"""Add appversions.sha256 and appversions.silentargs (installer delivery metadata)

The endpoint installer push resolves a specific AppVersion: sha256 pins the
exact bytes the agent must fetch, and silentargs carries this version's
unattended-install switches (homegrown EXEs vary by developer; MSI is uniform
via msiexec). Both nullable. Idempotent guards and real downgrade.

Revision ID: 7d35_appversion_delivery_metadata
Revises: 7d34_singular_relationship_types
Create Date: 2026-07-24

"""
from alembic import op
import sqlalchemy as sa


revision = '7d35_appversion_delivery_metadata'
down_revision = '7d34_singular_relationship_types'
branch_labels = None
depends_on = None


def _has_col(insp, name):
    return any(c['name'] == name for c in insp.get_columns('appversions'))


def upgrade():
    bind = op.get_bind()
    insp = sa.inspect(bind)
    if 'appversions' not in insp.get_table_names():
        return
    if not _has_col(insp, 'sha256'):
        op.add_column('appversions', sa.Column('sha256', sa.String(length=64), nullable=True))
    if not _has_col(insp, 'silentargs'):
        op.add_column('appversions', sa.Column('silentargs', sa.String(length=255), nullable=True))


def downgrade():
    bind = op.get_bind()
    insp = sa.inspect(bind)
    if 'appversions' not in insp.get_table_names():
        return
    if _has_col(insp, 'silentargs'):
        op.drop_column('appversions', 'silentargs')
    if _has_col(insp, 'sha256'):
        op.drop_column('appversions', 'sha256')