang, 'add.cancelled'))
    await state.clear()
    await callback.answer()


WORDS_PER_PAGE = 10


@router.message(Command("vocabulary"))
async def cmd_vocabulary(message: Message):
    """Обработчик команды /vocabulary"""
    await show_vocabulary_page(message, page=0)


async def show_vocabulary_page(message_or_callback, page: int = 0, edit: bool = False):
    """Показать страницу словаря"""
    # Определяем, это Message или CallbackQuery
    # В CallbackQuery from_user — это пользователь, а message.from_user — бот
    user_id = message_or_callback.from_user.id

    async with async_session_maker() as session:
        user = await UserService.get_user_by_telegram_id(session, user_id)

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

        # Получаем слова с пагинацией
        offset = page * WORDS_PER_PAGE
        words = await VocabularyService.get_user_words(
            session, user.id,
            limit=WORDS_PER_PAGE,
            offset=offset,
            learning_lang=user.learning_language
        )
        total_count = await VocabularyService.get_words_count(session, user.id, learning_lang=user.learning_language)

        lang = get_user_lang(user)

        if not words and page == 0:
            if edit:
                await message_or_callback.message.edit_text(t(lang, 'vocab.empty'))
            else:
                await message_or_callback.answer(t(lang, 'vocab.empty'))
            return

        # Формируем список слов
        total_pages = (total_count + WORDS_PER_PAGE - 1) // WORDS_PER_PAGE
        words_list = t(lang, 'vocab.header') + "\n\n"

        for idx, word in enumerate(words, start=offset + 1):
            progress = ""
            if word.times_reviewed > 0:
                accuracy = int((word.correct_answers / word.times_reviewed) * 100)
                progress = " " + t(lang, 'vocab.accuracy_inline', n=accuracy)

            words_list += (
                f"{idx}. <b>{word.word_original}</b> — {word.word_translation}\n"
                f"   🔊 [{word.transcription or ''}]{progress}\n\n"
            )

        words_list += t(lang, 'vocab.page_info', page=page + 1, total=total_pages, count=total_count)

        # Кнопки пагинации
        buttons = []
        nav_row = []

        if page > 0:
            nav_row.append(InlineKeyboardButton(text="⬅️", callback_data=f"vocab_page_{page - 1}"))

        nav_row.append(InlineKeyboardButton(text=f"{page + 1}/{total_pages}", callback_data="vocab_noop"))

        if page < total_pages - 1:
            nav_row.append(InlineKeyboardButton(text="➡️", callback_data=f"vocab_page_{page + 1}"))

        if nav_row:
            buttons.append(nav_row)

        buttons.append([InlineKeyboardButton(text=t(lang, 'vocab.close_btn'), callback_data="vocab_close")])

        keyboard = InlineKeyboardMarkup(inline_keyboard=buttons)

        if edit:
            await message_or_callback.message.edit_text(words_list, reply_markup=keyboard)
        else:
            await message_or_callback.answer(words_list, reply_markup=keyboard)


@router.callback_query(F.data.startswith("vocab_page_"))
async def vocab_page_callback(callback: CallbackQuery):
    """Переключение страницы словаря"""
    page = int(callback.data.split("_")[-1])
    await callback.answer()
    await show_vocabulary_page(callback, page=page, edit=True)


@router.callback_query(F.data == "vocab_noop")
async def vocab_noop_callback(callback: CallbackQuery):
    """Пустой callback для кнопки с номером страницы"""
    await callback.answer()


@router.callback_query(F.data == "vocab_close")
async def vocab_close_callback(callback: CallbackQuery):
    """Закрыть словарь"""
    await callback.message.delete()
    await callback.answer()