/*
* AfterCmd.java --
*
*	Implements the built-in "after" Tcl command.
*
* Copyright (c) 1997 Cornell University.
* Copyright (c) 1997 Sun Microsystems, Inc.
*
* See the file "license.terms" for information on usage and
* redistribution of this file, and for a DISCLAIMER OF ALL
* WARRANTIES.
* 
* Included in SQLite3 port to C# for use in testharness only;  2008 Noah B Hart
*
* RCS @(#) $Id: AfterCmd.java,v 1.2 2002/04/12 21:00:26 mdejong Exp $
*
*/
using System;
using System.Collections;


namespace tcl.lang
{

  /*
  * This class implements the built-in "after" command in Tcl.
  */

  class AfterCmd : Command
  {

    /*
    * The list of handler are stored as AssocData in the interp.
    */

    internal AfterAssocData assocData = null;

    /*
    * Valid command options.
    */

    private static readonly string[] validOpts = new string[] { "cancel", "idle", "info" };

    internal const int OPT_CANCEL = 0;
    internal const int OPT_IDLE = 1;
    internal const int OPT_INFO = 2;

    public TCL.CompletionCode cmdProc( Interp interp, TclObject[] argv )
    {
      int i;
      Notifier notifier = (Notifier)interp.getNotifier();
      Object info;

      if ( assocData == null )
      {
        /*
        * Create the "after" information associated for this
        * interpreter, if it doesn't already exist.
        */

        assocData = (AfterAssocData)interp.getAssocData( "tclAfter" );
        if ( assocData == null )
        {
          assocData = new AfterAssocData( this );
          interp.setAssocData( "tclAfter", assocData );
        }
      }

      if ( argv.Length < 2 )
      {
        throw new TclNumArgsException( interp, 1, argv, "option ?arg arg ...?" );
      }

      /*
      * First lets see if the command was passed a number as the first argument.
      */

      bool isNumber = false;
      int ms = 0;

      if ( argv[1].InternalRep is TclInteger )
      {
        ms = TclInteger.get( interp, argv[1] );
        isNumber = true;
      }
      else
      {
        string s = argv[1].ToString();
        if ( ( s.Length > 0 ) && ( System.Char.IsDigit( s[0] ) ) )
        {
          ms = TclInteger.get( interp, argv[1] );
          isNumber = true;
        }
      }

      if ( isNumber )
      {
        if ( ms < 0 )
        {
          ms = 0;
        }
        if ( argv.Length == 2 )
        {
          /*
          * Sleep for at least the given milliseconds and return.
          */

          long endTime = System.DateTime.Now.Ticks / 10000 + ms;
          while ( true )
          {
            try
            {
              System.Threading.Thread.Sleep( ms );
              return TCL.CompletionCode.RETURN;
            }
            catch ( System.Threading.ThreadInterruptedException e )
            {
              /*
              * We got interrupted. Sleep again if we havn't slept
              * long enough yet.
              */

              long sysTime = System.DateTime.Now.Ticks / 10000;
              if ( sysTime >= endTime )
              {
                return TCL.CompletionCode.RETURN;
              }
              ms = (int)( endTime - sysTime );
              continue;
            }
          }
        }

        TclObject cmd = getCmdObject( argv );
        cmd.preserve();

        assocData.lastAfterId++;
        TimerInfo timerInfo = new TimerInfo( this, notifier, ms );
        timerInfo.interp = interp;
        timerInfo.command = cmd;
        timerInfo.id = assocData.lastAfterId;

        assocData.handlers.Add( timerInfo );

        interp.setResult( "after#" + timerInfo.id );

        return TCL.CompletionCode.RETURN;
      }

      /*
      * If it's not a number it must be a subcommand.
      */

      int index;

      try
      {
        index = TclIndex.get( interp, argv[1], validOpts, "option", 0 );
      }
      catch ( TclException e )
      {
        throw new TclException( interp, "bad argument \"" + argv[1] + "\": must be cancel, idle, info, or a number" );
      }

      switch ( index )
      {

        case OPT_CANCEL:
          if ( argv.Length < 3 )
          {
            throw new TclNumArgsException( interp, 2, argv, "id|command" );
          }

          TclObject arg = getCmdObject( argv );
          arg.preserve();

          /*
          * Search the timer/idle handler by id or by command.
          */

          info = null;
          for ( i = 0; i < assocData.handlers.Count; i++ )
          {
            Object obj = assocData.handlers[i];
            if ( obj is TimerInfo )
            {
              TclObject cmd = ( (TimerInfo)obj ).command;

              if ( ( cmd == arg ) || cmd.ToString().Equals( arg.ToString() ) )
              {
                info = obj;
                break;
              }
            }
            else
            {
              TclObject cmd = ( (IdleInfo)obj ).command;

              if ( ( cmd == arg ) || cmd.ToString().Equals( arg.ToString() ) )
              {
                info = obj;
                break;
              }
            }
          }
          if ( info == null )
          {

            info = getAfterEvent( arg.ToString() );
          }
          arg.release();

          /*
          * Cancel the handler.
          */

          if ( info != null )
          {
            if ( info is TimerInfo )
            {
              ( (TimerInfo)info ).cancel();
              ( (TimerInfo)info ).command.release();
            }
            else
            {
              ( (IdleInfo)info ).cancel();
              ( (IdleInfo)info ).command.release();
            }

            SupportClass.VectorRemoveElement( assocData.handlers, info );
          }
          break;


        case OPT_IDLE:
          if ( argv.Length < 3 )
          {
            throw new TclNumArgsException( interp, 2, argv, "script script ..." );
          }

          TclObject cmd2 = getCmdObject( argv );
          cmd2.preserve();
          assocData.lastAfterId++;

          IdleInfo idleInfo = new IdleInfo( this, notifier );
          idleInfo.interp = interp;
          idleInfo.command = cmd2;
          idleInfo.id = assocData.lastAfterId;

          assocData.handlers.Add( idleInfo );

          interp.setResult( "after#" + idleInfo.id );
          break;


        case OPT_INFO:
          if ( argv.Length == 2 )
          {
            /*
            * No id is given. Return a list of current after id's.
            */

            TclObject list = TclList.newInstance();
            for ( i = 0; i < assocData.handlers.Count; i++ )
            {
              int id;
              Object obj = assocData.handlers[i];
              if ( obj is TimerInfo )
              {
                id = ( (TimerInfo)obj ).id;
              }
              else
              {
                id = ( (IdleInfo)obj ).id;
              }
              TclList.append( interp, list, TclString.newInstance( "after#" + id ) );
            }
            interp.resetResult();
            interp.setResult( list );
            return TCL.CompletionCode.RETURN;
          }
          if ( argv.Length != 3 )
          {
            throw new TclNumArgsException( interp, 2, argv, "?id?" );
          }

          /*
          * Return command and type of the given after id.
          */


          info = getAfterEvent( argv[2].ToString() );
          if ( info == null )
          {

            throw new TclException( interp, "event \"" + argv[2] + "\" doesn't exist" );
          }
          TclObject list2 = TclList.newInstance();
          TclList.append( interp, list2, ( ( info is TimerInfo ) ? ( (TimerInfo)info ).command : ( (IdleInfo)info ).command ) );
          TclList.append( interp, list2, TclString.newInstance( ( info is TimerInfo ) ? "timer" : "idle" ) );

          interp.resetResult();
          interp.setResult( list2 );
          break;
      }
      return TCL.CompletionCode.RETURN;
    }
    private TclObject getCmdObject( TclObject[] argv )
    // Argument list passed to the "after" command.
    {
      if ( argv.Length == 3 )
      {
        return argv[2];
      }
      else
      {
        TclObject cmd = TclString.newInstance( Util.concat( 2, argv.Length - 1, argv ) );
        return cmd;
      }
    }
    private Object getAfterEvent( string inString )
    // Textual identifier for after event, such
    // as "after#6".
    {
      if ( !inString.StartsWith( "after#" ) )
      {
        return null;
      }

      StrtoulResult res = Util.strtoul( inString, 6, 10 );
      if ( res.errno != 0 )
      {
        return null;
      }

      for ( int i = 0; i < assocData.handlers.Count; i++ )
      {
        Object obj = assocData.handlers[i];
        if ( obj is TimerInfo )
        {
          if ( ( (TimerInfo)obj ).id == res.value )
          {
            return obj;
          }
        }
        else
        {
          if ( ( (IdleInfo)obj ).id == res.value )
          {
            return obj;
          }
        }
      }

      return null;
    }
    internal class AfterAssocData : AssocData
    {
      public AfterAssocData( AfterCmd enclosingInstance )
      {
        InitBlock( enclosingInstance );
      }
      private void InitBlock( AfterCmd enclosingInstance )
      {
        this.enclosingInstance = enclosingInstance;
        handlers = new ArrayList( 10 );
      }
      private AfterCmd enclosingInstance;
      public AfterCmd Enclosing_Instance
      {
        get
        {
          return enclosingInstance;
        }

      }

      /*
      * The set of handlers created but not yet fired.
      */

      internal ArrayList handlers;

      /*
      * Timer identifier of most recently created timer.	
      */

      internal int lastAfterId = 0;

      public void disposeAssocData( Interp interp )
      // The interpreter in which this AssocData
      // instance is registered in.
      {
        for ( int i = Enclosing_Instance.assocData.handlers.Count - 1; i >= 0; i-- )
        {
          Object info = Enclosing_Instance.assocData.handlers[i];
          Enclosing_Instance.assocData.handlers.RemoveAt( i );
          if ( info is TimerInfo )
          {
            ( (TimerInfo)info ).cancel();
            ( (TimerInfo)info ).command.release();
          }
          else
          {
            ( (IdleInfo)info ).cancel();
            ( (IdleInfo)info ).command.release();
          }
        }
        Enclosing_Instance.assocData = null;
      }
    } // end AfterCmd.AfterAssocData

    internal class TimerInfo : TimerHandler
    {
      private void InitBlock( AfterCmd enclosingInstance )
      {
        this.enclosingInstance = enclosingInstance;
      }
      private AfterCmd enclosingInstance;
      public AfterCmd Enclosing_Instance
      {
        get
        {
          return enclosingInstance;
        }

      }

      /*
      * Interpreter in which the script should be executed.
      */

      internal Interp interp;

      /*
      * Command to execute when the timer fires.
      */

      internal TclObject command;

      /*
      * Integer identifier for command;  used to cancel it.
      */

      internal int id;

      internal TimerInfo( AfterCmd enclosingInstance, Notifier n, int milliseconds )
        : base( n, milliseconds )
      {
        InitBlock( enclosingInstance );
      }
      public override void processTimerEvent()
      {
        try
        {
          SupportClass.VectorRemoveElement( Enclosing_Instance.assocData.handlers, this );
          interp.eval( command, TCL.EVAL_GLOBAL );
        }
        catch ( TclException e )
        {
          interp.addErrorInfo( "\n    (\"after\" script)" );
          interp.backgroundError();
        }
        finally
        {
          command.release();
          command = null;
        }
      }
    } // end AfterCmd.AfterInfo

    internal class IdleInfo : IdleHandler
    {
      private void InitBlock( AfterCmd enclosingInstance )
      {
        this.enclosingInstance = enclosingInstance;
      }
      private AfterCmd enclosingInstance;
      public AfterCmd Enclosing_Instance
      {
        get
        {
          return enclosingInstance;
        }

      }

      /*
      * Interpreter in which the script should be executed.
      */

      internal Interp interp;

      /*
      * Command to execute when the idle event fires.
      */

      internal TclObject command;

      /*
      * Integer identifier for command;  used to cancel it.
      */

      internal int id;

      internal IdleInfo( AfterCmd enclosingInstance, Notifier n )
        : base( n )
      {
        InitBlock( enclosingInstance );
      }
      public override void processIdleEvent()
      {
        try
        {
          SupportClass.VectorRemoveElement( Enclosing_Instance.assocData.handlers, this );
          interp.eval( command, TCL.EVAL_GLOBAL );
        }
        catch ( TclException e )
        {
          interp.addErrorInfo( "\n    (\"after\" script)" );
          interp.backgroundError();
        }
        finally
        {
          command.release();
          command = null;
        }
      }
    } // end AfterCmd.AfterInfo
  } // end AfterCmd
}