import { pipeline, TextStreamer } from 'https://cdn.jsdelivr.net/npm/@huggingface/transformers@3.7.3';

// --- Configuration ---
const MODEL_ID = "onnx-community/gemma-3-270m-it-ONNX";
const SYSTEM_PROMPT = { role: "system", content: "You are a helpful assistant." };

// --- State ---
let generator = null;
let messages = [SYSTEM_PROMPT];
let isGenerating = false;
let currentDevice = 'cpu';

// --- DOM Elements ---
const chatContainer = document.getElementById('chat-container');
const chatForm = document.getElementById('chat-form');
const userInput = document.getElementById('user-input');
const sendBtn = document.getElementById('send-btn');
const statusBar = document.getElementById('status-bar');
const statusText = document.querySelector('.status-text');
const progressBar = document.getElementById('progress-bar');
const deviceSelect = document.getElementById('device-select');
const resetBtn = document.getElementById('reset-btn');

// --- Initialization ---
function checkWebGPU() {
    if (!navigator.gpu) {
        const gpuOption = deviceSelect.querySelector('option[value="webgpu"]');
        if (gpuOption) {
            gpuOption.disabled = true;
            gpuOption.textContent = "GPU (WebGPU not available)";
        }
    }
}
checkWebGPU();

// --- Pipeline Management ---
async function loadGenerator() {
    const selectedDevice = deviceSelect.value;
    
    // If we already have a generator and the device hasn't changed, return it
    if (generator && currentDevice