"""note_link_previews (URL unfurl — M6 1901)

Revision ID: 0020
Revises: 0019
Create Date: 2026-07-23

Cached OG/meta previews for URLs in a note, fetched server-side on request
(unfurl.py) and stored so they never re-fetch. One per (note, url).
"""
from alembic import op
import sqlalchemy as sa
from sqlalchemy.dialects.postgresql import UUID

revision = "0020"
down_revision = "0019"
branch_labels = None
depends_on = None


def upgrade() -> None:
    op.create_table(
        "note_link_previews",
        sa.Column("id", UUID(as_uuid=True), primary_key=True),
        sa.Column("note_id", UUID(as_uuid=True), sa.ForeignKey("notes.id", ondelete="CASCADE"), nullable=False),
        sa.Column("url", sa.Text(), nullable=False),
        sa.Column("title", sa.Text(), nullable=True),
        sa.Column("description", sa.Text(), nullable=True),
        sa.Column("image_url", sa.Text(), nullable=True),
        sa.Column("site_name", sa.Text(), nullable=True),
        sa.Column("created_at", sa.DateTime(timezone=True), nullable=False, server_default=sa.func.now()),
        sa.UniqueConstraint("note_id", "url", name="uq_note_link_previews_note_url"),
    )
    op.create_index("ix_note_link_previews_note", "note_link_previews", ["note_id"])


def downgrade() -> None:
    op.drop_index("ix_note_link_previews_note", table_name="note_link_previews")
    op.drop_table("note_link_previews")