1 files changed, 129 insertions, 0 deletions
diff --git a/backend/internal/core/goal_service_test.go b/backend/internal/core/goal_service_test.go
new file mode 100644
index 0000000..2a4446a
--- /dev/null
+++ b/backend/internal/core/goal_service_test.go
@@ -0,0 +1,129 @@
+package core
+
+import (
+	"finance/backend/internal/models"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+	"gorm.io/gorm"
+)
+
+// Mock goal for testing
+func createTestGoal() *models.Goal {
+	return &models.Goal{
+		Model:         gorm.Model{ID: 1, CreatedAt: time.Now().Add(-30 * 24 * time.Hour)}, // created 30 days ago
+		UserID:        1,
+		Name:          "Test Goal",
+		TargetAmount:  10000,
+		CurrentAmount: 3000,
+		Status:        "Active",
+		TargetDate:    time.Now().Add(60 * 24 * time.Hour), // due in 60 days
+	}
+}
+
+// TestCalculateGoalProgress tests the goal progress calculation logic
+func TestCalculateGoalProgress(t *testing.T) {
+	// Create a test service
+	service := &GoalService{}
+
+	// Test with a goal that's on track
+	goal := createTestGoal()
+	progress, err := service.calculateGoalProgress(goal)
+
+	assert.NoError(t, err)
+	assert.NotNil(t, progress)
+
+	// Verify calculations
+	assert.Equal(t, int64(7000), progress.AmountRemaining)
+	assert.InDelta(t, 30.0, progress.PercentComplete, 0.1)
+
+	// Should have around 60 days remaining (might vary slightly based on test execution time)
+	assert.True(t, progress.DaysRemaining > 55 && progress.DaysRemaining <= 61)
+
+	// Test required amounts
+	assert.True(t, progress.RequiredPerDay > 0)
+	assert.True(t, progress.RequiredPerMonth > 0)
+
+	// Verify on track status - goal is at 30% completion, we're 1/3 through the time period
+	// so it should be on track
+	assert.True(t, progress.OnTrack)
+
+	// Test with a goal that's behind
+	goal.CurrentAmount = 1000 // only 10% complete after 1/3 of the time
+	progress, err = service.calculateGoalProgress(goal)
+
+	assert.NoError(t, err)
+	assert.NotNil(t, progress)
+	assert.False(t, progress.OnTrack)
+
+	// Test with a goal that has no target date
+	goal = createTestGoal()
+	goal.TargetDate = time.Time{} // zero time
+	progress, err = service.calculateGoalProgress(goal)
+
+	assert.NoError(t, err)
+	assert.NotNil(t, progress)
+	assert.True(t, progress.OnTrack) // should be on track if any progress made
+	assert.Equal(t, 0, progress.DaysRemaining)
+
+	// Test with a goal whose target date has passed
+	goal = createTestGoal()
+	goal.TargetDate = time.Now().Add(-10 * 24 * time.Hour) // 10 days ago
+	progress, err = service.calculateGoalProgress(goal)
+
+	assert.NoError(t, err)
+	assert.NotNil(t, progress)
+	assert.Equal(t, 0, progress.DaysRemaining)
+
+	// Not on track if target amount not reached
+	assert.False(t, progress.OnTrack)
+
+	// But should be on track if target amount reached despite date passed
+	goal.CurrentAmount = goal.TargetAmount
+	progress, err = service.calculateGoalProgress(goal)
+
+	assert.NoError(t, err)
+	assert.True(t, progress.OnTrack)
+}
+
+// TestUpdateGoalFromTransactions tests updating a goal based on transactions
+func TestUpdateGoalFromTransactions(t *testing.T) {
+	// This test would need a mock database to be fully implemented
+	// Here's a placeholder for when DB mocking is available
+
+	/*
+		// Setup a mock DB
+		db, mock := setupMockDB(t)
+		service := &GoalService{db: db}
+
+		// Setup expectations
+		goalID := uint(1)
+		userID := uint(1)
+
+		// Expect a query to fetch the goal
+		mock.ExpectQuery(`SELECT * FROM "goals" WHERE "id" = ?`).
+			WithArgs(goalID).
+			WillReturnRows(sqlmock.NewRows([]string{"id", "user_id", "name", "target_amount", "current_amount", "status"}).
+				AddRow(goalID, userID, "Test Goal", 10000, 0, "Active"))
+
+		// Expect a query to fetch transactions
+		mock.ExpectQuery(`SELECT * FROM "transactions" WHERE "user_id" = ? AND "category" = ?`).
+			WithArgs(userID, "Goal:1").
+			WillReturnRows(sqlmock.NewRows([]string{"id", "user_id", "amount", "type", "category"}).
+				AddRow(1, userID, 500, "Income", "Goal:1").
+				AddRow(2, userID, 300, "Income", "Goal:1").
+				AddRow(3, userID, 200, "Expense", "Goal:1"))
+
+		// Expect an update to the goal
+		mock.ExpectBegin()
+		mock.ExpectExec(`UPDATE "goals" SET`).
+			WithArgs(600, "Active", goalID). // 500 + 300 - 200 = 600
+			WillReturnResult(sqlmock.NewResult(1, 1))
+		mock.ExpectCommit()
+
+		// Run the test
+		err := service.UpdateGoalFromTransactions(goalID)
+		assert.NoError(t, err)
+	*/
+}