from sqlalchemy.ext.asyncio import create_async_engine, AsyncSession, async_sessionmaker
from sqlalchemy.orm import declarative_base, sessionmaker
from sqlalchemy import Column, Integer, String, DateTime, Boolean, Text
import os

Base = declarative_base()

DATABASE_URL = os.getenv("DATABASE_PATH", "data/schedule.db")
# SQLite через aiosqlite требует sqlite+aiosqlite:///
DATABASE_URL_ASYNC = f"sqlite+aiosqlite:///{DATABASE_URL}"

engine = create_async_engine(DATABASE_URL_ASYNC, echo=False)
AsyncSessionLocal = async_sessionmaker(engine, class_=AsyncSession, expire_on_commit=False)


class Task(Base):
    __tablename__ = "tasks"
    
    id = Column(Integer, primary_key=True, index=True)
    date = Column(String, index=True)  # YYYY-MM-DD
    title = Column(String, nullable=False)
    repeat_weekly = Column(Boolean, default=False)
    weekday = Column(Integer)  # 0=Monday, 6=Sunday, только для weekly tasks


class Event(Base):
    __tablename__ = "events"
    
    id = Column(Integer, primary_key=True, index=True)
    date = Column(String, index=True)  # YYYY-MM-DD
    start_time = Column(String)  # HH:MM
    duration_min = Column(Integer, nullable=False)
    title = Column(String, nullable=False)


class WeeklyTaskException(Base):
    __tablename__ = "weekly_task_exceptions"
    
    id = Column(Integer, primary_key=True, index=True)
    weekday = Column(Integer, nullable=False)  # 0=Monday, 6=Sunday
    date = Column(String, nullable=False)  # YYYY-MM-DD
    action = Column(String, nullable=False)  # "delete" или "replace"
    replacement_title = Column(String)  # для action="replace"


class TelegramUser(Base):
    __tablename__ = "telegram_users"
    
    id = Column(Integer, primary_key=True, index=True)
    chat_id = Column(String, unique=True, nullable=False, index=True)


async def init_db():
    async with engine.begin() as conn:
        await conn.run_sync(Base.metadata.create_all)


async def get_db():
    async with AsyncSessionLocal() as session:
        try:
            yield session
        finally:
            await session.close()