% Copyright (C) 2010-2019 Olivier Boudeville
%
% This file is part of the Ceylan-Myriad library.
%
% This library is free software: you can redistribute it and/or modify
% it under the terms of the GNU Lesser General Public License or
% the GNU General Public License, as they are published by the Free Software
% Foundation, either version 3 of these Licenses, or (at your option)
% any later version.
% You can also redistribute it and/or modify it under the terms of the
% Mozilla Public License, version 1.1 or later.
%
% This library 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 Lesser General Public License and the GNU General Public License
% for more details.
%
% You should have received a copy of the GNU Lesser General Public
% License, of the GNU General Public License and of the Mozilla Public License
% along with this library.
% If not, see <http://www.gnu.org/licenses/> and
% <http://www.mozilla.org/MPL/>.
%
% Author: Olivier Boudeville [olivier (dot) boudeville (at) esperide (dot) com]
% Creation date: Monday, February 15, 2010.


% Gathering of various facilities for color management.
%
-module(gui_color).



% Colors.
%
% Colors are designated by {R,G,B}, or as one of the predefined names, like red,
% green, blue, white, black, grey, or yellow.
%
% For example {0,0,0} is black and {255,255,255} is white.


% Color-related operations.
%
-export([ get_colors/0, get_color/1, get_color_for_gnuplot/1,
		  get_random_colors/1 ]).



% For related defines:
-include("gui.hrl").



-type color_by_name() :: atom().

% No alpha coordinate here:
-type color_by_decimal() :: { byte(), byte(), byte() } | 'none'.

-type color_by_decimal_with_alpha() :: { byte(), byte(), byte(), byte() }
										 | 'none'.


-type color() :: color_by_name() | color_by_decimal().



-export_type ([ color_by_name/0,
				color_by_decimal/0, color_by_decimal_with_alpha/0,
				color/0 ]).




% Color section.

% Here colors are defined as a triplet of color components: {R,G,B}, see the
% color_by_decimal() type.
%
% For example {0,0,0} is black and {255,255,255} is white.




% Returns the list of known { color_name, ColorDefinition } associations.
%
-spec get_colors() -> [ { color_by_name(), color_by_decimal() } ].
get_colors() ->

	% No less than 141 color definitions follow, based on:
	% www.uni-hamburg.de/Wiss/FB/15/Sustainability/schneider/gnuplot/colors.htm

	[

  { aliceblue,            { 240, 248, 255 } },
  { antiquewhite,         { 250, 235, 215 } },
  { aqua,                 {   0, 255, 255 } },
  { aquamarine,           { 127, 255, 212 } },
  { azure,                { 240, 255, 255 } },
  { beige,                { 245, 245, 220 } },
  { bisque,               { 255, 228, 196 } },
  { black,                {   0,   0,   0 } },
  { blanchedalmond,       { 255, 235, 205 } },
  { blue,                 {   0,   0, 255 } },
  { blueviolet,           { 138,  43, 226 } },
  { brown,                { 165,  42,  42 } },
  { burlywood,            { 222, 184, 135 } },
  { cadetblue,            {  95, 158, 160 } },
  { chartreuse,           { 127, 255,   0 } },
  { chocolate,            { 210, 105,  30 } },
  { coral,                { 255, 127,  80 } },
  { cornflowerblue,       { 100, 149, 237 } },
  { cornsilk,             { 255, 248, 220 } },
  { crimson,              { 220,  20,  60 } },
  { cyan,                 {   0, 255, 255 } },
  { darkblue,             {   0,   0, 139 } },
  { darkcyan,             {   0, 139, 139 } },
  { darkgoldenrod,        { 184, 134,  11 } },
  { darkgray,             { 169, 169, 169 } },
  { darkgreen,            {   0, 100,   0 } },
  { darkkhaki,            { 189, 183, 107 } },
  { darkmagenta,          { 139,   0, 139 } },
  { darkolivegreen,       {  85, 107, 47  } },
  { darkorange,           { 255, 140,  0  } },
  { darkorchid,           { 153,  50, 204 } },
  { darkred,              { 139,   0,   0 } },
  { darksalmon,           { 233, 150, 122 } },
  { darkseagreen,         { 143, 188, 143 } },
  { darkslateblue,        {  72,  61, 139 } },
  { darkslategray,        {  47,  79,  79 } },
  { darkturquoise,        {   0, 206, 209 } },
  { darkviolet,           { 148,   0, 211 } },
  { deeppink,             { 255,  20, 147 } },
  { deepskyblue,          {   0, 191, 255 } },
  { dimgray,              { 105, 105, 105 } },
  { dodgerblue,           {  30, 144, 255 } },
  { firebrick,            { 178,  34, 34  } },
  { floralwhite,          { 255, 250, 240 } },
  { forestgreen,          {  34, 139,  34 } },
  { fuchsia,              { 255,   0, 255 } },
  { gainsboro,            { 220, 220, 220 } },
  { ghostwhite,           { 248, 248, 255 } },
  { gold,                 { 255, 215,   0 } },
  { goldenrod,            { 218, 165,  32 } },
  { gray,                 { 127, 127, 127 } },
  { green,                {   0, 128,   0 } },
  { greenyellow,          { 173, 255,  47 } },
  { honeydew,             { 240, 255, 240 } },
  { hotpink,              { 255, 105, 180 } },
  { indianred,            { 205,  92,  92 } },
  { indigo,               {  75,   0, 130 } },
  { ivory,                { 255, 255, 240 } },
  { khaki,                { 240, 230, 140 } },
  { lavender,             { 230, 230, 250 } },
  { lavenderblush,        { 255, 240, 245 } },
  { lawngreen,            { 124, 252,   0 } },
  { lemonchiffon,         { 255, 250, 205 } },
  { lightblue,            { 173, 216, 230 } },
  { lightcoral,           { 240, 128, 128 } },
  { lightcyan,            { 224, 255, 255 } },
  { lightgoldenrodyellow, { 250, 250, 210 } },
  { lightgreen,           { 144, 238, 144 } },
  { lightgrey,            { 211, 211, 211 } },
  { lightpink,            { 255, 182, 193 } },
  { lightsalmon,          { 255, 160, 122 } },
  { lightseagreen,        {  32, 178, 170 } },
  { lightskyblue,         { 135, 206, 250 } },
  { lightslategray,       { 119, 136, 153 } },
  { lightsteelblue,       { 176, 196, 222 } },
  { lightyellow,          { 255, 255, 224 } },
  { lime,                 {   0, 255,   0 } },
  { limegreen,            {  50, 205,  50 } },
  { linen,                { 250, 240, 230 } },
  { magenta,              { 255,   0, 255 } },
  { maroon,               { 128,   0,   0 } },
  { mediumaquamarine,     { 102, 205, 170 } },
  { mediumblue,           {   0,   0, 205 } },
  { mediumorchid,         { 186,  85, 211 } },
  { mediumpurple,         { 147, 112, 219 } },
  { mediumseagreen,       {  60, 179, 113 } },
  { mediumslateblue,      { 123, 104, 238 } },
  { mediumspringgreen,    {   0, 250, 154 } },
  { mediumturquoise,      {  72, 209, 204 } },
  { mediumvioletred,      { 199,  21, 133 } },
  { midnightblue,         {  25,  25, 112 } },
  { mintcream,            { 245, 255, 250 } },
  { mistyrose,            { 255, 228, 225 } },
  { moccasin,             { 255, 228, 181 } },
  { navajowhite,          { 255, 222, 173 } },
  { navy,                 {   0,   0, 128 } },
  { navyblue,             { 159, 175, 223 } },
  { oldlace,              { 253, 245, 230 } },
  { olive,                { 128, 128,   0 } },
  { olivedrab,            { 107, 142,  35 } },
  { orange,               { 255, 165,   0 } },
  { orangered,            { 255,  69,   0 } },
  { orchid,               { 218, 112, 214 } },
  { palegoldenrod,        { 238, 232, 170 } },
  { palegreen,            { 152, 251, 152 } },
  { paleturquoise,        { 175, 238, 238 } },
  { palevioletred,        { 219, 112, 147 } },
  { papayawhip,           { 255, 239, 213 } },
  { peachpuff,            { 255, 218, 185 } },
  { peru,                 { 205, 133,  63 } },
  { pink,                 { 255, 192, 203 } },
  { plum,                 { 221, 160, 221 } },
  { powderblue,           { 176, 224, 230 } },
  { purple,               { 128,   0, 128 } },
  { red,                  { 255,   0,   0 } },
  { rosybrown,            { 188, 143, 143 } },
  { royalblue,            {  65, 105, 225 } },
  { saddlebrown,          { 139,  69,  19 } },
  { salmon,               { 250, 128, 114 } },
  { sandybrown,           { 244, 164,  96 } },
  { seagreen,             { 46,  139,  87 } },
  { seashell,             { 255, 245, 238 } },
  { sienna,               { 160,  82,  45 } },
  { silver,               { 192, 192, 192 } },
  { skyblue,              { 135, 206, 235 } },
  { slateblue,            { 106,  90, 205 } },
  { slategray,            { 112, 128, 144 } },
  { snow,                 { 255, 250, 250 } },
  { springgreen,          {   0, 255, 127 } },
  { steelblue,            {  70, 130, 180 } },
  { tan,                  { 210, 180, 140 } },
  { teal,                 {   0, 128, 128 } },
  { thistle,              { 216, 191, 216 } },
  { tomato,               { 255,  99,  71 } },
  { turquoise,            {  64, 224, 208 } },
  { violet,               { 238, 130, 238 } },
  { wheat,                { 245, 222, 179 } },
  { white,                { 255, 255, 255 } },
  { whitesmoke,           { 245, 245, 245 } },
  { yellow,               { 255, 255, 0   } },
  { yellowgreen,          { 139, 205,  50 } }

	].



% Returns the RGB definition of the color specified by name (atom) or directly
% as a triplet of color components.
%
-spec get_color( color() | 'none' ) -> color_by_decimal().
get_color( Color={ _R, _G, _B } ) ->
	% Optimised for this most frequent form (first pattern):
	Color;

get_color( none ) ->
	% none is a special case, for example to disable filling (transparent):
	none;


get_color( ColorName ) when is_atom( ColorName ) ->

	case proplists:get_value( ColorName, get_colors() ) of

		undefined ->
			throw( { unknown_color, ColorName } );

		Color ->
			Color

	end.



% Returns a stringified representation for gnuplot of the specified color.
%
-spec get_color_for_gnuplot( color() ) -> string().
get_color_for_gnuplot( _Color={ _R, _G, _B } ) ->
	throw( hexadecimal_conversion_not_implemented );

get_color_for_gnuplot( ColorName ) ->
	io_lib:format( "~s", [ ColorName ] ).



% Returns a list of the specified number of different colors.
%
-spec get_random_colors( basic_utils:count() ) -> [ color_by_decimal() ].
get_random_colors( ColorCount ) ->

	AllColors = get_colors(),

	% Only keep RBG values, not the atom-based name:
	%
	[ RGB || { _Name, RGB } <-
				 list_utils:draw_elements_from( AllColors, ColorCount ) ].