auto-generate invoice numberv0.2.0

2 files changed, 23 insertions, 0 deletions

diff --git a/invoice/controller.go b/invoice/controller.go
index 02bbaf5..7260834 100644
--- a/invoice/controller.go
+++ b/invoice/controller.go
@@ -101,6 +101,19 @@ func handleSaveInvoice (ctx *gin.Context) {
 	userId := uId.(uint)
 	invoice.UserID = userId
 
+	// if invoice number is 0, generate one!
+	if invoice.InvoiceNumber == 0 {
+		n, err := getNewInvoiceNumber(invoice.UserID)
+
+		if err != nil {
+			ctx.Error(err)
+			ctx.Abort()
+			return
+		}
+
+		invoice.InvoiceNumber = n
+	}
+
 	err := invoice.upsert()
 	if err != nil {
 		ctx.Error(err)
diff --git a/invoice/service.go b/invoice/service.go
index 099f6a0..3dcc5e2 100644
--- a/invoice/service.go
+++ b/invoice/service.go
@@ -21,6 +21,16 @@ import (
 	e "vidhukant.com/openbills/errors"
 )
 
+// returns greatest invoice number + 1
+func getNewInvoiceNumber(userId uint) (uint, error) {
+	var i uint
+
+	row := db.Model(&Invoice{}).Where("user_id = ?", userId).Select("max(invoice_number)").Row()
+	err := row.Scan(&i)
+
+	return i + 1, err
+}
+
 func getInvoice(invoice *Invoice, id uint) error {
 	res := db.Preload("BillingAddress").Preload("ShippingAddress").Preload("Items").Find(&invoice, id)