const form = document.querySelector('#analysis-form');
const button = document.querySelector('#analyze-button');
const errorBox = document.querySelector('#error-message');
const results = document.querySelector('#dashboard');

function expandHome(path) {
  return path.trim();
}

function render(data) {
  document.querySelectorAll('[data-field]').forEach((element) => {
    const value = data[element.dataset.field];
    element.textContent = value ?? '—';
  });
  const score = data.score;
  document.querySelector('#health-score').textContent = score == null ? '—' : `${score}%`;
  document.querySelector('#score-ring').style.setProperty('--score', score ?? 0);
  document.querySelector('#health-message').textContent = score == null
    ? 'Not enough data yet'
    : score >= 95 ? 'Looking excellent' : score >= 80 ? 'A few things need attention' : 'Review recommended';
  document.querySelector('#score-basis').textContent = data.score_basis;
  document.querySelector('#analysis-time').textContent = `Completed ${new Date().toLocaleTimeString([], {hour: '2-digit', minute: '2-digit'})}`;
  results.hidden = false;
  results.scrollIntoView({behavior: 'smooth', block: 'start'});
}

form.addEventListener('submit', async (event) => {
  event.preventDefault();
  errorBox.hidden = true;
  button.disabled = true;
  button.querySelector('span').textContent = 'Analyzing safely…';
  const roots = document.querySelector('#reference-roots').value
    .split('\n').map((value) => value.trim()).filter(Boolean);
  try {
    const response = await fetch('/api/analyze', {
      method: 'POST',
      headers: {'Content-Type': 'application/json'},
      body: JSON.stringify({
        serato: expandHome(document.querySelector('#serato-path').value),
        music: expandHome(document.querySelector('#music-path').value),
        reference_roots: roots,
      }),
    });
    const data = await response.json();
    if (!response.ok) throw new Error(data.error || 'Analysis failed');
    render(data);
  } catch (error) {
    errorBox.textContent = error.message;
    errorBox.hidden = false;
  } finally {
    button.disabled = false;
    button.querySelector('span').textContent = 'Analyze library';
  }
});