-- Adds the two receipt workflow states used by the goods-receipt tracking UI.
ALTER TABLE PurchaseOrders
  MODIFY COLUMN status ENUM(
    'draft',
    'sent',
    'confirmed',
    'in_progress',
    'in_receipt',
    'received',
    'completed',
    'cancelled'
  ) NOT NULL DEFAULT 'draft',
  ADD COLUMN receiptInProgress TINYINT(1) NOT NULL DEFAULT 0,
  ADD COLUMN lastReceiptDate DATE NULL,
  ADD COLUMN receivedDate DATE NULL,
  ADD COLUMN receivedBy VARCHAR(255) NULL,
  ADD COLUMN receiptNotes TEXT NULL;