from datetime import datetime
from typing import Optional

from sqlalchemy import String, BigInteger, DateTime, Integer, Boolean, JSON, Enum as SQLEnum, UniqueConstraint
from sqlalchemy.orm import DeclarativeBase, Mapped, mapped_column
import enum


class Base(DeclarativeBase):
    """Базовая модель"""
    pass


class LanguageLevel(str, enum.Enum):
    """Уровни владения языком"""
    A1 = "A1"
    A2 = "A2"
    B1 = "B1"
    B2 = "B2"
    C1 = "C1"
    C2 = "C2"


class WordSource(str, enum.Enum):
    """Источник добавления слова"""
    MANUAL = "manual"  # Ручное добавление
    SUGGESTED = "suggested"  # Предложено ботом
    CONTEXT = "context"  # Из контекста диалога
    IMPORT = "import"  # Импорт из текста
    ERROR = "error"  # Из ошибок в заданиях


class User(Base):
    """Модель пользователя"""
    __tablename__ = "users"

    id: Mapped[int] = mapped_column(primary_key=True)
    telegram_id: Mapped[int] = mapped_column(BigInteger, unique=True, nullable=False)
    username: Mapped[Optional[str]] = mapped_column(String(255))
    language_interface: Mapped[str] = mapped_column(String(2), default="ru")  # ru/en
    learning_language: Mapped[str] = mapped_column(String(2), default="en")  # en
    level: Mapped[LanguageLevel] = mapped_column(SQLEnum(LanguageLevel), default=LanguageLevel.A1)
    timezone: Mapped[str] = mapped_column(String(50), default="UTC")
    daily_task_time: Mapped[Optional[str]] = mapped_column(String(5))  # HH:MM
    reminders_enabled: Mapped[bool] = mapped_column(Boolean, default=False)
    last_reminder_sent: Mapped[Optional[datetime]] = mapped_column(DateTime)
    streak_days: Mapped[int] = mapped_column(Integer, default=0)
    created_at: Mapped[datetime] = mapped_column(DateTime, default=datetime.utcnow)
    last_active: Mapped[datetime] = mapped_column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)


class Vocabulary(Base):
    """Модель словарного запаса"""
    __tablename__ = "vocabulary"
    __table_args__ = (
        UniqueConstraint("user_id", "source_lang", "word_original", name="uq_vocab_user_lang_word"),
    )

    id: Mapped[int] = mapped_column(primary_key=True)
    user_id: Mapped[int] = mapped_column(Integer, nullable=False, index=True)
    word_original: Mapped[str] = mapped_column(String(255), nullable=False)
    word_translation: Mapped[str] = mapped_column(String(255), nullable=False)
    source_lang: Mapped[Optional[str]] = mapped_column(String(5))  # ISO2 языка слова (язык изучения)
    translation_lang: Mapped[Optional[str]] = mapped_column(String(5))  # ISO2 языка перевода (обычно язык интерфейса)
    transcription: Mapped[Optional[str]] = mapped_column(String(255))
    examples: Mapped[Optional[dict]] = mapped_column(JSON)  # JSON массив примеров
    category: Mapped[Optional[str]] = mapped_column(String(100))
    difficulty_level: Mapped[Optional[LanguageLevel]] = mapped_column(SQLEnum(LanguageLevel))
    source: Mapped[WordSource] = mapped_column(SQLEnum(WordSource), default=WordSource.MANUAL)
    times_reviewed: Mapped[int] = mapped_column(Integer, default=0)
    correct_answers: Mapped[int] = mapped_column(Integer, default=0)
    last_reviewed: Mapped[Optional[datetime]] = mapped_column(DateTime)
    created_at: Mapped[datetime] = mapped_column(DateTime, default=datetime.utcnow)
    notes: Mapped[Optional[str]] = mapped_column(String(500))  # Заметки пользователя


class Task(Base):
    """Модель задания"""
    __tablename__ = "tasks"

    id: Mapped[int] = mapped_column(primary_key=True)
    user_id: Mapped[int] = mapped_column(Integer, nullable=False, index=True)
    task_type: Mapped[str] = mapped_column(String(50), nullable=False)  # translate, sentence, fill, etc.
    content: Mapped[dict] = mapped_column(JSON, nullable=False)  # Содержание задания
    correct_answer: Mapped[Optional[str]] = mapped_column(String(500))
    user_answer: Mapped[Optional[str]] = mapped_column(String(500))
    is_correct: Mapped[Optional[bool]] = mapped_column(Boolean)
    ai_feedback: Mapped[Optional[str]] = mapped_column(String(1000))
    completed_at: Mapped[Optional[datetime]] = mapped_column(DateTime)
    created_at: Mapped[datetime] = mapped_column(DateTime, default=datetime.utcnow)