// Юнит-тесты слоя 2 (фронт): putToVm + uploadViaVM с пофайловым транзитом.
// Запуск: node --test tests/test_upload_layer2.test.mjs

import test from 'node:test';
import assert from 'node:assert/strict';

// Полифилл File/Blob при необходимости
if (typeof globalThis.File === 'undefined') {
  globalThis.File = class File extends Blob {
    constructor(parts, name, opts) {
      super(parts, opts);
      this.name = name;
      this.lastModified = (opts && opts.lastModified) || Date.now();
    }
  };
}

import { putToVm } from '../upload/frontend/upload/put_to_vm.js';
import { uploadViaVM } from '../upload/frontend/upload/upload_via_vm.js';

const tick = () => new Promise(r => setTimeout(r, 0));

// Мок XMLHttpRequest
let lastXHR = null;
class FakeXHR {
  constructor() {
    this.upload = {};
    this.status = 0;
    this.timeout = 0;
    this.onload = null;
    this.onerror = null;
    this.ontimeout = null;
    this.onabort = null;
    this.method = null;
    this.url = null;
    this.body = null;
    this.aborted = false;
    lastXHR = this;
  }
  open(method, url) { this.method = method; this.url = url; }
  send(body) { this.body = body; }
  abort() {
    this.aborted = true;
    if (this.onabort) this.onabort();
  }
}
globalThis.XMLHttpRequest = FakeXHR;

// Мок fetch
let fetchCalls = [];
function installFetch(handler) {
  fetchCalls = [];
  globalThis.fetch = async (url, opts) => {
    fetchCalls.push({ url, opts });
    return handler(url, opts);
  };
}

test('putToVm: успешная отправка', async () => {
  const f = new File(['test-content'], 'doc.pdf');
  const p = putToVm(f, 'https://vm-buffer/token_0');
  lastXHR.status = 200;
  lastXHR.onload();
  await p;
  assert.equal(lastXHR.method, 'PUT');
  assert.equal(lastXHR.url, 'https://vm-buffer/token_0');
  assert.equal(lastXHR.body, f);
});

test('putToVm: ошибка HTTP статуса', async () => {
  const p = putToVm(new File(['abc'], 'doc.pdf'), 'https://vm-buffer/token_0');
  lastXHR.status = 502;
  lastXHR.statusText = 'Bad Gateway';
  lastXHR.onload();
  await assert.rejects(p, /HTTP 502/);
});

test('putToVm: сетевая ошибка', async () => {
  const p = putToVm(new File(['abc'], 'doc.pdf'), 'https://vm-buffer/token_0');
  lastXHR.onerror();
  await assert.rejects(p, /Сетевая ошибка/);
});

test('putToVm: таймаут', async () => {
  const p = putToVm(new File(['abc'], 'doc.pdf'), 'https://vm-buffer/token_0');
  lastXHR.ontimeout();
  await assert.rejects(p, /Таймаут/);
});

test('putToVm: прерывание через AbortSignal', async () => {
  const ac = new AbortController();
  const p = putToVm(new File(['abc'], 'doc.pdf'), 'https://vm-buffer/token_0', { signal: ac.signal });
  ac.abort();
  await assert.rejects(p, (err) => err.name === 'AbortError');
  assert.equal(lastXHR.aborted, true);
});

test('uploadViaVM: пофайловый транзит (N файлов -> N PUT + N upload_refs)', async () => {
  let callCount = 0;
  installFetch(async (url, opts) => {
    callCount++;
    const body = JSON.parse(opts.body);
    return {
      ok: true,
      json: async () => ({
        ok: true,
        session: body.session || 'created-sid-1',
        count: callCount,
      }),
    };
  });

  const files = [
    new File(['hello'], 'first.txt'),
    new File(['world-data'], 'second.pdf'),
  ];

  const statuses = [];
  const completed = [];

  const p = uploadViaVM(files, {
    vmUploadUrl: 'https://vm-buffer/upload/',
    backendUploadUrl: '/api/upload_refs',
    onFileStatus: (idx, status) => statuses.push({ idx, status }),
    onFileComplete: (info) => completed.push(info),
  });

  // Файл 1: завершаем PUT
  await tick();
  assert.equal(lastXHR.method, 'PUT');
  assert.ok(lastXHR.url.startsWith('https://vm-buffer/upload/'));
  lastXHR.status = 201;
  lastXHR.onload();

  // Файл 2: завершаем PUT
  await tick();
  assert.equal(lastXHR.method, 'PUT');
  assert.ok(lastXHR.url.startsWith('https://vm-buffer/upload/'));
  lastXHR.status = 201;
  lastXHR.onload();

  const res = await p;
  assert.equal(res.ok, true);
  assert.equal(res.session, 'created-sid-1');
  assert.equal(res.count, 2);

  // Проверяем, что было РОВНО 2 вызова fetch (/api/upload_refs), по одному на каждый файл
  assert.equal(fetchCalls.length, 2);

  const call1Body = JSON.parse(fetchCalls[0].opts.body);
  assert.equal(call1Body.files.length, 1);
  assert.equal(call1Body.files[0].name, 'first.txt');

  const call2Body = JSON.parse(fetchCalls[1].opts.body);
  assert.equal(call2Body.files.length, 1);
  assert.equal(call2Body.files[0].name, 'second.pdf');
  // Сессия, созданная на 1 шаге, проброшена во 2 шаг
  assert.equal(call2Body.session, 'created-sid-1');

  assert.equal(completed.length, 2);
  assert.equal(completed[0].name, 'first.txt');
  assert.equal(completed[1].name, 'second.pdf');
});

test('uploadViaVM: поддержка формата FilePicker.getFiles() ({name, size, file, path})', async () => {
  installFetch(async (url, opts) => {
    return {
      ok: true,
      json: async () => ({ ok: true, session: 'sid-p', count: 1 }),
    };
  });

  const pickerFiles = [
    {
      name: 'archive_doc.txt',
      size: 42,
      file: new File(['x'.repeat(42)], 'archive_doc.txt'),
      path: 'folder/archive_doc.txt',
    },
  ];

  const p = uploadViaVM(pickerFiles, {
    vmUploadUrl: 'https://vm-buffer/upload/',
  });

  await tick();
  lastXHR.status = 200;
  lastXHR.onload();

  const res = await p;
  assert.equal(res.ok, true);
  assert.equal(res.count, 1);

  const body = JSON.parse(fetchCalls[0].opts.body);
  assert.equal(body.files[0].name, 'archive_doc.txt');
  assert.equal(body.files[0].size, 42);
});

test('uploadViaVM: обработка ошибки PUT', async () => {
  installFetch(async () => ({ ok: true, json: async () => ({ ok: true }) }));

  const files = [new File(['bad'], 'err.txt')];
  const p = uploadViaVM(files, {
    vmUploadUrl: 'https://vm-buffer/upload/',
  });

  await tick();
  lastXHR.onerror();

  const res = await p;
  assert.equal(res.ok, false);
  assert.ok(res.error.includes('Ошибка отправки файла'));
  assert.equal(fetchCalls.length, 0); // POST не вызывался
});

test('uploadViaVM: прерывание через signal', async () => {
  installFetch(async () => ({ ok: true, json: async () => ({ ok: true }) }));

  const ac = new AbortController();
  const files = [new File(['1'], 'f1.txt'), new File(['2'], 'f2.txt')];

  const p = uploadViaVM(files, {
    vmUploadUrl: 'https://vm-buffer/upload/',
    signal: ac.signal,
  });

  await tick();
  ac.abort();

  const res = await p;
  assert.equal(res.ok, false);
  assert.equal(res.aborted, true);
});

test('uploadViaVM: отмена после первого файла не начинает второй PUT', async () => {
  installFetch(async (url, opts) => ({
    ok: true,
    json: async () => ({ ok: true, session: 'partial-sid', count: 1 }),
  }));

  const ac = new AbortController();
  const statuses = [];
  const files = [new File(['first'], 'first.txt'), new File(['second'], 'second.txt')];
  const p = uploadViaVM(files, {
    vmUploadUrl: 'https://vm-buffer/upload/',
    signal: ac.signal,
    onFileStatus: (idx, status) => statuses.push({ idx, status }),
  });

  await tick();
  assert.equal(lastXHR.url.endsWith('_0'), true);
  lastXHR.status = 201;
  lastXHR.onload();
  ac.abort();
  const res = await p;

  assert.equal(res.ok, false);
  assert.equal(res.aborted, true);
  assert.equal(fetchCalls.length, 1);
  assert.equal(lastXHR.url.endsWith('_0'), true);
  assert.ok(statuses.some(({ idx, status }) => idx === 0 && status.includes('Доставлен')));
});