/* URL-tool flow: paste link → instant info → job → poll → download. */
(function () {
  'use strict';

  var panel = document.getElementById('tool-panel');
  if (!panel) return;
  var slug = panel.dataset.tool;

  var form = document.getElementById('tool-form');
  var urlInput = document.getElementById('url-input');
  var infoPanel = document.getElementById('info-panel');
  var statusFlow = document.getElementById('status-flow');
  var progressFill = document.getElementById('progress-fill');
  var resultPanel = document.getElementById('result-panel');
  var errorBox = document.getElementById('error-box');

  var pollTimer = null, currentJobId = null;

  function track(name) {
    try {
      navigator.sendBeacon &&
        navigator.sendBeacon('/api/events', new Blob([JSON.stringify({ name: name, tool: slug })], { type: 'application/json' }));
    } catch (e) {}
  }

  function showError(msg) { errorBox.textContent = msg; errorBox.hidden = false; track('tool_failure'); }

  function setStage(stage, progress) {
    statusFlow.hidden = false;
    document.querySelectorAll('.stages li').forEach(function (li) {
      li.classList.toggle('done', li.dataset.stage !== stage);
      li.classList.toggle('active', li.dataset.stage === stage);
    });
    if (typeof progress === 'number') progressFill.style.width = Math.max(6, progress) + '%';
  }

  form.addEventListener('submit', function (e) {
    e.preventDefault();
    hideError();
    resultPanel.classList.remove('show');

    fetch('/api/jobs', {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({ tool: slug, url: urlInput.value })
    })
      .then(function (r) { return r.json().then(function (j) { return { status: r.status, body: j }; }); })
      .then(function (res) {
        if (!res.ok) throw new Error(res.body.message || res.body.error || 'Request failed.');
        currentJobId = res.body.job_id;
        setStage('preparing', 8);
        poll();
      })
      .catch(function (err) { showError(err.message || 'Something went wrong. Please try again.'); });
  });

  function hideError() { errorBox.hidden = true; }

  function poll() {
    if (!currentJobId) return;
    fetch('/api/jobs/' + currentJobId)
      .then(function (r) { return r.json(); })
      .then(function (data) {
        if (!data.ok) throw new Error('lost');
        if (data.status === 'completed') { finish(data); return; }
        if (data.status === 'failed') { showError(data.message || 'This video could not be processed.'); return; }
        var stageMap = { preparing: 'preparing', fetching: 'fetching', processing: 'processing', converting: 'converting' };
        setStage(stageMap[data.stage] || 'processing', data.progress);
        pollTimer = setTimeout(poll, 1600);
      })
      .catch(function () { pollTimer = setTimeout(poll, 3200); });
  }

  function finish(data) {
    clearTimeout(pollTimer);
    setStage('complete', 100);
    resultPanel.innerHTML =
      '<div class="result-meta">' +
        '<span class="badge">Done</span>' +
        '<strong>' + escapeHtml(data.output_name || 'download') + '</strong>' +
        '<span>' + humanSize(data.output_size || 0) + '</span>' +
        '<a class="btn-primary" style="text-decoration:none;padding:.55rem 1.3rem;font-size:.95rem" href="' + data.download_url + '" download>Download</a>' +
      '</div>';
    resultPanel.classList.add('show');
  }

  function humanSize(bytes) {
    var u = ['B', 'KB', 'MB', 'GB'], i = 0;
    while (bytes >= 1024 && i < u.length - 1) { bytes /= 1024; i++; }
    return (Math.round(bytes * 10) / 10) + ' ' + u[i];
  }

  function escapeHtml(s) {
    var d = document.createElement('div');
    d.textContent = s;
    return d.innerHTML;
  }
})();