import { MigrationInterface, QueryRunner } from "typeorm";

/**
 * CBE Unified Bill Payment (docs/cbe/CBE_IMPLEMENTATION_PLAN.md §4.1, §5):
 * - `bill_reference` — the short numeric Bill_Id CBE presents back to us; unique, null for
 *   every non-CBE intent.
 * - `payer_name` — payer snapshot captured at initiate; fallback for /cbe/query Full_Name.
 * - `cbe_bill_reference_seq` — backs the 11-digit sequence body of the bill reference.
 *
 * DATA SAFETY: purely additive — new nullable columns and a new sequence; no existing rows
 * or values are touched.
 */
export class AddCbeBillReference1782300000000 implements MigrationInterface {
  name = "AddCbeBillReference1782300000000";

  public async up(queryRunner: QueryRunner): Promise<void> {
    await queryRunner.query(
      `ALTER TABLE "edr_payment"."payment_intent" ADD COLUMN IF NOT EXISTS "bill_reference" varchar(32)`,
    );
    await queryRunner.query(
      `ALTER TABLE "edr_payment"."payment_intent" ADD COLUMN IF NOT EXISTS "payer_name" varchar(128)`,
    );
    await queryRunner.query(
      `CREATE UNIQUE INDEX IF NOT EXISTS "uq_payment_intent_bill_reference" ON "edr_payment"."payment_intent" ("bill_reference") WHERE "bill_reference" IS NOT NULL`,
    );
    await queryRunner.query(
      `CREATE SEQUENCE IF NOT EXISTS "edr_payment"."cbe_bill_reference_seq" START 10000001`,
    );
  }

  public async down(queryRunner: QueryRunner): Promise<void> {
    await queryRunner.query(
      `DROP SEQUENCE IF EXISTS "edr_payment"."cbe_bill_reference_seq"`,
    );
    await queryRunner.query(
      `DROP INDEX IF EXISTS "edr_payment"."uq_payment_intent_bill_reference"`,
    );
    await queryRunner.query(
      `ALTER TABLE "edr_payment"."payment_intent" DROP COLUMN IF EXISTS "payer_name"`,
    );
    await queryRunner.query(
      `ALTER TABLE "edr_payment"."payment_intent" DROP COLUMN IF EXISTS "bill_reference"`,
    );
  }
}