string typescript is on

src/components/Calculator.js → src/components/Calculator.tsx

@@ -5,14 +5,17 @@ import { getSalaryInfo, formatCurrency } from "./utils";
 import "./Calculator.css";
 
 const Calculator = () => {
-  const [salary, setSalary] = useState(70000);
+  const [salary, setSalary] = useState<string>("70000");
 
-  const handleChangeSalary = (event) => {
-    setSalary(event.target.value);
+  const handleChangeSalary = (event: InputEvent) => {
+    if (event.target instanceof HTMLInputElement) {
+      setSalary(event.target.value);
+    }
   };
 
-  const { nettoSalary, pension, tax, grossSalary, insurance } =
-    getSalaryInfo(salary);
+  const { nettoSalary, pension, tax, grossSalary, insurance } = getSalaryInfo(
+    Number(salary),
+  );
 
   return (
     <div className="Calculator">

src/components/utils.js → src/components/utils.ts

@@ -3,18 +3,26 @@ const currencyFormatter = new Intl.NumberFormat("ru-KZ", {
   currency: "KZT",
 });
 
-export const getPension = (nettoSalary, minSalary) =>
+export const getPension = (nettoSalary: number, minSalary: number) =>
   nettoSalary * 0.1 < minSalary * 75 ? nettoSalary * 0.1 : minSalary * 75;
 
-export const getTax = (nettoSalary, minSalary, pension) =>
+export const getTax = (
+  nettoSalary: number,
+  minSalary: number,
+  pension: number,
+) =>
   nettoSalary === minSalary ? 0 : (nettoSalary - pension - minSalary) * 0.1;
 
-export const getGrossSalary = (nettoSalary, pension, tax) =>
-  nettoSalary - pension - tax;
+export const getGrossSalary = (
+  nettoSalary: number,
+  pension: number,
+  tax: number,
+) => nettoSalary - pension - tax;
 
-export const getInsurance = (salary) => salary * 0.01;
+export const getInsurance = (salary: number) => salary * 0.01;
 
-export const getSalaryInfo = (salary) => {
+// TODO: fix calculation and cover with tests
+export const getSalaryInfo = (salary: number) => {
   const minSalary = 70000;
   if (salary <= minSalary) {
     return { nettoSalary: salary, pension: 0, tax: 0, grossSalary: salary };
@@ -29,4 +37,4 @@ export const getSalaryInfo = (salary) => {
   return { nettoSalary, pension, tax, grossSalary, insurance };
 };
 
-export const formatCurrency = (number) => currencyFormatter.format(number);
+export const formatCurrency = (num: number) => currencyFormatter.format(num);

src/index.tsx

@@ -7,4 +7,4 @@ export function App() {
   return <Calculator />;
 }
 
-render(<App />, document.getElementById("app"));
+render(<App />, document.getElementById("app")!);

tsconfig.json

@@ -7,6 +7,7 @@
     "allowJs": true,
     "checkJs": true,
     "jsx": "react-jsx",
+    "strict": true,
     "jsxImportSource": "preact"
   },
   "include": ["node_modules/vite/client.d.ts", "**/*"]