import uuid
from sqlalchemy import Column, String, Text, Integer, BigInteger, Boolean, DateTime, ForeignKey, Index
from sqlalchemy.orm import relationship
from sqlalchemy.sql import func
from app.core.database import Base


class Attachment(Base):
    __tablename__ = "pjctrl_attachments"

    id = Column(String(36), primary_key=True, default=lambda: str(uuid.uuid4()))
    task_id = Column(String(36), ForeignKey("pjctrl_tasks.id", ondelete="CASCADE"), nullable=False)
    filename = Column(String(255), nullable=False)
    original_filename = Column(String(255), nullable=False)
    mime_type = Column(String(100), nullable=False)
    file_size = Column(BigInteger, nullable=False)
    current_version = Column(Integer, default=1, nullable=False)
    is_encrypted = Column(Boolean, default=False, nullable=False)
    uploaded_by = Column(String(36), ForeignKey("pjctrl_users.id", ondelete="SET NULL"), nullable=True)
    is_deleted = Column(Boolean, default=False, nullable=False)
    created_at = Column(DateTime, server_default=func.now(), nullable=False)
    updated_at = Column(DateTime, server_default=func.now(), onupdate=func.now(), nullable=False)

    # Relationships
    task = relationship("Task", back_populates="attachments")
    uploader = relationship("User", foreign_keys=[uploaded_by])
    versions = relationship("AttachmentVersion", back_populates="attachment", cascade="all, delete-orphan")

    __table_args__ = (
        Index("idx_attachment_task", "task_id", "is_deleted"),
    )