"""
Embedding model — stores CLIP/SigLIP image embeddings via pgvector.

Composite PK (photo_id, model) allows re-embedding with newer models
without clobbering old vectors.
"""
from sqlalchemy import Column, String, ForeignKey, DateTime, func
from pgvector.sqlalchemy import Vector

from app.database import Base


class Embedding(Base):
    __tablename__ = 'embeddings'

    photo_id = Column(String, ForeignKey('photos.id', ondelete='CASCADE'), primary_key=True)
    model = Column(String(64), primary_key=True)  # e.g. 'openclip_vitb32'
    vector = Column(Vector(512))                   # OpenCLIP ViT-B/32 → 512-d
    created_at = Column(DateTime(timezone=True), server_default=func.now())