From 7b3cf4845344492756a7822b402de63dc5c07e02 Mon Sep 17 00:00:00 2001
From: catloversg <152669316+catloversg@users.noreply.github.com>
Date: Fri, 7 Jun 2024 13:10:16 +0700
Subject: [PATCH] CORPORATION: Refactor markup multiplier (#1362)

---
 src/Corporation/Division.ts                   | 32 ++++---------------
 src/Corporation/helpers.ts                    | 23 +++++++++++++
 .../optimal-selling-price-market-ta2.md       | 11 ++++---
 3 files changed, 36 insertions(+), 30 deletions(-)

diff --git a/src/Corporation/Division.ts b/src/Corporation/Division.ts
index ebf00a409..124c58e79 100644
--- a/src/Corporation/Division.ts
+++ b/src/Corporation/Division.ts
@@ -15,6 +15,7 @@ import { JSONMap, JSONSet } from "../Types/Jsonable";
 import { PartialRecord, getRecordEntries, getRecordKeys, getRecordValues } from "../Types/Record";
 import { Material } from "./Material";
 import { getKeyList } from "../utils/helpers/getKeyList";
+import { calculateMarkupMultiplier } from "./helpers";
 
 interface DivisionParams {
   name: string;
@@ -582,26 +583,13 @@ export class Division {
             }
             mat.uiMarketPrice = sCost;
 
-            // Calculate how much of the material sells (per second)
-            let markup = 1;
-            if (sCost > mat.marketPrice) {
-              //Penalty if difference between sCost and bCost is greater than markup limit
-              if (sCost - mat.marketPrice > markupLimit) {
-                markup = Math.pow(markupLimit / (sCost - mat.marketPrice), 2);
-              }
-            } else if (sCost < mat.marketPrice) {
-              if (sCost <= 0) {
-                markup = 1e12; //Sell everything, essentially discard
-              } else {
-                //Lower prices than market increases sales
-                markup = mat.marketPrice / sCost;
-              }
-            }
+            const markupMultiplier = calculateMarkupMultiplier(sCost, mat.marketPrice, markupLimit);
 
+            // Calculate how much of the material sells (per second)
             mat.maxSellPerCycle =
               (mat.quality + 0.001) *
               marketFactor *
-              markup *
+              markupMultiplier *
               businessFactor *
               corporation.getSalesMult() *
               advertisingFactor *
@@ -920,21 +908,15 @@ export class Division {
             sCost = sellPrice;
           }
           product.uiMarketPrice[city] = sCost;
-          let markup = 1;
-          if (sCost > product.cityData[city].productionCost) {
-            if (sCost - product.cityData[city].productionCost > markupLimit) {
-              markup = markupLimit / (sCost - product.cityData[city].productionCost);
-            }
-          } else if (sCost <= 0) {
-            markup = 1e12; //Sell everything, essentially discard - as materials
-          }
+
+          const markupMultiplier = calculateMarkupMultiplier(sCost, product.cityData[city].productionCost, markupLimit);
 
           product.maxSellAmount =
             0.5 *
             Math.pow(product.cityData[city].effectiveRating, 0.65) *
             marketFactor *
             corporation.getSalesMult() *
-            Math.pow(markup, 2) *
+            markupMultiplier *
             businessFactor *
             advertisingFactor *
             this.getSalesMultiplier();
diff --git a/src/Corporation/helpers.ts b/src/Corporation/helpers.ts
index b515cd67f..c9a431e11 100644
--- a/src/Corporation/helpers.ts
+++ b/src/Corporation/helpers.ts
@@ -88,3 +88,26 @@ export function issueNewSharesFailureReason(corp: Corporation, numShares: number
 
   return "";
 }
+
+export function calculateMarkupMultiplier(sellingPrice: number, marketPrice: number, markupLimit: number): number {
+  // Sanitize sellingPrice
+  if (!Number.isFinite(sellingPrice)) {
+    return 1;
+  }
+  let markupMultiplier = 1;
+  if (sellingPrice > marketPrice) {
+    // markupMultiplier is a penalty modifier if sellingPrice is greater than the sum of marketPrice and markupLimit.
+    if (sellingPrice > marketPrice + markupLimit) {
+      markupMultiplier = Math.pow(markupLimit / (sellingPrice - marketPrice), 2);
+    }
+  } else {
+    if (sellingPrice <= 0) {
+      // Discard
+      markupMultiplier = 1e12;
+    } else {
+      // markupMultiplier is a bonus modifier if sellingPrice is less than marketPrice.
+      markupMultiplier = marketPrice / sellingPrice;
+    }
+  }
+  return markupMultiplier;
+}
diff --git a/src/Documentation/doc/advanced/corporation/optimal-selling-price-market-ta2.md b/src/Documentation/doc/advanced/corporation/optimal-selling-price-market-ta2.md
index 25dde7b01..35a4b1db5 100644
--- a/src/Documentation/doc/advanced/corporation/optimal-selling-price-market-ta2.md
+++ b/src/Documentation/doc/advanced/corporation/optimal-selling-price-market-ta2.md
@@ -63,12 +63,13 @@ $$MarketFactor = Max\left(0.1,{Demand\ast(100 - Competition)}\ast{0.01}\right)$$
 - Division's research bonus: this is always 1. Currently there is not any research that increases the sales bonus.
 - `MarkupMultiplier`: initialize with 1.
   - `SellingPrice` is the selling price that you set.
-  - With materials, if we set `SellingPrice` to 0, `MarkupMultiplier` is $10^{12}$ (check the formula below). Extremely high `MarkupMultiplier` means that we can sell all units, regardless of other factors. This is the fastest way to discard materials.
-  - If `(SellingPrice > MarketPrice + MarkupLimit)`:
-    $$MarkupMultiplier = \left(\frac{MarkupLimit}{SellingPrice - MarketPrice}\right)^{2}$$
-  - If item is material and `SellingPrice` is less than `MarketPrice`:
+  - If we set `SellingPrice` to 0 or a negative number, `MarkupMultiplier` is $10^{12}$ (check the formula below). With an extremely high `MarkupMultiplier`, we can sell all units, regardless of other factors. This is the fastest way to discard stored units.
+  - If `(SellingPrice > MarketPrice)`:
+    - If `(SellingPrice > MarketPrice + MarkupLimit)`:
+      $$MarkupMultiplier = \left(\frac{MarkupLimit}{SellingPrice - MarketPrice}\right)^{2}$$
+  - If `(SellingPrice <= MarketPrice)`:
 
-$$MarkupMultiplier = \begin{cases}\frac{MarketPrice}{SellingPrice}, & SellingPrice > 0 \land SellingPrice < MarketPrice \newline 10^{12}, & SellingPrice \leq 0 \end{cases}$$
+$$MarkupMultiplier = \begin{cases}\frac{MarketPrice}{SellingPrice}, & SellingPrice > 0 \newline 10^{12}, & SellingPrice \leq 0 \end{cases}$$
 
 ## Optimal selling price