/* Title: Pure/PIDE/line.scala
Author: Makarius
Line-oriented text.
*/
package isabelle
import scala.annotation.tailrec
object Line
{
/* position */
object Position
{
val zero: Position = Position(0, 0)
}
sealed case class Position(line: Int, column: Int)
{
def line1: Int = line + 1
def column1: Int = column + 1
def print: String = line1.toString + ":" + column1.toString
def compare(that: Position): Int =
line compare that.line match {
case 0 => column compare that.column
case i => i
}
private def advance[A](iterator: Iterator[A], is_newline: A => Boolean): Position =
{
var l = line
var c = column
for (x <- iterator) {
if (is_newline(x)) { l += 1; c = 0 } else c += 1
}
Position(l, c)
}
def advance(text: String): Position =
if (text.isEmpty) this else advance[Char](text.iterator, _ == '\n')
def advance_codepoints(text: String): Position =
if (text.isEmpty) this else advance[Int](Codepoint.iterator(text), _ == 10)
}
/* range (right-open interval) */
sealed case class Range(start: Position, stop: Position)
{
if (start.compare(stop) > 0)
error("Bad line range: " + start.print + ".." + stop.print)
def print: String = start.print + ".." + stop.print
}
/* document with newline as separator (not terminator) */
object Document
{
val empty: Document = new Document("", Nil)
def apply(lines: List[Line]): Document =
if (lines.isEmpty) empty
else new Document(lines.mkString("", "\n", ""), lines)
def apply(text: String): Document =
if (text.contains('\r'))
apply(Library.cat_lines(Library.split_lines(text).map(Library.trim_line(_))))
else if (text == "") Document.empty
else new Document(text, Library.split_lines(text).map(Line(_)))
}
final class Document private(val text: String, val lines: List[Line])
{
override def toString: String = text
override def equals(that: Any): Boolean =
that match {
case other: Document => lines == other.lines
case _ => false
}
override def hashCode(): Int = lines.hashCode
private def position(advance: (Position, String) => Position, offset: Text.Offset): Position =
{
@tailrec def move(i: Text.Offset, lines_count: Int, lines_rest: List[Line]): Position =
{
lines_rest match {
case Nil => require(i == 0); Position(lines_count, 0)
case line :: ls =>
val n = line.text.length
if (ls.isEmpty || i <= n) advance(Position(lines_count, 0), line.text.substring(n - i))
else move(i - (n + 1), lines_count + 1, ls)
}
}
move(offset, 0, lines)
}
def position(i: Text.Offset): Position = position(_.advance(_), i)
def position_codepoints(i: Text.Offset): Position = position(_.advance_codepoints(_), i)
// FIXME codepoints
def offset(pos: Position): Option[Text.Offset] =
{
val l = pos.line
val c = pos.column
if (0 <= l && l < lines.length) {
val line_offset =
if (l == 0) 0
else (0 /: lines.take(l - 1))({ case (n, line) => n + line.text.length + 1 })
if (c <= lines(l).text.length) Some(line_offset + c) else None
}
else None
}
}
/* line text */
val empty: Line = new Line("")
def apply(text: String): Line = if (text == "") empty else new Line(text)
}
final class Line private(val text: String)
{
require(text.forall(c => c != '\r' && c != '\n'))
lazy val length_codepoints: Int = Codepoint.iterator(text).length
override def equals(that: Any): Boolean =
that match {
case other: Line => text == other.text
case _ => false
}
override def hashCode(): Int = text.hashCode
override def toString: String = text
}