"""An explored channel someone follows is the catalog's own, and so are its videos

Revision ID: 0116_followed_explored_channels
Revises: 0115_takeout_channels
Create Date: 2026-10-24

A follow pulled in from YouTube (the subscription import) left an explored channel flagged as an
exploration's, and a subscribe landing while an exploration's videos came in left those videos
flagged on a channel that no longer was one. Both are held in the code now; this clears what they
left: the channel of a subscription is not an exploration's, and no video is an exploration's on a
channel that is not one. Data only, so the downgrade has nothing to undo.
"""

from alembic import op

revision: str = "0116_followed_explored_channels"
down_revision: str | None = "0115_takeout_channels"
branch_labels: str | None = None
depends_on: str | None = None


def upgrade() -> None:
    op.execute(
        "UPDATE channels SET from_explore = false WHERE from_explore"
        " AND EXISTS (SELECT 1 FROM subscriptions s WHERE s.channel_id = channels.id)"
    )
    op.execute(
        "UPDATE videos SET via_explore = false WHERE via_explore"
        " AND channel_id IN (SELECT id FROM channels WHERE NOT from_explore)"
    )


def downgrade() -> None:
    pass