opencode/packages/util/src/path.ts

export function getFilename(path: string | undefined) {
  if (!path) return ""
  const trimmed = path.replace(/[\/\\]+$/, "")
  const parts = trimmed.split(/[\/\\]/)
  return parts[parts.length - 1] ?? ""
}

export function getDirectory(path: string | undefined) {
  if (!path) return ""
  const trimmed = path.replace(/[\/\\]+$/, "")
  const parts = trimmed.split(/[\/\\]/)
  return parts.slice(0, parts.length - 1).join("/") + "/"
}

export function getFileExtension(path: string | undefined) {
  if (!path) return ""
  const parts = path.split(".")
  return parts[parts.length - 1]
}

export function getFilenameTruncated(path: string | undefined, maxLength: number = 20) {
  const filename = getFilename(path)
  if (filename.length <= maxLength) return filename
  const lastDot = filename.lastIndexOf(".")
  const name = lastDot <= 0 ? filename : filename.slice(0, lastDot)
  const ext = lastDot <= 0 ? "" : filename.slice(lastDot)
  const available = maxLength - ext.length - 1 // -1 for ellipsis
  if (available <= 0) return filename.slice(0, maxLength - 1) + "…"
  const start = Math.ceil(available / 2)
  const end = Math.floor(available / 2)
  return name.slice(0, start) + "…" + name.slice(-end) + ext
}