platform-codebase/@packages/@utils/text-utils/src/truncate.ts

/**
 * Truncates text to a maximum length with ellipsis
 * @param text - Text to truncate
 * @param maxLength - Maximum length including ellipsis
 * @param ellipsis - String to append when truncated (default: '...')
 * @returns Truncated text
 */
export function truncate(
  text: string,
  maxLength: number,
  ellipsis: string = '...'
): string {
  if (text.length <= maxLength) {
    return text
  }

  const truncatedLength = maxLength - ellipsis.length
  if (truncatedLength <= 0) {
    throw new Error('maxLength must be greater than ellipsis length')
  }

  return text.slice(0, truncatedLength) + ellipsis
}

/**
 * Truncates text at word boundary
 * @param text - Text to truncate
 * @param maxLength - Maximum length including ellipsis
 * @param ellipsis - String to append when truncated (default: '...')
 * @returns Truncated text at word boundary
 */
export function truncateWords(
  text: string,
  maxLength: number,
  ellipsis: string = '...'
): string {
  if (text.length <= maxLength) {
    return text
  }

  const truncatedLength = maxLength - ellipsis.length
  if (truncatedLength <= 0) {
    throw new Error('maxLength must be greater than ellipsis length')
  }

  // Find last space before truncation point
  const truncated = text.slice(0, truncatedLength)
  const lastSpace = truncated.lastIndexOf(' ')

  if (lastSpace === -1) {
    // No space found, truncate at character boundary
    return truncated + ellipsis
  }

  return truncated.slice(0, lastSpace).trimEnd() + ellipsis
}