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

   Audacity: A Digital Audio Editor

   EffectEqualization.cpp

   Mitch Golden
   Vaughan Johnson (Preview)
   Martyn Shaw (FIR filters, response curve, graphic EQ)

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

   \file Equalization.cpp
   \brief Implements EffectEqualiztaion, EqualizationDialog,
   EqualizationPanel, EQCurve and EQPoint.

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


   \class EffectEqualization
   \brief An Effect that modifies volume in different frequency bands.

   Performs filtering, using an FFT to do a FIR filter.
   It lets the user draw an arbitrary envelope (using the same
   envelope editing code that is used to edit the track's
   amplitude envelope).

   Also allows the curve to be specified with a series of 'graphic EQ'
   sliders.

   The filter is applied using overlap/add of Hann windows.

   Clone of the FFT Filter effect, no longer part of Audacity.

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

   \class EqualizationPanel
   \brief EqualizationPanel is used with EqualizationDialog and controls
   a graph for EffectEqualization.  We should look at amalgamating the
   various graphing code, such as provided by FrequencyPlotDialog and FilterPanel.

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

   \class EQCurve
   \brief EQCurve is used with EffectEqualization.

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

   \class EQPoint
   \brief EQPoint is used with EQCurve and hence EffectEqualization.

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



#include "Equalization.h"
#include "LoadEffects.h"

#include <math.h>
#include <vector>

#include <wx/setup.h> // for wxUSE_* macros

#include <wx/bitmap.h>
#include <wx/button.h>
#include <wx/brush.h>
#include <wx/button.h>  // not really needed here
#include <wx/dcclient.h>
#include <wx/dcmemory.h>
#include <wx/event.h>
#include <wx/listctrl.h>
#include <wx/log.h>
#include <wx/image.h>
#include <wx/intl.h>
#include <wx/choice.h>
#include <wx/radiobut.h>
#include <wx/slider.h>
#include <wx/stattext.h>
#include <wx/string.h>
#include <wx/textdlg.h>
#include <wx/ffile.h>
#include <wx/filefn.h>
#include <wx/stdpaths.h>
#include <wx/settings.h>
#include <wx/sizer.h>
#include <wx/checkbox.h>
#include <wx/tooltip.h>
#include <wx/utils.h>

#include "AColor.h"
#include "ConfigInterface.h"
#include "../ShuttleAutomation.h"
#include "../ShuttleGui.h"
#include "PlatformCompatibility.h"
#include "FileNames.h"
#include "Envelope.h"
#include "../EnvelopeEditor.h"
#include "FFT.h"
#include "Prefs.h"
#include "Project.h"
#include "Theme.h"
#include "../TrackArtist.h"
#include "../WaveClip.h"
#include "ViewInfo.h"
#include "../WaveTrack.h"
#include "../widgets/Ruler.h"
#include "../widgets/AudacityTextEntryDialog.h"
#include "XMLFileReader.h"
#include "AllThemeResources.h"
#include "float_cast.h"

#if wxUSE_ACCESSIBILITY
#include "../widgets/WindowAccessible.h"
#endif

#include "../widgets/FileDialog/FileDialog.h"

#ifdef EXPERIMENTAL_EQ_SSE_THREADED
#include "Equalization48x.h"
#endif


enum
{
   ID_Length = 10000,
   ID_dBMax,
   ID_dBMin,
   ID_Clear,
   ID_Invert,
   ID_Mode,
   ID_Draw,
   ID_Graphic,
   ID_Interp,
   ID_Linear,
   ID_Grid,
   ID_Curve,
   ID_Manage,
   ID_Delete,
#ifdef EXPERIMENTAL_EQ_SSE_THREADED
   ID_DefaultMath,
   ID_SSE,
   ID_SSEThreaded,
   ID_AVX,
   ID_AVXThreaded,
   ID_Bench,
#endif
   ID_Slider,   // needs to come last
};

// Increment whenever EQCurves.xml is updated
#define EQCURVES_VERSION   1
#define EQCURVES_REVISION  0
#define UPDATE_ALL 0 // 0 = merge NEW presets only, 1 = Update all factory presets.

const EnumValueSymbol EffectEqualization::kInterpStrings[nInterpolations] =
{
   // These are acceptable dual purpose internal/visible names

   /* i18n-hint: Technical term for a kind of curve.*/
   { XO("B-spline") },
   { XO("Cosine") },
   { XO("Cubic") }
};

static const double kThirdOct[] =
{
   20., 25., 31., 40., 50., 63., 80., 100., 125., 160., 200.,
   250., 315., 400., 500., 630., 800., 1000., 1250., 1600., 2000.,
   2500., 3150., 4000., 5000., 6300., 8000., 10000., 12500., 16000., 20000.,
};

const EffectParameterMethods& EffectEqualization::Parameters() const
{
   static CapturedParameters<EffectEqualization,
      FilterLength,
      // CurveName,
      InterpLin,
      // Pretty sure the interpolation name shouldn't have been interpreted when
      // specified in chains, but must keep it that way for compatibility.
      InterpMeth
   > parameters {
      [](EffectEqualization &, EffectSettings &, EffectEqualization &effect,
         bool updating){
         if (updating) {
            if (effect.mInterp >= nInterpolations)
               effect.mInterp -= nInterpolations;
            effect.mEnvelope =
               (effect.mLin ? effect.mLinEnvelope : effect.mLogEnvelope).get();
         }
         return true;
      }
   };
   return parameters;
}

///----------------------------------------------------------------------------
// EffectEqualization
//----------------------------------------------------------------------------

const ComponentInterfaceSymbol EffectEqualization::Symbol
{ XO("Equalization") };

// namespace{ BuiltinEffectsModule::Registration< EffectEqualization > reg; }

// "Filter Curve EQ" in the user-facing string, but preserve the old
// internal string
const ComponentInterfaceSymbol EffectEqualizationCurve::Symbol
{ wxT("Filter Curve"), XO("Filter Curve EQ") };

namespace{ BuiltinEffectsModule::Registration< EffectEqualizationCurve > reg2; }

const ComponentInterfaceSymbol EffectEqualizationGraphic::Symbol
{ wxT("Graphic EQ"), XO("Graphic EQ") };

namespace{ BuiltinEffectsModule::Registration< EffectEqualizationGraphic > reg3; }

BEGIN_EVENT_TABLE(EffectEqualization, wxEvtHandler)
   EVT_SIZE( EffectEqualization::OnSize )

   EVT_SLIDER( ID_Length, EffectEqualization::OnSliderM )
   EVT_SLIDER( ID_dBMax, EffectEqualization::OnSliderDBMAX )
   EVT_SLIDER( ID_dBMin, EffectEqualization::OnSliderDBMIN )
   EVT_COMMAND_RANGE(ID_Slider,
                     ID_Slider + NUMBER_OF_BANDS - 1,
                     wxEVT_COMMAND_SLIDER_UPDATED,
                     EffectEqualization::OnSlider)
   EVT_CHOICE( ID_Interp, EffectEqualization::OnInterp )

   EVT_CHOICE( ID_Curve, EffectEqualization::OnCurve )
   EVT_BUTTON( ID_Manage, EffectEqualization::OnManage )
   EVT_BUTTON( ID_Clear, EffectEqualization::OnClear )
   EVT_BUTTON( ID_Invert, EffectEqualization::OnInvert )

   EVT_RADIOBUTTON(ID_Draw, EffectEqualization::OnDrawMode)
   EVT_RADIOBUTTON(ID_Graphic, EffectEqualization::OnGraphicMode)
   EVT_CHECKBOX(ID_Linear, EffectEqualization::OnLinFreq)
   EVT_CHECKBOX(ID_Grid, EffectEqualization::OnGridOnOff)

#ifdef EXPERIMENTAL_EQ_SSE_THREADED
   EVT_RADIOBUTTON(ID_DefaultMath, EffectEqualization::OnProcessingRadio)
   EVT_RADIOBUTTON(ID_SSE, EffectEqualization::OnProcessingRadio)
   EVT_RADIOBUTTON(ID_SSEThreaded, EffectEqualization::OnProcessingRadio)
   EVT_RADIOBUTTON(ID_AVX, EffectEqualization::OnProcessingRadio)
   EVT_RADIOBUTTON(ID_AVXThreaded, EffectEqualization::OnProcessingRadio)
   EVT_BUTTON(ID_Bench, EffectEqualization::OnBench)
#endif
END_EVENT_TABLE()

EffectEqualization::EffectEqualization(int Options)
   : mFFTBuffer{ windowSize }
   , mFilterFuncR{ windowSize }
   , mFilterFuncI{ windowSize }
{
   Parameters().Reset(*this);

   mOptions = Options;
   mGraphic = NULL;
   mDraw = NULL;
   mCurve = NULL;
   mPanel = NULL;
   mMSlider = NULL;

   hFFT = GetFFT(windowSize);

   SetLinearEffectFlag(true);

   mCurveName = CurveName.def;

   GetConfig(GetDefinition(), PluginSettings::Private,
      CurrentSettingsGroup(), wxT("dBMin"), mdBMin, dBMin.def);
   GetConfig(GetDefinition(), PluginSettings::Private,
      CurrentSettingsGroup(), wxT("dBMax"), mdBMax, dBMax.def);
   GetConfig(GetDefinition(), PluginSettings::Private,
      CurrentSettingsGroup(), wxT("DrawMode"), mDrawMode, DrawMode.def);
   GetConfig(GetDefinition(), PluginSettings::Private,
      CurrentSettingsGroup(), wxT("DrawGrid"), mDrawGrid, DrawGrid.def);

   mLogEnvelope = std::make_unique<Envelope>
      (false,
       dBMin.min, dBMax.max, // MB: this is the highest possible range
       0.0);
   mLogEnvelope->SetTrackLen(1.0);

   mLinEnvelope = std::make_unique<Envelope>
      (false,
       dBMin.min, dBMax.max, // MB: this is the highest possible range
       0.0);
   mLinEnvelope->SetTrackLen(1.0);

   mEnvelope = (mLin ? mLinEnvelope : mLogEnvelope).get();

   mWindowSize = windowSize;

   mDirty = false;
   mDisallowCustom = false;

   // Load the EQ curves
   LoadCurves();

   // Note: initial curve is set in TransferDataToWindow

   mBandsInUse = NUMBER_OF_BANDS;
   //double loLog = log10(mLoFreq);
   //double stepLog = (log10(mHiFreq) - loLog)/((double)NUM_PTS-1.);
   for(int i=0; i<NUM_PTS-1; i++)
      mWhens[i] = (double)i/(NUM_PTS-1.);
   mWhens[NUM_PTS-1] = 1.;
   mWhenSliders[NUMBER_OF_BANDS] = 1.;
   mEQVals[NUMBER_OF_BANDS] = 0.;

#ifdef EXPERIMENTAL_EQ_SSE_THREADED
   bool useSSE;
   GetPrivateConfig(CurrentSettingsGroup(), wxT("/SSE/GUI"), useSSE, false);
   if(useSSE && !mEffectEqualization48x)
      mEffectEqualization48x = std::make_unique<EffectEqualization48x>();
   else if(!useSSE)
      mEffectEqualization48x.reset();
   mBench=false;
#endif

   // We expect these Hi and Lo frequencies to be overridden by Init().
   // Don't use inputTracks().  See bug 2321.
#if 0
   auto trackList = inputTracks();
   const auto t = trackList
      ? *trackList->Any< const WaveTrack >().first
      : nullptr
   ;
   mHiFreq =
      (t
         ? t->GetRate()
         : mProjectRate)
      / 2.0;
#endif
   mHiFreq = mProjectRate / 2.0;
   mLoFreq = loFreqI;
}


EffectEqualization::~EffectEqualization()
{
}

// ComponentInterface implementation

ComponentInterfaceSymbol EffectEqualization::GetSymbol() const
{
   if( mOptions == kEqOptionGraphic )
      return EffectEqualizationGraphic::Symbol;
   if( mOptions == kEqOptionCurve )
      return EffectEqualizationCurve::Symbol;
   return EffectEqualization::Symbol;
}

TranslatableString EffectEqualization::GetDescription() const
{
   return XO("Adjusts the volume levels of particular frequencies");
}

ManualPageID EffectEqualization::ManualPage() const
{
   // Bug 2509: Must use _ and not space in names.
   if( mOptions == kEqOptionGraphic )
      return L"Graphic_EQ";
   if( mOptions == kEqOptionCurve )
      return L"Filter_Curve_EQ";
   return L"Equalization";
}

// EffectDefinitionInterface implementation

EffectType EffectEqualization::GetType() const
{
   return EffectTypeProcess;
}

bool EffectEqualization::VisitSettings(
   ConstSettingsVisitor &visitor, const EffectSettings &settings) const
{
   Effect::VisitSettings(visitor, settings);

   // Curve point parameters -- how many isn't known statically
   if( dynamic_cast<ShuttleGetAutomation*>(&visitor)) {
      int numPoints = mCurves[ 0 ].points.size();
      int point;
      for( point = 0; point < numPoints; point++ )
      {
         const wxString nameFreq = wxString::Format("f%i",point);
         const wxString nameVal = wxString::Format("v%i",point);
         visitor.Define( mCurves[ 0 ].points[ point ].Freq, nameFreq,
            0.0, 0.0, 0.0, 0.0 );
         visitor.Define( mCurves[ 0 ].points[ point ].dB, nameVal,
            0.0, 0.0, 0.0, 0.0 );
      }
   }
   return true;
}

bool EffectEqualization::VisitSettings(
   SettingsVisitor &visitor, EffectSettings &settings)
{
   Effect::VisitSettings(visitor, settings);

   // Curve point parameters -- how many isn't known statically
   {
      mCurves[0].points.clear();
   
      for (int i = 0; i < 200; i++)
      {
         const wxString nameFreq = wxString::Format("f%i",i);
         const wxString nameVal = wxString::Format("v%i",i);
         double f = -1000.0;
         double d = 0.0;
         visitor.Define( f, nameFreq, 0.0,  -10000.0, 1000000.0, 0.0 );
         visitor.Define( d, nameVal,  0.0, -10000.0, 10000.0, 0.0 );
         if( f <= 0.0 )
            break;
         mCurves[0].points.push_back( EQPoint( f,d ));
      }
      setCurve( 0 );
   }
   return true;
}

OptionalMessage
EffectEqualization::LoadFactoryDefaults(EffectSettings &settings) const
{
   // To do: externalize state so const_cast isn't needed
   if (!const_cast<EffectEqualization&>(*this).DoLoadFactoryDefaults(settings))
      return {};
   return { nullptr };
}

OptionalMessage
EffectEqualization::DoLoadFactoryDefaults(EffectSettings &settings)
{
   mdBMin = dBMin.def;
   mdBMax = dBMax.def;
   mDrawMode = DrawMode.def;
   mDrawGrid = DrawGrid.def;

   if( mOptions == kEqOptionCurve)
      mDrawMode = true;
   if( mOptions == kEqOptionGraphic)
      mDrawMode = false;

   return Effect::LoadFactoryDefaults(settings);
}

// Constants determining who the prests are for.
const bool kCURVE = false;
const bool kBOTH = true;

static const struct
{
   const bool bForBoth; // more extended set is used for Filter EQ
   // See Bug 2254 for rationale.
   const TranslatableString name;
   const wxChar *values;
}
FactoryPresets[] =
{
   { kCURVE, XO("100Hz Rumble"),           wxT("f0=\"20.0\" v0=\"-80.0\" f1=\"49.237316986327\" v1=\"-33.107692718506\" f2=\"54.196034330446\" v2=\"-29.553844451904\" f3=\"88.033573501041\" v3=\"-6.923076629639\" f4=\"95.871851182279\" v4=\"-4.523078918457\" f5=\"108.957037410504\" v5=\"-1.938461303711\" f6=\"123.828171198057\" v6=\"-0.73846244812\" f7=\"149.228077614658\" v7=\"-0.092308044434\"") },
   { kCURVE, XO("AM Radio"),               wxT("f0=\"20.0\" v0=\"-63.67\" f1=\"31.0\" v1=\"-33.219\" f2=\"50.0\" v2=\"-3.01\" f3=\"63.0\" v3=\"-0.106\" f4=\"100.0\" v4=\"0.0\" f5=\"2500.0\" v5=\"0.0\" f6=\"4000.0\" v6=\"-0.614\" f7=\"5000.0\" v7=\"-8.059\" f8=\"8000.0\" v8=\"-39.981\" f9=\"20000.0\" v9=\"-103.651\" f10=\"48000.0\" v10=\"-164.485\"") },
   { kBOTH,  XO("Bass Boost"),             wxT("f0=\"100.0\" v0=\"9.0\" f1=\"500.0\" v1=\"0.0\"") },
   { kBOTH,  XO("Bass Cut"),               wxT("f0=\"150.0\" v0=\"-50.0\" f1=\"300.0\" v1=\"0.0\"") },
   { kCURVE, XO("Low rolloff for speech"), wxT("f0=\"50.0\" v0=\"-120.0\" f1=\"60.0\" v1=\"-50.0\" f2=\"65.0\" v2=\"-24.0\" f3=\"70.0\" v3=\"-12.0\" f4=\"80.0\" v4=\"-4.0\" f5=\"90.0\" v5=\"-1.0\" f6=\"100.0\" v6=\"0.0\"") },
   { kBOTH,  XO("RIAA"),                   wxT("f0=\"20.0\" v0=\"19.274\" f1=\"25.0\" v1=\"18.954\" f2=\"31.0\" v2=\"18.516\" f3=\"40.0\" v3=\"17.792\" f4=\"50.0\" v4=\"16.946\" f5=\"63.0\" v5=\"15.852\" f6=\"80.0\" v6=\"14.506\" f7=\"100.0\" v7=\"13.088\" f8=\"125.0\" v8=\"11.563\" f9=\"160.0\" v9=\"9.809\" f10=\"200.0\" v10=\"8.219\" f11=\"250.0\" v11=\"6.677\" f12=\"315.0\" v12=\"5.179\" f13=\"400.0\" v13=\"3.784\" f14=\"500.0\" v14=\"2.648\" f15=\"630.0\" v15=\"1.642\" f16=\"800.0\" v16=\"0.751\" f17=\"1000.0\" v17=\"0.0\" f18=\"1250.0\" v18=\"-0.744\" f19=\"1600.0\" v19=\"-1.643\" f20=\"2000.0\" v20=\"-2.589\" f21=\"2500.0\" v21=\"-3.7\" f22=\"3150.0\" v22=\"-5.038\" f23=\"4000.0\" v23=\"-6.605\" f24=\"5000.0\" v24=\"-8.21\" f25=\"6300.0\" v25=\"-9.98\" f26=\"8000.0\" v26=\"-11.894\" f27=\"10000.0\" v27=\"-13.734\" f28=\"12500.0\" v28=\"-15.609\" f29=\"16000.0\" v29=\"-17.708\" f30=\"20000.0\" v30=\"-19.62\" f31=\"25000.0\" v31=\"-21.542\" f32=\"48000.0\" v32=\"-27.187\"") },
   { kCURVE, XO("Telephone"),              wxT("f0=\"20.0\" v0=\"-94.087\" f1=\"200.0\" v1=\"-14.254\" f2=\"250.0\" v2=\"-7.243\" f3=\"315.0\" v3=\"-2.245\" f4=\"400.0\" v4=\"-0.414\" f5=\"500.0\" v5=\"0.0\" f6=\"2500.0\" v6=\"0.0\" f7=\"3150.0\" v7=\"-0.874\" f8=\"4000.0\" v8=\"-3.992\" f9=\"5000.0\" v9=\"-9.993\" f10=\"48000.0\" v10=\"-88.117\"") },
   { kBOTH,  XO("Treble Boost"),           wxT("f0=\"4000.0\" v0=\"0.0\" f1=\"5000.0\" v1=\"9.0\"") },
   { kBOTH,  XO("Treble Cut"),             wxT("f0=\"6000.0\" v0=\"0.0\" f1=\"10000.0\" v1=\"-110.0\"") },
   { kCURVE, XO("Walkie-talkie"),          wxT("f0=\"100.0\" v0=\"-120.0\" f1=\"101.0\" v1=\"0.0\" f2=\"2000.0\" v2=\"0.0\" f3=\"2001.0\" v3=\"-120.0\"") },
};




RegistryPaths EffectEqualization::GetFactoryPresets() const
{
   RegistryPaths names;

   for (size_t i = 0; i < WXSIZEOF(FactoryPresets); i++)
   {
      if ((mOptions == kEqOptionGraphic) && (FactoryPresets[i].bForBoth == false))
         continue;
      names.push_back(FactoryPresets[i].name.Translation());
   }

   return names;
}

OptionalMessage
EffectEqualization::LoadFactoryPreset(int id, EffectSettings &settings) const
{
   int index = -1;
   for (size_t i = 0; i < WXSIZEOF(FactoryPresets); i++)
   {
      if ((mOptions == kEqOptionGraphic) && (FactoryPresets[i].bForBoth == false))
         continue;
      if (id-- == 0) {
         index = i;
         break;
      }
   }
   if (index < 0)
      return {};

   // mParams = 
   wxString params = FactoryPresets[index].values;

   CommandParameters eap(params);
   ShuttleSetAutomation S;
   S.SetForWriting( &eap );
   // To do: externalize state so const_cast isn't needed
   if (!const_cast<EffectEqualization*>(this)->VisitSettings(S, settings))
      return {};
   return { nullptr };
}



// EffectUIClientInterface implementation

bool EffectEqualization::ValidateUI(EffectSettings &)
{
   // If editing a macro, we don't want to be using the unnamed curve so
   // we offer to save it.

   if (mDisallowCustom && mCurveName == wxT("unnamed"))
   {
      // PRL:  This is unreachable.  mDisallowCustom is always false.

      Effect::MessageBox(
         XO("To use this filter curve in a macro, please choose a new name for it.\nChoose the 'Save/Manage Curves...' button and rename the 'unnamed' curve, then use that one."),
         wxOK | wxCENTRE,
         XO("Filter Curve EQ needs a different name") );
      return false;
   }

   // Update unnamed curve (so it's there for next time)
   //(done in a hurry, may not be the neatest -MJS)
   if (mDirty && !mDrawMode)
   {
      size_t numPoints = mLogEnvelope->GetNumberOfPoints();
      Doubles when{ numPoints };
      Doubles value{ numPoints };
      mLogEnvelope->GetPoints(when.get(), value.get(), numPoints);
      for (size_t i = 0, j = 0; j + 2 < numPoints; i++, j++)
      {
         if ((value[i] < value[i + 1] + .05) && (value[i] > value[i + 1] - .05) &&
            (value[i + 1] < value[i + 2] + .05) && (value[i + 1] > value[i + 2] - .05))
         {   // within < 0.05 dB?
            mLogEnvelope->Delete(j + 1);
            numPoints--;
            j--;
         }
      }
      Select((int) mCurves.size() - 1);
   }
   SaveCurves();

   // TODO: just visit these effect settings the default way
   SetConfig(GetDefinition(), PluginSettings::Private,
      CurrentSettingsGroup(), wxT("dBMin"), mdBMin);
   SetConfig(GetDefinition(), PluginSettings::Private,
      CurrentSettingsGroup(), wxT("dBMax"), mdBMax);
   SetConfig(GetDefinition(), PluginSettings::Private,
      CurrentSettingsGroup(), wxT("DrawMode"), mDrawMode);
   SetConfig(GetDefinition(), PluginSettings::Private,
      CurrentSettingsGroup(), wxT("DrawGrid"), mDrawGrid);

   return true;
}

// Effect implementation

wxString EffectEqualization::GetPrefsPrefix()
{
   wxString base = wxT("/Effects/Equalization/");
   if( mOptions == kEqOptionGraphic )
      base = wxT("/Effects/GraphicEq/");
   else if( mOptions == kEqOptionCurve )
      base = wxT("/Effects/FilterCurve/");
   return base;
}

bool EffectEqualization::Init()
{
   int selcount = 0;
   double rate = 0.0;

   if (const auto project = FindProject()) {
      auto trackRange = TrackList::Get(*project).Selected<const WaveTrack>();
      if (trackRange) {
         rate = (*(trackRange.first++)) -> GetRate();
         ++selcount;

         for (auto track : trackRange) {
            if (track->GetRate() != rate) {
               Effect::MessageBox(
                  XO(
   "To apply Equalization, all selected tracks must have the same sample rate.") );
               return(false);
            }
            ++selcount;
         }
      }
   }
   else
      // Editing macro parameters, use this default
      rate = 44100.0;

   mHiFreq = rate / 2.0;
   // Unlikely, but better than crashing.
   if (mHiFreq <= loFreqI) {
      Effect::MessageBox(
         XO("Track sample rate is too low for this effect."),
         wxOK | wxCENTRE,
         XO("Effect Unavailable") );
      return(false);
   }

   mLoFreq = loFreqI;

   mBandsInUse = 0;
   while (kThirdOct[mBandsInUse] <= mHiFreq) {
      mBandsInUse++;
      if (mBandsInUse == NUMBER_OF_BANDS)
         break;
   }

   mEnvelope = (mLin ? mLinEnvelope : mLogEnvelope).get();

   setCurve(mCurveName);

   CalcFilter();

   return(true);
}

bool EffectEqualization::Process(EffectInstance &, EffectSettings &)
{
#ifdef EXPERIMENTAL_EQ_SSE_THREADED
   if(mEffectEqualization48x) {
      if(mBench) {
         mBench=false;
         return mEffectEqualization48x->Benchmark(this);
      }
      else
         return mEffectEqualization48x->Process(this);
   }
#endif
   this->CopyInputTracks(); // Set up mOutputTracks.
   CalcFilter();
   bool bGoodResult = true;

   int count = 0;
   for( auto track : mOutputTracks->Selected< WaveTrack >() ) {
      double trackStart = track->GetStartTime();
      double trackEnd = track->GetEndTime();
      double t0 = mT0 < trackStart? trackStart: mT0;
      double t1 = mT1 > trackEnd? trackEnd: mT1;

      if (t1 > t0) {
         auto start = track->TimeToLongSamples(t0);
         auto end = track->TimeToLongSamples(t1);
         auto len = end - start;

         if (!ProcessOne(count, track, start, len))
         {
            bGoodResult = false;
            break;
         }
      }

      count++;
   }

   this->ReplaceProcessedTracks(bGoodResult);
   return bGoodResult;
}

bool EffectEqualization::CloseUI()
{
   mCurve = NULL;
   mPanel = NULL;

   return Effect::CloseUI();
}

std::unique_ptr<EffectUIValidator> EffectEqualization::PopulateOrExchange(
   ShuttleGui & S, EffectInstance &, EffectSettingsAccess &access,
   const EffectOutputs *)
{
   S.SetBorder(0);

   S.SetSizerProportion(1);
   S.Prop(1).StartMultiColumn(1, wxEXPAND);
   {
      S.SetStretchyCol(0);
      //S.SetStretchyRow(0); // The 5px Top border
      S.SetStretchyRow(1);   // The Graph
      S.SetStretchyRow(2);   // The EQ sliders
      szrV = S.GetSizer();

      // -------------------------------------------------------------------
      // ROW 0: Top border
      // -------------------------------------------------------------------
      S.AddSpace(5);

      // -------------------------------------------------------------------
      // ROW 1: Equalization panel and sliders for vertical scale
      // -------------------------------------------------------------------
      S.SetSizerProportion(1);
      S.Prop(1).StartMultiColumn(3, wxEXPAND);
      {
         S.SetStretchyCol(1);
         S.SetStretchyRow(0);
         szr1 = S.GetSizer();

         S.StartVerticalLay(wxEXPAND, 1);
         {
            mdBRuler = safenew RulerPanel(
               S.GetParent(), wxID_ANY, wxVERTICAL,
               wxSize{ 100, 100 }, // Ruler can't handle small sizes
               RulerPanel::Range{ 60.0, -120.0 },
               Ruler::LinearDBFormat,
               XO("dB"),
               RulerPanel::Options{}
                  .LabelEdges(true)
                  .TicksAtExtremes(true)
                  .TickColour( { 0, 0, 0 } )
            );

            S.Prop(0).AddSpace(0, 1);
            S.Prop(1)
               .Position(wxEXPAND)
               .AddWindow(mdBRuler);
            S.AddSpace(0, 1);
         }
         S.EndVerticalLay();

         mPanel = safenew EqualizationPanel(S.GetParent(), wxID_ANY, this);
         S.Prop(1)
            .Position(wxEXPAND)
            .MinSize( { wxDefaultCoord, wxDefaultCoord } )
            .AddWindow(mPanel);

         S.SetBorder(5);
         S.StartVerticalLay();
         {
            S.AddVariableText(XO("+ dB"), false, wxCENTER);
            mdBMaxSlider = S.Id(ID_dBMax)
               .Name(XO("Max dB"))
               .Style(wxSL_VERTICAL | wxSL_INVERSE)
               .AddSlider( {}, 30, 60, 0);
#if wxUSE_ACCESSIBILITY
            mdBMaxSlider->SetAccessible(safenew SliderAx(mdBMaxSlider, XO("%d dB")));
#endif

            mdBMinSlider = S.Id(ID_dBMin)
               .Name(XO("Min dB"))
               .Style(wxSL_VERTICAL | wxSL_INVERSE)
               .AddSlider( {}, -30, -10, -120);
            S.AddVariableText(XO("- dB"), false, wxCENTER);
#if wxUSE_ACCESSIBILITY
            mdBMinSlider->SetAccessible(safenew SliderAx(mdBMinSlider, XO("%d dB")));
#endif
         }
         S.EndVerticalLay();
         S.SetBorder(0);

         // -------------------------------------------------------------------
         // Frequency ruler below graph
         // -------------------------------------------------------------------

         // Column 1 is empty
         S.AddSpace(1, 1);

         mFreqRuler  = safenew RulerPanel(
            S.GetParent(), wxID_ANY, wxHORIZONTAL,
            wxSize{ 100, 100 }, // Ruler can't handle small sizes
            RulerPanel::Range{ mLoFreq, mHiFreq },
            Ruler::IntFormat,
            XO("Hz"),
            RulerPanel::Options{}
               .Log(true)
               .Flip(true)
               .LabelEdges(true)
               .TicksAtExtremes(true)
               .TickColour( { 0, 0, 0 } )
         );

         S.SetBorder(1);
         S.Prop(1)
            .Position(wxEXPAND | wxALIGN_LEFT | wxALIGN_TOP | wxLEFT)
            .AddWindow(mFreqRuler);
         S.SetBorder(0);

         // Column 3 is empty
         S.AddSpace(1, 1);
      }
      S.EndMultiColumn();

      // -------------------------------------------------------------------
      // ROW 2: Graphic EQ
      // -------------------------------------------------------------------
      S.SetSizerProportion(1);
      S.StartHorizontalLay(wxEXPAND, 1);
      {
         szrG = S.GetSizer();

         // Panel used to host the sliders since they will be positioned manually.
         //mGraphicPanel = S.Prop(1)
            //.Position(wxEXPAND)
            //.Size( { -1, 150 } )
            //.StartPanel();
         wxWindow *pParent = S.GetParent();
         S.AddSpace(15,0);
         {

         // for (int i = 0; (i < NUMBER_OF_BANDS) && (kThirdOct[i] <= mHiFreq); ++i)
         // May show more sliders than needed.  Fixes Bug 2269
         for (int i = 0; i < NUMBER_OF_BANDS; ++i)
         {
            TranslatableString freq = kThirdOct[i] < 1000.
               ? XO("%d Hz").Format((int)kThirdOct[i])
               : XO("%g kHz").Format(kThirdOct[i] / 1000.);
            TranslatableString fNum = kThirdOct[i] < 1000.
               ? Verbatim("%d").Format((int)kThirdOct[i])
               /* i18n-hint k is SI abbreviation for x1,000.  Usually unchanged in translation. */
               : XO("%gk").Format(kThirdOct[i] / 1000.);
            S.StartVerticalLay();
            {
               S.AddFixedText( fNum  );
               mSliders[i] = safenew wxSliderWrapper(pParent, ID_Slider + i, 0, -20, +20,
                  wxDefaultPosition, wxSize(-1,50), wxSL_VERTICAL | wxSL_INVERSE);

#if wxUSE_ACCESSIBILITY
               mSliders[i]->SetAccessible(safenew SliderAx(mSliders[i], XO("%d dB")));
#endif

               mSlidersOld[i] = 0;
               mEQVals[i] = 0.;
               S.Prop(1)
                  .Name(freq)
                  .ConnectRoot(
                     wxEVT_ERASE_BACKGROUND, &EffectEqualization::OnErase)
                  .Position(wxEXPAND)
                  .Size({ -1, 50 })
                  .AddWindow(mSliders[i]);
            }
            S.EndVerticalLay();
         }
         S.AddSpace(15,0);

         } //S.EndPanel();
      }
      S.EndHorizontalLay();

      // -------------------------------------------------------------------
      // ROW 4: Various controls
      // -------------------------------------------------------------------
      S.SetSizerProportion(1);
      S.Prop(1).StartMultiColumn(7, wxALIGN_CENTER_HORIZONTAL);
      {
         S.SetBorder(5);

         S.AddSpace(5, 5);

         if( mOptions == kEqLegacy )
         {
            S.StartHorizontalLay(wxALIGN_RIGHT | wxALIGN_CENTER_VERTICAL);
            {
               S.AddPrompt(XXO("&EQ Type:"));
            }
            S.EndHorizontalLay();

            S.StartHorizontalLay(wxALIGN_LEFT | wxALIGN_CENTER_VERTICAL, 1);
            {
               S.StartHorizontalLay(wxALIGN_LEFT | wxALIGN_CENTER_VERTICAL, 1);
               {
                  mDraw = S.Id(ID_Draw)
                     .Name(XO("Draw Curves"))
                     .AddRadioButton(XXO("&Draw"));

                  mGraphic = S.Id(ID_Graphic)
                     .Name(XO("Graphic EQ"))
                     .AddRadioButtonToGroup(XXO("&Graphic"));
               }
               S.EndHorizontalLay();
            }
            S.EndHorizontalLay();
         }

         S.StartHorizontalLay(wxALIGN_LEFT | wxALIGN_CENTER_VERTICAL, 0);
         {
            szrH = S.GetSizer();

            S.StartHorizontalLay(wxALIGN_LEFT | wxALIGN_CENTER_VERTICAL, 1);
            {
               szrI = S.GetSizer();

               mInterpChoice = S.Id(ID_Interp)
                  .Name(XO("Interpolation type"))
                  .AddChoice( {},
                     Msgids(kInterpStrings, nInterpolations), 0 );
#if wxUSE_ACCESSIBILITY
               // so that name can be set on a standard control
               mInterpChoice->SetAccessible(safenew WindowAccessible(mInterpChoice));
#endif
            }
            S.EndHorizontalLay();

            S.StartHorizontalLay(wxALIGN_LEFT | wxALIGN_CENTER_VERTICAL, 1);
            {
               szrL = S.GetSizer();

               mLinFreq = S.Id(ID_Linear)
                  .Name(XO("Linear Frequency Scale"))
                  .AddCheckBox(XXO("Li&near Frequency Scale"), false);
            }
            S.EndHorizontalLay();
         }
         S.EndHorizontalLay();

         // -------------------------------------------------------------------
         // Filter length grouping
         // -------------------------------------------------------------------

         if( mOptions == kEqLegacy ){
            S.StartHorizontalLay(wxEXPAND, 0);
            {
               S.StartHorizontalLay(wxALIGN_LEFT | wxALIGN_CENTER_VERTICAL, 0);
               {
                  S.AddPrompt(XXO("Length of &Filter:"));
               }
               S.EndHorizontalLay();

               S.StartHorizontalLay(wxEXPAND, 1);
               {
                  mMSlider = S.Id(ID_Length)
                     .Name(XO("Length of Filter"))
                     .Style(wxSL_HORIZONTAL)
                     .AddSlider( {}, (mM - 1) / 2, 4095, 10);
               }
               S.EndHorizontalLay();

               S.StartHorizontalLay(wxALIGN_LEFT | wxALIGN_CENTER_VERTICAL, 0);
               {
                  wxString label;
                  label.Printf(wxT("%ld"), mM);
                  mMText = S.Name( Verbatim( label ) )
                  // fix for bug 577 (NVDA/Narrator screen readers do not
                  // read static text in dialogs)
                     .AddVariableText( Verbatim( label ) );
               }
               S.EndHorizontalLay();
            }
            S.EndHorizontalLay();

            S.AddSpace(1, 1);
         }

         S.AddSpace(5, 5);

         if( mOptions == kEqLegacy ){
            S.AddSpace(5, 5);
            S.StartHorizontalLay(wxALIGN_RIGHT | wxALIGN_CENTER_VERTICAL);
            {
               S.AddPrompt(XXO("&Select Curve:"));
            }
            S.EndHorizontalLay();

            S.StartHorizontalLay(wxALIGN_LEFT | wxALIGN_CENTER_VERTICAL, 1);
            {
               S.StartHorizontalLay(wxALIGN_LEFT | wxALIGN_CENTER_VERTICAL, 1);
               {
                  mCurve = S.Id(ID_Curve)
                     .Name(XO("Select Curve"))
                     .AddChoice( {},
                        [this]{
                           TranslatableStrings curves;
                           for (const auto &curve : mCurves)
                              curves.push_back( Verbatim( curve.Name ) );
                           return curves;
                        }()
                     );
               }
               S.EndHorizontalLay();
            }
            S.EndHorizontalLay();

            S.Id(ID_Manage).AddButton(XXO("S&ave/Manage Curves..."));
         }

         S.StartHorizontalLay(wxALIGN_LEFT | wxALIGN_CENTER_VERTICAL, 1);
         {
            S.Id(ID_Clear).AddButton(XXO("Fla&tten"));
            S.Id(ID_Invert).AddButton(XXO("&Invert"));

            mGridOnOff = S.Id(ID_Grid)
               .Name(XO("Show grid lines"))
               .AddCheckBox(XXO("Show g&rid lines"), false);
         }
         S.EndHorizontalLay();

         S.AddSpace(5, 5);
      }
      S.EndMultiColumn();
   }
   S.EndMultiColumn();

#ifdef EXPERIMENTAL_EQ_SSE_THREADED
   if (mEffectEqualization48x)
   {
      // -------------------------------------------------------------------
      // ROW 6: Processing routine selection
      // -------------------------------------------------------------------

      // Column 1 is blank
      S.AddSpace(1, 1);

      S.StartHorizontalLay();
      {
         S.AddUnits(XO("&Processing: "));

         // update the control state
         int mathPath = EffectEqualization48x::GetMathPath();
         int value =
            (mathPath & MATH_FUNCTION_SSE)
            ? (mathPath & MATH_FUNCTION_THREADED)
               ? 2
               : 1
            : false // (mathPath & MATH_FUNCTION_AVX) // not implemented
               ? (mathPath & MATH_FUNCTION_THREADED)
                  ? 4
                  : 3
               : 0;

         mMathProcessingType[0] = S.Id(ID_DefaultMath)
            .AddRadioButton(XXO("D&efault"),
                            0, value);
         mMathProcessingType[1] = S.Id(ID_SSE)
            .Disable(!EffectEqualization48x::GetMathCaps()->SSE)
            .AddRadioButtonToGroup(XXO("&SSE"),
                                   1, value);
         mMathProcessingType[2] = S.Id(ID_SSEThreaded)
            .Disable(!EffectEqualization48x::GetMathCaps()->SSE)
            .AddRadioButtonToGroup(XXO("SSE &Threaded"),
                                   2, value);
         mMathProcessingType[3] = S.Id(ID_AVX)
            // not implemented
            .Disable(true /* !EffectEqualization48x::GetMathCaps()->AVX */)
            .AddRadioButtonToGroup(XXO("A&VX"),
                                   3, value);
         mMathProcessingType[4] = S.Id(ID_AVXThreaded)
            // not implemented
            .Disable(true /* !EffectEqualization48x::GetMathCaps()->AVX */)
            .AddRadioButtonToGroup(XXO("AV&X Threaded"),
                                   4, value);
         S.Id(ID_Bench).AddButton(XXO("&Bench"));
      }
      S.EndHorizontalLay();

      // Column 3 is blank
      S.AddSpace(1, 1);
   }
#endif

   mUIParent->SetAutoLayout(false);
   if( mOptions != kEqOptionGraphic)
      mUIParent->Layout();

   if( mOptions == kEqOptionCurve)
      mDrawMode = true;
   if( mOptions == kEqOptionGraphic)
      mDrawMode = false;

   // "show" settings for graphics mode before setting the size of the dialog
   // as this needs more space than draw mode
   szrV->Show(szrG,!mDrawMode);  // eq sliders
   szrH->Show(szrI,true);  // interpolation choice
   szrH->Show(szrL,false); // linear freq checkbox

   if( mOptions == kEqOptionGraphic){
      mPanel->Show( false );
      wxSize sz = szrV->GetMinSize();
      sz += wxSize( 30, 0);
      mUIParent->SetMinSize(sz);
   }
   else{
      mPanel->Show( true );
      szrV->Show(szr1, true);
      // This sizing calculation is hacky.
      // Rather than set the true minimum size we set a size we would 
      // like to have.
      // This makes the default size of the dialog good, but has the 
      // downside that the user can't adjust the dialog smaller.
      wxSize sz = szrV->GetMinSize();
      sz += wxSize( 400, 100);
      szrV->SetMinSize(sz);
   }
   ForceRecalc();

   return nullptr;
}

//
// Populate the window with relevant variables
//
bool EffectEqualization::TransferDataToWindow(const EffectSettings &settings)
{
   // Set log or lin freq scale (affects interpolation as well)
   mLinFreq->SetValue( mLin );
   wxCommandEvent dummyEvent;
   OnLinFreq(dummyEvent);  // causes a CalcFilter

   mGridOnOff->SetValue( mDrawGrid ); // checks/unchecks the box on the interface

   if( mMSlider )
      mMSlider->SetValue((mM - 1) / 2);

   mdBMinSlider->SetValue((int)mdBMin);
   mdBMaxSlider->SetValue((int)mdBMax);

   // Reload the curve names
   UpdateCurves();

   // Set graphic interpolation mode
   mInterpChoice->SetSelection(mInterp);

   // Override draw mode, if we're not displaying the radio buttons.
   if( mOptions == kEqOptionCurve)
      mDrawMode = true;
   if( mOptions == kEqOptionGraphic)
      mDrawMode = false;

   if( mDraw )
      mDraw->SetValue(mDrawMode);
   szrV->Show(szr1,mOptions != kEqOptionGraphic); // Graph
   szrV->Show(szrG,!mDrawMode);    // eq sliders
   szrH->Show(szrI,mOptions == kEqLegacy );    // interpolation choice
   szrH->Show(szrL, mDrawMode);    // linear freq checkbox
   if( mGraphic) 
      mGraphic->SetValue(!mDrawMode);
   mGridOnOff->Show( mDrawMode );

   // Set Graphic (Fader) or Draw mode
   if (!mDrawMode)
      UpdateGraphic();

   UpdateRuler();

   mUIParent->Layout();
   wxGetTopLevelParent(mUIParent)->Layout();

   return true;
}

void EffectEqualization::UpdateRuler()
{
   // Refresh ruler when values have changed
   int w1, w2, h;
   mdBRuler->ruler.GetMaxSize(&w1, &h);
   mdBRuler->ruler.SetRange(mdBMax, mdBMin);
   mdBRuler->ruler.GetMaxSize(&w2, &h);
   if( w1 != w2 )   // Reduces flicker
   {
      mdBRuler->SetSize(wxSize(w2,h));
      mFreqRuler->Refresh(false);
   }
   mdBRuler->Refresh(false);

   mPanel->Refresh(false);
}

// EffectEqualization implementation

bool EffectEqualization::ProcessOne(int count, WaveTrack * t,
                                    sampleCount start, sampleCount len)
{
   // create a NEW WaveTrack to hold all of the output, including 'tails' each end
   auto output = t->EmptyCopy();
   t->ConvertToSampleFormat( floatSample );

   wxASSERT(mM - 1 < windowSize);
   size_t L = windowSize - (mM - 1);   //Process L samples at a go
   auto s = start;
   auto idealBlockLen = t->GetMaxBlockSize() * 4;
   if (idealBlockLen % L != 0)
      idealBlockLen += (L - (idealBlockLen % L));

   Floats buffer{ idealBlockLen };

   Floats window1{ windowSize };
   Floats window2{ windowSize };
   float *thisWindow = window1.get();
   float *lastWindow = window2.get();

   auto originalLen = len;

   for(size_t i = 0; i < windowSize; i++)
      lastWindow[i] = 0;

   TrackProgress(count, 0.);
   bool bLoopSuccess = true;
   size_t wcopy = 0;
   int offset = (mM - 1) / 2;

   while (len != 0)
   {
      auto block = limitSampleBufferSize( idealBlockLen, len );

      t->GetFloats(buffer.get(), s, block);

      for(size_t i = 0; i < block; i += L)   //go through block in lumps of length L
      {
         wcopy = std::min <size_t> (L, block - i);
         for(size_t j = 0; j < wcopy; j++)
            thisWindow[j] = buffer[i+j];   //copy the L (or remaining) samples
         for(auto j = wcopy; j < windowSize; j++)
            thisWindow[j] = 0;   //this includes the padding

         Filter(windowSize, thisWindow);

         // Overlap - Add
         for(size_t j = 0; (j < mM - 1) && (j < wcopy); j++)
            buffer[i+j] = thisWindow[j] + lastWindow[L + j];
         for(size_t j = mM - 1; j < wcopy; j++)
            buffer[i+j] = thisWindow[j];

         std::swap( thisWindow, lastWindow );
      }  //next i, lump of this block

      output->Append((samplePtr)buffer.get(), floatSample, block);
      len -= block;
      s += block;

      if (TrackProgress(count, ( s - start ).as_double() /
                        originalLen.as_double()))
      {
         bLoopSuccess = false;
         break;
      }
   }

   if(bLoopSuccess)
   {
      // mM-1 samples of 'tail' left in lastWindow, get them now
      if(wcopy < (mM - 1)) {
         // Still have some overlap left to process
         // (note that lastWindow and thisWindow have been exchanged at this point
         //  so that 'thisWindow' is really the window prior to 'lastWindow')
         size_t j = 0;
         for(; j < mM - 1 - wcopy; j++)
            buffer[j] = lastWindow[wcopy + j] + thisWindow[L + wcopy + j];
         // And fill in the remainder after the overlap
         for( ; j < mM - 1; j++)
            buffer[j] = lastWindow[wcopy + j];
      } else {
         for(size_t j = 0; j < mM - 1; j++)
            buffer[j] = lastWindow[wcopy + j];
      }
      output->Append((samplePtr)buffer.get(), floatSample, mM - 1);
      output->Flush();

      // now move the appropriate bit of the output back to the track
      // (this could be enhanced in the future to use the tails)
      double offsetT0 = t->LongSamplesToTime(offset);
      double lenT = t->LongSamplesToTime(originalLen);
      // 'start' is the sample offset in 't', the passed in track
      // 'startT' is the equivalent time value
      // 'output' starts at zero
      double startT = t->LongSamplesToTime(start);

      //output has one waveclip for the total length, even though
      //t might have whitespace separating multiple clips
      //we want to maintain the original clip structure, so
      //only paste the intersections of the NEW clip.

      //Find the bits of clips that need replacing
      std::vector<std::pair<double, double> > clipStartEndTimes;
      std::vector<std::pair<double, double> > clipRealStartEndTimes; //the above may be truncated due to a clip being partially selected
      for (const auto &clip : t->GetClips())
      {
         double clipStartT;
         double clipEndT;

         clipStartT = clip->GetPlayStartTime();
         clipEndT = clip->GetPlayEndTime();
         if( clipEndT <= startT )
            continue;   // clip is not within selection
         if( clipStartT >= startT + lenT )
            continue;   // clip is not within selection

         //save the actual clip start/end so that we can rejoin them after we paste.
         clipRealStartEndTimes.push_back(std::pair<double,double>(clipStartT,clipEndT));

         if( clipStartT < startT )  // does selection cover the whole clip?
            clipStartT = startT; // don't copy all the NEW clip
         if( clipEndT > startT + lenT )  // does selection cover the whole clip?
            clipEndT = startT + lenT; // don't copy all the NEW clip

         //save them
         clipStartEndTimes.push_back(std::pair<double,double>(clipStartT,clipEndT));
      }
      //now go thru and replace the old clips with NEW
      for(unsigned int i = 0; i < clipStartEndTimes.size(); i++)
      {
         //remove the old audio and get the NEW
         t->Clear(clipStartEndTimes[i].first,clipStartEndTimes[i].second);
         auto toClipOutput = output->Copy(clipStartEndTimes[i].first-startT+offsetT0,clipStartEndTimes[i].second-startT+offsetT0);
         //put the processed audio in
         t->Paste(clipStartEndTimes[i].first, toClipOutput.get());
         //if the clip was only partially selected, the Paste will have created a split line.  Join is needed to take care of this
         //This is not true when the selection is fully contained within one clip (second half of conditional)
         if( (clipRealStartEndTimes[i].first  != clipStartEndTimes[i].first ||
            clipRealStartEndTimes[i].second != clipStartEndTimes[i].second) &&
            !(clipRealStartEndTimes[i].first <= startT &&
            clipRealStartEndTimes[i].second >= startT+lenT) )
            t->Join(clipRealStartEndTimes[i].first,clipRealStartEndTimes[i].second);
      }
   }

   return bLoopSuccess;
}

bool EffectEqualization::CalcFilter()
{
   double loLog = log10(mLoFreq);
   double hiLog = log10(mHiFreq);
   double denom = hiLog - loLog;

   double delta = mHiFreq / ((double)(mWindowSize / 2.));
   double val0;
   double val1;

   if( IsLinear() )
   {
      val0 = mLinEnvelope->GetValue(0.0);   //no scaling required - saved as dB
      val1 = mLinEnvelope->GetValue(1.0);
   }
   else
   {
      val0 = mLogEnvelope->GetValue(0.0);   //no scaling required - saved as dB
      val1 = mLogEnvelope->GetValue(1.0);
   }
   mFilterFuncR[0] = val0;
   double freq = delta;

   for(size_t i = 1; i <= mWindowSize / 2; i++)
   {
      double when;
      if( IsLinear() )
         when = freq/mHiFreq;
      else
         when = (log10(freq) - loLog)/denom;
      if(when < 0.)
      {
         mFilterFuncR[i] = val0;
      }
      else  if(when > 1.0)
      {
         mFilterFuncR[i] = val1;
      }
      else
      {
         if( IsLinear() )
            mFilterFuncR[i] = mLinEnvelope->GetValue(when);
         else
            mFilterFuncR[i] = mLogEnvelope->GetValue(when);
      }
      freq += delta;
   }
   mFilterFuncR[mWindowSize / 2] = val1;

   mFilterFuncR[0] = DB_TO_LINEAR(mFilterFuncR[0]);

   {
      size_t i = 1;
      for(; i < mWindowSize / 2; i++)
      {
         mFilterFuncR[i] = DB_TO_LINEAR(mFilterFuncR[i]);
         mFilterFuncR[mWindowSize - i] = mFilterFuncR[i];   //Fill entire array
      }
      mFilterFuncR[i] = DB_TO_LINEAR(mFilterFuncR[i]);   //do last one
   }

   //transfer to time domain to do the padding and windowing
   Floats outr{ mWindowSize };
   Floats outi{ mWindowSize };
   InverseRealFFT(mWindowSize, mFilterFuncR.get(), NULL, outr.get()); // To time domain

   {
      size_t i = 0;
      for(; i <= (mM - 1) / 2; i++)
      {  //Windowing - could give a choice, fixed for now - MJS
         //      double mult=0.54-0.46*cos(2*M_PI*(i+(mM-1)/2.0)/(mM-1));   //Hamming
         //Blackman
         double mult =
            0.42 -
            0.5 * cos(2 * M_PI * (i + (mM - 1) / 2.0) / (mM - 1)) +
            .08 * cos(4 * M_PI * (i + (mM - 1) / 2.0) / (mM - 1));
         outr[i] *= mult;
         if(i != 0){
            outr[mWindowSize - i] *= mult;
         }
      }
      for(; i <= mWindowSize / 2; i++)
      {   //Padding
         outr[i] = 0;
         outr[mWindowSize - i] = 0;
      }
   }
   Floats tempr{ mM };
   {
      size_t i = 0;
      for(; i < (mM - 1) / 2; i++)
      {   //shift so that padding on right
         tempr[(mM - 1) / 2 + i] = outr[i];
         tempr[i] = outr[mWindowSize - (mM - 1) / 2 + i];
      }
      tempr[(mM - 1) / 2 + i] = outr[i];
   }

   for (size_t i = 0; i < mM; i++)
   {   //and copy useful values back
      outr[i] = tempr[i];
   }
   for (size_t i = mM; i < mWindowSize; i++)
   {   //rest is padding
      outr[i]=0.;
   }

   //Back to the frequency domain so we can use it
   RealFFT(mWindowSize, outr.get(), mFilterFuncR.get(), mFilterFuncI.get());

   return TRUE;
}

void EffectEqualization::Filter(size_t len, float *buffer)
{
   float re,im;
   // Apply FFT
   RealFFTf(buffer, hFFT.get());
   //FFT(len, false, inr, NULL, outr, outi);

   // Apply filter
   // DC component is purely real
   mFFTBuffer[0] = buffer[0] * mFilterFuncR[0];
   for(size_t i = 1; i < (len / 2); i++)
   {
      re=buffer[hFFT->BitReversed[i]  ];
      im=buffer[hFFT->BitReversed[i]+1];
      mFFTBuffer[2*i  ] = re*mFilterFuncR[i] - im*mFilterFuncI[i];
      mFFTBuffer[2*i+1] = re*mFilterFuncI[i] + im*mFilterFuncR[i];
   }
   // Fs/2 component is purely real
   mFFTBuffer[1] = buffer[1] * mFilterFuncR[len/2];

   // Inverse FFT and normalization
   InverseRealFFTf(mFFTBuffer.get(), hFFT.get());
   ReorderToTime(hFFT.get(), mFFTBuffer.get(), buffer);
}

//
// Load external curves with fallback to default, then message
//
void EffectEqualization::LoadCurves(const wxString &fileName, bool append)
{
// We've disabled the XML management of curves.
// Just going via .cfg files now.
#if 1
   (void)fileName;
   (void)append;
   mCurves.clear();
   mCurves.push_back( wxT("unnamed") );   // we still need a default curve to use
#else
   // Construct normal curve filename
   //
   // LLL:  Wouldn't you know that as of WX 2.6.2, there is a conflict
   //       between wxStandardPaths and wxConfig under Linux.  The latter
   //       creates a normal file as "$HOME/.audacity", while the former
   //       expects the ".audacity" portion to be a directory.
   // MJS:  I don't know what the above means, or if I have broken it.
   wxFileName fn;

   if(fileName.empty()) {
      // Check if presets are up to date.
      wxString eqCurvesCurrentVersion = wxString::Format(wxT("%d.%d"), EQCURVES_VERSION, EQCURVES_REVISION);
      wxString eqCurvesInstalledVersion;
      gPrefs->Read(GetPrefsPrefix() + "PresetVersion", &eqCurvesInstalledVersion, wxT(""));

      bool needUpdate = (eqCurvesCurrentVersion != eqCurvesInstalledVersion);

      // UpdateDefaultCurves allows us to import NEW factory presets only,
      // or update all factory preset curves.
      if (needUpdate)
         UpdateDefaultCurves( UPDATE_ALL != 0 );
      fn = wxFileName( FileNames::DataDir(), wxT("EQCurves.xml") );
   }
   else
      fn = fileName; // user is loading a specific set of curves

   // If requested file doesn't exist...
   if( !fn.FileExists() && !GetDefaultFileName(fn) ) {
      mCurves.clear();
      /* i18n-hint: name of the 'unnamed' custom curve */
      mCurves.push_back( _("unnamed") );   // we still need a default curve to use
      return;
   }

   EQCurve tempCustom(wxT("temp"));
   if( append == false ) // Start from scratch
      mCurves.clear();
   else  // appending so copy and remove 'unnamed', to replace later
   {
      tempCustom.points = mCurves.back().points;
      mCurves.pop_back();
   }

   // Load the curves
   XMLFileReader reader;
   const wxString fullPath{ fn.GetFullPath() };
   if( !reader.Parse( this, fullPath ) )
   {
      /* i18n-hint: EQ stands for 'Equalization'.*/
      auto msg = XO("Error Loading EQ Curves from file:\n%s\nError message says:\n%s")
         .Format( fullPath, reader.GetErrorStr() );
      // Inform user of load failure
      Effect::MessageBox(
         msg,
         wxOK | wxCENTRE,
         XO("Error Loading EQ Curves") );
      mCurves.push_back( _("unnamed") );  // we always need a default curve to use
      return;
   }

   // Move "unnamed" to end, if it exists in current language.
   int numCurves = mCurves.size();
   int curve;
   EQCurve tempUnnamed(wxT("tempUnnamed"));
   for( curve = 0; curve < numCurves-1; curve++ )
   {
      if( mCurves[curve].Name == _("unnamed") )
      {
         tempUnnamed.points = mCurves[curve].points;
         mCurves.erase(mCurves.begin() + curve);
         mCurves.push_back( _("unnamed") );   // add 'unnamed' back at the end
         mCurves.back().points = tempUnnamed.points;
      }
   }

   if( mCurves.back().Name != _("unnamed") )
      mCurves.push_back( _("unnamed") );   // we always need a default curve to use
   if( append == true )
   {
      mCurves.back().points = tempCustom.points;
   }
#endif
   return;
}

//
// Update presets to match Audacity version.
//
void EffectEqualization::UpdateDefaultCurves(bool updateAll /* false */)
{
   if (mCurves.size() == 0)
      return;

   wxString unnamed = wxT("unnamed");

   // Save the "unnamed" curve and remove it so we can add it back as the final curve.
   EQCurve userUnnamed(wxT("temp"));
   userUnnamed = mCurves.back();
   mCurves.pop_back();

   EQCurveArray userCurves = mCurves;
   mCurves.clear();
   // We only wamt to look for the shipped EQDefaultCurves.xml
   wxFileName fn = wxFileName(FileNames::ResourcesDir(), wxT("EQDefaultCurves.xml"));
   wxLogDebug(wxT("Attempting to load EQDefaultCurves.xml from %s"),fn.GetFullPath());
   XMLFileReader reader;

   if(!reader.Parse(this, fn.GetFullPath())) {
      wxLogError(wxT("EQDefaultCurves.xml could not be read."));
      return;
   }
   else {
      wxLogDebug(wxT("Loading EQDefaultCurves.xml successful."));
   }

   EQCurveArray defaultCurves = mCurves;
   mCurves.clear(); // clear now so that we can sort then add back.

   // Remove "unnamed" if it exists.
   if (defaultCurves.back().Name == unnamed) {
      defaultCurves.pop_back();
   }
   else {
      wxLogError(wxT("Error in EQDefaultCurves.xml"));
   }

   int numUserCurves = userCurves.size();
   int numDefaultCurves = defaultCurves.size();
   EQCurve tempCurve(wxT("test"));

   if (updateAll) {
      // Update all factory preset curves.
      // Sort and add factory defaults first;
      mCurves = defaultCurves;
      std::sort(mCurves.begin(), mCurves.end());
      // then add remaining user curves:
      for (int curveCount = 0; curveCount < numUserCurves; curveCount++) {
         bool isCustom = true;
         tempCurve = userCurves[curveCount];
         // is the name in the default set?
         for (int defCurveCount = 0; defCurveCount < numDefaultCurves; defCurveCount++) {
            if (tempCurve.Name == mCurves[defCurveCount].Name) {
               isCustom = false;
               break;
            }
         }
         // if tempCurve is not in the default set, add it to mCurves.
         if (isCustom) {
            mCurves.push_back(tempCurve);
         }
      }
   }
   else {
      // Import NEW factory defaults but retain all user modified curves.
      for (int defCurveCount = 0; defCurveCount < numDefaultCurves; defCurveCount++) {
         bool isUserCurve = false;
         // Add if the curve is in the user's set (preserve user's copy)
         for (int userCurveCount = 0; userCurveCount < numUserCurves; userCurveCount++) {
            if (userCurves[userCurveCount].Name == defaultCurves[defCurveCount].Name) {
               isUserCurve = true;
               mCurves.push_back(userCurves[userCurveCount]);
               break;
            }
         }
         if (!isUserCurve) {
            mCurves.push_back(defaultCurves[defCurveCount]);
         }
      }
      std::sort(mCurves.begin(), mCurves.end());
      // now add the rest of the user's curves.
      for (int userCurveCount = 0; userCurveCount < numUserCurves; userCurveCount++) {
         bool isDefaultCurve = false;
         tempCurve = userCurves[userCurveCount];
         for (int defCurveCount = 0; defCurveCount < numDefaultCurves; defCurveCount++) {
            if (tempCurve.Name == defaultCurves[defCurveCount].Name) {
               isDefaultCurve = true;
               break;
            }
         }
         if (!isDefaultCurve) {
            mCurves.push_back(tempCurve);
         }
      }
   }
   defaultCurves.clear();
   userCurves.clear();

   // Add back old "unnamed"
   if(userUnnamed.Name == unnamed) {
      mCurves.push_back( userUnnamed );   // we always need a default curve to use
   }

   SaveCurves();

   // Write current EqCurve version number
   // TODO: Probably better if we used pluginregistry.cfg
   wxString eqCurvesCurrentVersion = wxString::Format(wxT("%d.%d"), EQCURVES_VERSION, EQCURVES_REVISION);
   gPrefs->Write(GetPrefsPrefix()+"PresetVersion", eqCurvesCurrentVersion);
   gPrefs->Flush();

   return;
}

//
// Get fully qualified filename of EQDefaultCurves.xml
//
bool EffectEqualization::GetDefaultFileName(wxFileName &fileName)
{
   // look in data dir first, in case the user has their own defaults (maybe downloaded ones)
   fileName = wxFileName( FileNames::DataDir(), wxT("EQDefaultCurves.xml") );
   if( !fileName.FileExists() )
   {  // Default file not found in the data dir.  Fall back to Resources dir.
      // See http://docs.wxwidgets.org/trunk/classwx_standard_paths.html#5514bf6288ee9f5a0acaf065762ad95d
      fileName = wxFileName( FileNames::ResourcesDir(), wxT("EQDefaultCurves.xml") );
   }
   if( !fileName.FileExists() )
   {
      // LLL:  Is there really a need for an error message at all???
      //auto errorMessage = XO("EQCurves.xml and EQDefaultCurves.xml were not found on your system.\nPlease press 'help' to visit the download page.\n\nSave the curves at %s")
      //   .Format( FileNames::DataDir() );
      //BasicUI::ShowErrorDialog( wxWidgetsWindowPlacement{ mUIParent },
      //   XO("EQCurves.xml and EQDefaultCurves.xml missing"),
      //   errorMessage, wxT("http://wiki.audacityteam.org/wiki/EQCurvesDownload"), false);

      // Have another go at finding EQCurves.xml in the data dir, in case 'help' helped
      fileName = wxFileName( FileNames::DataDir(), wxT("EQDefaultCurves.xml") );
   }
   return (fileName.FileExists());
}


//
// Save curves to external file
//
void EffectEqualization::SaveCurves(const wxString &fileName)
{
   wxFileName fn;
   if( fileName.empty() )
   {
      // Construct default curve filename
      //
      // LLL:  Wouldn't you know that as of WX 2.6.2, there is a conflict
      //       between wxStandardPaths and wxConfig under Linux.  The latter
      //       creates a normal file as "$HOME/.audacity", while the former
      //       expects the ".audacity" portion to be a directory.
      fn = wxFileName( FileNames::DataDir(), wxT("EQCurves.xml") );

      // If the directory doesn't exist...
      if( !fn.DirExists() )
      {
         // Attempt to create it
         if( !fn.Mkdir( fn.GetPath(), 511, wxPATH_MKDIR_FULL ) )
         {
            // MkDir() will emit message
            return;
         }
      }
   }
   else
      fn = fileName;

   GuardedCall( [&] {
      // Create/Open the file
      const wxString fullPath{ fn.GetFullPath() };
      XMLFileWriter eqFile{ fullPath, XO("Error Saving Equalization Curves") };

      // Write the curves
      WriteXML( eqFile );

      eqFile.Commit();
   } );
}

//
// Make the passed curve index the active one
//
void EffectEqualization::setCurve(int currentCurve)
{
   // Set current choice
   wxASSERT( currentCurve < (int) mCurves.size() );
   Select(currentCurve);

   Envelope *env;
   int numPoints = (int) mCurves[currentCurve].points.size();

   if (mLin) {  // linear freq mode
      env = mLinEnvelope.get();
   }
   else { // log freq mode
      env = mLogEnvelope.get();
   }
   env->Flatten(0.);
   env->SetTrackLen(1.0);

   // Handle special case of no points.
   if (numPoints == 0) {
      ForceRecalc();
      return;
   }

   double when, value;

   // Handle special case 1 point.
   if (numPoints == 1) {
      // only one point, so ensure it is in range then return.
      when = mCurves[currentCurve].points[0].Freq;
      if (mLin) {
         when = when / mHiFreq;
      }
      else {   // log scale
         // We don't go below loFreqI (20 Hz) in log view.
         double loLog = log10((double)loFreqI);
         double hiLog = log10(mHiFreq);
         double denom = hiLog - loLog;
         when = (log10(std::max((double) loFreqI, when)) - loLog)/denom;
      }
      value = mCurves[currentCurve].points[0].dB;
      env->Insert(std::min(1.0, std::max(0.0, when)), value);
      ForceRecalc();
      return;
   }

   // We have at least two points, so ensure they are in frequency order.
   std::sort(mCurves[currentCurve].points.begin(),
             mCurves[currentCurve].points.end());

   if (mCurves[currentCurve].points[0].Freq < 0) {
      // Corrupt or invalid curve, so bail.
      ForceRecalc();
      return;
   }

   if(mLin) {   // linear Hz scale
      for(int pointCount = 0; pointCount < numPoints; pointCount++) {
         when = mCurves[currentCurve].points[pointCount].Freq / mHiFreq;
         value = mCurves[currentCurve].points[pointCount].dB;
         if(when <= 1) {
            env->Insert(when, value);
            if (when == 1)
               break;
         }
         else {
            // There are more points at higher freqs,
            // so interpolate next one then stop.
            when = 1.0;
            double nextDB = mCurves[currentCurve].points[pointCount].dB;
            if (pointCount > 0) {
               double nextF = mCurves[currentCurve].points[pointCount].Freq;
               double lastF = mCurves[currentCurve].points[pointCount-1].Freq;
               double lastDB = mCurves[currentCurve].points[pointCount-1].dB;
               value = lastDB +
                  ((nextDB - lastDB) *
                     ((mHiFreq - lastF) / (nextF - lastF)));
            }
            else
               value = nextDB;
            env->Insert(when, value);
            break;
         }
      }
   }
   else {   // log Hz scale
      double loLog = log10((double) loFreqI);
      double hiLog = log10(mHiFreq);
      double denom = hiLog - loLog;
      int firstAbove20Hz;

      // log scale EQ starts at 20 Hz (threshold of hearing).
      // so find the first point (if any) above 20 Hz.
      for (firstAbove20Hz = 0; firstAbove20Hz < numPoints; firstAbove20Hz++) {
         if (mCurves[currentCurve].points[firstAbove20Hz].Freq > loFreqI)
            break;
      }

      if (firstAbove20Hz == numPoints) {
         // All points below 20 Hz, so just use final point.
         when = 0.0;
         value = mCurves[currentCurve].points[numPoints-1].dB;
         env->Insert(when, value);
         ForceRecalc();
         return;
      }

      if (firstAbove20Hz > 0) {
         // At least one point is before 20 Hz and there are more
         // beyond 20 Hz, so interpolate the first
         double prevF = mCurves[currentCurve].points[firstAbove20Hz-1].Freq;
         prevF = log10(std::max(1.0, prevF)); // log zero is bad.
         double prevDB = mCurves[currentCurve].points[firstAbove20Hz-1].dB;
         double nextF = log10(mCurves[currentCurve].points[firstAbove20Hz].Freq);
         double nextDB = mCurves[currentCurve].points[firstAbove20Hz].dB;
         when = 0.0;
         value = nextDB - ((nextDB - prevDB) * ((nextF - loLog) / (nextF - prevF)));
         env->Insert(when, value);
      }

      // Now get the rest.
      for(int pointCount = firstAbove20Hz; pointCount < numPoints; pointCount++)
      {
         double flog = log10(mCurves[currentCurve].points[pointCount].Freq);
         wxASSERT(mCurves[currentCurve].points[pointCount].Freq >= loFreqI);

         when = (flog - loLog)/denom;
         value = mCurves[currentCurve].points[pointCount].dB;
         if(when <= 1.0) {
            env->Insert(when, value);
         }
         else {
            // This looks weird when adjusting curve in Draw mode if
            // there is a point off-screen.

            /*
            // we have a point beyond fs/2.  Insert it so that env code can use it.
            // but just this one, we have no use for the rest
            env->SetTrackLen(when); // can't Insert if the envelope isn't long enough
            env->Insert(when, value);
            break;
            */

            // interpolate the final point instead
            when = 1.0;
            if (pointCount > 0) {
               double lastDB = mCurves[currentCurve].points[pointCount-1].dB;
               double logLastF =
                  log10(mCurves[currentCurve].points[pointCount-1].Freq);
               value = lastDB +
                  ((value - lastDB) *
                     ((log10(mHiFreq) - logLastF) / (flog - logLastF)));
            }
            env->Insert(when, value);
            break;
         }
      }
   }
   ForceRecalc();
}

void EffectEqualization::setCurve()
{
   setCurve((int) mCurves.size() - 1);
}

void EffectEqualization::setCurve(const wxString &curveName)
{
   unsigned i = 0;
   for( i = 0; i < mCurves.size(); i++ )
      if( curveName == mCurves[ i ].Name )
         break;
   if( i == mCurves.size())
   {
      Effect::MessageBox(
         XO("Requested curve not found, using 'unnamed'"),
         wxOK|wxICON_ERROR,
         XO("Curve not found") );
      setCurve();
   }
   else
      setCurve( i );
}

//
// Set NEW curve selection (safe to call outside of the UI)
//
void EffectEqualization::Select( int curve )
{
   // Set current choice
   if (mCurve)
   {
      mCurve->SetSelection( curve );
      mCurveName = mCurves[ curve ].Name;
   }
}

//
// Tell panel to recalc (safe to call outside of UI)
//
void EffectEqualization::ForceRecalc()
{
   if (mPanel)
   {
      mPanel->ForceRecalc();
   }
}

//
// Capture updated envelope
//
void EffectEqualization::EnvelopeUpdated()
{
   if (IsLinear())
   {
      EnvelopeUpdated(mLinEnvelope.get(), true);
   }
   else
   {
      EnvelopeUpdated(mLogEnvelope.get(), false);
   }
}

void EffectEqualization::EnvelopeUpdated(Envelope *env, bool lin)
{
   // Allocate and populate point arrays
   size_t numPoints = env->GetNumberOfPoints();
   Doubles when{ numPoints };
   Doubles value{ numPoints };
   env->GetPoints( when.get(), value.get(), numPoints );

   // Clear the unnamed curve
   int curve = mCurves.size() - 1;
   mCurves[ curve ].points.clear();

   if(lin)
   {
      // Copy and convert points
      for (size_t point = 0; point < numPoints; point++)
      {
         double freq = when[ point ] * mHiFreq;
         double db = value[ point ];

         // Add it to the curve
         mCurves[ curve ].points.push_back( EQPoint( freq, db ) );
      }
   }
   else
   {
      double loLog = log10( 20. );
      double hiLog = log10( mHiFreq );
      double denom = hiLog - loLog;

      // Copy and convert points
      for (size_t point = 0; point < numPoints; point++)
      {
         double freq = pow( 10., ( ( when[ point ] * denom ) + loLog ));
         double db = value[ point ];

         // Add it to the curve
         mCurves[ curve ].points.push_back( EQPoint( freq, db ) );
      }
   }
   // Remember that we've updated the unnamed curve
   mDirty = true;

   // set 'unnamed' as the selected curve
   Select( (int) mCurves.size() - 1 );
}

//
//
//
bool EffectEqualization::IsLinear()
{
   return mDrawMode && mLin;
}

//
// Flatten the curve
//
void EffectEqualization::Flatten()
{
   mLogEnvelope->Flatten(0.);
   mLogEnvelope->SetTrackLen(1.0);
   mLinEnvelope->Flatten(0.);
   mLinEnvelope->SetTrackLen(1.0);
   ForceRecalc();
   if( !mDrawMode )
   {
      for( size_t i = 0; i < mBandsInUse; i++)
      {
         mSliders[i]->SetValue(0);
         mSlidersOld[i] = 0;
         mEQVals[i] = 0.;

         wxString tip;
         if( kThirdOct[i] < 1000.)
            tip.Printf( wxT("%dHz\n%.1fdB"), (int)kThirdOct[i], 0. );
         else
            tip.Printf( wxT("%gkHz\n%.1fdB"), kThirdOct[i]/1000., 0. );
         mSliders[i]->SetToolTip(tip);
      }
   }
   EnvelopeUpdated();
}

//
// Process XML tags and handle the ones we recognize
//
bool EffectEqualization::HandleXMLTag(const std::string_view& tag, const AttributesList &attrs)
{
   // May want to add a version strings...
   if (tag == "equalizationeffect")
   {
      return true;
   }

   // Located a NEW curve
   if (tag == "curve")
   {
      // Process the attributes
      for (auto pair : attrs)
      {
         auto attr = pair.first;
         auto value = pair.second;

         // Create a NEW curve and name it
         if( attr == "name" )
         {
            const wxString strValue = value.ToWString();
            // check for a duplicate name and add (n) if there is one
            int n = 0;
            wxString strValueTemp = strValue;
            bool exists;
            do
            {
               exists = false;
               for(size_t i = 0; i < mCurves.size(); i++)
               {
                  if(n>0)
                     strValueTemp.Printf(wxT("%s (%d)"),strValue,n);
                  if(mCurves[i].Name == strValueTemp)
                  {
                     exists = true;
                     break;
                  }
               }
               n++;
            }
            while(exists == true);

            mCurves.push_back( EQCurve( strValueTemp ) );
         }
      }

      // Tell caller it was processed
      return true;
   }

   // Located a NEW point
   if(tag == "point")
   {
      // Set defaults in case attributes are missing
      double f = 0.0;
      double d = 0.0;

      // Process the attributes
      double dblValue;
      for (auto pair : attrs)
      {
         auto attr = pair.first;
         auto value = pair.second;

         // Get the frequency
         if( attr == "f" )
         {
            if (!value.TryGet(dblValue))
               return false;
            f = dblValue;
         }
         // Get the dB
         else if( attr == "d" )
         {
            if (!value.TryGet(dblValue))
               return false;
            d = dblValue;
         }
      }

      // Create a NEW point
      mCurves[ mCurves.size() - 1 ].points.push_back( EQPoint( f, d ) );

      // Tell caller it was processed
      return true;
   }

   // Tell caller we didn't understand the tag
   return false;
}

//
// Return handler for recognized tags
//
XMLTagHandler *EffectEqualization::HandleXMLChild(const std::string_view& tag)
{
   if (tag == "equalizationeffect")
   {
      return this;
   }

   if (tag == "curve")
   {
      return this;
   }

   if (tag == "point")
   {
      return this;
   }

   return NULL;
}

//
// Write all of the curves to the XML file
//
void EffectEqualization::WriteXML(XMLWriter &xmlFile) const
// may throw
{
   // Start our hierarchy
   xmlFile.StartTag( wxT( "equalizationeffect" ) );

   // Write all curves
   int numCurves = mCurves.size();
   int curve;
   for( curve = 0; curve < numCurves; curve++ )
   {
      // Start a NEW curve
      xmlFile.StartTag( wxT( "curve" ) );
      xmlFile.WriteAttr( wxT( "name" ), mCurves[ curve ].Name );

      // Write all points
      int numPoints = mCurves[ curve ].points.size();
      int point;
      for( point = 0; point < numPoints; point++ )
      {
         // Write NEW point
         xmlFile.StartTag( wxT( "point" ) );
         xmlFile.WriteAttr( wxT( "f" ), mCurves[ curve ].points[ point ].Freq, 12 );
         xmlFile.WriteAttr( wxT( "d" ), mCurves[ curve ].points[ point ].dB, 12 );
         xmlFile.EndTag( wxT( "point" ) );
      }

      // Terminate curve
      xmlFile.EndTag( wxT( "curve" ) );
   }

   // Terminate our hierarchy
   xmlFile.EndTag( wxT( "equalizationeffect" ) );
}

///////////////////////////////////////////////////////////////////////////////
//
// All EffectEqualization methods beyond this point interact with the UI, so
// can't be called while the UI is not displayed.
//
///////////////////////////////////////////////////////////////////////////////

void EffectEqualization::UpdateCurves()
{

   // Reload the curve names
   if( mCurve ) 
      mCurve->Clear();
   bool selectedCurveExists = false;
   for (size_t i = 0, cnt = mCurves.size(); i < cnt; i++)
   {
      if (mCurveName == mCurves[ i ].Name)
         selectedCurveExists = true;
      if( mCurve ) 
         mCurve->Append(mCurves[ i ].Name);
   }
   // In rare circumstances, mCurveName may not exist (bug 1891)
   if (!selectedCurveExists)
      mCurveName = mCurves[ (int)mCurves.size() - 1 ].Name;
   if( mCurve ) 
      mCurve->SetStringSelection(mCurveName);
   
   // Allow the control to resize
   if( mCurve ) 
      mCurve->SetMinSize({-1, -1});

   // Set initial curve
   setCurve( mCurveName );
}

void EffectEqualization::UpdateDraw()
{
   size_t numPoints = mLogEnvelope->GetNumberOfPoints();
   Doubles when{ numPoints };
   Doubles value{ numPoints };
   double deltadB = 0.1;
   double dx, dy, dx1, dy1, err;

   mLogEnvelope->GetPoints( when.get(), value.get(), numPoints );

   // set 'unnamed' as the selected curve
   EnvelopeUpdated();

   bool flag = true;
   while (flag)
   {
      flag = false;
      int numDeleted = 0;
      mLogEnvelope->GetPoints( when.get(), value.get(), numPoints );
      for (size_t j = 0; j + 2 < numPoints; j++)
      {
         dx = when[j+2+numDeleted] - when[j+numDeleted];
         dy = value[j+2+numDeleted] - value[j+numDeleted];
         dx1 = when[j+numDeleted+1] - when[j+numDeleted];
         dy1 = dy * dx1 / dx;
         err = fabs(value[j+numDeleted+1] - (value[j+numDeleted] + dy1));
         if( err < deltadB )
         {   // within < deltadB dB?
            mLogEnvelope->Delete(j+1);
            numPoints--;
            numDeleted++;
            flag = true;
         }
      }
   }

   if(mLin) // do not use IsLinear() here
   {
      EnvLogToLin();
      mEnvelope = mLinEnvelope.get();
      mFreqRuler->ruler.SetLog(false);
      mFreqRuler->ruler.SetRange(0, mHiFreq);
   }

   szrV->Show(szrG,false);
   szrH->Show(szrI,false);
   szrH->Show(szrL,true);

   mUIParent->Layout();
   wxGetTopLevelParent(mUIParent)->Layout();
   ForceRecalc();     // it may have changed slightly due to the deletion of points
}

void EffectEqualization::UpdateGraphic()
{
   double loLog = log10(mLoFreq);
   double hiLog = log10(mHiFreq);
   double denom = hiLog - loLog;

   if(mLin)  //going from lin to log freq scale - do not use IsLinear() here
   {  // add some extra points to the linear envelope for the graphic to follow
      double step = pow(2., 1./12.);   // twelve steps per octave
      double when,value;
      for(double freq=10.; freq<mHiFreq; freq*=step)
      {
         when = freq/mHiFreq;
         value = mLinEnvelope->GetValue(when);
         mLinEnvelope->Insert(when, value);
      }

      EnvLinToLog();
      mEnvelope = mLogEnvelope.get();
      mFreqRuler->ruler.SetLog(true);
      mFreqRuler->ruler.SetRange(mLoFreq, mHiFreq);
   }

   for (size_t i = 0; i < mBandsInUse; i++)
   {
      if( kThirdOct[i] == mLoFreq )
         mWhenSliders[i] = 0.;
      else
         mWhenSliders[i] = (log10(kThirdOct[i])-loLog)/denom;
      mEQVals[i] = mLogEnvelope->GetValue(mWhenSliders[i]);    //set initial values of sliders
      if( mEQVals[i] > 20.)
         mEQVals[i] = 20.;
      if( mEQVals[i] < -20.)
         mEQVals[i] = -20.;
   }
   ErrMin();                  //move sliders to minimise error
   for (size_t i = 0; i < mBandsInUse; i++)
   {
      mSliders[i]->SetValue(lrint(mEQVals[i])); //actually set slider positions
      mSlidersOld[i] = mSliders[i]->GetValue();
      wxString tip;
      if( kThirdOct[i] < 1000.)
         tip.Printf( wxT("%dHz\n%.1fdB"), (int)kThirdOct[i], mEQVals[i] );
      else
         tip.Printf( wxT("%gkHz\n%.1fdB"), kThirdOct[i]/1000., mEQVals[i] );
      mSliders[i]->SetToolTip(tip);
   }

   szrV->Show(szrG,true);  // eq sliders
   szrH->Show(szrI,mOptions == kEqLegacy );  // interpolation choice
   szrH->Show(szrL,false); // linear freq checkbox

   mUIParent->Layout();
   wxGetTopLevelParent(mUIParent)->Layout();
   mUIParent->Layout();
   wxGetTopLevelParent(mUIParent)->Layout();

   GraphicEQ(mLogEnvelope.get());
   mDrawMode = false;
}

void EffectEqualization::EnvLogToLin(void)
{
   size_t numPoints = mLogEnvelope->GetNumberOfPoints();
   if( numPoints == 0 )
   {
      return;
   }

   Doubles when{ numPoints };
   Doubles value{ numPoints };

   mLinEnvelope->Flatten(0.);
   mLinEnvelope->SetTrackLen(1.0);
   mLogEnvelope->GetPoints( when.get(), value.get(), numPoints );
   mLinEnvelope->Reassign(0., value[0]);
   double loLog = log10(20.);
   double hiLog = log10(mHiFreq);
   double denom = hiLog - loLog;

   for (size_t i = 0; i < numPoints; i++)
      mLinEnvelope->Insert(pow( 10., ((when[i] * denom) + loLog))/mHiFreq , value[i]);
   mLinEnvelope->Reassign(1., value[numPoints-1]);
}

void EffectEqualization::EnvLinToLog(void)
{
   size_t numPoints = mLinEnvelope->GetNumberOfPoints();
   if( numPoints == 0 )
   {
      return;
   }

   Doubles when{ numPoints };
   Doubles value{ numPoints };

   mLogEnvelope->Flatten(0.);
   mLogEnvelope->SetTrackLen(1.0);
   mLinEnvelope->GetPoints( when.get(), value.get(), numPoints );
   mLogEnvelope->Reassign(0., value[0]);
   double loLog = log10(20.);
   double hiLog = log10(mHiFreq);
   double denom = hiLog - loLog;
   bool changed = false;

   for (size_t i = 0; i < numPoints; i++)
   {
      if( when[i]*mHiFreq >= 20 )
      {
         // Caution: on Linux, when when == 20, the log calculation rounds
         // to just under zero, which causes an assert error.
         double flog = (log10(when[i]*mHiFreq)-loLog)/denom;
         mLogEnvelope->Insert(std::max(0.0, flog) , value[i]);
      }
      else
      {  //get the first point as close as we can to the last point requested
         changed = true;
         double v = value[i];
         mLogEnvelope->Insert(0., v);
      }
   }
   mLogEnvelope->Reassign(1., value[numPoints - 1]);

   if(changed)
      EnvelopeUpdated(mLogEnvelope.get(), false);
}

void EffectEqualization::ErrMin(void)
{
   double vals[NUM_PTS];
   double error = 0.0;
   double oldError = 0.0;
   double mEQValsOld = 0.0;
   double correction = 1.6;
   bool flag;
   size_t j=0;
   Envelope testEnvelope{ *mLogEnvelope };

   for(size_t i = 0; i < NUM_PTS; i++)
      vals[i] = testEnvelope.GetValue(mWhens[i]);

   //   Do error minimisation
   error = 0.;
   GraphicEQ(&testEnvelope);
   for(size_t i = 0; i < NUM_PTS; i++)   //calc initial error
   {
      double err = vals[i] - testEnvelope.GetValue(mWhens[i]);
      error += err*err;
   }
   oldError = error;
   while( j < mBandsInUse*12 )  //loop over the sliders a number of times
   {
      auto i = j % mBandsInUse;       //use this slider
      if( (j > 0) & (i == 0) )   // if we've come back to the first slider again...
      {
         if( correction > 0 )
            correction = -correction;     //go down
         else
            correction = -correction/2.;  //go up half as much
      }
      flag = true;   // check if we've hit the slider limit
      do
      {
         oldError = error;
         mEQValsOld = mEQVals[i];
         mEQVals[i] += correction;    //move fader value
         if( mEQVals[i] > 20. )
         {
            mEQVals[i] = 20.;
            flag = false;
         }
         if( mEQVals[i] < -20. )
         {
            mEQVals[i] = -20.;
            flag = false;
         }
         GraphicEQ(&testEnvelope);         //calculate envelope
         error = 0.;
         for(size_t k = 0; k < NUM_PTS; k++)  //calculate error
         {
            double err = vals[k] - testEnvelope.GetValue(mWhens[k]);
            error += err*err;
         }
      }
      while( (error < oldError) && flag );
      if( error > oldError )
      {
         mEQVals[i] = mEQValsOld;   //last one didn't work
         error = oldError;
      }
      else
         oldError = error;
      if( error < .0025 * mBandsInUse)
         break;   // close enuff
      j++;  //try next slider
   }
   if( error > .0025 * mBandsInUse ) // not within 0.05dB on each slider, on average
   {
      Select( (int) mCurves.size() - 1 );
      EnvelopeUpdated(&testEnvelope, false);
   }
}

void EffectEqualization::GraphicEQ(Envelope *env)
{
   // JKC: 'value' is for height of curve.
   // The 0.0 initial value would only get used if NUM_PTS were 0.
   double value = 0.0;
   double dist, span, s;

   env->Flatten(0.);
   env->SetTrackLen(1.0);

   switch( mInterp )
   {
   case kBspline:  // B-spline
      {
         int minF = 0;
         for(size_t i = 0; i < NUM_PTS; i++)
         {
            while( (mWhenSliders[minF] <= mWhens[i]) & (minF < (int)mBandsInUse) )
               minF++;
            minF--;
            if( minF < 0 ) //before first slider
            {
               dist = mWhens[i] - mWhenSliders[0];
               span = mWhenSliders[1] - mWhenSliders[0];
               s = dist/span;
               if( s < -1.5 )
                  value = 0.;
               else if( s < -.5 )
                  value = mEQVals[0]*(s + 1.5)*(s + 1.5)/2.;
               else
                  value = mEQVals[0]*(.75 - s*s) + mEQVals[1]*(s + .5)*(s + .5)/2.;
            }
            else
            {
               if( mWhens[i] > mWhenSliders[mBandsInUse-1] )   //after last fader
               {
                  dist = mWhens[i] - mWhenSliders[mBandsInUse-1];
                  span = mWhenSliders[mBandsInUse-1] - mWhenSliders[mBandsInUse-2];
                  s = dist/span;
                  if( s > 1.5 )
                     value = 0.;
                  else if( s > .5 )
                     value = mEQVals[mBandsInUse-1]*(s - 1.5)*(s - 1.5)/2.;
                  else
                     value = mEQVals[mBandsInUse-1]*(.75 - s*s) +
                     mEQVals[mBandsInUse-2]*(s - .5)*(s - .5)/2.;
               }
               else  //normal case
               {
                  dist = mWhens[i] - mWhenSliders[minF];
                  span = mWhenSliders[minF+1] - mWhenSliders[minF];
                  s = dist/span;
                  if(s < .5 )
                  {
                     value = mEQVals[minF]*(0.75 - s*s);
                     if( minF+1 < (int)mBandsInUse )
                        value += mEQVals[minF+1]*(s+.5)*(s+.5)/2.;
                     if( minF-1 >= 0 )
                        value += mEQVals[minF-1]*(s-.5)*(s-.5)/2.;
                  }
                  else
                  {
                     value = mEQVals[minF]*(s-1.5)*(s-1.5)/2.;
                     if( minF+1 < (int)mBandsInUse )
                        value += mEQVals[minF+1]*(.75-(1.-s)*(1.-s));
                     if( minF+2 < (int)mBandsInUse )
                        value += mEQVals[minF+2]*(s-.5)*(s-.5)/2.;
                  }
               }
            }
            if(mWhens[i]<=0.)
               env->Reassign(0., value);
            env->Insert( mWhens[i], value );
         }
         env->Reassign( 1., value );
         break;
      }

   case kCosine:  // Cosine squared
      {
         int minF = 0;
         for(size_t i = 0; i < NUM_PTS; i++)
         {
            while( (mWhenSliders[minF] <= mWhens[i]) & (minF < (int)mBandsInUse) )
               minF++;
            minF--;
            if( minF < 0 ) //before first slider
            {
               dist = mWhenSliders[0] - mWhens[i];
               span = mWhenSliders[1] - mWhenSliders[0];
               if( dist < span )
                  value = mEQVals[0]*(1. + cos(M_PI*dist/span))/2.;
               else
                  value = 0.;
            }
            else
            {
               if( mWhens[i] > mWhenSliders[mBandsInUse-1] )   //after last fader
               {
                  span = mWhenSliders[mBandsInUse-1] - mWhenSliders[mBandsInUse-2];
                  dist = mWhens[i] - mWhenSliders[mBandsInUse-1];
                  if( dist < span )
                     value = mEQVals[mBandsInUse-1]*(1. + cos(M_PI*dist/span))/2.;
                  else
                     value = 0.;
               }
               else  //normal case
               {
                  span = mWhenSliders[minF+1] - mWhenSliders[minF];
                  dist = mWhenSliders[minF+1] - mWhens[i];
                  value = mEQVals[minF]*(1. + cos(M_PI*(span-dist)/span))/2. +
                     mEQVals[minF+1]*(1. + cos(M_PI*dist/span))/2.;
               }
            }
            if(mWhens[i]<=0.)
               env->Reassign(0., value);
            env->Insert( mWhens[i], value );
         }
         env->Reassign( 1., value );
         break;
      }

   case kCubic:  // Cubic Spline
      {
         double y2[NUMBER_OF_BANDS+1];
         mEQVals[mBandsInUse] = mEQVals[mBandsInUse-1];
         spline(mWhenSliders, mEQVals, mBandsInUse+1, y2);
         for(double xf=0; xf<1.; xf+=1./NUM_PTS)
         {
            env->Insert(xf, splint(mWhenSliders, mEQVals, mBandsInUse+1, y2, xf));
         }
         break;
      }
   }

   ForceRecalc();
}

void EffectEqualization::spline(double x[], double y[], size_t n, double y2[])
{
   wxASSERT( n > 0 );

   double p, sig;
   Doubles u{ n };

   y2[0] = 0.;  //
   u[0] = 0.;   //'natural' boundary conditions
   for (size_t i = 1; i + 1 < n; i++)
   {
      sig = ( x[i] - x[i-1] ) / ( x[i+1] - x[i-1] );
      p = sig * y2[i-1] + 2.;
      y2[i] = (sig - 1.)/p;
      u[i] = ( y[i+1] - y[i] ) / ( x[i+1] - x[i] ) - ( y[i] - y[i-1] ) / ( x[i] - x[i-1] );
      u[i] = (6.*u[i]/( x[i+1] - x[i-1] ) - sig * u[i-1]) / p;
   }
   y2[n - 1] = 0.;
   for (size_t i = n - 1; i--;)
      y2[i] = y2[i]*y2[i+1] + u[i];
}

double EffectEqualization::splint(double x[], double y[], size_t n, double y2[], double xr)
{
   wxASSERT( n > 1 );

   double a, b, h;
   static double xlast = 0.;   // remember last x value requested
   static size_t k = 0;           // and which interval we were in

   if( xr < xlast )
      k = 0;                   // gone back to start, (or somewhere to the left)
   xlast = xr;
   while( (x[k] <= xr) && (k + 1 < n) )
      k++;
   wxASSERT( k > 0 );
   k--;
   h = x[k+1] - x[k];
   a = ( x[k+1] - xr )/h;
   b = (xr - x[k])/h;
   return( a*y[k]+b*y[k+1]+((a*a*a-a)*y2[k]+(b*b*b-b)*y2[k+1])*h*h/6.);
}

void EffectEqualization::OnErase( wxEvent& )
{
}

void EffectEqualization::OnSize(wxSizeEvent & event)
{
   mUIParent->Layout();
   event.Skip();
}

void EffectEqualization::OnSlider(wxCommandEvent & event)
{
   wxSlider *s = (wxSlider *)event.GetEventObject();
   for (size_t i = 0; i < mBandsInUse; i++)
   {
      if( s == mSliders[i])
      {
         int posn = mSliders[i]->GetValue();
         if( wxGetKeyState(WXK_SHIFT) )
         {
            if( posn > mSlidersOld[i] )
               mEQVals[i] += (float).1;
            else
               if( posn < mSlidersOld[i] )
                  mEQVals[i] -= .1f;
         }
         else
            mEQVals[i] += (posn - mSlidersOld[i]);
         if( mEQVals[i] > 20. )
            mEQVals[i] = 20.;
         if( mEQVals[i] < -20. )
            mEQVals[i] = -20.;
         int newPosn = (int)mEQVals[i];
         mSliders[i]->SetValue( newPosn );
         mSlidersOld[i] = newPosn;
         wxString tip;
         if( kThirdOct[i] < 1000.)
            tip.Printf( wxT("%dHz\n%.1fdB"), (int)kThirdOct[i], mEQVals[i] );
         else
            tip.Printf( wxT("%gkHz\n%.1fdB"), kThirdOct[i]/1000., mEQVals[i] );
         s->SetToolTip(tip);
         break;
      }
   }
   GraphicEQ(mLogEnvelope.get());
   EnvelopeUpdated();
}

void EffectEqualization::OnInterp(wxCommandEvent & WXUNUSED(event))
{
   bool bIsGraphic = !mDrawMode;
   if (bIsGraphic)
   {
      GraphicEQ(mLogEnvelope.get());
      EnvelopeUpdated();
   }
   mInterp = mInterpChoice->GetSelection();
}

void EffectEqualization::OnDrawMode(wxCommandEvent & WXUNUSED(event))
{
   mDrawMode = true;
   UpdateDraw();
}

void EffectEqualization::OnGraphicMode(wxCommandEvent & WXUNUSED(event))
{
   mDrawMode = false;
   UpdateGraphic();
}

void EffectEqualization::OnSliderM(wxCommandEvent & WXUNUSED(event))
{
   size_t m = 2 * mMSlider->GetValue() + 1;
   // Must be odd
   wxASSERT( (m & 1) == 1 );

   if (m != mM) {
      mM = m;
      wxString tip;
      tip.Printf(wxT("%d"), (int)mM);
      mMText->SetLabel(tip);
      mMText->SetName(mMText->GetLabel()); // fix for bug 577 (NVDA/Narrator screen readers do not read static text in dialogs)
      mMSlider->SetToolTip(tip);

      ForceRecalc();
   }
}

void EffectEqualization::OnSliderDBMIN(wxCommandEvent & WXUNUSED(event))
{
   float dB = mdBMinSlider->GetValue();
   if (dB != mdBMin) {
      mdBMin = dB;
      wxString tip;
      tip.Printf(_("%d dB"), (int)mdBMin);
      mdBMinSlider->SetToolTip(tip);
      UpdateRuler();
   }
}

void EffectEqualization::OnSliderDBMAX(wxCommandEvent & WXUNUSED(event))
{
   float dB = mdBMaxSlider->GetValue();
   if (dB != mdBMax) {
      mdBMax = dB;
      wxString tip;
      tip.Printf(_("%d dB"), (int)mdBMax);
      mdBMaxSlider->SetToolTip(tip);
      UpdateRuler();
   }
}

//
// New curve was selected
//
void EffectEqualization::OnCurve(wxCommandEvent & WXUNUSED(event))
{
   // Select NEW curve
   wxASSERT( mCurve != NULL );
   setCurve( mCurve->GetCurrentSelection() );
   if( !mDrawMode )
      UpdateGraphic();
}

//
// User wants to modify the list in some way
//
void EffectEqualization::OnManage(wxCommandEvent & WXUNUSED(event))
{
   EditCurvesDialog d(mUIParent, this, mCurve->GetSelection());
   d.ShowModal();

   // Reload the curve names
   UpdateCurves();

   // Allow control to resize
   mUIParent->Layout();
}

void EffectEqualization::OnClear(wxCommandEvent & WXUNUSED(event))
{
   Flatten();
}

void EffectEqualization::OnInvert(wxCommandEvent & WXUNUSED(event)) // Inverts any curve
{
   if(!mDrawMode)   // Graphic (Slider) mode. Invert the sliders.
   {
      for (size_t i = 0; i < mBandsInUse; i++)
      {
         mEQVals[i] = -mEQVals[i];
         int newPosn = (int)mEQVals[i];
         mSliders[i]->SetValue( newPosn );
         mSlidersOld[i] = newPosn;

         wxString tip;
         if( kThirdOct[i] < 1000.)
            tip.Printf( wxT("%dHz\n%.1fdB"), (int)kThirdOct[i], mEQVals[i] );
         else
            tip.Printf( wxT("%gkHz\n%.1fdB"), kThirdOct[i]/1000., mEQVals[i] );
         mSliders[i]->SetToolTip(tip);
      }
      GraphicEQ(mLogEnvelope.get());
   }
   else  // Draw mode.  Invert the points.
   {
      bool lin = IsLinear(); // refers to the 'log' or 'lin' of the frequency scale, not the amplitude
      size_t numPoints; // number of points in the curve/envelope

      // determine if log or lin curve is the current one
      // and find out how many points are in the curve
      if(lin)  // lin freq scale and so envelope
      {
         numPoints = mLinEnvelope->GetNumberOfPoints();
      }
      else
      {
         numPoints = mLogEnvelope->GetNumberOfPoints();
      }

      if( numPoints == 0 )
         return;

      Doubles when{ numPoints };
      Doubles value{ numPoints };

      if(lin)
         mLinEnvelope->GetPoints( when.get(), value.get(), numPoints );
      else
         mLogEnvelope->GetPoints( when.get(), value.get(), numPoints );

      // invert the curve
      for (size_t i = 0; i < numPoints; i++)
      {
         if(lin)
            mLinEnvelope->Reassign(when[i] , -value[i]);
         else
            mLogEnvelope->Reassign(when[i] , -value[i]);
      }

      // copy it back to the other one (just in case)
      if(lin)
         EnvLinToLog();
      else
         EnvLogToLin();
   }

   // and update the display etc
   ForceRecalc();
   EnvelopeUpdated();
}

void EffectEqualization::OnGridOnOff(wxCommandEvent & WXUNUSED(event))
{
   mDrawGrid = mGridOnOff->IsChecked();
   mPanel->Refresh(false);
}

void EffectEqualization::OnLinFreq(wxCommandEvent & WXUNUSED(event))
{
   mLin = mLinFreq->IsChecked();
   if(IsLinear())  //going from log to lin freq scale
   {
      mFreqRuler->ruler.SetLog(false);
      mFreqRuler->ruler.SetRange(0, mHiFreq);
      EnvLogToLin();
      mEnvelope = mLinEnvelope.get();
      mLin = true;
   }
   else  //going from lin to log freq scale
   {
      mFreqRuler->ruler.SetLog(true);
      mFreqRuler->ruler.SetRange(mLoFreq, mHiFreq);
      EnvLinToLog();
      mEnvelope = mLogEnvelope.get();
      mLin = false;
   }
   mFreqRuler->Refresh(false);
   ForceRecalc();
}

#ifdef EXPERIMENTAL_EQ_SSE_THREADED

void EffectEqualization::OnProcessingRadio(wxCommandEvent & event)
{
   int testEvent=event.GetId();
   switch(testEvent)
   {
   case ID_DefaultMath: EffectEqualization48x::SetMathPath(MATH_FUNCTION_ORIGINAL);
      break;
   case ID_SSE: EffectEqualization48x::SetMathPath(MATH_FUNCTION_SSE);
      break;
   case ID_SSEThreaded: EffectEqualization48x::SetMathPath(MATH_FUNCTION_THREADED | MATH_FUNCTION_SSE);
      break;
   case ID_AVX: testEvent = 2;
      break;
   case ID_AVXThreaded: testEvent = 2;
      break;
   }

};

void EffectEqualization::OnBench( wxCommandEvent & event)
{
   mBench=true;
   // OnOk(event);
}

#endif

//----------------------------------------------------------------------------
// EqualizationPanel
//----------------------------------------------------------------------------

BEGIN_EVENT_TABLE(EqualizationPanel, wxPanelWrapper)
   EVT_PAINT(EqualizationPanel::OnPaint)
   EVT_MOUSE_EVENTS(EqualizationPanel::OnMouseEvent)
   EVT_MOUSE_CAPTURE_LOST(EqualizationPanel::OnCaptureLost)
   EVT_SIZE(EqualizationPanel::OnSize)
END_EVENT_TABLE()

EqualizationPanel::EqualizationPanel(
   wxWindow *parent, wxWindowID winid, EffectEqualization *effect)
:  wxPanelWrapper(parent, winid)
{
   mParent = parent;
   mEffect = effect;

   mBitmap = NULL;
   mWidth = 0;
   mHeight = 0;

   mLinEditor = std::make_unique<EnvelopeEditor>(*mEffect->mLinEnvelope, false);
   mLogEditor = std::make_unique<EnvelopeEditor>(*mEffect->mLogEnvelope, false);
   mEffect->mEnvelope->Flatten(0.);
   mEffect->mEnvelope->SetTrackLen(1.0);

   ForceRecalc();
}

EqualizationPanel::~EqualizationPanel()
{
   if(HasCapture())
      ReleaseMouse();
}

void EqualizationPanel::ForceRecalc()
{
   mRecalcRequired = true;
   Refresh(false);
}

void EqualizationPanel::Recalc()
{
   mOutr = Floats{ mEffect->mWindowSize };
   mOuti = Floats{ mEffect->mWindowSize };

   mEffect->CalcFilter();   //to calculate the actual response
   InverseRealFFT(mEffect->mWindowSize, mEffect->mFilterFuncR.get(), mEffect->mFilterFuncI.get(), mOutr.get());
}

void EqualizationPanel::OnSize(wxSizeEvent &  WXUNUSED(event))
{
   Refresh( false );
}

#include "../TrackPanelDrawingContext.h"
void EqualizationPanel::OnPaint(wxPaintEvent &  WXUNUSED(event))
{
   wxPaintDC dc(this);
   if(mRecalcRequired) {
      Recalc();
      mRecalcRequired = false;
   }
   int width, height;
   GetSize(&width, &height);

   if (!mBitmap || mWidth!=width || mHeight!=height)
   {
      mWidth = width;
      mHeight = height;
      mBitmap = std::make_unique<wxBitmap>(mWidth, mHeight,24);
   }

   wxBrush bkgndBrush(wxSystemSettings::GetColour(wxSYS_COLOUR_3DFACE));

   wxMemoryDC memDC;
   memDC.SelectObject(*mBitmap);

   wxRect bkgndRect;
   bkgndRect.x = 0;
   bkgndRect.y = 0;
   bkgndRect.width = mWidth;
   bkgndRect.height = mHeight;
   memDC.SetBrush(bkgndBrush);
   memDC.SetPen(*wxTRANSPARENT_PEN);
   memDC.DrawRectangle(bkgndRect);

   bkgndRect.y = mHeight;
   memDC.DrawRectangle(bkgndRect);

   wxRect border;
   border.x = 0;
   border.y = 0;
   border.width = mWidth;
   border.height = mHeight;

   memDC.SetBrush(*wxWHITE_BRUSH);
   memDC.SetPen(*wxBLACK_PEN);
   memDC.DrawRectangle(border);

   mEnvRect = border;
   mEnvRect.Deflate(PANELBORDER, PANELBORDER);

   // Pure blue x-axis line
   memDC.SetPen(wxPen(theTheme.Colour( clrGraphLines ), 1, wxPENSTYLE_SOLID));
   int center = (int) (mEnvRect.height * mEffect->mdBMax/(mEffect->mdBMax-mEffect->mdBMin) + .5);
   AColor::Line(memDC,
      mEnvRect.GetLeft(), mEnvRect.y + center,
      mEnvRect.GetRight(), mEnvRect.y + center);

   // Draw the grid, if asked for.  Do it now so it's underneath the main plots.
   if( mEffect->mDrawGrid )
   {
      mEffect->mFreqRuler->ruler.DrawGrid(memDC, mEnvRect.height, true, true, PANELBORDER, PANELBORDER);
      mEffect->mdBRuler->ruler.DrawGrid(memDC, mEnvRect.width, true, true, PANELBORDER, PANELBORDER);
   }

   // Med-blue envelope line
   memDC.SetPen(wxPen(theTheme.Colour(clrGraphLines), 3, wxPENSTYLE_SOLID));

   // Draw envelope
   int x, y, xlast = 0, ylast = 0;
   {
      Doubles values{ size_t(mEnvRect.width) };
      mEffect->mEnvelope->GetValues(values.get(), mEnvRect.width, 0.0, 1.0 / mEnvRect.width);
      bool off = false, off1 = false;
      for (int i = 0; i < mEnvRect.width; i++)
      {
         x = mEnvRect.x + i;
         y = lrint(mEnvRect.height*((mEffect->mdBMax - values[i]) / (mEffect->mdBMax - mEffect->mdBMin)) + .25); //needs more optimising, along with'what you get'?
         if (y >= mEnvRect.height)
         {
            y = mEnvRect.height - 1;
            off = true;
         }
         else
         {
            off = false;
            off1 = false;
         }
         if ((i != 0) & (!off1))
         {
            AColor::Line(memDC, xlast, ylast,
               x, mEnvRect.y + y);
         }
         off1 = off;
         xlast = x;
         ylast = mEnvRect.y + y;
      }
   }

   //Now draw the actual response that you will get.
   //mFilterFunc has a linear scale, window has a log one so we have to fiddle about
   memDC.SetPen(wxPen(theTheme.Colour( clrResponseLines ), 1, wxPENSTYLE_SOLID));
   double scale = (double)mEnvRect.height/(mEffect->mdBMax-mEffect->mdBMin);   //pixels per dB
   double yF;   //gain at this freq
   double delta = mEffect->mHiFreq / (((double)mEffect->mWindowSize / 2.));   //size of each freq bin

   bool lin = mEffect->IsLinear();   // log or lin scale?

   double loLog = log10(mEffect->mLoFreq);
   double step = lin ? mEffect->mHiFreq : (log10(mEffect->mHiFreq) - loLog);
   step /= ((double)mEnvRect.width-1.);
   double freq;   //actual freq corresponding to x position
   int halfM = (mEffect->mM - 1) / 2;
   int n;   //index to mFreqFunc
   for(int i=0; i<mEnvRect.width; i++)
   {
      x = mEnvRect.x + i;
      freq = lin ? step*i : pow(10., loLog + i*step);   //Hz
      if( ( lin ? step : (pow(10., loLog + (i+1)*step)-freq) ) < delta)
      {   //not enough resolution in FFT
         // set up for calculating cos using recurrence - faster than calculating it directly each time
         double theta = M_PI*freq/mEffect->mHiFreq;   //radians, normalized
         double wtemp = sin(0.5 * theta);
         double wpr = -2.0 * wtemp * wtemp;
         double wpi = -1.0 * sin(theta);
         double wr = cos(theta*halfM);
         double wi = sin(theta*halfM);

         yF = 0.;
         for(int j=0;j<halfM;j++)
         {
            yF += 2. * mOutr[j] * wr;  // This works for me, compared to the previous version.  Compare wr to cos(theta*(halfM-j)).  Works for me.  Keep everything as doubles though.
            // do recurrence
            wr = (wtemp = wr) * wpr - wi * wpi + wr;
            wi = wi * wpr + wtemp * wpi + wi;
         }
         yF += mOutr[halfM];
         yF = fabs(yF);
         if(yF!=0.)
            yF = LINEAR_TO_DB(yF);
         else
            yF = mEffect->mdBMin;
      }
      else
      {   //use FFT, it has enough resolution
         n = (int)(freq/delta + .5);
         if(pow(mEffect->mFilterFuncR[n],2)+pow(mEffect->mFilterFuncI[n],2)!=0.)
            yF = 10.0*log10(pow(mEffect->mFilterFuncR[n],2)+pow(mEffect->mFilterFuncI[n],2));   //10 here, a power
         else
            yF = mEffect->mdBMin;
      }
      if(yF < mEffect->mdBMin)
         yF = mEffect->mdBMin;
      yF = center-scale*yF;
      if(yF>mEnvRect.height)
         yF = mEnvRect.height - 1;
      if(yF<0.)
         yF=0.;
      y = (int)(yF+.5);

      if (i != 0)
      {
         AColor::Line(memDC, xlast, ylast, x, mEnvRect.y + y);
      }
      xlast = x;
      ylast = mEnvRect.y + y;
   }

   memDC.SetPen(*wxBLACK_PEN);
   if( mEffect->mDrawMode )
   {
      ZoomInfo zoomInfo( 0.0, mEnvRect.width-1 );

      // Back pointer to TrackPanel won't be needed in the one drawing
      // function we use here
      TrackArtist artist( nullptr );

      artist.pZoomInfo = &zoomInfo;
      TrackPanelDrawingContext context{ memDC, {}, {}, &artist  };
      EnvelopeEditor::DrawPoints( *mEffect->mEnvelope,
         context, mEnvRect, false, 0.0,
      mEffect->mdBMin, mEffect->mdBMax, false);
   }

   dc.Blit(0, 0, mWidth, mHeight, &memDC, 0, 0, wxCOPY, FALSE);
}

void EqualizationPanel::OnMouseEvent(wxMouseEvent & event)
{
   if (!mEffect->mDrawMode)
   {
      return;
   }

   if (event.ButtonDown() && !HasCapture())
   {
      CaptureMouse();
   }

   auto &pEditor = (mEffect->mLin ? mLinEditor : mLogEditor);
   if (pEditor->MouseEvent(event, mEnvRect, ZoomInfo(0.0, mEnvRect.width),
      false, 0.0,
      mEffect->mdBMin, mEffect->mdBMax))
   {
      mEffect->EnvelopeUpdated();
      ForceRecalc();
   }

   if (event.ButtonUp() && HasCapture())
   {
      ReleaseMouse();
   }
}

void EqualizationPanel::OnCaptureLost(wxMouseCaptureLostEvent & WXUNUSED(event))
{
   if (HasCapture())
   {
      ReleaseMouse();
   }
}

//----------------------------------------------------------------------------
// EditCurvesDialog
//----------------------------------------------------------------------------
// Note that the 'modified' curve used to be called 'custom' but is now called 'unnamed'
// Some things that deal with 'unnamed' curves still use, for example, 'mCustomBackup' as variable names.
/// Constructor

BEGIN_EVENT_TABLE(EditCurvesDialog, wxDialogWrapper)
   EVT_BUTTON(UpButtonID, EditCurvesDialog::OnUp)
   EVT_BUTTON(DownButtonID, EditCurvesDialog::OnDown)
   EVT_BUTTON(RenameButtonID, EditCurvesDialog::OnRename)
   EVT_BUTTON(DeleteButtonID, EditCurvesDialog::OnDelete)
   EVT_BUTTON(ImportButtonID, EditCurvesDialog::OnImport)
   EVT_BUTTON(ExportButtonID, EditCurvesDialog::OnExport)
   EVT_BUTTON(LibraryButtonID, EditCurvesDialog::OnLibrary)
   EVT_BUTTON(DefaultsButtonID, EditCurvesDialog::OnDefaults)
   EVT_BUTTON(wxID_OK, EditCurvesDialog::OnOK)
   EVT_LIST_ITEM_SELECTED(CurvesListID,
                          EditCurvesDialog::OnListSelectionChange)
   EVT_LIST_ITEM_DESELECTED(CurvesListID,
                          EditCurvesDialog::OnListSelectionChange)
END_EVENT_TABLE()

EditCurvesDialog::EditCurvesDialog(wxWindow * parent, EffectEqualization * effect, int position):
wxDialogWrapper(parent, wxID_ANY, XO("Manage Curves List"),
         wxDefaultPosition, wxDefaultSize,
         wxDEFAULT_DIALOG_STYLE | wxRESIZE_BORDER)
{
   SetLabel(XO("Manage Curves"));         // Provide visual label
   SetName(XO("Manage Curves List"));     // Provide audible label
   mParent = parent;
   mEffect = effect;
   mPosition = position;
   // make a copy of mEffect->mCurves here to muck about with.
   mEditCurves.clear();
   for (unsigned int i = 0; i < mEffect->mCurves.size(); i++)
   {
      mEditCurves.push_back(mEffect->mCurves[i].Name);
      mEditCurves[i].points = mEffect->mCurves[i].points;
   }

   Populate();
   SetMinSize(GetSize());
}

EditCurvesDialog::~EditCurvesDialog()
{
}

/// Creates the dialog and its contents.
void EditCurvesDialog::Populate()
{
   //------------------------- Main section --------------------
   ShuttleGui S(this, eIsCreating);
   PopulateOrExchange(S);
   // ----------------------- End of main section --------------
}

/// Defines the dialog and does data exchange with it.
void EditCurvesDialog::PopulateOrExchange(ShuttleGui & S)
{
   S.StartHorizontalLay(wxEXPAND);
   {
      S.StartStatic(XO("&Curves"), 1);
      {
         mList = S.Id(CurvesListID)
            .Style(wxSUNKEN_BORDER | wxLC_REPORT | wxLC_HRULES | wxLC_VRULES )
            .AddListControlReportMode({
               { XO("Curve Name"), wxLIST_FORMAT_RIGHT }
            });
      }
      S.EndStatic();
      S.StartVerticalLay(0);
      {
         S.Id(UpButtonID).AddButton(XXO("Move &Up"), wxALIGN_LEFT);
         S.Id(DownButtonID).AddButton(XXO("Move &Down"), wxALIGN_LEFT);
         S.Id(RenameButtonID).AddButton(XXO("&Rename..."), wxALIGN_LEFT);
         S.Id(DeleteButtonID).AddButton(XXO("D&elete..."), wxALIGN_LEFT);
         S.Id(ImportButtonID).AddButton(XXO("I&mport..."), wxALIGN_LEFT);
         S.Id(ExportButtonID).AddButton(XXO("E&xport..."), wxALIGN_LEFT);
         S.Id(LibraryButtonID).AddButton(XXO("&Get More..."), wxALIGN_LEFT);
         S.Id(DefaultsButtonID).AddButton(XXO("De&faults"), wxALIGN_LEFT);
      }
      S.EndVerticalLay();
   }
   S.EndHorizontalLay();
   S.AddStandardButtons();
   S.StartStatic(XO("Help"));
   S.AddConstTextBox( {}, XO("Rename 'unnamed' to save a new entry.\n'OK' saves all changes, 'Cancel' doesn't."));
   S.EndStatic();
   PopulateList(mPosition);
   Fit();

   return;
}

void EditCurvesDialog::PopulateList(int position)
{
   mList->DeleteAllItems();
   for (unsigned int i = 0; i < mEditCurves.size(); i++)
      mList->InsertItem(i, mEditCurves[i].Name);
   mList->SetColumnWidth(0, wxLIST_AUTOSIZE);
   int curvesWidth = mList->GetColumnWidth(0);
   mList->SetColumnWidth(0, wxLIST_AUTOSIZE_USEHEADER);
   int headerWidth = mList->GetColumnWidth(0);
   mList->SetColumnWidth(0, wxMax(headerWidth, curvesWidth));
   // use 'position' to set focus
   mList->EnsureVisible(position);
   mList->SetItemState(position, wxLIST_STATE_SELECTED|wxLIST_STATE_FOCUSED, wxLIST_STATE_SELECTED|wxLIST_STATE_FOCUSED);
}

void EditCurvesDialog::OnUp(wxCommandEvent & WXUNUSED(event))
{
   long item = mList->GetNextItem(-1, wxLIST_NEXT_ALL, wxLIST_STATE_SELECTED);
   if ( item == -1 )
      return;  // no items selected
   if( item == 0 )
      item = mList->GetNextItem(item, wxLIST_NEXT_ALL, wxLIST_STATE_SELECTED); // top item selected, can't move up
   int state;
   while( item != -1 )
   {
      if ( item == mList->GetItemCount()-1)
      {  // 'unnamed' always stays at the bottom
         mEffect->Effect::MessageBox(
            XO("'unnamed' always stays at the bottom of the list"),
            Effect::DefaultMessageBoxStyle,
            XO("'unnamed' is special") );   // these could get tedious!
         return;
      }
      state = mList->GetItemState(item-1, wxLIST_STATE_SELECTED);
      if ( state != wxLIST_STATE_SELECTED )
      { // swap this with one above but only if it isn't selected
         EQCurve temp(wxT("temp"));
         temp.Name = mEditCurves[item].Name;
         temp.points = mEditCurves[item].points;
         mEditCurves[item].Name = mEditCurves[item-1].Name;
         mEditCurves[item].points = mEditCurves[item-1].points;
         mEditCurves[item-1].Name = temp.Name;
         mEditCurves[item-1].points = temp.points;
         wxString sTemp = mList->GetItemText(item);
         mList->SetItem(item, 0, mList->GetItemText(item-1));
         mList->SetItem(item-1, 0, sTemp);
         mList->SetItemState(item, 0, wxLIST_STATE_SELECTED);
         mList->SetItemState(item-1, wxLIST_STATE_SELECTED, wxLIST_STATE_SELECTED);
      }
      item = mList->GetNextItem(item, wxLIST_NEXT_ALL, wxLIST_STATE_SELECTED);
   }
}

void EditCurvesDialog::OnDown(wxCommandEvent & WXUNUSED(event))
{  // looks harder than OnUp as we need to seek backwards up the list, hence GetPreviousItem
   long item = GetPreviousItem(mList->GetItemCount());
   if( item == -1 )
      return;  // nothing selected
   int state;
   while( item != -1 )
   {
      if( (item != mList->GetItemCount()-1) && (item != mList->GetItemCount()-2) )
      {  // can't move 'unnamed' down, or the one above it
         state = mList->GetItemState(item+1, wxLIST_STATE_SELECTED);
         if ( state != wxLIST_STATE_SELECTED )
         { // swap this with one below but only if it isn't selected
            EQCurve temp(wxT("temp"));
            temp.Name = mEditCurves[item].Name;
            temp.points = mEditCurves[item].points;
            mEditCurves[item].Name = mEditCurves[item+1].Name;
            mEditCurves[item].points = mEditCurves[item+1].points;
            mEditCurves[item+1].Name = temp.Name;
            mEditCurves[item+1].points = temp.points;
            wxString sTemp = mList->GetItemText(item);
            mList->SetItem(item, 0, mList->GetItemText(item+1));
            mList->SetItem(item+1, 0, sTemp);
            mList->SetItemState(item, 0, wxLIST_STATE_SELECTED);
            mList->SetItemState(item+1, wxLIST_STATE_SELECTED, wxLIST_STATE_SELECTED);
         }
      }
      item = GetPreviousItem(item);
   }
}

long EditCurvesDialog::GetPreviousItem(long item)  // wx doesn't have this
{
   long lastItem = -1;
   long itemTemp = mList->GetNextItem(-1, wxLIST_NEXT_ALL,
      wxLIST_STATE_SELECTED);
   while( (itemTemp != -1) && (itemTemp < item) )
   {
      lastItem = itemTemp;
      itemTemp = mList->GetNextItem(itemTemp, wxLIST_NEXT_ALL, wxLIST_STATE_SELECTED);
   }
   return lastItem;
}

// Rename curve/curves
void EditCurvesDialog::OnRename(wxCommandEvent & WXUNUSED(event))
{
   wxString name;
   int numCurves = mEditCurves.size();
   int curve = 0;

   // Setup list of characters that aren't allowed
   wxArrayStringEx exclude{
      wxT("<") ,
      wxT(">") ,
      wxT("'") ,
      wxT("\"") ,
   };

   // Get the first one to be renamed
   long item = mList->GetNextItem(-1, wxLIST_NEXT_ALL, wxLIST_STATE_SELECTED);
   long firstItem = item;  // for reselection with PopulateList
   while(item >= 0)
   {
      // Prompt the user until a valid name is enter or cancelled
      bool overwrite = false;
      bool bad = true;
      while( bad )   // Check for an unacceptable duplicate
      {   // Show the dialog and bail if the user cancels
         bad = false;
         // build the dialog
         AudacityTextEntryDialog dlg( this,
            XO("Rename '%s' to...").Format( mEditCurves[ item ].Name ),
            XO("Rename...") );
         dlg.SetTextValidator( wxFILTER_EXCLUDE_CHAR_LIST );
         dlg.SetName(
            wxString::Format( _("Rename '%s'"), mEditCurves[ item ].Name ) );
         wxTextValidator *tv = dlg.GetTextValidator();
         tv->SetExcludes( exclude );   // Tell the validator about excluded chars
         if( dlg.ShowModal() == wxID_CANCEL )
         {
            bad = true;
            break;
         }

         // Extract the name from the dialog
         name = dlg.GetValue();

         // Search list of curves for a duplicate name
         for( curve = 0; curve < numCurves; curve++ )
         {
            wxString temp = mEditCurves[ curve ].Name;
            if( name ==  mEditCurves[ curve ].Name ) // case sensitive
            {
               bad = true;
               if( curve == item )  // trying to rename a curve with the same name
               {
                  mEffect->Effect::MessageBox(
                     XO("Name is the same as the original one"),
                     wxOK,
                     XO("Same name") );
                  break;
               }
               int answer = mEffect->Effect::MessageBox(
                  XO("Overwrite existing curve '%s'?").Format( name ),
                  wxYES_NO,
                  XO("Curve exists") );
               if (answer == wxYES)
               {
                  bad = false;
                  overwrite = true; // we are going to overwrite the one with this name
                  break;
               }
            }
         }
         if( name.empty() || name == wxT("unnamed") )
            bad = true;
      }

      // if bad, we cancelled the rename dialog, so nothing to do.
      if( bad == true )
         ;
      else if(overwrite){
         // Overwrite another curve.
         // JKC: because 'overwrite' is true, 'curve' is the number of the curve that
         // we are about to overwrite.
         mEditCurves[ curve ].Name = name;
         mEditCurves[ curve ].points = mEditCurves[ item ].points;
         // if renaming the unnamed item, then select it,
         // otherwise get rid of the item we've renamed.
         if( item == (numCurves-1) )
            mList->SetItem(curve, 0, name);
         else
         {
            mEditCurves.erase( mEditCurves.begin() + item );
            numCurves--;
         }
      }
      else if( item == (numCurves-1) ) // renaming 'unnamed'
      {  // Create a NEW entry
         mEditCurves.push_back( EQCurve( wxT("unnamed") ) );
         // Copy over the points
         mEditCurves[ numCurves ].points = mEditCurves[ numCurves - 1 ].points;
         // Give the original unnamed entry the NEW name
         mEditCurves[ numCurves - 1 ].Name = name;
         numCurves++;
      }
      else  // just rename (the 'normal' case)
      {
         mEditCurves[ item ].Name = name;
         mList->SetItem(item, 0, name);
      }
      // get next selected item
      item = mList->GetNextItem(item, wxLIST_NEXT_ALL, wxLIST_STATE_SELECTED);
   }

   PopulateList(firstItem);  // Note: only saved to file when you OK out of the dialog
   return;
}

// Delete curve/curves
void EditCurvesDialog::OnDelete(wxCommandEvent & WXUNUSED(event))
{
   // We could count them here
   // And then put in a 'Delete N items?' prompt.

#if 0 // 'one at a time' prompt code
   // Get the first one to be deleted
   long item = mList->GetNextItem(-1, wxLIST_NEXT_ALL, wxLIST_STATE_SELECTED);
   // Take care, mList and mEditCurves will get out of sync as curves are deleted
   int deleted = 0;
   long highlight = -1;

   while(item >= 0)
   {
      if(item == mList->GetItemCount()-1)   //unnamed
      {
         mEffect->Effect::MessageBox(
            XO("You cannot delete the 'unnamed' curve."),
            wxOK | wxCENTRE,
            XO("Can't delete 'unnamed'") );
      }
      else
      {
         // Create the prompt
         auto quest = XO("Delete '%s'?")
            .Format(mEditCurves[ item-deleted ].Name));

         // Ask for confirmation before removal
         int ans = mEffect->Effect::MessageBox(
            quest,
            wxYES_NO | wxCENTRE,
            XO("Confirm Deletion") );
         if( ans == wxYES )
         {  // Remove the curve from the array
            mEditCurves.RemoveAt( item-deleted );
            deleted++;
         }
         else
            highlight = item-deleted;  // if user presses 'No', select that curve
      }
      // get next selected item
      item = mList->GetNextItem(item, wxLIST_NEXT_ALL, wxLIST_STATE_SELECTED);
   }

   if(highlight == -1)
      PopulateList(mEditCurves.size()-1);   // set 'unnamed' as the selected curve
   else
      PopulateList(highlight);   // user said 'No' to deletion
#else // 'DELETE all N' code
   int count = mList->GetSelectedItemCount();
   long item = mList->GetNextItem(-1, wxLIST_NEXT_ALL, wxLIST_STATE_SELECTED);
   // Create the prompt
   TranslatableString quest;
   if( count > 1 )
      quest = XO("Delete %d items?").Format( count );
   else
      if( count == 1 )
         quest = XO("Delete '%s'?").Format( mEditCurves[ item ].Name );
      else
         return;
   // Ask for confirmation before removal
   int ans = mEffect->Effect::MessageBox(
      quest,
      wxYES_NO | wxCENTRE,
      XO("Confirm Deletion") );
   if( ans == wxYES )
   {  // Remove the curve(s) from the array
      // Take care, mList and mEditCurves will get out of sync as curves are deleted
      int deleted = 0;
      while(item >= 0)
      {
         // TODO: Migrate to the standard "Manage" dialog.
         if(item == mList->GetItemCount()-1)   //unnamed
         {
            mEffect->Effect::MessageBox(
               XO("You cannot delete the 'unnamed' curve, it is special."),
               Effect::DefaultMessageBoxStyle,
               XO("Can't delete 'unnamed'") );
         }
         else
         {
            mEditCurves.erase( mEditCurves.begin() + item - deleted );
            deleted++;
         }
         item = mList->GetNextItem(item, wxLIST_NEXT_ALL, wxLIST_STATE_SELECTED);
      }
      PopulateList(mEditCurves.size() - 1);   // set 'unnamed' as the selected curve
   }
#endif
}

static const FileNames::FileTypes &XMLtypes()
{
   static const FileNames::FileTypes results{
      FileNames::XMLFiles
   };
   return results;
}

void EditCurvesDialog::OnImport( wxCommandEvent & WXUNUSED(event))
{
   FileDialogWrapper filePicker(
      this,
      XO("Choose an EQ curve file"), FileNames::DataDir(), wxT(""),
      XMLtypes() );
   wxString fileName;
   if( filePicker.ShowModal() == wxID_CANCEL)
      return;
   else
      fileName = filePicker.GetPath();
   // Use EqualizationDialog::LoadCurves to read into (temporary) mEditCurves
   // This may not be the best OOP way of doing it, but I don't know better (MJS)
   EQCurveArray temp;
   temp = mEffect->mCurves;   // temp copy of the main dialog curves
   mEffect->mCurves = mEditCurves;  // copy EditCurvesDialog to main interface
   mEffect->LoadCurves(fileName, true);   // use main interface to load imported curves
   mEditCurves = mEffect->mCurves;  // copy back to this interface
   mEffect->mCurves = temp;   // and reset the main interface how it was
   PopulateList(0);  // update the EditCurvesDialog dialog
   return;
}

void EditCurvesDialog::OnExport( wxCommandEvent & WXUNUSED(event))
{
   FileDialogWrapper filePicker(this, XO("Export EQ curves as..."),
      FileNames::DataDir(), wxT(""),
      XMLtypes(),
      wxFD_SAVE | wxFD_OVERWRITE_PROMPT | wxRESIZE_BORDER); // wxFD_CHANGE_DIR?
   wxString fileName;
   if( filePicker.ShowModal() == wxID_CANCEL)
      return;
   else
      fileName = filePicker.GetPath();

   EQCurveArray temp;
   temp = mEffect->mCurves;   // backup the parent's curves
   EQCurveArray exportCurves;   // Copy selected curves to export
   exportCurves.clear();
   long item = mList->GetNextItem(-1, wxLIST_NEXT_ALL, wxLIST_STATE_SELECTED);
   int i=0;
   while(item >= 0)
   {
      if(item != mList->GetItemCount()-1)   // not 'unnamed'
      {
         exportCurves.push_back(mEditCurves[item].Name);
         exportCurves[i].points = mEditCurves[item].points;
         i++;
      }
      else
         mEffect->Effect::MessageBox(
            XO("You cannot export 'unnamed' curve, it is special."),
            Effect::DefaultMessageBoxStyle,
            XO("Cannot Export 'unnamed'") );
      // get next selected item
      item = mList->GetNextItem(item, wxLIST_NEXT_ALL, wxLIST_STATE_SELECTED);
   }
   if(i>0)
   {
      mEffect->mCurves = exportCurves;
      mEffect->SaveCurves(fileName);
      mEffect->mCurves = temp;
      auto message = XO("%d curves exported to %s").Format( i, fileName );
      mEffect->Effect::MessageBox(
         message,
         Effect::DefaultMessageBoxStyle,
         XO("Curves exported") );
   }
   else
      mEffect->Effect::MessageBox(
         XO("No curves exported"),
         Effect::DefaultMessageBoxStyle,
         XO("No curves exported") );
}

void EditCurvesDialog::OnLibrary( wxCommandEvent & WXUNUSED(event))
{
   // full path to wiki.
   wxLaunchDefaultBrowser(wxT("https://wiki.audacityteam.org/wiki/EQCurvesDownload"));
}

void EditCurvesDialog::OnDefaults( wxCommandEvent & WXUNUSED(event))
{
   EQCurveArray temp;
   temp = mEffect->mCurves;
   // we expect this to fail in LoadCurves (due to a lack of path) and handle that there
   mEffect->LoadCurves( wxT("EQDefaultCurves.xml") );
   mEditCurves = mEffect->mCurves;
   mEffect->mCurves = temp;
   PopulateList(0);  // update the EditCurvesDialog dialog
}

void EditCurvesDialog::OnOK(wxCommandEvent & WXUNUSED(event))
{
   // Make a backup of the current curves
   wxString backupPlace = wxFileName( FileNames::DataDir(), wxT("EQBackup.xml") ).GetFullPath();
   mEffect->SaveCurves(backupPlace);
   // Load back into the main dialog
   mEffect->mCurves.clear();
   for (unsigned int i = 0; i < mEditCurves.size(); i++)
   {
      mEffect->mCurves.push_back(mEditCurves[i].Name);
      mEffect->mCurves[i].points = mEditCurves[i].points;
   }
   mEffect->SaveCurves();
   mEffect->LoadCurves();
//   mEffect->CreateChoice();
   wxGetTopLevelParent(mEffect->mUIParent)->Layout();
//   mEffect->mUIParent->Layout();

   // Select something sensible
   long item = mList->GetNextItem(-1,
      wxLIST_NEXT_ALL,
      wxLIST_STATE_SELECTED);
   if (item == -1)
      item = mList->GetItemCount()-1;   // nothing selected, default to 'unnamed'
   mEffect->setCurve(item);
   EndModal(true);
}

void EditCurvesDialog::OnListSelectionChange( wxListEvent & )
{
   const bool enable = mList->GetSelectedItemCount() > 0;
   static const int ids[] = {
      UpButtonID,
      DownButtonID,
      RenameButtonID,
      DeleteButtonID,
   };
   for (auto id : ids)
      FindWindowById(id, this)->Enable(enable);
}

