From 1cf3aae6597d7dcac7cc13c61fc22110d7f0c3a3 Mon Sep 17 00:00:00 2001
From: Thomas Kaul <4159106+dtslvr@users.noreply.github.com>
Date: Sun, 3 Mar 2024 21:40:11 +0100
Subject: [PATCH] Fix average price

---
 apps/api/jest.config.ts                       |  1 -
 .../transaction-point-symbol.interface.ts     |  1 +
 .../src/app/portfolio/portfolio-calculator.ts | 38 ++++++++++---------
 .../src/app/portfolio/portfolio.service.ts    |  5 +--
 4 files changed, 23 insertions(+), 22 deletions(-)

diff --git a/apps/api/jest.config.ts b/apps/api/jest.config.ts
index 8152c3f2a..b87f91a79 100644
--- a/apps/api/jest.config.ts
+++ b/apps/api/jest.config.ts
@@ -13,7 +13,6 @@ export default {
   },
   moduleFileExtensions: ['ts', 'js', 'html'],
   coverageDirectory: '../../coverage/apps/api',
-  testTimeout: 10000,
   testEnvironment: 'node',
   preset: '../../jest.preset.js'
 };
diff --git a/apps/api/src/app/portfolio/interfaces/transaction-point-symbol.interface.ts b/apps/api/src/app/portfolio/interfaces/transaction-point-symbol.interface.ts
index 5f8e64406..fb2f0a389 100644
--- a/apps/api/src/app/portfolio/interfaces/transaction-point-symbol.interface.ts
+++ b/apps/api/src/app/portfolio/interfaces/transaction-point-symbol.interface.ts
@@ -2,6 +2,7 @@ import { DataSource, Tag } from '@prisma/client';
 import Big from 'big.js';
 
 export interface TransactionPointSymbol {
+  averagePrice: Big;
   currency: string;
   dataSource: DataSource;
   dividend: Big;
diff --git a/apps/api/src/app/portfolio/portfolio-calculator.ts b/apps/api/src/app/portfolio/portfolio-calculator.ts
index 2bad796d9..966ebebdf 100644
--- a/apps/api/src/app/portfolio/portfolio-calculator.ts
+++ b/apps/api/src/app/portfolio/portfolio-calculator.ts
@@ -78,32 +78,29 @@ export class PortfolioCalculator {
       const oldAccumulatedSymbol = symbols[order.symbol];
 
       const factor = getFactor(order.type);
-      const unitPrice = new Big(order.unitPrice);
 
       if (oldAccumulatedSymbol) {
+        let investment = oldAccumulatedSymbol.investment;
+
         const newQuantity = order.quantity
           .mul(factor)
           .plus(oldAccumulatedSymbol.quantity);
 
-        let investment = oldAccumulatedSymbol.investment;
-
-        if (newQuantity.gt(0)) {
-          if (order.type === 'BUY') {
-            investment = oldAccumulatedSymbol.investment.plus(
-              order.quantity.mul(unitPrice)
-            );
-          } else if (order.type === 'SELL') {
-            const averagePrice = oldAccumulatedSymbol.investment.div(
-              oldAccumulatedSymbol.quantity
-            );
-            investment = oldAccumulatedSymbol.investment.minus(
-              order.quantity.mul(averagePrice)
-            );
-          }
+        if (order.type === 'BUY') {
+          investment = oldAccumulatedSymbol.investment.plus(
+            order.quantity.mul(order.unitPrice)
+          );
+        } else if (order.type === 'SELL') {
+          investment = oldAccumulatedSymbol.investment.minus(
+            order.quantity.mul(oldAccumulatedSymbol.averagePrice)
+          );
         }
 
         currentTransactionPointItem = {
           investment,
+          averagePrice: newQuantity.gt(0)
+            ? investment.div(newQuantity)
+            : new Big(0),
           currency: order.currency,
           dataSource: order.dataSource,
           dividend: new Big(0),
@@ -116,12 +113,13 @@ export class PortfolioCalculator {
         };
       } else {
         currentTransactionPointItem = {
+          averagePrice: order.unitPrice,
           currency: order.currency,
           dataSource: order.dataSource,
           dividend: new Big(0),
           fee: order.fee,
           firstBuyDate: order.date,
-          investment: unitPrice.mul(order.quantity).mul(factor),
+          investment: order.unitPrice.mul(order.quantity).mul(factor),
           quantity: order.quantity.mul(factor),
           symbol: order.symbol,
           tags: order.tags,
@@ -132,22 +130,28 @@ export class PortfolioCalculator {
       symbols[order.symbol] = currentTransactionPointItem;
 
       const items = lastTransactionPoint?.items ?? [];
+
       const newItems = items.filter(
         (transactionPointItem) => transactionPointItem.symbol !== order.symbol
       );
+
       newItems.push(currentTransactionPointItem);
+
       newItems.sort((a, b) => {
         return a.symbol?.localeCompare(b.symbol);
       });
+
       if (lastDate !== currentDate || lastTransactionPoint === null) {
         lastTransactionPoint = {
           date: currentDate,
           items: newItems
         };
+
         this.transactionPoints.push(lastTransactionPoint);
       } else {
         lastTransactionPoint.items = newItems;
       }
+
       lastDate = currentDate;
     }
   }
diff --git a/apps/api/src/app/portfolio/portfolio.service.ts b/apps/api/src/app/portfolio/portfolio.service.ts
index 6f63916e1..d55b3d647 100644
--- a/apps/api/src/app/portfolio/portfolio.service.ts
+++ b/apps/api/src/app/portfolio/portfolio.service.ts
@@ -753,7 +753,6 @@ export class PortfolioService {
         averagePrice,
         currency,
         dataSource,
-        dividend,
         dividendInBaseCurrency,
         fee,
         firstBuyDate,
@@ -804,9 +803,7 @@ export class PortfolioService {
           );
 
           if (currentSymbol) {
-            currentAveragePrice = currentSymbol.quantity.eq(0)
-              ? 0
-              : currentSymbol.investment.div(currentSymbol.quantity).toNumber();
+            currentAveragePrice = currentSymbol.averagePrice.toNumber();
             currentQuantity = currentSymbol.quantity.toNumber();
           }