database.py

from sqlalchemy import create_engine, Column, Integer, String, Text, ForeignKey, DateTime
from sqlalchemy.orm import declarative_base, sessionmaker, relationship
from datetime import datetime

# Cria engine SQLite
engine = create_engine("sqlite:///chatbot.db", echo=True)

# Base para os modelos
Base = declarative_base()

# Sessão
SessionLocal = sessionmaker(bind=engine, autoflush=False, autocommit=False)


class Chat(Base):
    __tablename__ = "chats"

    id = Column(Integer, primary_key=True, index=True)
    chat_id = Column(String, unique=True, index=True)  # mesmo que usamos no frontend
    created_at = Column(DateTime, default=datetime.utcnow)

    messages = relationship("Message", back_populates="chat")
    uploads = relationship("Upload", back_populates="chat")


class Message(Base):
    __tablename__ = "messages"

    id = Column(Integer, primary_key=True, index=True)
    role = Column(String)  # "user" ou "assistant"
    content = Column(Text)

    chat_id = Column(Integer, ForeignKey("chats.id"))
    chat = relationship("Chat", back_populates="messages")


class Upload(Base):
    __tablename__ = "uploads"

    id = Column(Integer, primary_key=True, index=True)
    filename = Column(String)
    content = Column(Text)

    chat_id = Column(Integer, ForeignKey("chats.id"))
    chat = relationship("Chat", back_populates="uploads")


# Cria tabelas
def init_db():
    Base.metadata.create_all(bind=engine)