/* -*- C++ -*-

  $Id: PolylineTool.cc,v 1.8 1999/02/05 08:19:59 sattler Exp $

  This file is part of KIllustrator.
  Copyright (C) 1998 Kai-Uwe Sattler (kus@iti.cs.uni-magdeburg.de)

  This program is free software; you can redistribute it and/or modify
  it under the terms of the GNU Library General Public License as
  published by  
  the Free Software Foundation; either version 2 of the License, or
  (at your option) any later version.

  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.
  
  You should have received a copy of the GNU Library General Public License
  along with this program; if not, write to the Free Software
  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

*/

#include <iostream.h>
#include "PolylineTool.h"
#include "PolylineTool.moc"
#include "GDocument.h"
#include "Canvas.h"
#include "Coord.h"
#include "GPolygon.h"
#include "CreatePolylineCmd.h"
#include "CreatePolygonCmd.h"
#include "AddLineSegmentCmd.h"
#include "CommandHistory.h"
#include <qkeycode.h>
#include <kapp.h>
#include <klocale.h>

PolylineTool::PolylineTool (CommandHistory* history) : Tool (history) {
  line = 0L;
  last = 0;
  newObj = true;
  points.setAutoDelete (true);
}

void PolylineTool::processEvent (QEvent* e, GDocument *doc, Canvas* canvas) {
  if (e->type () == Event_KeyPress) {
    QKeyEvent *ke = (QKeyEvent *) e;
    if (ke->key () == Key_Escape && line != 0L) {
      /*
       * Abort the last operation
       */
      if (newObj) {
        // for a new object we have to remove the last point
        line->removePoint (last);
        if (line->numOfPoints () >= 2) {
          // it's a regular line
          CreatePolylineCmd *cmd = new CreatePolylineCmd (doc, line);
          history->addCommand (cmd);
        }
        else {
          // no valid line - delete it
          doc->deleteObject (line);
          line = 0L;
        }
      }
      else {
        // remove the first point: it's equal to the last point
	// of the original line
	points.removeFirst ();
        // we have to remove the last added point
        line->removePoint (last);
        if (points.count () > 0) {
	  if (last != 0)
	    last = last - points.count ();
          AddLineSegmentCmd *cmd =  
            new AddLineSegmentCmd (doc, line, last, points);
          history->addCommand (cmd);
        }
      }
      if (line)
        doc->setLastObject (line);
      line = 0L; last = 0;
      emit operationDone ();
    }
  }
  else if (e->type () == Event_MouseButtonPress) {
    QMouseEvent *me = (QMouseEvent *) e;
    if (me->button () != LeftButton)
      return;

    float xpos = me->x (), ypos = me->y ();
    canvas->snapPositionToGrid (xpos, ypos);

    if (line != 0L) {
      // continue creation: add a new segment
      if (last != 0)
	last++;
    }
    else {
      newObj = true;
      points.clear ();

      GPolyline* obj = 0L;

      if (me->state () & ShiftButton) {
	// magnetic mode
	GObject *o = 0L;
	int idx = -1;
	if (doc->findNearestObject ("GPolyline", xpos, ypos, 
				    80, o, idx)) {
	  line = (GPolyline *) o;
	  last = (idx != 0 ? idx + 1 : idx);
	  newObj = false;
	}
      }
      else {
	// look for existing polylines with a point near the mouse pointer
	QList<GObject> olist;

	if (doc->findContainingObjects (xpos, ypos, olist)) {
	  QListIterator<GObject> it (olist);
	  while (it.current ()) {
	    if (it.current ()->isA ("GPolyline")) {
	      obj = (GPolyline *) it.current ();
	      break;
	    }
	    ++it;
	  }
	}
	if (obj && (last = obj->getNeighbourPoint (Coord (xpos, ypos))) != -1
	    && (last == 0 || last == (int) obj->numOfPoints () - 1)) {
	  line = obj; 
	  newObj = false;
	  if (last != 0)
	    // it's not the first point of the line, so update the
	    // index
	    last += 1;
	}
      }

      if (line == 0L) {
	// no polyline found, create a new one
	line = new GPolyline ();
	line->addPoint (0, Coord (xpos, ypos));
	last = 1;
	newObj = true;
	doc->insertObject (line);
      }
    }
    line->addPoint (last, Coord (xpos, ypos));
  }
  else if (e->type () == Event_MouseMove) {
    if (line == 0L)
      return;
    QMouseEvent *me = (QMouseEvent *) e;
    float xpos = me->x (), ypos = me->y ();
    canvas->snapPositionToGrid (xpos, ypos);

    line->setPoint (last, Coord (xpos, ypos));
  }
  else if (e->type () == Event_MouseButtonRelease) {
    if (line == 0L)
      return;
    QMouseEvent *me = (QMouseEvent *) e;
    float xpos = me->x (), ypos = me->y ();
    canvas->snapPositionToGrid (xpos, ypos);

    line->setPoint (last, Coord (xpos, ypos));

    if (! newObj)
      points.append (new Coord (xpos, ypos));

    if (me->button () == RightButton) {
      doc->unselectAllObjects ();

      if ((last > 0 && line->numOfPoints () >= 3 && 
	  line->getNeighbourPoint (Coord (xpos, ypos)) == 0) ||
	  (me->state () & ShiftButton)) {
	if (me->state () & ShiftButton) 
	    line->removePoint (line->numOfPoints () - 1, false);
	// the polyline is closed, so convert it into a polygon
	GPolygon* obj = new GPolygon (line->getPoints ());
	doc->deleteObject (line);
	if (obj->isValid ()) {
	  doc->insertObject (obj);
	  doc->setLastObject (obj);
	  CreatePolygonCmd *cmd = new CreatePolygonCmd (doc, obj);
	  history->addCommand (cmd);
	}
      }
      else {
	doc->setLastObject (line);
	if (newObj) {
	  if (! line->isValid ())
	    doc->deleteObject (line);
	  else {
	    CreatePolylineCmd *cmd = new CreatePolylineCmd (doc, line);
	    history->addCommand (cmd);
	  }
	}
	else {
	  // remove the first point: it's equal to the last point
	  // of the original line
	  points.removeFirst ();
	  if (last != 0)
	    last = last - points.count () + 1;
	  AddLineSegmentCmd *cmd =  
	    new AddLineSegmentCmd (doc, line, last, points);
	  history->addCommand (cmd);
	}
      }
      line = 0L; last = 0;
    }
  }
  return;
}

void PolylineTool::activate (GDocument* doc, Canvas*) {
  emit modeSelected (i18n ("Create Polyline"));
}

void PolylineTool::deactivate (GDocument*, Canvas*) {
  line = 0L;
  last = 0;
}