FIX: singularity faction donation formula (#619)

src/Faction/formulas/donation.ts

@@ -1,7 +1,31 @@
+import { Person as IPerson } from "@nsdefs";
+import { Player } from "@player";
+
 import { CONSTANTS } from "../../Constants";
 import { currentNodeMults } from "../../BitNode/BitNodeMultipliers";
-import { Person as IPerson } from "@nsdefs";
+import { Faction } from "../Faction";
 
 export function repFromDonation(amt: number, person: IPerson): number {
   return (amt / CONSTANTS.DonateMoneyToRepDivisor) * person.mults.faction_rep * currentNodeMults.FactionWorkRepGain;
 }
+
+export function repNeededToDonate(): number {
+  return Math.floor(CONSTANTS.BaseFavorToDonate * currentNodeMults.RepToDonateToFaction);
+}
+
+export function canDonate(amt: number): boolean {
+  return !isNaN(amt) && amt > 0 && Player.money >= amt;
+}
+
+/** Donates money to the faction provided and returns repuation gained */
+export function donate(amt: number, faction: Faction) {
+  if (!canDonate(amt)) {
+    return 0;
+  }
+
+  const repGain = repFromDonation(amt, Player);
+  Player.loseMoney(amt, "other");
+  faction.playerReputation += repGain;
+
+  return repGain;
+}