% tkz-graph-lua.tex -- part of tkz-graph : option lua
% Copyright 2026  Alain Matthes
% SPDX-License-Identifier: LPPL-1.3c
% This work may be distributed and/or modified under the
% conditions of the LaTeX Project Public License, either version 1.3c
% of this license or (at your option) any later version.
% The latest version of this license is in
%   https://www.latex-project.org/lppl.txt
% and version 1.3c or later is part of all distributions of LaTeX
% version 2005/12/01 or later.
%
% This work has the LPPL maintenance status "maintained".
%
% The Current Maintainer of this work is Alain Matthes.
%
% Read once by \tkzgr@loadlua (tkz-graph.sty), with the option lua
% (\usepackage[lua]{tkz-graph} or \usepackage[lua]{tkz-berge}), LuaLaTeX
% only : computations on the graph drawn in the current tikzpicture
% (degrees, Dijkstra, Welsh-Powell, Euler...). Lua part : tkz-graph.lua.
% Not a package.
% the Lua file is searched as a Lua file, then as a TeX file
\def\tkzgl@nolua{\PackageError{tkz-graph}{File tkz-graph.lua not found}%
  {Install tkz-graph.lua next to tkz-graph.sty.}\endinput}
\directlua{
  local f = kpse.find_file("tkz-graph.lua", "lua")
            or kpse.find_file("tkz-graph.lua", "tex")
  if f then tkzgraph = dofile(f) end}
\directlua{if not tkzgraph then tex.sprint("\string\\tkzgl@nolua") end}
%<--------------------------------------------------------------------------->
%                     Recording of the graph in Lua
%<--------------------------------------------------------------------------->
\def\tkzgl@str#1{\luaescapestring{\detokenize\expandafter{#1}}}
\def\tkzgr@hook@reset{\directlua{tkzgraph.reset()}}
\def\tkzgr@hook@vertex#1{%
  \directlua{tkzgraph.vertex("\luaescapestring{#1}")}}
% the label, the arrow and the style may be macros that contain macros
% (\SetUpEdge) : they are expanded (protected) before being sent to Lua
\def\tkzgr@hook@edge#1#2#3#4{%
  \begingroup
  \protected@edef\tkzgl@l{#3}%
  \protected@edef\tkzgl@a{#4}%
  \ifdefined\cmdGR@edge@style
    \protected@edef\tkzgl@s{\cmdGR@edge@style}%
  \else
    \let\tkzgl@s\@empty
  \fi
  \directlua{tkzgraph.edge("\luaescapestring{#1}", "\luaescapestring{#2}",
     "\tkzgl@str{\tkzgl@l}", "\tkzgl@str{\tkzgl@a}", "\tkzgl@str{\tkzgl@s}")}%
  \endgroup}
\directlua{tkzgraph.reset()}
%<--------------------------------------------------------------------------->
%                               Texts
%<--------------------------------------------------------------------------->
\newcommand*{\tkzGraphVertexText}{Vertex}
\newcommand*{\tkzGraphDegreeText}{Degree}
\newcommand*{\tkzGraphColorText}{Color}
\newcommand*{\tkzGraphChoiceText}{Choice}
\newcommand*{\tkzGraphDoneMark}{\rule[-.2ex]{.8em}{1.6ex}}
\newcommand*{\tkzGraphColorSwatch}[1]{%
  \textcolor{#1}{\rule[-.2ex]{1.2em}{1.6ex}}\,\texttt{#1}}
% rules of the tables : booktabs if loaded
\let\tkzgl@top\hline \let\tkzgl@mid\hline \let\tkzgl@bot\hline
\AtBeginDocument{%
  \ifdefined\toprule
    \let\tkzgl@top\toprule \let\tkzgl@mid\midrule \let\tkzgl@bot\bottomrule
  \fi}
%<--------------------------------------------------------------------------->
%                         Order, size, degrees
%<--------------------------------------------------------------------------->
\newcommand*{\tkzGraphOrder}{\directlua{tkzgraph.order()}}
\newcommand*{\tkzGraphSize}{\directlua{tkzgraph.size()}}
\newcommand*{\tkzGraphDegree}[1]{%
  \directlua{tkzgraph.degree("\luaescapestring{#1}", "all")}}
\newcommand*{\tkzGraphInDegree}[1]{%
  \directlua{tkzgraph.degree("\luaescapestring{#1}", "in")}}
\newcommand*{\tkzGraphOutDegree}[1]{%
  \directlua{tkzgraph.degree("\luaescapestring{#1}", "out")}}
\newcommand*{\tkzGraphDegreeSequence}[1][, ]{%
  \directlua{tkzgraph.degree_sequence("\luaescapestring{#1}")}}
% tables : math (names in math mode), sort (degree table)
\tkzgr@boolkey{ltab}{math}
\tkzgr@boolkey{ltab}{sort}
\tkzgr@presetkeys{ltab}{math = false, sort = true}
\def\tkzgl@bool#1{\csname ifGR@#1\endcsname true\else false\fi}
\newcommand*{\tkzGraphDegreeTable}[1][]{%
  \begingroup
  \tkzgr@setkeys{ltab}{#1}%
  \directlua{tkzgraph.degree_table(\tkzgl@bool{ltab@sort},
                                   \tkzgl@bool{ltab@math})}%
  \endgroup}
%<--------------------------------------------------------------------------->
%                               Dijkstra
%<--------------------------------------------------------------------------->
% \tkzGraphDijkstra[options](A)(B) : shortest path from A to B, drawn
% again over the edges. Edges without arrow are two-way (directed : from
% the first vertex to the second). The weight of an edge is its label
% when it is a number, otherwise 1.
\tkzgr@cmdkey{dij}{color}
\tkzgr@cmdkey{dij}{lw}
\tkzgr@cmdkey{dij}{style}
\tkzgr@boolkey{dij}{draw}
\tkzgr@boolkey{dij}{directed}
\tkzgr@presetkeys{dij}{color    = red,
                       lw       = 1.6pt,
                       style    = {},
                       draw     = true,
                       directed = false}
\newcommand*{\tkzGraphPath}{}
\newcommand*{\tkzGraphPathLength}{}
\newcommand*{\tkzGraphDijkstra}[1][]{\tkzgl@dijkstra[#1]}
\def\tkzgl@dijkstra[#1](#2)(#3){%
  \begingroup
  \tkzgr@setkeys{dij}{#1}%
  \directlua{tkzgraph.dijkstra("\luaescapestring{#2}",
     "\luaescapestring{#3}", \tkzgl@bool{dij@directed})}%
  \ifGR@dij@draw
    \edef\tkzgl@opts{color = \cmdGR@dij@color, line width = \cmdGR@dij@lw,
                     \unexpanded\expandafter{\cmdGR@dij@style}}%
    \directlua{tkzgraph.draw_path("\tkzgl@str{\tkzgl@opts}")}%
  \fi
  \endgroup}
\newcommand*{\tkzGraphDijkstraTable}[1][]{%
  \begingroup
  \tkzgr@setkeys{ltab}{#1}%
  \directlua{tkzgraph.dijkstra_table(\tkzgl@bool{ltab@math})}%
  \endgroup}
%<--------------------------------------------------------------------------->
%                        Welsh-Powell coloring
%<--------------------------------------------------------------------------->
\tkzgr@cmdkey{col}{colors}
\tkzgr@boolkey{col}{draw}
\tkzgr@presetkeys{col}{colors = {red,blue,green,yellow,orange,cyan,
                                 magenta,brown,lime,pink,teal,violet},
                       draw   = true}
\newcommand*{\tkzGraphColorCount}{}
\newcommand*{\tkzGraphColoring}[1][]{%
  \begingroup
  \tkzgr@setkeys{col}{#1}%
  \directlua{tkzgraph.coloring("\luaescapestring{\cmdGR@col@colors}")}%
  \ifGR@col@draw
    \directlua{tkzgraph.draw_coloring("\luaescapestring{\string\tkzgl@class}")}%
  \fi
  \endgroup}
% one class : vertices drawn again with the color (fill, and ball color
% for the shaded styles). A label inside the vertex is written again ; a
% label outside (LabelOut) is still there and is not drawn again.
\def\tkzgl@class#1#2{%
  \begingroup
  \tikzset{VertexStyle/.append style = {fill = #1, ball color = #1}}%
  \tkzgr@setkeys{vertex}{}%
  \foreach \tkzgl@v in {#2}{%
    \ifGR@vertex@LabelOut
      \tkzgr@Vertex[Node,NoLabel]{\tkzgl@v}%
    \else
      \tkzgr@Vertex[Node]{\tkzgl@v}%
    \fi}%
  \endgroup}
\newcommand*{\tkzGraphVertexColor}[1]{%
  \directlua{tkzgraph.vertex_color("\luaescapestring{#1}")}}
\newcommand*{\tkzGraphColoringTable}[1][]{%
  \begingroup
  \tkzgr@setkeys{ltab}{#1}%
  \directlua{tkzgraph.coloring_table(\tkzgl@bool{ltab@math})}%
  \endgroup}
%<--------------------------------------------------------------------------->
%                         Connectivity, Euler
%<--------------------------------------------------------------------------->
\long\def\tkzgl@firstofthree#1#2#3{#1}
\long\def\tkzgl@secondofthree#1#2#3{#2}
\long\def\tkzgl@thirdofthree#1#2#3{#3}
\newcommand*{\tkzGraphComponents}{\directlua{tkzgraph.components()}}
\newcommand{\tkzGraphIfConnected}{\directlua{tkzgraph.if_connected()}}
\newcommand*{\tkzGraphOddVertices}[1][,]{%
  \directlua{tkzgraph.odd_vertices("\luaescapestring{#1}")}}
\newcommand*{\tkzGraphEulerType}{\directlua{tkzgraph.euler_type()}}
\newcommand{\tkzGraphIfEulerian}{\directlua{tkzgraph.if_eulerian()}}
% \tkzGraphEuler[options] : an Eulerian path or cycle (Hierholzer)
%   start    first vertex (for a path : one of the two odd vertices)
%   directed the edges go from the first vertex to the second (by
%            default : directed when all the edges have an arrow)
%   numbers  the rank of each edge is written on it (EulerNumberStyle)
%   pos      position of the numbers on the edges
\tkzgr@cmdkey{eul}{start}
\tkzgr@cmdkey{eul}{pos}
\tkzgr@boolkey{eul}{directed}
\tkzgr@boolkey{eul}{numbers}
\tkzgr@presetkeys{eul}{start    = {},
                       pos      = .5,
                       directed = false,
                       numbers  = false}
\tikzset{EulerNumberStyle/.style = {circle, draw, fill = white,
                                    inner sep = 1pt, font = \scriptsize}}
\newcommand*{\tkzGraphEulerPath}{}
\newcommand*{\tkzGraphEuler}[1][]{%
  \begingroup
  \tkzgr@setkeys{eul}{#1}%
  \directlua{tkzgraph.euler("\luaescapestring{\cmdGR@eul@start}",
                            \tkzgl@bool{eul@directed})}%
  \ifGR@eul@numbers
    \directlua{tkzgraph.draw_euler("\luaescapestring{\cmdGR@eul@pos}")}%
  \fi
  \endgroup}
%<--------------------------------------------------------------------------->
%                     Powers of the adjacency matrix
%<--------------------------------------------------------------------------->
% \tkzGraphMatrixPower[directed,order={A,B,...}]{k}  M^k
% \tkzGraphWalks[directed]{k}(A)(B)  number of walks of length k
% same rules as \tkzAdjacencyMatrix
\tkzgr@boolkey{pow}{directed}
\tkzgr@cmdkey{pow}{order}
\tkzgr@presetkeys{pow}{directed = false, order = {}}
\newcommand*{\tkzGraphMatrixPower}[2][]{%
  \begingroup
  \tkzgr@setkeys{pow}{#1}%
  \directlua{tkzgraph.matrix_power("\luaescapestring{#2}",
     \tkzgl@bool{pow@directed}, "\luaescapestring{\cmdGR@pow@order}")}%
  \endgroup}
\newcommand*{\tkzGraphWalks}[2][]{\tkzgl@walks{#1}{#2}}
\def\tkzgl@walks#1#2(#3)(#4){%
  \begingroup
  \tkzgr@setkeys{pow}{#1}%
  \directlua{tkzgraph.walks("\luaescapestring{#2}", "\luaescapestring{#3}",
     "\luaescapestring{#4}", \tkzgl@bool{pow@directed})}%
  \endgroup}
\endinput