from sqlalchemy import (
  Column, String, Boolean, DateTime, Integer,
  Text, BigInteger, Index
)
from sqlalchemy.sql import func
from .base import Base

class GeneratedFile(Base):
  __tablename__ = "generated_files"
  
  id = Column(Integer, primary_key=True)
  file_id = Column(String(36), unique=True, nullable=False, index=True)
  user_hash = Column(String(64), nullable=False, index=True)
  tenant_id = Column(String(64), nullable=True, index=True)
  
  file_name = Column(String(300), nullable=False)
  file_type = Column(String(20))
  # xlsx | pdf | docx | csv | ps1 | sh
  
  file_size_bytes = Column(BigInteger, default=0)
  storage_path = Column(String(500))
  
  # Context
  generated_for = Column(String(100))
  # "P&L May 2026" | "Payroll June 2026"
  
  chat_session_id = Column(String(36), nullable=True, index=True)
  project_id = Column(String(36), nullable=True, index=True)
  
  # Formula version used
  formula_version = Column(String(50))
  
  # Downloads
  download_count = Column(Integer, default=0)
  last_downloaded_at = Column(DateTime, nullable=True)
  
  # Retention
  expires_at = Column(DateTime, nullable=True)
  is_deleted = Column(Boolean, default=False)
  
  created_at = Column(DateTime, server_default=func.now())
  
  __table_args__ = (
    Index("ix_files_user", "user_hash"),
    Index("ix_files_session", "chat_session_id"),
    Index("ix_files_project", "project_id"),
    Index("ix_files_created", "created_at"),
  )