"""extend_flow_proposals_l1

Revision ID: ff6fe5895ea2
Revises: a8186f22506d
Create Date: 2026-05-28 16:26:06.932886

"""
from typing import Sequence, Union

from alembic import op
import sqlalchemy as sa


# revision identifiers, used by Alembic.
revision: str = 'ff6fe5895ea2'
down_revision: Union[str, None] = 'a8186f22506d'
branch_labels: Union[str, Sequence[str], None] = None
depends_on: Union[str, Sequence[str], None] = None


def upgrade() -> None:
    op.add_column('flow_proposals', sa.Column('source', sa.String(30), nullable=True))
    op.add_column('flow_proposals', sa.Column('linked_ticket_id', sa.String(64), nullable=True))
    op.add_column('flow_proposals', sa.Column('linked_ticket_kind', sa.String(10), nullable=True))
    op.add_column(
        'flow_proposals',
        sa.Column('validated_by_outcome', sa.Boolean(), nullable=False, server_default='false'),
    )

    # Backfill existing rows then enforce NOT NULL on source
    op.execute("UPDATE flow_proposals SET source = 'manual_draft' WHERE source IS NULL")
    op.alter_column('flow_proposals', 'source', nullable=False)

    op.create_check_constraint(
        'ck_flow_proposals_source',
        'flow_proposals',
        "source IN ('ai_realtime_l1', 'kb_accelerator', 'manual_draft', 'ai_promoted')",
    )
    op.create_check_constraint(
        'ck_flow_proposals_linked_ticket_kind',
        'flow_proposals',
        "linked_ticket_kind IS NULL OR linked_ticket_kind IN ('psa', 'internal')",
    )


def downgrade() -> None:
    op.drop_constraint('ck_flow_proposals_linked_ticket_kind', 'flow_proposals', type_='check')
    op.drop_constraint('ck_flow_proposals_source', 'flow_proposals', type_='check')
    op.drop_column('flow_proposals', 'validated_by_outcome')
    op.drop_column('flow_proposals', 'linked_ticket_kind')
    op.drop_column('flow_proposals', 'linked_ticket_id')
    op.drop_column('flow_proposals', 'source')