"""add operation log audit fields

Revision ID: add_operation_log_audit_fields
Revises: shift_all_timestamps_to_beijing
Create Date: 2026-03-11
"""

from __future__ import annotations

from alembic import op
import sqlalchemy as sa


revision = "add_operation_log_audit_fields"
down_revision = "shift_all_timestamps_to_beijing"
branch_labels = None
depends_on = None


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(col.get("name") == column_name for col in inspector.get_columns(table_name))


def _index_exists(bind, table_name: str, index_name: str) -> bool:
    inspector = sa.inspect(bind)
    if not inspector.has_table(table_name):
        return False
    return any(idx.get("name") == index_name for idx in inspector.get_indexes(table_name))


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

    with op.batch_alter_table("operation_logs") as batch_op:
        if not _column_exists(bind, "operation_logs", "trace_id"):
            batch_op.add_column(sa.Column("trace_id", sa.String(length=64), nullable=True))
        if not _column_exists(bind, "operation_logs", "interface_path"):
            batch_op.add_column(sa.Column("interface_path", sa.String(length=255), nullable=True))
        if not _column_exists(bind, "operation_logs", "caller"):
            batch_op.add_column(
                sa.Column("caller", sa.String(length=16), nullable=False, server_default=sa.text("'system'"))
            )

    if not _index_exists(bind, "operation_logs", "ix_operation_logs_trace_id"):
        op.create_index("ix_operation_logs_trace_id", "operation_logs", ["trace_id"], unique=False)
    if not _index_exists(bind, "operation_logs", "ix_operation_logs_interface_path"):
        op.create_index("ix_operation_logs_interface_path", "operation_logs", ["interface_path"], unique=False)
    if not _index_exists(bind, "operation_logs", "ix_operation_logs_caller"):
        op.create_index("ix_operation_logs_caller", "operation_logs", ["caller"], unique=False)


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

    if _index_exists(bind, "operation_logs", "ix_operation_logs_caller"):
        op.drop_index("ix_operation_logs_caller", table_name="operation_logs")
    if _index_exists(bind, "operation_logs", "ix_operation_logs_interface_path"):
        op.drop_index("ix_operation_logs_interface_path", table_name="operation_logs")
    if _index_exists(bind, "operation_logs", "ix_operation_logs_trace_id"):
        op.drop_index("ix_operation_logs_trace_id", table_name="operation_logs")

    with op.batch_alter_table("operation_logs") as batch_op:
        if _column_exists(bind, "operation_logs", "caller"):
            batch_op.drop_column("caller")
        if _column_exists(bind, "operation_logs", "interface_path"):
            batch_op.drop_column("interface_path")
        if _column_exists(bind, "operation_logs", "trace_id"):
            batch_op.drop_column("trace_id")