feat(frontend): introduced a working frontend prototype

7project/frontend/src/api.ts

@@ -0,0 +1,100 @@
+import { BACKEND_URL } from './config';
+
+export type LoginResponse = {
+  access_token: string;
+  token_type: string;
+};
+
+export type Category = {
+  id: number;
+  name: string;
+  description?: string | null;
+};
+
+export type Transaction = {
+  id: number;
+  amount: number;
+  description?: string | null;
+  category_ids: number[];
+};
+
+function getBaseUrl() {
+  const base = BACKEND_URL?.replace(/\/$/, '') || '';
+  return base || '';
+}
+
+function authHeaders() {
+  const token = localStorage.getItem('token');
+  return token ? { Authorization: `Bearer ${token}` } : {};
+}
+
+export async function login(email: string, password: string): Promise<void> {
+  const body = new URLSearchParams();
+  body.set('username', email);
+  body.set('password', password);
+
+  const res = await fetch(`${getBaseUrl()}/auth/jwt/login`, {
+    method: 'POST',
+    headers: {
+      'Content-Type': 'application/x-www-form-urlencoded',
+    },
+    body: body.toString(),
+  });
+  if (!res.ok) {
+    const text = await res.text();
+    throw new Error(text || 'Login failed');
+  }
+  const data: LoginResponse = await res.json();
+  localStorage.setItem('token', data.access_token);
+}
+
+export async function register(email: string, password: string, first_name?: string, last_name?: string): Promise<void> {
+  const res = await fetch(`${getBaseUrl()}/auth/register`, {
+    method: 'POST',
+    headers: { 'Content-Type': 'application/json' },
+    body: JSON.stringify({ email, password, first_name, last_name }),
+  });
+  if (!res.ok) {
+    const text = await res.text();
+    throw new Error(text || 'Registration failed');
+  }
+}
+
+export async function getCategories(): Promise<Category[]> {
+  const res = await fetch(`${getBaseUrl()}/categories/`, {
+    headers: { 'Content-Type': 'application/json', ...authHeaders() },
+  });
+  if (!res.ok) throw new Error('Failed to load categories');
+  return res.json();
+}
+
+export type CreateTransactionInput = {
+  amount: number;
+  description?: string;
+  category_ids?: number[];
+};
+
+export async function createTransaction(input: CreateTransactionInput): Promise<Transaction> {
+  const res = await fetch(`${getBaseUrl()}/transactions/create`, {
+    method: 'POST',
+    headers: { 'Content-Type': 'application/json', ...authHeaders() },
+    body: JSON.stringify(input),
+  });
+  if (!res.ok) {
+    const text = await res.text();
+    throw new Error(text || 'Failed to create transaction');
+  }
+  return res.json();
+}
+
+export async function getTransactions(): Promise<Transaction[]> {
+  const res = await fetch(`${getBaseUrl()}/transactions/`, {
+    headers: { 'Content-Type': 'application/json', ...authHeaders() },
+  });
+  if (!res.ok) throw new Error('Failed to load transactions');
+  return res.json();
+}
+
+export function logout() {
+  localStorage.removeItem('token');
+}