function escapeRegExp(string: string): string {
  return string.replace(/[.*+?^${}()|[\]\\]/g, '\\$&');
}

function sanitizeInput(text: string): string {
  return text?.replace(/</g, '&lt;').replace(/>/g, '&gt;').replace(/"/g, '&quot;');
}

export function highlightText(text: string, keyword: string): string {
  const safeText = sanitizeInput(text);
  const safeKeyword = sanitizeInput(keyword);
  if (!text || typeof text !== 'string') {
    return text;
  }
  if (!safeKeyword || typeof safeKeyword !== 'string') {
    return safeText;
  }

  const trimmedKeyword = safeKeyword.trim();
  if (!trimmedKeyword) {
    return safeText;
  }

  try {
    const regex = new RegExp(`(${escapeRegExp(trimmedKeyword)})`, 'gi');
    const parts = safeText.split(regex);

    if (parts.length === 1) {
      return safeText;
    }

    return parts
      .map((part, index) => {
        if (part.toLowerCase() === trimmedKeyword.toLowerCase()) {
          return `<span key=${index} class="highlight">${part}</span>`;
        }
        return part;
      })
      .join('');
  } catch (error) {
    console.warn('Error highlighting text:', error);
    return safeText;
  }
}