/*
  GnuplotGen  -  building blocks for simplified data visualisation via Gnuplot

  Copyright (C)         Lumiera.org
    2024,               Hermann Vosseler <Ichthyostega@web.de>

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

  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with this program; if not, write to the Free Software
  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

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


/** @file gnuplot-gen.cpp
 ** Definition of building blocks and preconfigured styles for Gnuplot scripts.
 ** The purpose of this setup is to generate visualisations of measurement data easily.
 ** A collection of plotting definitions, together with uniform styles is maintained
 ** within this translation unit, exposing a simple interface where the user only needs
 ** to supply the actual data to be plotted. Intentionally, this collection is started
 ** without much structure or preconceptions and written in a way to encourage adding
 ** more use-cases by copy-and-paste. Following this pragmatic approach, generalisations
 ** and common schemes will emerge eventually.
 ** @todo WIP-WIP 4/2024 first usage as part of Scheduler stress testing.
 */


#include "lib/text-template.hpp"
#include "lib/text-template-gen-node-binding.hpp"
#include "lib/gnuplot-gen.hpp"
#include "lib/format-util.hpp"

#include <string>

using std::string;

using util::join;
using lib::diff::MakeRec;


namespace lib {
namespace gnuplot_gen {
  
  namespace { // Template and defaults definitions for diagram generation
    
    
    const string GNUPLOT_CommonStyleDef = R"~(#
#---common-styles-for-plots-from-Lumiera----
set style line 1 linetype  1 linewidth 2 linecolor rgb '#240CC3'
set style line 2 linetype  3 linewidth 2 linecolor rgb '#1149D6'
set style line 3 linetype  2 linewidth 2 linecolor rgb '#0B7FCC'
set style line 4 linetype  6 linewidth 2 linecolor rgb '#37999D'
set style line 5 linetype  7 linewidth 2 linecolor rgb '#248269'
set style line 6 linetype 13 linewidth 2 linecolor rgb '#00C443'
set style line 7 linetype 12 linewidth 2 linecolor rgb '#B86E1C'
set style line 8 linetype  5 linewidth 2 linecolor rgb '#762C14'
set style line 9 linetype  4 linewidth 2 linecolor rgb '#AA0519'

set style line 10 linetype 1 linewidth 1 linecolor rgb '#303030'
set style line 11 linetype 0 linewidth 1 linecolor rgb '#A0A0A0' dashtype 3
#---(End)styles-----------------------------
)~";
    
    const string GNUPLOT_AxisGridSetup = R"~(#
#---axis-and-grid-setup---------------------
unset border
set tics nomirror
set grid back linestyle 11

set arrow 10 from graph 0,0 to graph 1.04,0 size screen 0.025,15,60 filled ls 10
set arrow 11 from graph 0,0 to graph 0,1.05 size screen 0.025,15,60 filled ls 10
)~";
    
    
    const string GNUPLOT_BASIC_PLOT_DEF = R"~(#
#
#   GNUPLOT - data plot from Lumiera
#

${if Term}set term ${Term} ${
if TermSizeSpec}size ${TermSizeSpec}${endif}${
endif Term}

set datafile separator ",;"

####---------Data---------------------------
$RunData << _End_of_Data_
${CSVData}
_End_of_Data_


${CommonStyleDef}
${AxisGridSetup}

${if XLabel
}set xlabel '${XLabel}'
${else
}stats $RunData using (abscissaName=strcol(1)) every ::0::0 nooutput

set xlabel abscissaName
${end if XLabel
}${if YLabel
}set ylabel '${YLabel}'
${end if YLabel
}
set key autotitle columnheader tmargin

)~";
    
    const string GNUPLOT_SIMPLE_DATA_PLOT = R"~(#
####----------------------------------------
plot for [i=2:*] $RunData using 1:i with ${DiagramKind} linestyle i-1

)~";
    
    
    const string GNUPLOT_SCATTER_REGRESSION = R"~(#
#
#

set arrow 1 from graph 0, first 1 to graph 1, first 30 nohead ls 9

set multiplot layout 2,1
set lmargin at screen 0.12
set rmargin at screen 0.88

plot $RunData using 1:2 with points linestyle 1
unset arrow 1
unset arrow 10
unset arrow 11
set border 2+8

set yrange [0:8]
set y2range [500:2000]

unset x2label
set format x ""
set ylabel "Y1 axis"
set y2label "Y2 axis" offset -2
set y2tics
plot $RunData using 1:3 with impulses linestyle 3, \
     $RunData using 1:4 with points   linestyle 5 axes x1y2


)~";
    
    template<class IT>
    inline string
    renderCSV (IT& iter)
    {
      return join (iter, "\n");
    }
  }//(End)template and defaults definitions
  
  
  /** */
  string
  dataPlot (CSVRowIter& rowIT)
  {
    TextTemplate plot{GNUPLOT_BASIC_PLOT_DEF
                     +GNUPLOT_SIMPLE_DATA_PLOT};
    
    auto config
      = MakeRec()
          .set ("CommonStyleDef", GNUPLOT_CommonStyleDef)
          .set ("AxisGridSetup",  GNUPLOT_AxisGridSetup)
          .set ("DiagramKind",    "points")
          .set ("CSVData", renderCSV(rowIT))
        .genNode();
    
    return plot.render(config);
  }
  
}} // namespace lib::gnuplot_gen