"""add task breakdown payload fields

Revision ID: 20260326_add_task_breakdown_payload_fields
Revises: add_project_create_idempotency_indexes
Create Date: 2026-03-26
"""

from __future__ import annotations

from alembic import op
import sqlalchemy as sa

try:
    from sqlalchemy.dialects.postgresql import JSONB
except Exception:  # pragma: no cover
    JSONB = sa.JSON


revision = "20260326_add_task_breakdown_payload_fields"
down_revision = "add_project_create_idempotency_indexes"
branch_labels = None
depends_on = None


def _json_type(bind):
    return JSONB() if bind.dialect.name == "postgresql" else sa.JSON()


def _table_exists(bind, table_name: str) -> bool:
    return sa.inspect(bind).has_table(table_name)


def _column_exists(bind, table_name: str, column_name: str) -> bool:
    inspector = sa.inspect(bind)
    if not inspector.has_table(table_name):
        return False
    return any(str(item.get("name") or "") == column_name for item in inspector.get_columns(table_name))


def upgrade() -> None:
    bind = op.get_bind()
    table_name = "tasks"
    if not _table_exists(bind, table_name):
        return

    if not _column_exists(bind, table_name, "ai_breakdown_payload"):
        op.add_column(table_name, sa.Column("ai_breakdown_payload", _json_type(bind), nullable=True))
    if not _column_exists(bind, table_name, "manual_overrides"):
        op.add_column(table_name, sa.Column("manual_overrides", _json_type(bind), nullable=True))


def downgrade() -> None:
    bind = op.get_bind()
    table_name = "tasks"
    if not _table_exists(bind, table_name):
        return

    if _column_exists(bind, table_name, "manual_overrides"):
        op.drop_column(table_name, "manual_overrides")
    if _column_exists(bind, table_name, "ai_breakdown_payload"):
        op.drop_column(table_name, "ai_breakdown_payload")