Files and sharing

function downloadCsv(rows: string[][], filename = 'payments.csv') {
  const csv = rows.map((r) => r.map((c) => `"${c.replaceAll('"', '""')}"`).join(',')).join('\n')
  const blob = new Blob([csv], { type: 'text/csv;charset=utf-8' })
  const url = URL.createObjectURL(blob)

  const a = document.createElement('a')
  a.href = url
  a.download = filename
  document.body.appendChild(a)
  a.click()
  a.remove()

  setTimeout(() => URL.revokeObjectURL(url), 0)
}

async function shareResult(url: string) {
  if (!navigator.share) return false

  try {
    await navigator.share({ title: 'My result', url })
    return true
  } catch (err) {
    // The user closing the sheet rejects with AbortError. That is not a failure.
    if (err instanceof DOMException && err.name === 'AbortError') return false
    throw err
  }
}