From a61e057cfb5cd3613d070208fc508e3436591a68 Mon Sep 17 00:00:00 2001
From: Luca <Luca@hackerspace-bamberg.de>
Date: Mon, 6 Mar 2023 00:42:51 +0100
Subject: [PATCH] Calculate per-category sub-totals

---
 internal/pretix/order_placed.go | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/internal/pretix/order_placed.go b/internal/pretix/order_placed.go
index 77787f2..7ef6105 100644
--- a/internal/pretix/order_placed.go
+++ b/internal/pretix/order_placed.go
@@ -23,6 +23,8 @@ const (
 var adverbs = []string{" Außerdem ", " Zusätzlich ", " Weiterhin ", " Des Weiteren "}
 
 type categoryBin struct {
+	Cents	uint
+	Euros	uint
 	NumFree	uint
 	NumPaid	uint
 }
@@ -77,7 +79,6 @@ func (s Server) orderPlaced(w http.ResponseWriter, r *http.Request) {
 			Item	uint
 			Price	string
 		}
-		Total		string
 	}{}
 
 	err = decoder.Decode(&order)
@@ -111,6 +112,12 @@ func (s Server) orderPlaced(w http.ResponseWriter, r *http.Request) {
 
 			category := categories[name]
 			if euros > 0 || cents > 0 {
+				category.Cents += cents
+				if carry := category.Cents / 100; carry > 0 {
+					category.Cents -= carry * 100
+					category.Euros += carry
+				}
+				category.Euros += euros
 				category.NumPaid++
 			} else {
 				category.NumFree++
@@ -154,15 +161,15 @@ func (s Server) orderPlaced(w http.ResponseWriter, r *http.Request) {
 				preposition = `aus der Kategorie "`
 				quote = `" `
 			}
-			if totalEuros, totalCents, err := parsePrice(order.Total); err == nil && (totalEuros > 0 || totalCents > 0) {
+			if bin.Euros > 0 || bin.Cents > 0 {
 				var adverb, fraction string
 				if bin.NumPaid > 1 {
 					adverb = "insgesamt "
 				}
-				if totalCents > 0 {
-					fraction = fmt.Sprintf(",%02d", totalCents)
+				if bin.Cents > 0 {
+					fraction = fmt.Sprintf(",%02d", bin.Cents)
 				}
-				total = fmt.Sprint("für ", adverb, totalEuros, fraction, " Euro ")
+				total = fmt.Sprint("für ", adverb, bin.Euros, fraction, " Euro ")
 			}
 
 			body.WriteString(fmt.Sprint(adverb, verb, free, conjunction, paid, noun, preposition, category, quote, total, "bestellt."))