src/Pure/PIDE/markup_tree.scala

+/*  Title:      Pure/PIDE/markup_tree.scala
+    Author:     Fabian Immler, TU Munich
+    Author:     Makarius
+
+Markup trees over nested / non-overlapping text ranges.
+*/
+
+package isabelle
+
+
+import javax.swing.tree.DefaultMutableTreeNode
+
+import scala.collection.immutable.SortedMap
+import scala.collection.mutable
+import scala.annotation.tailrec
+
+
+object Markup_Tree
+{
+  case class Node(val range: Text.Range, val info: Any)
+
+
+  /* branches sorted by quasi-order -- overlapping intervals appear as equivalent */
+
+  object Branches
+  {
+    type Entry = (Node, Markup_Tree)
+    type T = SortedMap[Node, Entry]
+
+    val empty = SortedMap.empty[Node, Entry](new scala.math.Ordering[Node]
+      {
+        def compare(x: Node, y: Node): Int = x.range compare y.range
+      })
+    def update(branches: T, entries: Entry*): T =
+      branches ++ entries.map(e => (e._1 -> e))
+    def make(entries: List[Entry]): T = update(empty, entries:_*)
+  }
+
+  val empty = new Markup_Tree(Branches.empty)
+}
+
+
+case class Markup_Tree(val branches: Markup_Tree.Branches.T)
+{
+  import Markup_Tree._
+
+  def + (new_node: Node): Markup_Tree =
+  {
+    // FIXME tune overlapping == branches && rest.isEmpty
+    val (overlapping, rest) =
+    {
+      val overlapping = new mutable.ListBuffer[Branches.Entry]
+      var rest = branches
+      while (rest.isDefinedAt(new_node)) {
+        overlapping += rest(new_node)
+        rest -= new_node
+      }
+      (overlapping.toList, rest)
+    }
+    overlapping match {
+      case Nil =>
+        new Markup_Tree(Branches.update(branches, new_node -> empty))
+
+      case List((node, subtree))
+        if node.range != new_node.range && (node.range contains new_node.range) =>
+        new Markup_Tree(Branches.update(branches, node -> (subtree + new_node)))
+
+      case _ if overlapping.forall(e => new_node.range contains e._1.range) =>
+        val new_tree = new Markup_Tree(Branches.make(overlapping))
+        new Markup_Tree(Branches.update(rest, new_node -> new_tree))
+
+      case _ => // FIXME split markup!?
+        System.err.println("Ignored overlapping markup: " + new_node); this
+    }
+  }
+
+  // FIXME depth-first with result markup stack
+  // FIXME projection to given range
+  def flatten(parent: Node): List[Node] =
+  {
+    val result = new mutable.ListBuffer[Node]
+    var offset = parent.range.start
+    for ((_, (node, subtree)) <- branches.iterator) {
+      if (offset < node.range.start)
+        result += new Node(Text.Range(offset, node.range.start), parent.info)
+      result ++= subtree.flatten(node)
+      offset = node.range.stop
+    }
+    if (offset < parent.range.stop)
+      result += new Node(Text.Range(offset, parent.range.stop), parent.info)
+    result.toList
+  }
+
+  def filter(pred: Node => Boolean): Markup_Tree =
+  {
+    val bs = branches.toList.flatMap(entry => {
+      val (_, (node, subtree)) = entry
+      if (pred(node)) List((node, (node, subtree.filter(pred))))
+      else subtree.filter(pred).branches.toList
+    })
+    new Markup_Tree(Branches.empty ++ bs)
+  }
+
+  def swing_tree(parent: DefaultMutableTreeNode)(swing_node: Node => DefaultMutableTreeNode)
+  {
+    for ((_, (node, subtree)) <- branches) {
+      val current = swing_node(node)
+      subtree.swing_tree(current)(swing_node)
+      parent.add(current)
+    }
+  }
+}
+