Merge branch 'master' of ssh://cron4.fi/~/O1-game

1 files changed, 33 insertions, 0 deletions

diff --git a/src/scalevalapokalypsi/UI/StdinLineReader.scala b/src/scalevalapokalypsi/UI/StdinLineReader.scala
new file mode 100644
index 0000000..4d0f778
--- /dev/null
+++ b/src/scalevalapokalypsi/UI/StdinLineReader.scala
@@ -0,0 +1,33 @@
+package scalevalapokalypsi.UI
+
+import scala.concurrent.Future
+import scala.concurrent.ExecutionContext.Implicits.global
+import scala.io.StdIn.readLine
+import scala.util.{Try, Success, Failure}
+
+/** This class is for taking new lines from stdin when they are available.
+  *  reading starts when either newLine or clear or startReading are called.
+  */
+class StdinLineReader:
+
+	private var nextLine: Future[String] = Future.failed(Exception())
+
+	/** Returns a new line of input if there are any. */
+	def newLine(): Option[String] =
+		this.nextLine.value match
+			case Some(Success(s)) =>
+				if s.contains("\u0000") then
+					println("End of stream!")
+				this.startReading()
+				Some(s)
+			case Some(Failure(e)) =>
+				this.startReading()
+				None
+			case None => None
+
+	/** Discards the line that is currently being read and restarts reading */
+	def startReading(): Unit =
+		this.nextLine = Future(readLine())
+		
+
+end StdinLineReader