Update installing-a-dependency.md

docusaurus/docs/installing-a-dependency.md

@@ -1,18 +1,93 @@
----
-id: installing-a-dependency
-title: Installing a Dependency
----
+import React, { useState, useEffect, useMemo } from "react";
+// Single-file React component for an expense manager app
+// TailwindCSS is used for styling (assumes Tailwind is configured in the project).
+// Recharts is used for a small category pie chart. Install: `npm install recharts`
 
-The generated project includes React and ReactDOM as dependencies. It also includes a set of scripts used by Create React App as a development dependency. You may install other dependencies (for example, React Router) with `npm`:
 
-```sh
-npm install --save react-router-dom
-```
+import {
+PieChart,
+Pie,
+Cell,
+ResponsiveContainer,
+Tooltip as ReTooltip,
+} from "recharts";
 
-Alternatively you may use `yarn`:
 
-```sh
-yarn add react-router-dom
-```
+const DEFAULT_CATEGORIES = [
+"Ăn uống",
+"Di chuyển",
+"Nhà ở",
+"Giải trí",
+"Sức khỏe",
+"Thu nhập",
+"Khác",
+];
 
-This works for any library, not only `react-router-dom`.
+
+const COLORS = [
+"#4f46e5",
+"#06b6d4",
+"#f59e0b",
+"#ef4444",
+"#10b981",
+"#8b5cf6",
+"#374151",
+];
+
+
+const STORAGE_KEY = "expense_manager_data_v1";
+
+
+export default function ExpenseManager() {
+const [transactions, setTransactions] = useState([]);
+const [categories, setCategories] = useState(DEFAULT_CATEGORIES);
+
+
+const [form, setForm] = useState({
+type: "expense", // expense or income
+amount: "",
+category: DEFAULT_CATEGORIES[0],
+note: "",
+date: new Date().toISOString().slice(0, 10),
+});
+
+
+const [filterMonth, setFilterMonth] = useState(
+new Date().toISOString().slice(0, 7)
+);
+const [searchText, setSearchText] = useState("");
+
+
+// load from localStorage
+useEffect(() => {
+try {
+const raw = localStorage.getItem(STORAGE_KEY);
+if (raw) {
+const parsed = JSON.parse(raw);
+if (Array.isArray(parsed.transactions)) {
+setTransactions(parsed.transactions);
+}
+if (Array.isArray(parsed.categories)) {
+setCategories(parsed.categories);
+}
+}
+} catch (e) {
+console.error("Failed to load data", e);
+}
+}, []);
+
+
+// save to localStorage when transactions or categories change
+useEffect(() => {
+localStorage.setItem(
+STORAGE_KEY,
+JSON.stringify({ transactions, categories })
+);
+}, [transactions, categories]);
+
+
+function handleFormChange(e) {
+const { name, value } = e.target;
+setForm((f) => ({ ...f, [name]: value }));
+}
+}