// @(#)root/gui:$Name:  $:$Id: TGSlider.cxx,v 1.3 2000/09/08 16:11:58 rdm Exp $
// Author: Fons Rademakers   14/01/98

/*************************************************************************
 * Copyright (C) 1995-2000, Rene Brun and Fons Rademakers.               *
 * All rights reserved.                                                  *
 *                                                                       *
 * For the licensing terms see $ROOTSYS/LICENSE.                         *
 * For the list of contributors see $ROOTSYS/README/CREDITS.             *
 *************************************************************************/
/**************************************************************************

    This source is based on Xclass95, a Win95-looking GUI toolkit.
    Copyright (C) 1996, 1997 David Barth, Ricky Ralston, Hector Peraza.

    Xclass95 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.

**************************************************************************/

//////////////////////////////////////////////////////////////////////////
//                                                                      //
// TGSlider, TGVSlider and TGHSlider                                    //
//                                                                      //
// Slider widgets allow easy selection out of a range.                  //
// Sliders can be either horizontal or vertical oriented and there is   //
// a choice of two different slider types and three different types     //
// of tick marks.                                                       //
//                                                                      //
// TGSlider is an abstract base class. Use the concrete TGVSlider and   //
// TGHSlider.                                                           //
//                                                                      //
// Dragging the slider will generate the event:                         //
// kC_VSLIDER, kSL_POS, slider id, position  (for vertical slider)      //
// kC_HSLIDER, kSL_POS, slider id, position  (for horizontal slider)    //
//                                                                      //
//////////////////////////////////////////////////////////////////////////

#include "TGSlider.h"
#include "TGPicture.h"

ClassImp(TGSlider)
ClassImp(TGVSlider)
ClassImp(TGHSlider)


//______________________________________________________________________________
TGSlider::TGSlider(const TGWindow *p, UInt_t w, UInt_t h, UInt_t type, Int_t id,
                   UInt_t options, ULong_t back)
   : TGFrame(p, w, h, options, back)
{
   // Slider constructor.

   fWidgetId    = id;
   fWidgetFlags = kWidgetWantFocus;
   fMsgWindow   = p;

   fType     = type;
   fScale    = 10;
   fDragging = kFALSE;
}

//______________________________________________________________________________
TGVSlider::TGVSlider(const TGWindow *p, UInt_t h, UInt_t type, Int_t id,
                     UInt_t options, ULong_t back) :
   TGSlider(p, kSliderWidth, h, type, id, options, back)
{
   // Create a vertical slider widget.

   if ((fType & kSlider1))
      fSliderPic = fClient->GetPicture("slider1h.xpm");
   else
      fSliderPic = fClient->GetPicture("slider2h.xpm");

   if (!fSliderPic)
      Error("TGVSlider", "slider?h.xpm not found");

   gVirtualX->GrabButton(fId, kAnyButton, kAnyModifier,
                    kButtonPressMask | kButtonReleaseMask |
                    kPointerMotionMask, kNone, kNone);

   // set initial values
   fPos = h/2; fVmin = 0; fVmax = h;
}

//______________________________________________________________________________
TGVSlider::~TGVSlider()
{
   // Delete vertical slider widget.

   if (fSliderPic) fClient->FreePicture(fSliderPic);
}

//______________________________________________________________________________
void TGVSlider::DoRedraw()
{
   // Redraw vertical slider widget.

   // cleanup the drawable
   gVirtualX->ClearWindow(fId);

   gVirtualX->DrawLine(fId, fgShadowGC, fWidth/2, 8, fWidth/2-1, 8);
   gVirtualX->DrawLine(fId, fgShadowGC, fWidth/2-1, 8, fWidth/2-1, fHeight-9);
   gVirtualX->DrawLine(fId, fgHilightGC, fWidth/2+1, 8, fWidth/2+1, fHeight-8);
   gVirtualX->DrawLine(fId, fgHilightGC, fWidth/2+1, fHeight-8, fWidth/2, fHeight-8);
   gVirtualX->DrawLine(fId, fgBlackGC, fWidth/2, 9, fWidth/2, fHeight-9);

   // check scale
   if (fScale == 1) fScale++;
   if (fScale * 2 > (int)fHeight) fScale = 0;
   if (fScale > 0 && !(fType & kScaleNo)) {
      int lines = ((int)fHeight-16) / fScale;
      int remain = ((int)fHeight-16) % fScale;
      for (int i = 0; i <= lines; i++) {
         int y = i * fScale + (i * remain) / lines;
         gVirtualX->DrawLine(fId, fgBlackGC, fWidth/2+8, y+7, fWidth/2+10, y+7);
         if ((fType & kSlider2) && (fType & kScaleBoth))
            gVirtualX->DrawLine(fId, fgBlackGC, fWidth/2-9, y+7, fWidth/2-11, y+7);
      }
   }
   if (fPos < fVmin) fPos = fVmin;
   if (fPos > fVmax) fPos = fVmax;

   // calc slider-picture position
   fRelPos = (((int)fHeight-16) * (fPos - fVmin)) / (fVmax - fVmin) + 8;
   if (fSliderPic) fSliderPic->Draw(fId, fgBckgndGC, fWidth/2-7, fRelPos-6);
}

//______________________________________________________________________________
Bool_t TGVSlider::HandleButton(Event_t *event)
{
   // Handle mouse button event in vertical slider.

   if (event->fType == kButtonPress) {
      if (event->fY >= fRelPos - 7 && event->fY <= fRelPos + 7) {
         // slider selected
         fDragging = kTRUE;
         fYp = event->fY - (fRelPos-7);
      } else {
         if (event->fCode == kButton1) {
            // scroll up or down
            int m = (fVmax - fVmin) / (fHeight-16);
            if (event->fY < fRelPos) {
               fPos -= ((m) ? m : 1);
            }
            if (event->fY > fRelPos) {
               fPos += ((m) ? m : 1);
            }
         } else if (event->fCode == kButton2) {
            // set absolute position
            fPos = ((fVmax - fVmin) * event->fY) / (fHeight-16) + fVmin;
         }
         SendMessage(fMsgWindow, MK_MSG(kC_VSLIDER, kSL_POS),
                     fWidgetId, fPos);
         fClient->ProcessLine(fCommand, MK_MSG(kC_VSLIDER, kSL_POS),
                              fWidgetId, fPos);
      }
      fClient->NeedRedraw(this);

      // last argument kFALSE forces all specified events to this window
      gVirtualX->GrabPointer(fId, kButtonPressMask | kButtonReleaseMask |
                             kPointerMotionMask, kNone, kNone,
                             kTRUE, kFALSE);
   } else {
      // ButtonRelease
      fDragging = kFALSE;
      gVirtualX->GrabPointer(0, 0, 0, 0, kFALSE);  // ungrab pointer
   }
   return kTRUE;
}

//______________________________________________________________________________
Bool_t TGVSlider::HandleMotion(Event_t *event)
{
   // Handle mouse motion event in vertical slider.

   if (fDragging) {
      int old = fPos;
      fPos = ((fVmax - fVmin) * (event->fY - fYp)) / ((int)fHeight-16) + fVmin;
      if (fPos > fVmax) fPos = fVmax;
      if (fPos < fVmin) fPos = fVmin;

      // check if position changed
      if (old != fPos) {
         fClient->NeedRedraw(this);
         SendMessage(fMsgWindow, MK_MSG(kC_VSLIDER, kSL_POS),
                     fWidgetId, fPos);
         fClient->ProcessLine(fCommand, MK_MSG(kC_VSLIDER, kSL_POS),
                              fWidgetId, fPos);
      }
   }
   return kTRUE;
}



//______________________________________________________________________________
 TGHSlider::TGHSlider(const TGWindow *p, UInt_t w, UInt_t type, Int_t id,
                     UInt_t options, ULong_t back) :
   TGSlider(p, w, kSliderHeight, type, id, options, back)
{
   // Create horizontal slider widget.

   if ((fType & kSlider1))
      fSliderPic = fClient->GetPicture("slider1v.xpm");
   else
      fSliderPic = fClient->GetPicture("slider2v.xpm");

   if (!fSliderPic)
      Error("TGHSlider", "slider?v.xpm not found");

   gVirtualX->GrabButton(fId, kAnyButton, kAnyModifier,
                    kButtonPressMask | kButtonReleaseMask |
                    kPointerMotionMask, kNone, kNone);

   // set initial values
   fPos = w/2; fVmin = 0; fVmax = w;
}

//______________________________________________________________________________
 TGHSlider::~TGHSlider()
{
   // Delete a horizontal slider widget.

  if (fSliderPic) fClient->FreePicture(fSliderPic);
}

//______________________________________________________________________________
 void TGHSlider::DoRedraw()
{
   // Redraw horizontal slider widget.

   // cleanup drawable
   gVirtualX->ClearWindow(fId);

   gVirtualX->DrawLine(fId, fgShadowGC, 8, fHeight/2, 8, fHeight/2-1);
   gVirtualX->DrawLine(fId, fgShadowGC, 8, fHeight/2-1, fWidth-9, fHeight/2-1);
   gVirtualX->DrawLine(fId, fgHilightGC, 8, fHeight/2+1, fWidth-8, fHeight/2+1);
   gVirtualX->DrawLine(fId, fgHilightGC, fWidth-8, fHeight/2+1, fWidth-8, fHeight/2);
   gVirtualX->DrawLine(fId, fgBlackGC, 9, fHeight/2, fWidth-9, fHeight/2);

   if (fScale == 1) fScale++;
   if (fScale * 2 > (int)fWidth) fScale = 0;
   if (fScale > 0 && !(fType & kScaleNo)) {
      int lines = ((int)fWidth-16) / fScale;
      int remain = ((int)fWidth-16) % fScale;
      for (int i = 0; i <= lines; i++) {
         int x = i * fScale + (i * remain) / lines;
         gVirtualX->DrawLine(fId, fgBlackGC, x+7, fHeight/2+8, x+7, fHeight/2+10);
         if ((fType & kSlider2) && (fType & kScaleBoth))
            gVirtualX->DrawLine(fId, fgBlackGC, x+7, fHeight/2-9, x+7, fHeight/2-11);
      }
   }
   if (fPos < fVmin) fPos = fVmin;
   if (fPos > fVmax) fPos = fVmax;

   // calc slider-picture position
   fRelPos = (((int)fWidth-16) * (fPos - fVmin)) / (fVmax - fVmin) + 8;
   if (fSliderPic) fSliderPic->Draw(fId, fgBckgndGC, fRelPos-6, fHeight/2-7);
}

//______________________________________________________________________________
 Bool_t TGHSlider::HandleButton(Event_t *event)
{
   // Handle mouse button event in horizontal slider widget.

   if (event->fType == kButtonPress) {
      if (event->fX >= fRelPos - 7 && event->fX <= fRelPos + 7) {
         // slider selected
         fDragging = kTRUE;
         fXp = event->fX - (fRelPos-7);
      } else {
         if (event->fCode == kButton1) {
            int m = (fVmax - fVmin) / (fWidth-16);
            if (event->fX < fRelPos) {
               fPos -= ((m) ? m : 1);
            }
            if (event->fX > fRelPos) {
               fPos += ((m) ? m : 1);
            }
         } else if (event->fCode == kButton2) {
            fPos = ((fVmax - fVmin) * event->fX) / (fWidth-16) + fVmin;
         }
         SendMessage(fMsgWindow, MK_MSG(kC_HSLIDER, kSL_POS),
                     fWidgetId, fPos);
         fClient->ProcessLine(fCommand, MK_MSG(kC_HSLIDER, kSL_POS),
                              fWidgetId, fPos);
      }
      fClient->NeedRedraw(this);

      // last argument kFALSE forces all specified events to this window
      gVirtualX->GrabPointer(fId, kButtonPressMask | kButtonReleaseMask |
                             kPointerMotionMask, kNone, kNone,
                             kTRUE, kFALSE);
   } else {
      // ButtonRelease
      fDragging = kFALSE;
      gVirtualX->GrabPointer(0, 0, 0, 0, kFALSE);  // ungrab pointer
   }
   return kTRUE;
}

//______________________________________________________________________________
 Bool_t TGHSlider::HandleMotion(Event_t *event)
{
   // Handle mouse motion event in horizontal slide widget.

   if (fDragging) {
      int old = fPos;
      fPos = ((fVmax - fVmin) * (event->fX - fXp)) / ((int)fWidth-16) + fVmin;
      if (fPos > fVmax) fPos = fVmax;
      if (fPos < fVmin) fPos = fVmin;

      // check if position changed
      if (old != fPos) {
         fClient->NeedRedraw(this);
         SendMessage(fMsgWindow, MK_MSG(kC_HSLIDER, kSL_POS),
                     fWidgetId, fPos);
         fClient->ProcessLine(fCommand, MK_MSG(kC_HSLIDER, kSL_POS),
                              fWidgetId, fPos);
      }
   }
   return kTRUE;
}