const assert = require('node:assert/strict');
const path = require('node:path');

class FakeElement {
    constructor(id = '') {
        this.id = id;
        this.value = id === 'task' ? 'detect' : '';
        this.checked = false;
        this.disabled = false;
        this.style = {};
        this.children = [];
        this.listeners = {};
        this.className = '';
        this.textContent = '';
        this.scrollTop = 0;
        this.scrollHeight = 0;
        this.classList = {
            add() {},
            remove() {},
            contains() { return false; }
        };
    }

    addEventListener(name, handler) {
        this.listeners[name] = handler;
    }

    appendChild(child) {
        this.children.push(child);
        this.lastElementChild = child;
        return child;
    }

    getContext() {
        return {};
    }

    remove() {}

    set innerHTML(value) {
        this._innerHTML = value;
        this.children = [];
    }

    get innerHTML() {
        return this._innerHTML || '';
    }
}

const elements = new Map();
const element = id => {
    if (!elements.has(id)) elements.set(id, new FakeElement(id));
    return elements.get(id);
};

let domReady;
global.document = {
    addEventListener(name, handler) {
        if (name === 'DOMContentLoaded') domReady = handler;
    },
    querySelectorAll() {
        return [];
    },
    getElementById: element,
    createElement() {
        return new FakeElement();
    },
    head: new FakeElement('head'),
    body: new FakeElement('body')
};

const storage = new Map();
global.localStorage = {
    getItem(key) { return storage.has(key) ? storage.get(key) : null; },
    setItem(key, value) { storage.set(key, value); },
    removeItem(key) { storage.delete(key); }
};
global.confirm = () => true;
global.window = {location: {protocol: 'http:', host: '127.0.0.1:8000'}};

class FakeChart {
    static instances = [];

    constructor(_context, config) {
        this.data = config.data;
        this.options = config.options;
        FakeChart.instances.push(this);
    }

    destroy() {}
    update() {}
}
global.Chart = FakeChart;

class FakeWebSocket {
    static instances = [];

    constructor(url) {
        this.url = url;
        FakeWebSocket.instances.push(this);
    }
}
global.WebSocket = FakeWebSocket;

const response = (ok, data) => ({
    ok,
    async json() { return data; }
});
global.fetch = async url => {
    if (url === '/api/datasets' || url === '/api/models' || url === '/api/sessions') {
        return response(true, []);
    }
    if (url === '/api/sessions/last_run') return response(false, {});
    if (url === '/api/config/defaults') {
        return response(true, {
            dataset: 'coco8.yaml',
            model: 'yolo11n.pt',
            task: 'detect',
            workers: 8,
            patience: 100,
            augmentation: {enabled: true, close_mosaic: 10},
            mlflow: {enabled: false},
            split: {enabled: false}
        });
    }
    return response(false, {});
};

require(path.resolve(__dirname, '../src/yolo_webui/static/app.js'));

async function flushPromises() {
    await new Promise(resolve => setImmediate(resolve));
    await new Promise(resolve => setImmediate(resolve));
}

(async () => {
    assert.equal(typeof domReady, 'function');
    domReady();
    await flushPromises();

    element('workers').value = '0';
    element('patience').value = '0';
    element('close-mosaic').value = '0';
    element('auto-augment').value = 'none';
    element('config-form').listeners.input();
    const savedConfig = JSON.parse(storage.get('draft_config'));
    assert.equal(savedConfig.workers, 0);
    assert.equal(savedConfig.patience, 0);
    assert.equal(savedConfig.augmentation.close_mosaic, 0);
    assert.equal(savedConfig.augmentation.auto_augment, 'none');

    assert.equal(FakeWebSocket.instances.length, 2);
    const socket = FakeWebSocket.instances[0];
    socket.onmessage({
        data: JSON.stringify({
            type: 'init',
            status: 'idle',
            logs: [],
            metrics: [
                {epoch: 1, mAP50: 0.5},
                {epoch: 2, loss: 0.2}
            ]
        })
    });

    const chart = FakeChart.instances.at(-1);
    assert.deepEqual(chart.data.labels, [1, 2]);
    assert.deepEqual(chart.data.datasets.map(item => item.label), ['mAP50', 'loss']);
    assert.deepEqual(chart.data.datasets[0].data, [0.5, null]);
    assert.deepEqual(chart.data.datasets[1].data, [null, 0.2]);
})().catch(error => {
    console.error(error);
    process.exitCode = 1;
});