Function toCostBaseQuantity

toCostBaseQuantity(quantity: number, uom: string): undefined | QuantityObject

Normalizes a quantity to the base unit used for per-unit cost comparison: grams for mass, millilitres for volume, and the unchanged countable unit for pieces/each. Unlike toBaseQuantity (which returns milligrams for mass), this steps mass up to grams so a cost-per-gram reads naturally. Returns undefined for an unrecognized unit or a non-positive quantity, so callers can safely divide by the result.

Parameters

quantity: number
The quantity to convert.
uom: string
The unit of measure of the quantity (canonical or alias form).

Returns undefined | QuantityObject

The quantity in its cost base unit (g / ml / countable), or undefined.

Example

toCostBaseQuantity(1, "kg")  // Returns { quantity: 1000, uom: "g" }
toCostBaseQuantity(2, "l")   // Returns { quantity: 2000, uom: "ml" }
toCostBaseQuantity(5, "pcs") // Returns { quantity: 5, uom: "pcs" }
toCostBaseQuantity(0, "g")   // Returns undefined

Source

export function toCostBaseQuantity(quantity: number, uom: string): QuantityObject | undefined {
  if (typeof quantity !== 'number' || quantity <= 0) return undefined;

  const standardized = standardizeUom(uom);
  if (!standardized) return undefined;

  switch (getUomKind(standardized)) {
    case 'mass':
      // toBaseQuantity returns milligrams for mass; step up to grams.
      return { quantity: toBaseQuantity(quantity, standardized) / 1000, uom: UOM.G };
    case 'volume':
      return { quantity: toBaseQuantity(quantity, standardized), uom: UOM.ML };
    case 'count':
      return { quantity, uom: standardized };
    default:
      return undefined;
  }
}