// @(#)root/histpainter:$Id$
// Author: Rene Brun   15/11/2002

/*************************************************************************
 * 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.             *
 *************************************************************************/

#include "Riostream.h"
#include "TROOT.h"
#include "TPaletteAxis.h"
#include "TVirtualPad.h"
#include "TStyle.h"
#include "TMath.h"
#include "TView.h"
#include "TH1.h"
#include "TGaxis.h"

ClassImp(TPaletteAxis)


//______________________________________________________________________________
/* Begin_Html
<center><h2>The palette painting class</h2></center>

A <tt>TPaletteAxis</tt> object is used to display the color palette when
drawing 2-d histograms.
<p>
The <tt>TPaletteAxis</tt> is automatically created drawn when drawing a 2-D
histogram when the option "Z" is specified.
<p>
A <tt>TPaletteAxis</tt> object is added to the histogram list of functions and
can be retrieved doing:
<pre>
   TPaletteAxis *palette = (TPaletteAxis*)h->GetListOfFunctions()->FindObject("palette");
</pre>
then the pointer <tt>palette</tt> can be used to change the pallette attributes.
<p>
Because the palette is created at painting time only, one must issue a:
<pre>
   gPad->Update();
</pre>
before retrieving the palette pointer in order to create the palette. The following
macro gives an example.

End_Html
Begin_Macro(source)
{
   TCanvas *c1 = new TCanvas("c1","c1",600,400);
   TH2F *h2 = new TH2F("h2","Example of a resized palette ",40,-4,4,40,-20,20);
   Float_t px, py;
   for (Int_t i = 0; i < 25000; i++) {
      gRandom->Rannor(px,py);
      h2->Fill(px,5*py);
   }
   gStyle->SetPalette(1);
   h2->Draw("COLZ");
   gPad->Update();
   TPaletteAxis *palette = (TPaletteAxis*)h2->GetListOfFunctions()->FindObject("palette");
   palette->SetY2NDC(0.7);
   return c1;
}
End_Macro
Begin_Html

<tt>TPaletteAxis</tt> inherits from <tt>TBox</tt> and <tt>TPave</tt>. The methods
allowing to specify the palette position are inherited from these two classes.
<p>
The palette can be interactively moved and resized. The context menu
can be used to set the axis attributes.
<p>
It is possible to select a range on the axis to set the min/max in z

End_Html */


//______________________________________________________________________________
TPaletteAxis::TPaletteAxis(): TPave()
{
   // Palette default constructor.

   fH  = 0;
   SetName("");
}


//______________________________________________________________________________
TPaletteAxis::TPaletteAxis(Double_t x1, Double_t y1, Double_t x2, Double_t  y2, TH1 *h)
   : TPave(x1, y1, x2, y2)
{
   // Palette normal constructor.

   fH = h;
   SetName("palette");
   TAxis *zaxis = fH->GetZaxis();
   fAxis.ImportAxisAttributes(zaxis);
   if (gPad->GetView()) SetBit(kHasView);
}


//______________________________________________________________________________
TPaletteAxis::~TPaletteAxis()
{
   // Palette destructor.

   if (fH) fH->GetListOfFunctions()->Remove(this);
}


//______________________________________________________________________________
TPaletteAxis::TPaletteAxis(const TPaletteAxis &palette) : TPave(palette)
{
   // Palette copy constructor.

   ((TPaletteAxis&)palette).Copy(*this);
}


//______________________________________________________________________________
TPaletteAxis& TPaletteAxis::operator=(const TPaletteAxis &orig)
{
   // Assignment operator.
   
   orig.Copy( *this );
   return *this;
}


//______________________________________________________________________________
void TPaletteAxis::Copy(TObject &obj) const
{
   // Copy a palette to a palette.

   TPave::Copy(obj);
   ((TPaletteAxis&)obj).fH    = fH;
   ((TPaletteAxis&)obj).fName = fName;
}


//______________________________________________________________________________
Int_t TPaletteAxis::DistancetoPrimitive(Int_t px, Int_t py)
{
   // Check if mouse on the axis region.

   Int_t plxmax = gPad->XtoAbsPixel(fX2);
   Int_t plymin = gPad->YtoAbsPixel(fY1);
   Int_t plymax = gPad->YtoAbsPixel(fY2);
   if (px > plxmax && px < plxmax + 30 && py >= plymax && py <= plymin) return px - plxmax;

   //otherwise check if inside the box
   return TPave::DistancetoPrimitive(px, py);
}


//______________________________________________________________________________
void TPaletteAxis::ExecuteEvent(Int_t event, Int_t px, Int_t py)
{
   // Check if mouse on the axis region.

   static Int_t kmode = 0;
   Int_t plxmin = gPad->XtoAbsPixel(fX1);
   Int_t plxmax = gPad->XtoAbsPixel(fX2);
   if (kmode != 0 || px <= plxmax) {
      if (event == kButton1Down) kmode = 1;
      TBox::ExecuteEvent(event, px, py);
      if (event == kButton1Up) kmode = 0;
      // In case palette coordinates have been modified, recompute NDC coordinates
      Double_t dpx  = gPad->GetX2() - gPad->GetX1();
      Double_t dpy  = gPad->GetY2() - gPad->GetY1();
      Double_t xp1  = gPad->GetX1();
      Double_t yp1  = gPad->GetY1();
      fX1NDC = (fX1 - xp1) / dpx;
      fY1NDC = (fY1 - yp1) / dpy;
      fX2NDC = (fX2 - xp1) / dpx;
      fY2NDC = (fY2 - yp1) / dpy;
      return;
   }
   gPad->SetCursor(kHand);
   static Double_t ratio1, ratio2;
   static Int_t px1old, py1old, px2old, py2old;
   Double_t temp, xmin, xmax;

   switch (event) {

      case kButton1Down:
         ratio1 = (gPad->AbsPixeltoY(py) - fY1) / (fY2 - fY1);
         py1old = gPad->YtoAbsPixel(fY1 + ratio1 * (fY2 - fY1));
         px1old = plxmin;
         px2old = plxmax;
         py2old = py1old;
         gVirtualX->DrawBox(px1old, py1old, px2old, py2old, TVirtualX::kHollow);
         gVirtualX->SetLineColor(-1);
         // No break !!!

      case kButton1Motion:
         gVirtualX->DrawBox(px1old, py1old, px2old, py2old, TVirtualX::kHollow);
         ratio2 = (gPad->AbsPixeltoY(py) - fY1) / (fY2 - fY1);
         py2old = gPad->YtoAbsPixel(fY1 + ratio2 * (fY2 - fY1));
         gVirtualX->DrawBox(px1old, py1old, px2old, py2old, TVirtualX::kHollow);
         break;

      case kButton1Up:
         if (gROOT->IsEscaped()) {
            gROOT->SetEscape(kFALSE);
            break;
         }

         ratio2 = (gPad->AbsPixeltoY(py) - fY1) / (fY2 - fY1);
         xmin = ratio1;
         xmax = ratio2;
         if (xmin > xmax) {
            temp   = xmin;
            xmin   = xmax;
            xmax   = temp;
            temp   = ratio1;
            ratio1 = ratio2;
            ratio2 = temp;
         }
         if (ratio2 - ratio1 > 0.05) {
            if (fH->GetDimension() == 2) {
               Double_t zmin = fH->GetMinimum();
               Double_t zmax = fH->GetMaximum();
               if (gPad->GetLogz()) {
                  if (zmin <= 0 && zmax > 0) zmin = TMath::Min((Double_t)1,
                                                                  (Double_t)0.001 * zmax);
                  zmin = TMath::Log10(zmin);
                  zmax = TMath::Log10(zmax);
               }
               Double_t newmin = zmin + (zmax - zmin) * ratio1;
               Double_t newmax = zmin + (zmax - zmin) * ratio2;
               if (newmin < zmin)newmin = fH->GetBinContent(fH->GetMinimumBin());
               if (newmax > zmax)newmax = fH->GetBinContent(fH->GetMaximumBin());
               if (gPad->GetLogz()) {
                  newmin = TMath::Exp(2.302585092994 * newmin);
                  newmax = TMath::Exp(2.302585092994 * newmax);
               }
               fH->SetMinimum(newmin);
               fH->SetMaximum(newmax);
               fH->SetBit(TH1::kIsZoomed);
            }
            gPad->Modified(kTRUE);
         }
         gVirtualX->SetLineColor(-1);
         kmode = 0;
         break;
   }
}


//______________________________________________________________________________
Int_t TPaletteAxis::GetBinColor(Int_t i, Int_t j)
{
   // Returns the color index of the bin (i,j).
   //
   // This function should be used after an histogram has been plotted with the
   // option COL or COLZ like in the following example:
   //
   //   h2->Draw("COLZ");
   //   gPad->Update();
   //   TPaletteAxis *palette =
   //      (TPaletteAxis*)h2->GetListOfFunctions()->FindObject("palette");
   //   Int_t ci = palette->GetBinColor(20,15);
   //
   // Then it is possible to retrieve the RGB components in the following way:
   //
   //   TColor *c = gROOT->GetColor(ci);
   //   float x,y,z;
   //   c->GetRGB(x,y,z);

   Double_t zc = fH->GetBinContent(i, j);
   return GetValueColor(zc);
}


//______________________________________________________________________________
char *TPaletteAxis::GetObjectInfo(Int_t /* px */, Int_t py) const
{
   // Displays the z value corresponding to cursor position py.

   Double_t z;
   static char info[64];

   Double_t zmin = fH->GetMinimum();
   Double_t zmax = fH->GetMaximum();
   Int_t   y1   = gPad->GetWh() - gPad->VtoPixel(fY1NDC);
   Int_t   y2   = gPad->GetWh() - gPad->VtoPixel(fY2NDC);
   Int_t   y    = gPad->GetWh() - py;

   if (gPad->GetLogz()) {
      if (zmin <= 0 && zmax > 0) zmin = TMath::Min((Double_t)1,
                                                      (Double_t)0.001 * zmax);
      Double_t zminl = TMath::Log10(zmin);
      Double_t zmaxl = TMath::Log10(zmax);
      Double_t zl    = (zmaxl - zminl) * ((Double_t)(y - y1) / (Double_t)(y2 - y1)) + zminl;
      z = TMath::Power(10., zl);
   } else {
      z = (zmax - zmin) * ((Double_t)(y - y1) / (Double_t)(y2 - y1)) + zmin;
   }

   snprintf(info, 64, "(z=%g)", z);
   return info;
}


//______________________________________________________________________________
Int_t TPaletteAxis::GetValueColor(Double_t zc)
{
   // Returns the color index of the given z value
   //
   // This function should be used after an histogram has been plotted with the
   // option COL or COLZ like in the following example:
   //
   //   h2->Draw("COLZ");
   //   gPad->Update();
   //   TPaletteAxis *palette =
   //      (TPaletteAxis*)h2->GetListOfFunctions()->FindObject("palette");
   //   Int_t ci = palette->GetValueColor(30.);
   //
   // Then it is possible to retrieve the RGB components in the following way:
   //
   //   TColor *c = gROOT->GetColor(ci);
   //   float x,y,z;
   //   c->GetRGB(x,y,z);

   Double_t wmin  = fH->GetMinimum();
   Double_t wmax  = fH->GetMaximum();
   Double_t wlmin = wmin;
   Double_t wlmax = wmax;

   if (gPad->GetLogz()) {
      if (wmin <= 0 && wmax > 0) wmin = TMath::Min((Double_t)1,
                                                      (Double_t)0.001 * wmax);
      wlmin = TMath::Log10(wmin);
      wlmax = TMath::Log10(wmax);
   }

   Int_t ncolors = gStyle->GetNumberOfColors();
   Int_t ndivz = fH->GetContour();
   if (ndivz == 0) return 0;
   ndivz = TMath::Abs(ndivz);
   Int_t theColor, color;
   Double_t scale = ndivz / (wlmax - wlmin);

   if (fH->TestBit(TH1::kUserContour) && gPad->GetLogz()) zc = TMath::Log10(zc);
   if (zc < wlmin) zc = wlmin;

   color = Int_t(0.01 + (zc - wlmin) * scale);

   theColor = Int_t((color + 0.99) * Double_t(ncolors) / Double_t(ndivz));
   return gStyle->GetColorPalette(theColor);
}


//______________________________________________________________________________
void TPaletteAxis::Paint(Option_t *)
{
   // Paint the palette.

   ConvertNDCtoPad();

   SetFillStyle(1001);
   Double_t ymin = fY1;
   Double_t ymax = fY2;
   Double_t xmin = fX1;
   Double_t xmax = fX2;
   Double_t wmin = fH->GetMinimum();
   Double_t wmax = fH->GetMaximum();
   Double_t wlmin = wmin;
   Double_t wlmax = wmax;
   Double_t y1, y2, w1, w2, zc;

   if ((wlmax - wlmin) <= 0) {
      Double_t mz = wlmin * 0.1;
      if (mz == 0) mz = 0.1;
      wlmin = wlmin - mz;
      wlmax = wlmax + mz;
      wmin  = wlmin;
      wmax  = wlmax;
   }

   if (gPad->GetLogz()) {
      if (wmin <= 0 && wmax > 0) wmin = TMath::Min((Double_t)1,
                                                      (Double_t)0.001 * wmax);
      wlmin = TMath::Log10(wmin);
      wlmax = TMath::Log10(wmax);
   }
   Double_t ws    = wlmax - wlmin;
   Int_t ncolors = gStyle->GetNumberOfColors();
   Int_t ndivz = fH->GetContour();
   if (ndivz == 0) return;
   ndivz = TMath::Abs(ndivz);
   Int_t theColor, color;
   Double_t scale = ndivz / (wlmax - wlmin);
   for (Int_t i = 0; i < ndivz; i++) {

      zc = fH->GetContourLevel(i);
      if (fH->TestBit(TH1::kUserContour) && gPad->GetLogz())
         zc = TMath::Log10(zc);
      w1 = zc;
      if (w1 < wlmin) w1 = wlmin;

      w2 = wlmax;
      if (i < ndivz - 1) {
         zc = fH->GetContourLevel(i + 1);
         if (fH->TestBit(TH1::kUserContour) && gPad->GetLogz())
            zc = TMath::Log10(zc);
         w2 = zc;
      }

      if (w2 <= wlmin) continue;
      y1 = ymin + (w1 - wlmin) * (ymax - ymin) / ws;
      y2 = ymin + (w2 - wlmin) * (ymax - ymin) / ws;

      if (fH->TestBit(TH1::kUserContour)) {
         color = i;
      } else {
         color = Int_t(0.01 + (w1 - wlmin) * scale);
      }

      theColor = Int_t((color + 0.99) * Double_t(ncolors) / Double_t(ndivz));
      SetFillColor(gStyle->GetColorPalette(theColor));
      TAttFill::Modify();
      gPad->PaintBox(xmin, y1, xmax, y2);
   }
   Int_t ndiv  = fH->GetZaxis()->GetNdivisions() % 100; //take primary divisions only
   char chopt[6] = "S   ";
   chopt[1] = 0;
   strncat(chopt, "+L", 2);
   if (ndiv < 0) {
      ndiv = TMath::Abs(ndiv);
      strncat(chopt, "N", 1);
   }
   if (gPad->GetLogz()) {
      wmin = TMath::Power(10., wlmin);
      wmax = TMath::Power(10., wlmax);
      strncat(chopt, "G", 1);
   }
   fAxis.PaintAxis(xmax, ymin, xmax, ymax, wmin, wmax, ndiv, chopt);
}


//______________________________________________________________________________
void TPaletteAxis::SavePrimitive(ostream &out, Option_t * /*= ""*/)
{
   // Save primitive as a C++ statement(s) on output stream out.

   //char quote = '"';
   out << "   " << endl;
   if (gROOT->ClassSaved(TPaletteAxis::Class())) {
      out << "   ";
   } else {
      out << "   " << ClassName() << " *";
   }
   if (fOption.Contains("NDC")) {
      out << "palette = new " << ClassName() << "(" << fX1NDC << "," << fY1NDC << "," << fX2NDC << "," << fY2NDC
          << "," << fH->GetName() << ");" << endl;
   } else {
      out << "palette = new " << ClassName() << "(" << fX1 << "," << fY1 << "," << fX2 << "," << fY2
          << "," << fH->GetName() << ");" << endl;
   }
   out << "palette->SetLabelColor(" << fAxis.GetLabelColor() << ");" << endl;
   out << "palette->SetLabelFont("  << fAxis.GetLabelFont() << ");" << endl;
   out << "palette->SetLabelOffset(" << fAxis.GetLabelOffset() << ");" << endl;
   out << "palette->SetLabelSize("  << fAxis.GetLabelSize() << ");" << endl;
   out << "palette->SetTitleOffset(" << fAxis.GetTitleOffset() << ");" << endl;
   out << "palette->SetTitleSize("  << fAxis.GetTitleSize() << ");" << endl;
   SaveFillAttributes(out, "palette", -1, -1);
   SaveLineAttributes(out, "palette", 1, 1, 1);
}


//______________________________________________________________________________
void TPaletteAxis::UnZoom()
{
   // Unzoom the palette

   TView *view = gPad->GetView();
   if (view) {
      delete view;
      gPad->SetView(0);
   }
   fH->GetZaxis()->SetRange(0, 0);
   if (fH->GetDimension() == 2) {
      fH->SetMinimum();
      fH->SetMaximum();
      fH->ResetBit(TH1::kIsZoomed);
   }
}