from sqlalchemy import Column, String, Integer, BigInteger, Boolean, DateTime, ForeignKey, Text, CheckConstraint, Index
from sqlalchemy.sql import func
from datetime import datetime
from app.core.database.db_session import Base

class FileUpload(Base):
    __tablename__ = "file_uploads"

    file_id = Column(String(26), primary_key=True)
    original_name = Column(String(255), nullable=False)
    stored_name = Column(String(100), nullable=True)
    mime_type = Column(String(100), nullable=False)
    extension = Column(String(10), nullable=True)
    file_size = Column(BigInteger, nullable=False)
    storage_provider = Column(String(30), nullable=False, default="LOCAL")

    # Path variants
    raw_path = Column(String(500), nullable=True)
    webp_path = Column(String(500), nullable=True)
    thumbnail_path = Column(String(500), nullable=True)
    medium_path = Column(String(500), nullable=True)
    large_path = Column(String(500), nullable=True)
    storage_path = Column(String(500), nullable=True)  # Legacy fallback compatibility

    entity_type = Column(String(50), nullable=True)
    entity_id = Column(String(50), nullable=True)
    blur_hash = Column(String(255), nullable=True)

    # State machine status
    status = Column(
        String(30),
        CheckConstraint("status IN ('ACTIVE', 'ORPHANED', 'PENDING_DELETE', 'DELETED', 'INCONSISTENT')"),
        nullable=False,
        default="ACTIVE",
        server_default="ACTIVE"
    )

    # Lifecycle audit timestamps & tracking
    orphaned_at = Column(DateTime, nullable=True)
    cleanup_claimed_at = Column(DateTime, nullable=True)
    cleanup_started_at = Column(DateTime, nullable=True)
    deleted_at = Column(DateTime, nullable=True)
    last_reconciled_at = Column(DateTime, nullable=True)

    cleanup_attempts = Column(Integer, nullable=False, default=0)
    last_cleanup_error = Column(Text, nullable=True)

    uploaded_by = Column(String(26), ForeignKey("users.user_id", ondelete="SET NULL"), nullable=True)
    created_at = Column(DateTime, server_default=func.now())
    updated_at = Column(DateTime, server_default=func.now(), onupdate=func.now())

    __table_args__ = (
        Index("idx_file_uploads_status_orphaned", "status", "orphaned_at"),
    )