From b56738653d522af005c5fa65f12bf82476697daf Mon Sep 17 00:00:00 2001
From: Sebastiaan de Schaetzen <sebastiaan.de.schaetzen@gmail.com>
Date: Sun, 18 May 2025 08:51:37 +0200
Subject: [PATCH] Add complete task test with sum of weights == 0

---
 backend/api_test.go | 42 ++++++++++++++++++++++++++++++++++++++++++
 backend/db.go       | 34 ++++++++++++++++++----------------
 2 files changed, 60 insertions(+), 16 deletions(-)

diff --git a/backend/api_test.go b/backend/api_test.go
index 9273fa6..a5eaf29 100644
--- a/backend/api_test.go
+++ b/backend/api_test.go
@@ -594,6 +594,38 @@ func TestCompleteTask(t *testing.T) {
 	}
 }
 
+func TestCompleteTaskAllowanceWeightsSumTo0(t *testing.T) {
+	e := startServer(t)
+	taskId := createTestTaskWithAmount(e, 101)
+
+	e.GET("/tasks").Expect().Status(200).JSON().Array().Length().IsEqual(1)
+
+	// Update rest allowance
+	e.PUT("/user/1/allowance/0").WithJSON(UpdateAllowanceRequest{
+		Weight: 0,
+	}).Expect().Status(200)
+	// Create two allowance goals
+	e.POST("/user/1/allowance").WithJSON(CreateAllowanceRequest{
+		Name:   "Test Allowance 1",
+		Target: 1000,
+		Weight: 0,
+	}).Expect().Status(201)
+
+	// Complete the task
+	e.POST("/task/" + strconv.Itoa(taskId) + "/complete").Expect().Status(200)
+
+	// Verify the task is marked as completed
+	e.GET("/task/" + strconv.Itoa(taskId)).Expect().Status(404)
+
+	// Verify the allowances are updated for user 1
+	allowances := e.GET("/user/1/allowance").Expect().Status(200).JSON().Array()
+	allowances.Length().IsEqual(2)
+	allowances.Value(0).Object().Value("id").Number().IsEqual(0)
+	allowances.Value(0).Object().Value("progress").Number().IsEqual(101)
+	allowances.Value(1).Object().Value("id").Number().IsEqual(1)
+	allowances.Value(1).Object().Value("progress").Number().IsEqual(0)
+}
+
 func TestCompleteTaskInvalidId(t *testing.T) {
 	e := startServer(t)
 	e.POST("/task/999/complete").Expect().Status(404)
@@ -628,6 +660,16 @@ func TestCompleteAllowance(t *testing.T) {
 	history.Value(1).Object().Value("timestamp").String().AsDateTime().InRange(getDelta(time.Now(), 2.0))
 }
 
+func TestCompleteAllowanceInvalidUserId(t *testing.T) {
+	e := startServer(t)
+	e.POST("/user/999/allowance/1/complete").Expect().Status(404)
+}
+
+func TestCompleteAllowanceInvalidAllowanceId(t *testing.T) {
+	e := startServer(t)
+	e.POST("/user/1/allowance/999/complete").Expect().Status(404)
+}
+
 func getDelta(base time.Time, delta float64) (time.Time, time.Time) {
 	start := base.Add(-time.Duration(delta) * time.Second)
 	end := base.Add(time.Duration(delta) * time.Second)
diff --git a/backend/db.go b/backend/db.go
index 937be11..100040c 100644
--- a/backend/db.go
+++ b/backend/db.go
@@ -389,24 +389,26 @@ func (db *Db) CompleteTask(taskId int) error {
 
 		remainingReward := reward
 
-		// Distribute the reward to the allowances
-		for allowanceRow := range tx.Query("select id, weight from allowances where user_id = ? and weight > 0").Bind(userId).Range(&err) {
-			var allowanceId int
-			var allowanceWeight float64
-			err = allowanceRow.Scan(&allowanceId, &allowanceWeight)
-			if err != nil {
-				return err
-			}
+		if sumOfWeights > 0 {
+			// Distribute the reward to the allowances
+			for allowanceRow := range tx.Query("select id, weight from allowances where user_id = ? and weight > 0").Bind(userId).Range(&err) {
+				var allowanceId int
+				var allowanceWeight float64
+				err = allowanceRow.Scan(&allowanceId, &allowanceWeight)
+				if err != nil {
+					return err
+				}
 
-			// Calculate the amount to add to the allowance
-			amount := int((allowanceWeight / sumOfWeights) * float64(remainingReward))
-			sumOfWeights -= allowanceWeight
-			err = tx.Query("update allowances set balance = balance + ? where id = ? and user_id = ?").
-				Bind(amount, allowanceId, userId).Exec()
-			if err != nil {
-				return err
+				// Calculate the amount to add to the allowance
+				amount := int((allowanceWeight / sumOfWeights) * float64(remainingReward))
+				sumOfWeights -= allowanceWeight
+				err = tx.Query("update allowances set balance = balance + ? where id = ? and user_id = ?").
+					Bind(amount, allowanceId, userId).Exec()
+				if err != nil {
+					return err
+				}
+				remainingReward -= amount
 			}
-			remainingReward -= amount
 		}
 
 		// Add the remaining reward to the user