diff options
Diffstat (limited to 'packages/taler-util/src/amounts.ts')
-rw-r--r-- | packages/taler-util/src/amounts.ts | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/packages/taler-util/src/amounts.ts b/packages/taler-util/src/amounts.ts index d4e798030..a998c8f63 100644 --- a/packages/taler-util/src/amounts.ts +++ b/packages/taler-util/src/amounts.ts @@ -95,6 +95,11 @@ export interface Result { */ export type AmountLike = AmountString | AmountJson; +export interface DivmodResult { + quotient: number; + remainder: AmountJson; +} + /** * Helper class for dealing with amounts. */ @@ -135,6 +140,29 @@ export class Amounts { return amt; } + static divmod(a1: AmountLike, a2: AmountLike): DivmodResult { + const am1 = Amounts.jsonifyAmount(a1); + const am2 = Amounts.jsonifyAmount(a2); + if (am1.currency != am2.currency) { + throw Error(`incompatible currency (${am1.currency} vs${am2.currency})`); + } + + const x1 = BigInt(am1.value) * BigInt(amountFractionalBase) + BigInt(am1.fraction); + const x2 = BigInt(am2.value) * BigInt(amountFractionalBase) + BigInt(am2.fraction); + + const quotient = x1 / x2; + const remainderScaled = x1 % x2; + + return { + quotient: Number(quotient), + remainder: { + currency: am1.currency, + value: Number(remainderScaled / BigInt(amountFractionalBase)), + fraction: Number(remainderScaled % BigInt(amountFractionalBase)) + } + } + } + static sum(amounts: AmountLike[]): Result { if (amounts.length <= 0) { throw Error("can't sum zero amounts"); |