scala/ScalaBook/chapter-10/src/main/scala/scalabook/path/WinPath.scala

package scalabook.path

sealed trait WinPath extends Path

class UNCPath(val fullName: String) extends WinPath {
  def isRoot = 2 == fullName.length
  def isUNC = true
  override def isAbsolute = true
  def isEmpty = false

  def name =
    fullName.substring(fullName.lastIndexOf('/') + 1)
  def relative = new UnixPath(fullName.substring(2))
  
  def parent = {
    if(isRoot)
      EmptyPath
    else
      fullName.lastIndexOf('/') match {
        case 1 => new UNCPath("//")
        case n => new UNCPath(fullName.substring(0, n))
      }
  }

  override def parts = {
    if(isRoot)
      "//" :: Nil
    else
      "//" :: fullName.substring(2).split('/').toList
  }

  def /(that: String) = Path.combine(this, that)
  def /(that: Path)   = Path.combine(this, that)
}

class DriveAbsPath(val fullName: String) extends WinPath {
  def isRoot = 3 == fullName.length
  def isUNC = false
  override def isAbsolute = true
  def isEmpty = false

  def name =
    if(isRoot)
      ""
    else
      fullName.substring(fullName.lastIndexOf('/') + 1)
  
  def relative = new UnixPath(fullName.substring(3))

  def parent = {
    if(isRoot)
      EmptyPath
    else
      fullName.lastIndexOf('/') match {
        case 2 => new DriveAbsPath(fullName.substring(0, 3))
        case n => new DriveAbsPath(fullName.substring(0, n))
      }
  }

  override def parts = {
    if(isRoot)
      fullName :: Nil
    else
      fullName.substring(0, 3) ::
        fullName.substring(3).split('/').toList
  }

  def /(that: String) = Path.combine(this, that)
  def /(that: Path)   = Path.combine(this, that)
}