From ef272360fbf4728e7ddd5171272bb4b727089a3a Mon Sep 17 00:00:00 2001
From: Thomas <4159106+dtslvr@users.noreply.github.com>
Date: Sat, 5 Jun 2021 17:17:53 +0200
Subject: [PATCH] Feature/render average prices in position detail chart (#144)

* Render average buy prices

* Update changelog
---
 CHANGELOG.md                                  |  1 +
 .../src/app/portfolio/portfolio.service.ts    | 21 ++++++++++++++++++-
 apps/api/src/models/portfolio.ts              |  8 ++++++-
 3 files changed, 28 insertions(+), 2 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 72c39a37a..3e26d4c86 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,6 +10,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Added
 
 - Added a dedicated page for the account registration
+- Rendered the average buy prices in the position detail chart (useful for recurring transactions)
 
 ### Changed
 
diff --git a/apps/api/src/app/portfolio/portfolio.service.ts b/apps/api/src/app/portfolio/portfolio.service.ts
index e45fae214..44c055af0 100644
--- a/apps/api/src/app/portfolio/portfolio.service.ts
+++ b/apps/api/src/app/portfolio/portfolio.service.ts
@@ -20,6 +20,7 @@ import {
   getYear,
   isAfter,
   isSameDay,
+  parse,
   parseISO,
   setDate,
   setMonth,
@@ -215,6 +216,8 @@ export class PortfolioService {
         transactionCount
       } = portfolio.getPositions(new Date())[aSymbol];
 
+      const orders = portfolio.getOrders(aSymbol);
+
       const historicalData = await this.dataProviderService.getHistorical(
         [aSymbol],
         'day',
@@ -227,6 +230,7 @@ export class PortfolioService {
       }
 
       const historicalDataArray: HistoricalDataItem[] = [];
+      let currentAveragePrice: number;
       let maxPrice = marketPrice;
       let minPrice = marketPrice;
 
@@ -234,9 +238,24 @@ export class PortfolioService {
         for (const [date, { marketPrice }] of Object.entries(
           historicalData[aSymbol]
         )) {
+          const currentDate = parse(date, 'yyyy-MM-dd', new Date());
+          if (
+            isSameDay(currentDate, parseISO(orders[0]?.getDate())) ||
+            isAfter(currentDate, parseISO(orders[0]?.getDate()))
+          ) {
+            // Get snapshot of first day of month
+            const snapshot = portfolio.get(setDate(currentDate, 1))[0]
+              .positions[aSymbol];
+            orders.shift();
+
+            if (snapshot?.averagePrice) {
+              currentAveragePrice = snapshot?.averagePrice;
+            }
+          }
+
           historicalDataArray.push({
-            averagePrice,
             date,
+            averagePrice: currentAveragePrice,
             value: marketPrice
           });
 
diff --git a/apps/api/src/models/portfolio.ts b/apps/api/src/models/portfolio.ts
index 1176fa945..5cd26ba29 100644
--- a/apps/api/src/models/portfolio.ts
+++ b/apps/api/src/models/portfolio.ts
@@ -486,7 +486,13 @@ export class Portfolio implements PortfolioInterface {
       .reduce((previous, current) => previous + current, 0);
   }
 
-  public getOrders() {
+  public getOrders(aSymbol?: string) {
+    if (aSymbol) {
+      return this.orders.filter((order) => {
+        return order.getSymbol() === aSymbol;
+      });
+    }
+
     return this.orders;
   }