/*

 * Scala instance of Console plugin

 *

 * @author Makarius

 */

package isabelle.jedit

import console.{Console, Shell, Output}

import org.gjt.sp.jedit.jEdit

import org.gjt.sp.jedit.MiscUtilities

import java.io.{Writer, PrintWriter}

import scala.tools.nsc.{Interpreter, GenericRunnerSettings, NewLinePrintWriter, ConsoleWriter}

class Scala_Console extends Shell("Scala")

{

  private var interpreters = Map[Console, Interpreter]()

  private var global_console: Console = null

  private var global_out: Output = null

  private var global_err: Output = null

  private def report_error(str: String)

  {

    if (global_console == null || global_err == null) System.err.println(str)

    else global_err.print(global_console.getErrorColor, str)

  }

  private class Console_Writer extends Writer

  {

    def close {}

    def flush {}

    def write(cbuf: Array[Char], off: Int, len: Int)

    {

      if (len > 0) write(new String(cbuf.subArray(off, off + len)))

    }

    override def write(str: String)

    {

      if (global_out == null) System.out.println(str)

      else global_out.print(null, str)

    }

  }

  override def openConsole(console: Console)

  {

    val settings = new GenericRunnerSettings(report_error)

    val printer = new PrintWriter(new Console_Writer, true)

    interpreters += (console -> new Interpreter(settings, printer))

  }

  override def closeConsole(console: Console)

  {

    interpreters -= console

  }

  override def printPrompt(console: Console, out: Output)

	{

    out.print(console.getInfoColor, "scala> ")

	}

  override def execute(console: Console, input: String, out: Output, err: Output, command: String)

  {

    global_console = console

    global_out = out

    global_err = (if (err == null) out else err)

    interpreters(console).interpret(command)

    global_console = null

    global_out = null

    global_err = null

  }

}