import { Knex } from "knex";

export default async (knex: Knex): Promise<void> => {
  const addColumn = async (table: string, column: string, type: string) => {
    if (!(await knex.schema.hasTable(table))) return;
    if (!(await knex.schema.hasColumn(table, column))) {
      await knex.schema.alterTable(table, (t) => (t as any)[type](column));
    }
  };

  const dropColumn = async (table: string, column: string) => {
    if (!(await knex.schema.hasTable(table))) return;
    if (await knex.schema.hasColumn(table, column)) {
      await knex.schema.alterTable(table, (t) => t.dropColumn(column));
    }
  };

  const alterColumnType = async (table: string, column: string, type: string) => {
    if (!(await knex.schema.hasTable(table))) return;
    if (await knex.schema.hasColumn(table, column)) {
      await knex.schema.alterTable(table, (t) => {
        (t as any)[type](column).alter();
      });
    }
  };
};