edr-platform/apps/edr-freight-api/src/migrations/3470000000000-ShippingLineRates.ts

import { MigrationInterface, QueryRunner } from 'typeorm';

/**
 * Per-shipping-line rates.
 *
 * A shipping line books rail capacity directly (see BookingShippingLine3450000000000)
 * and negotiates its own prices, so the rate table gains an owner column:
 * `shipping_line_company_id` NULL = the standard rate every customer pays,
 * NOT NULL = a rate that only that line's bookings resolve.
 *
 * Points at `freight.shipping_line_companies` (the portal account that owns the
 * booking), NOT `freight.shipping_lines` — the latter is carrier reference data
 * naming who physically moves the goods, and the existing SHIPPING_LINE trigger
 * already keys off it. Both stay independent.
 *
 * Line rates OVERRIDE rather than stack: a booking owned by a line prices off
 * that line's rate for the lane, and is hard-blocked when none exists (the
 * standard rate is deliberately not a fallback — see RuleEngineService).
 *
 * Every existing row keeps a NULL owner, so nothing needs backfilling and the
 * standard-rate lookups behave exactly as before.
 */
export class ShippingLineRates3470000000000 implements MigrationInterface {
  public async up(queryRunner: QueryRunner): Promise<void> {
    await queryRunner.query(`
      ALTER TABLE freight.rates
        ADD COLUMN IF NOT EXISTS shipping_line_company_id uuid
    `);

    await queryRunner.query(`
      ALTER TABLE freight.rates
        DROP CONSTRAINT IF EXISTS "FK_rates_shipping_line_company"
    `);
    await queryRunner.query(`
      ALTER TABLE freight.rates
        ADD CONSTRAINT "FK_rates_shipping_line_company"
        FOREIGN KEY (shipping_line_company_id)
        REFERENCES freight.shipping_line_companies (id)
        ON DELETE RESTRICT
    `);

    // Rate resolution always filters by owner, so the lookups this column
    // participates in are (owner, lane) — indexed together with rate_type,
    // which every lookup also pins.
    await queryRunner.query(`
      CREATE INDEX IF NOT EXISTS idx_rates_shipping_line_company_id
        ON freight.rates (shipping_line_company_id)
    `);
    await queryRunner.query(`
      CREATE INDEX IF NOT EXISTS idx_rates_shipping_line_lane
        ON freight.rates (shipping_line_company_id, rate_type, origin_yard_id, destination_yard_id)
        WHERE shipping_line_company_id IS NOT NULL
    `);

    // A shipping line sells import freight only — the export leg is contracted
    // through the customer, not the carrier. Enforced here so a line rate can
    // never be filed against an export lane regardless of which API path wrote
    // it. Surcharges carry no direction and are unaffected.
    await queryRunner.query(`
      ALTER TABLE freight.rates
        DROP CONSTRAINT IF EXISTS "CK_rates_shipping_line_import_only"
    `);
    await queryRunner.query(`
      ALTER TABLE freight.rates
        ADD CONSTRAINT "CK_rates_shipping_line_import_only" CHECK (
          deleted_at IS NOT NULL OR status = 'SUPERSEDED' OR
          shipping_line_company_id IS NULL OR
          trade_direction IS NULL OR trade_direction = 'IMPORT'
        )
    `);

    // The owner joins the rate's identity. Without it MSC's 20ft Djibouti→Modjo
    // rate collides with the standard rate for the same lane — same rate_type,
    // same scope, same unit — and the insert fails on UQ_rates_pattern. NULL
    // (the standard rate) collapses to the zero uuid like every other nullable
    // scope column, so existing rows keep their current uniqueness exactly.
    await queryRunner.query(`DROP INDEX IF EXISTS freight."UQ_rates_pattern"`);
    await queryRunner.query(`
      CREATE UNIQUE INDEX IF NOT EXISTS "UQ_rates_pattern" ON freight.rates USING btree (
        rate_type,
        COALESCE(shipping_line_company_id, '00000000-0000-0000-0000-000000000000'::uuid),
        COALESCE(container_type_id, '00000000-0000-0000-0000-000000000000'::uuid),
        COALESCE(cargo_type_id, '00000000-0000-0000-0000-000000000000'::uuid),
        COALESCE(trade_direction, ''::character varying),
        COALESCE(origin_yard_id, '00000000-0000-0000-0000-000000000000'::uuid),
        COALESCE(destination_yard_id, '00000000-0000-0000-0000-000000000000'::uuid),
        rate_unit,
        COALESCE(min_km, '-1'::numeric)
      ) WHERE ((deleted_at IS NULL) AND ((status)::text <> 'SUPERSEDED'::text))
    `);
  }

  public async down(queryRunner: QueryRunner): Promise<void> {
    // Restore the pre-owner pattern index (as left by LastMileRateBands).
    await queryRunner.query(`DROP INDEX IF EXISTS freight."UQ_rates_pattern"`);
    await queryRunner.query(`
      CREATE UNIQUE INDEX IF NOT EXISTS "UQ_rates_pattern" ON freight.rates USING btree (
        rate_type,
        COALESCE(container_type_id, '00000000-0000-0000-0000-000000000000'::uuid),
        COALESCE(cargo_type_id, '00000000-0000-0000-0000-000000000000'::uuid),
        COALESCE(trade_direction, ''::character varying),
        COALESCE(origin_yard_id, '00000000-0000-0000-0000-000000000000'::uuid),
        COALESCE(destination_yard_id, '00000000-0000-0000-0000-000000000000'::uuid),
        rate_unit,
        COALESCE(min_km, '-1'::numeric)
      ) WHERE ((deleted_at IS NULL) AND ((status)::text <> 'SUPERSEDED'::text))
    `);

    await queryRunner.query(`
      ALTER TABLE freight.rates
        DROP CONSTRAINT IF EXISTS "CK_rates_shipping_line_import_only"
    `);
    await queryRunner.query(
      `DROP INDEX IF EXISTS freight.idx_rates_shipping_line_lane`,
    );
    await queryRunner.query(
      `DROP INDEX IF EXISTS freight.idx_rates_shipping_line_company_id`,
    );
    await queryRunner.query(`
      ALTER TABLE freight.rates
        DROP CONSTRAINT IF EXISTS "FK_rates_shipping_line_company"
    `);
    await queryRunner.query(`
      ALTER TABLE freight.rates DROP COLUMN IF EXISTS shipping_line_company_id
    `);
  }
}