import { authStore } from '$lib/stores/auth.js';
import { get } from 'svelte/store';

/**
 * @typedef {import('./types.js').APIResponse} APIResponse
 * @typedef {import('./types.js').AuthTokens} AuthTokens
 */

export const API_BASE = import.meta.env.VITE_API_URL || 'http://localhost:8080';

/**
 * Make authenticated API request
 * @template T
 * @param {string} endpoint
 * @param {RequestInit} [options]
 * @returns {Promise<T>}
 */
export async function apiRequest(endpoint, options = {}) {
	const auth = get(authStore);
	
	const headers = {
		'Content-Type': 'application/json',
		...options.headers
	};
	
	if (auth.accessToken) {
		headers['Authorization'] = `Bearer ${auth.accessToken}`;
	}
	
	try {
		const response = await fetch(`${API_BASE}${endpoint}`, {
			...options,
			headers
		});
		
		if (response.status === 401 && auth.refreshToken) {
			const refreshed = await refreshAccessToken(auth.refreshToken);
			if (refreshed) {
				headers['Authorization'] = `Bearer ${refreshed.access_token}`;
				return apiRequest(endpoint, { ...options, headers });
			}
		}
		
		if (!response.ok) {
			throw new Error(`HTTP ${response.status}: ${response.statusText}`);
		}
		
		const result = await response.json();
		
		if (!result.success) {
			throw new Error(result.error || 'Unknown error');
		}
		
		return result.data;
	} catch (error) {
		console.error(`API Error [${endpoint}]:`, error);
		throw error;
	}
}

/**
 * Refresh access token
 * @param {string} refreshToken
 * @returns {Promise<AuthTokens|null>}
 */
async function refreshAccessToken(refreshToken) {
	try {
		const response = await fetch(`${API_BASE}/auth/refresh`, {
			method: 'POST',
			headers: { 'Content-Type': 'application/json' },
			body: JSON.stringify({ refresh_token: refreshToken })
		});
		
		if (!response.ok) return null;
		
		const result = await response.json();
		if (result.success) {
			authStore.setTokens(result.data);
			return result.data;
		}
		
		return null;
	} catch {
		return null;
	}
}