refactor: parallelize queries for better performance (#7)

src/lib/monthly-overview.js

@@ -1,30 +1,53 @@
-export const getMonthlyOverview = async (supabase, year, month) => {
-	const currentMonth = new Date(year, month, 1).toDateString();
-	const nextMonth = new Date(year, month + 1, 1).toDateString();
+const getExpenses = async (supabase, currentMonth, nextMonth) => {
 	const { data: expenses } = await supabase
 		.from('expenses')
 		.select('id,date,category,description,amount')
 		.gte('date', currentMonth)
 		.lt('date', nextMonth);
 
+	return expenses;
+};
+
+const getIncome = async (supabase, currentMonth, nextMonth) => {
 	const { data: income } = await supabase
 		.from('income')
 		.select('id,date,category,description,amount')
 		.gte('date', currentMonth)
 		.lt('date', nextMonth);
 
+	return income;
+};
+
+const getSavings = async (supabase, currentMonth, nextMonth) => {
 	const { data: savings } = await supabase
 		.from('savings')
 		.select('id,date,category,description,amount')
 		.gte('date', currentMonth)
 		.lt('date', nextMonth);
 
+	return savings;
+};
+
+const getDebt = async (supabase, currentMonth, nextMonth) => {
 	const { data: debt } = await supabase
 		.from('debt')
 		.select('id,date,category,description,amount,interest_rate,minimum_payment')
 		.gte('date', currentMonth)
 		.lt('date', nextMonth);
 
+	return debt;
+};
+
+export const getMonthlyOverview = async (supabase, year, month) => {
+	const currentMonth = new Date(year, month, 1).toDateString();
+	const nextMonth = new Date(year, month + 1, 1).toDateString();
+	const [expenses, income, savings, debt] = await Promise.all([
+		getExpenses(supabase, currentMonth, nextMonth),
+		getIncome(supabase, currentMonth, nextMonth),
+		getSavings(supabase, currentMonth, nextMonth),
+		getDebt(supabase, currentMonth, nextMonth),
+	]);
+
 	return {
 		expenses,
 		income,