From 02a4fad443f27ded71e332b351c24f9dae88be32 Mon Sep 17 00:00:00 2001
From: jordi fita mas <jordi@tandem.blog>
Date: Sun, 21 May 2023 18:59:42 +0200
Subject: [PATCH] Refactor a bit the code that draws SVG polylines in circles

---
 pkg/dashboard.go | 31 +++++++++++++++----------------
 1 file changed, 15 insertions(+), 16 deletions(-)

diff --git a/pkg/dashboard.go b/pkg/dashboard.go
index 19d1f6e..b1ff83c 100644
--- a/pkg/dashboard.go
+++ b/pkg/dashboard.go
@@ -240,25 +240,24 @@ func buildDashboardChart(ctx context.Context, conn *Conn, company *Company, peri
 	var sb strings.Builder
 	sb.WriteString(fmt.Sprintf("<svg id='income-chart' viewBox='-10 -10 %d %d'>", int(width)+20, int(height)+20))
 	sb.WriteString("<rect x='-10' y='-10' width='100%', height='100%'/>")
-	sb.WriteString("<polyline points='")
-	for i, v := range values {
-		sb.WriteString(fmt.Sprintf(" %f,%f", float64(i)/dataPoints*width, height-v.sales/max*height))
+	writePolyline := func(value func(value) float64) {
+		sb.WriteString("<polyline points='")
+		for i, v := range values {
+			sb.WriteString(fmt.Sprintf(" %f,%f", float64(i)/dataPoints*width, height-value(v)/max*height))
+		}
+		sb.WriteString("'/>")
 	}
-	sb.WriteString("'/>")
-	sb.WriteString("<polyline points='")
-	for i, v := range values {
-		sb.WriteString(fmt.Sprintf(" %f,%f", float64(i)/dataPoints*width, height-v.income/max*height))
+	writePolyline(func(v value) float64 { return v.sales })
+	writePolyline(func(v value) float64 { return v.income })
+	writePolyline(func(v value) float64 { return v.expenses })
+
+	writeCircle := func(i int, v float64) {
+		sb.WriteString(fmt.Sprintf("<circle cx='%f' cy='%f' r='4'></circle>", float64(i)/dataPoints*width, height-v/max*height))
 	}
-	sb.WriteString("'/>")
-	sb.WriteString("<polyline points='")
 	for i, v := range values {
-		sb.WriteString(fmt.Sprintf(" %f,%f", float64(i)/dataPoints*width, height-v.expenses/max*height))
-	}
-	sb.WriteString("'/>")
-	for i, v := range values {
-		sb.WriteString(fmt.Sprintf("<circle cx='%f' cy='%f' r='4'/>", float64(i)/dataPoints*width, height-v.sales/max*height))
-		sb.WriteString(fmt.Sprintf("<circle cx='%f' cy='%f' r='4'/>", float64(i)/dataPoints*width, height-v.income/max*height))
-		sb.WriteString(fmt.Sprintf("<circle cx='%f' cy='%f' r='4'/>", float64(i)/dataPoints*width, height-v.expenses/max*height))
+		writeCircle(i, v.sales)
+		writeCircle(i, v.income)
+		writeCircle(i, v.expenses)
 	}
 	sb.WriteString("</svg>")
 	return template.HTML(sb.String())