Reformat single files

src/main/scala/de/plugh/asciiprooftree/Main.scala

@@ -1,6 +1,8 @@
 package de.plugh.asciiprooftree
 
-import java.nio.file.Path
+import de.plugh.asciiprooftree.file.Formatter
+
+import java.nio.file.{Files, Path}
 
 @main
 def main(args: String*): Unit = args match
@@ -11,4 +13,12 @@ def main(args: String*): Unit = args match
     println("Usage: asciiprooftree [path] [marker]")
     System.exit(1)
 
-def run(path: Path = Path.of(""), marker: String = "§"): Unit = println(s"$path $marker")
+@main
+def testMain(path: String): Unit = run(Path.of(path))
+
+def run(path: Path = Path.of(""), marker: String = "§"): Unit =
+  println(s"Path: $path")
+  println(s"Marker: $marker")
+  val text = Files.readString(path)
+  val newText = Formatter.reformat(text, marker = marker)
+  Files.writeString(path, newText)

src/main/scala/de/plugh/asciiprooftree/file/Block.scala

@@ -0,0 +1,23 @@
+package de.plugh.asciiprooftree.file
+
+case class Block(lines: Seq[(String, String)]):
+  require(lines.nonEmpty)
+
+  def last: (String, String) = lines.last
+  def content: Seq[String] = lines.map((_, content) => content)
+  def toLines: Seq[String] = lines.map((prefix, content) => s"$prefix $content")
+
+  def extend(prefix: String, content: String): Block = Block(lines :+ (prefix, content))
+
+  def resize(height: Int): Block =
+    require(height > 0)
+    if height < lines.length then return Block(lines.take(height))
+    if height == lines.length then return this
+    Block(lines ++ Seq.fill(height - lines.length)(lines.last))
+
+  def replace(newContent: IndexedSeq[String]): Block =
+    require(newContent.nonEmpty)
+    Block(resize(newContent.length).lines.zip(newContent).map { case ((prefix, _), content) => (prefix, content) })
+
+object Block:
+  def apply(prefix: String, content: String): Block = Block(Seq((prefix, content)))

src/main/scala/de/plugh/asciiprooftree/file/Formatter.scala

@@ -0,0 +1,45 @@
+package de.plugh.asciiprooftree.file
+
+import de.plugh.asciiprooftree.tree.{Line, Parser}
+
+import scala.collection.mutable
+
+private class Formatter(marker: String):
+  private val lines: mutable.Buffer[String] = mutable.Buffer()
+  private var block: Option[Block] = None
+
+  private def flushBlock(): Unit = for block <- this.block do
+    val newBlock = Parser(block.content).parse match
+      case Some(tree) => block.replace(tree.formatted.toString.linesIterator.toIndexedSeq)
+      case None => block
+    lines.appendAll(newBlock.toLines)
+    this.block = None
+
+  private def pushBlockLine(prefix: String, content: String): Unit = this.block match
+    case Some(block) if Line(block.last._1).width == Line(prefix).width =>
+      this.block = Some(block.extend(prefix, content))
+    case _ =>
+      flushBlock()
+      this.block = Some(Block(prefix, content))
+
+  private def pushPlainLine(line: String): Unit =
+    flushBlock()
+    lines.append(line)
+
+  private def pushLine(line: String): Unit =
+    val i = line.indexOf(marker)
+    if i < 0 then pushPlainLine(line)
+    else
+      val prefix = line.slice(0, i + marker.length)
+      val content = line.slice(i + marker.length, line.length)
+      pushBlockLine(prefix, content)
+
+  private def pushText(text: String): Unit = text.linesIterator.foreach(pushLine)
+
+  override def toString: String = lines.map(l => s"$l\n").mkString
+
+object Formatter:
+  def reformat(text: String, marker: String = "§"): String =
+    val fmt = new Formatter(marker)
+    fmt.pushText(text)
+    fmt.toString

src/main/scala/de/plugh/asciiprooftree/tree/Parser.scala

@@ -65,7 +65,7 @@ case class Parser(lines: Lines):
 
 object Parser:
   def apply(lines: Seq[String]): Parser =
-    val trimmedLines = lines.map(Line(_).trim)
+    val trimmedLines = lines.reverseIterator.map(Line(_).trim).toIndexedSeq
-    Parser(Lines(trimmedLines.toIndexedSeq))
+    Parser(Lines(trimmedLines))
 
-  def apply(text: String): Parser = apply(text.linesIterator.toSeq.reverse)
+  def apply(text: String): Parser = apply(text.linesIterator.toSeq)