#!/usr/bin/env ruby
#
# tcolor --
#   simple color editor which supports RGB, HSB and CYM color space
#
# Copyright (C) 1998 Takaaki Tateishi(ttate@jaist.ac.jp)
# last update: Thu Jun 18 06:32:35 JST 1998
#

require "tk"


# use TkVariable instance for the variable which is changed by Tk interpreter

$colorSpace = TkVariable.new(:rgb)
$master = nil
$red = 65535
$green = 0
$blue = 0
$color = "#ffff00000000"
$updating = TkVariable.new(0)
$autoUpdate = TkVariable.new(1)
$name = TkVariable.new($color)
$command = TkVariable.new("print(%%,\"\n\")")
# $command = TkVariable.new("")
$label1 = TkVariable.new("label1")
$label2 = TkVariable.new("label2")
$label3 = TkVariable.new("label3")


# setup the entry of the resourc database
if (TkVarAccess.new('tcl_platform')['platform'] == 'unix')
  TkOptionDB.add('*Entry.background', 'white')
end


# methods for events

def rgbToHsv(red,green,blue)

  if ( red > green )
    max = red
    min = green
  else
    max = green
    min = red
  end

  if ( blue > max )
    max = blue
  else
    if ( blue < min )
      min = blue
    end
  end

  range = max - min

  if ( max == 0 )
    sat = 0.0
  else
    sat = (max-min)/max
  end

  if ( sat == 0 )
    hue = 0.0
  else
    rc = (max-red)/range
    gc = (max-green)/range
    bc = (max-blue)/range
    if ( red == max )
      hue = 0.166667 * (bc - gc)
    else
      if ( green == max )
	hue = 0.166667 * (2.0 + rc - bc)
      else
	hue = 0.166667 * (4.0 + gc - rc)
      end
    end
    if ( hue < 0.0 )
      hue = hue + 1.0
    end
  end

  [hue,sat,max/65535]
end


def hsbToRgb(hue,sat,value)
  v = 65535.0 * value
  if( sat == 0 )
    ans = [v,v,v]
  else
    hue = hue*6.0
    if ( hue >= 6 )
      hue = 0.0
    end
    i = hue.to_i
    f = hue - i
    p = 65535.0 * value * (1.0 - sat)
    q = 65535.0 * value * (1.0 - (sat * f))
    t = 65535.0 * value * (1.0 - (sat * (1.0 - f)))
    case i
    when 0
      ans = [v,t,p]
    when 1
      ans = [q,v,p]
    when 2
      ans = [p,v,t]
    when 3
      ans = [p,q,v]
    when 4
      ans = [t,p,v]
    when 5
      ans = [v,p,q]
    else
      raise(eException,"i value #{i} is out of range")
    end
  end
  return ans
end


def _null_binding
  Module.new.instance_eval{binding}
end
private :_null_binding

def doUpdate 
  newCmd = $command.to_s.gsub("%%","\"#{$color}\"")
  eval(newCmd, _null_binding)
end


def tc_scaleChanged
  if( $updating.to_i == 1 )
    return 
  end

  $master = :scale if $master == nil

  scale1 = $root.middle.middle.scale1
  scale2 = $root.middle.middle.scale2
  scale3 = $root.middle.middle.scale3

  case $colorSpace.value.intern
  when :rgb
    $red = (scale1.get * 65.535).to_i
    $green = (scale2.get * 65.535).to_i
    $blue = (scale3.get * 65.535).to_i
  when :cmy
    $red = (65535 - scale1.get * 65.535).to_i
    $green = (65535 - scale2.get * 65.535).to_i
    $blue = (65535 - scale3.get * 65.535).to_i        
  when :hsb
    list = hsbToRgb(scale1.get / 1000.0,
		    scale2.get / 1000.0,
		    scale3.get / 1000.0)
    $red = list[0]
    $green = list[1]
    $blue = list[2]
  else
    raise(Exception,"unknown colorSpace")
  end
  $color = format("#%04x%04x%04x",$red.to_i,$green.to_i,$blue.to_i)
  $name.value = $color if $master == :scale
  $root.middle.right.set_color($color)
  if( $autoUpdate.to_i == 1 )
    doUpdate
  end
  Tk.update(true)
  $master = nil if $master == :scale
end


def tc_setScales
  $updating.value = 1

  scale1 = $root.middle.middle.scale1
  scale2 = $root.middle.middle.scale2
  scale3 = $root.middle.middle.scale3
  
  case $colorSpace.value.intern
  when :rgb
    scale1.set($red / 65.535)
    scale2.set($green / 65.535)
    scale3.set($blue / 65.535)
  when :cmy
    scale1.set((65535 - $red) / 65.535)
    scale2.set((65535 - $green) / 65.535)
    scale3.set((65535 - $blue) / 65.535)
  when :hsb
    list = rgbToHsv($red,$green,$blue)
    scale1.set( list[0] * 1000.0 )
    scale2.set( list[1] * 1000.0 )
    scale3.set( list[2] * 1000.0 )
  else
    raise(Exception,"unknown colorSpace")
  end

  $updating.value = 0
end


def tc_loadNamedColor(name)
  $name.value = name
  $master = :name if $master == nil
  if name[0,1] != "#" 
    list = TkWinfo.rgb($root.middle.right.swatch,name)
    $red = list[0]
    $green = list[1]
    $blue = list[2]
  else
    case name.length
    when 4
      fmt = /#(.{1})(.{1})(.{1})/
      shift = 12
    when 7
      fmt = /#(.{2})(.{2})(.{2})/
      shift = 8
    when 10
      fmt = /#(.{3})(.{3})(.{3})/
      shift = 4
    when 13
      fmt = /#(.{4})(.{4})(.{4})/
      shift = 0
    else
      raise(eException,"syntax error in color name \"#{name}\"")
    end
    name.scan(fmt){|strlist|
      if strlist.length != 3
	raise(eException,"syntax error in color name \"#{name}\"")
      end
      $red = strlist[0].hex
      $green = strlist[1].hex
      $blue = strlist[2].hex
    }
    $red = $red << shift
    $green = $green << shift
    $blue = $blue << shift
  end
  
  tc_setScales
  $color = format("#%04x%04x%04x",$red,$green,$blue)
  $root.middle.right.set_color($color)
  if $autoUpdate.to_i == 1
    doUpdate
  end
  Tk.update(true)
  $master = nil if $master == :name
end


def changeColorSpace(space)
  case space
  when :rgb
    $label1.value = "Red"
    $label2.value = "Green"
    $label3.value = "Blue"
  when :cmy
    $label1.value = "Cyan"
    $label2.value = "Magenta"
    $label3.value = "Yellow"
  when :hsb
    $label1.value = "Hue"
    $label2.value = "Saturation"
    $label3.value = "Brightness"
  end
  tc_setScales
end


# menu

class TkColorMenuFrame<TkFrame
  def initialize(parent)
    super(parent,
	  "relief"=>"raised",
	  "borderwidth"=>"2")

    # File menubutton
    @file = TkMenubutton.new(self){|button|

      # File menu
      @file_menu = TkMenu.new(button){
	add "radio",
	  "label" => "RGB color space",
	  "variable" => $colorSpace,
	  "value" => :rgb,
	  "underline" => "0",
	  "command" => proc{changeColorSpace(:rgb)}
	add "radio",
	  "label" => "CMY color space",
	  "variable" => $colorSpace,
	  "value" => :cmy,
	  "underline" => "0",
	  "command" => proc{changeColorSpace(:cmy)}
	add "radio",
	  "label" => "HSB color space",
	  "variable" => $colorSpace,
	  "value" => :hsb,
	  "underline" => "0",
	  "command" => proc{changeColorSpace(:hsb)}
	add "separator"
	add "radio",
	  "label" => "Automatic updates",
	  "variable" => $autoUpdate,
	  "value" => "1",
	  "underline" => "0"
	add "radio",
	  "label" => "Manual updates",
	  "variable" => $autoUpdate,
	  "value" => "0",
	  "underline" => "0"
	add "separator"
	add "command",
	  "label" => "Exit program",
	  "underline" => "0",
	  "command" => proc{exit}
      }
      
      # assign File menu to File button
      menu @file_menu

      text "File"
      underline "0"
    }.pack("side"=>"left")

    self
  end
end


# bottom frame
class TkColorBotFrame<TkFrame
  def initialize(parent)
    super(parent,
	  "relief"=> "raised",
	  "borderwidth"=> 2)

    @commandLabel = TkLabel.new(self,
				"text"=> "Command:")
    @command = TkEntry.new(self,
			   "relief"=> "sunken",
			   "borderwidth"=> "2",
			   "textvariable"=> $command,
			   "font"=> "-Adobe-Courier-Medium-R-Normal--*-120-*-*-*-*-*-*")
    @update = TkButton.new(self,
			   "text"=> "Update",
			   "command"=> proc{doUpdate})
    @commandLabel.pack("side"=>"left")
    @update.pack("side"=>"right","pady"=>".1c","padx"=>".25c")
    @command.pack("expand"=>"yes","fill"=>"x","ipadx"=>".25c")

    self
  end
end    


# left side frame of middle level
class TkColorMiddleLeftFrame<TkFrame
  def initialize(parent)
    super(parent)

    for i in ["/usr/local/lib/X11rgb.txt","/usr/lib/X11/rgb.txt",
	"/X11/R5/lib/X11/rgb.txt","/X11/R4/lib/rgb/rgb.txt",
	"/usr/openwin/lib/X11/rgb.txt"]
      if !File.readable?(i)
	next
      end
      f = File.open(i)
      @scroll = TkScrollbar.new(self,
				"orient"=>"vertical",
				"relief"=>"sunken",
				"borderwidth"=>"2")
      @scroll.pack("side"=>"right","fill"=>"y")
      @names = TkListbox.new(self,
			     "width"=>"20",
			     "height"=>"12",
			     "yscrollcommand"=> proc{|first,last| @scroll.set first,last},
			     "relief"=>"sunken",
			     "borderwidth"=>"2",
			     "exportselection"=>"false")
      @scroll.command(proc{|*args| @names.yview(*args)})
      @names.bind("Double-1",proc{
		    tc_loadNamedColor(@names.get(@names.curselection))})
      @names.pack("side"=>"left")
      while (line = f.gets)
	line.chop!
	linelist = line.split(/[ \t]+/)
	if linelist.length == 4
	  @names.insert("end",linelist[3])
	end
      end
      f.close
      break
    end

    self
  end
end


# middle frame of middle level
class TkColorMiddleMiddleFrame<TkFrame
  attr_reader :scale1, :scale2, :scale3

  def initialize(parent)
    super(parent)

    @f1 = TkFrame.new(self)
    @f2 = TkFrame.new(self)
    @f3 = TkFrame.new(self)
    @f4 = TkFrame.new(self)

    for f in [@f1,@f2,@f3]
      f.pack("side"=>"top","expand"=>"yes")
    end
    @f4.pack("side"=>"top","expand"=>"yes","fill"=>"x")

    @label1 = TkLabel.new(self,"textvariable"=>$label1)
    @scale1 = TkScale.new(self,"from"=>"0","to"=>"1000","length"=>"6c",
			  "orient"=>"horizontal",
			  "command"=>proc{tc_scaleChanged})
    @scale1.pack("side"=>"top","anchor"=>"w")
    @label1.pack("side"=>"top","anchor"=>"w")

    @label2 = TkLabel.new(self,"textvariable"=>$label2)
    @scale2 = TkScale.new(self,"from"=>"0","to"=>"1000","length"=>"6c",
			  "orient"=>"horizontal",
			  "command"=>proc{tc_scaleChanged})
    @scale2.pack("side"=>"top","anchor"=>"w")
    @label2.pack("side"=>"top","anchor"=>"w")

    @label3 = TkLabel.new(self,"textvariable"=>$label3)
    @scale3 = TkScale.new(self,"from"=>"0","to"=>"1000","length"=>"6c",
			  "orient"=>"horizontal",
			  "command"=>proc{tc_scaleChanged})
    @scale3.pack("side"=>"top","anchor"=>"w")
    @label3.pack("side"=>"top","anchor"=>"w")

    @nameLabel = TkLabel.new(self,"text"=>"Name:")
    @name = TkEntry.new(self,"relief"=>"sunken","borderwidth"=>"2",
			"textvariable"=>$name,"width"=>"10",
			"font"=>"-Adobe-Courier-Medium-R-Normal--*-120-*-*-*-*-*-*")
    @nameLabel.pack("side"=>"left")
    @name.pack("side"=>"right", "expand"=>"1", "fill"=>"x")
    @name.bind("Return",proc{tc_loadNamedColor $name.to_s})

    self
  end
end


class TkColorMiddleRightFrame<TkFrame
  attr_reader :swatch

  def initialize(parent)
    super(parent)
    @swatch = TkFrame.new(self, "width"=>"2c", "height"=>"5c",
			  "background"=>$color)
    @value = TkLabel.new(self, 
			 "text"=>$color,
			 "width"=>"13",
			 "font"=>"-Adobe-Courier-Medium-R-Normal--*-120-*-*-*-*-*-*")
    @swatch.pack("side"=>"top","expand"=>"yes","fill"=>"both")
    @value.pack("side"=>"bottom","pady"=>".25c")

    self
  end

  def set_color(color)
    @swatch["background"] = color
    @value["text"] = color
  end
end



# middle level frame
class TkColorMiddleFrame<TkFrame
  attr_reader :left, :middle, :right

  def initialize(parent)
    super(parent,
	  "relief"=> "raised",
	  "borderwidth"=> "2")

    @left = TkColorMiddleLeftFrame.new(self)
    @left.pack("side"=>"left","padx"=>".25c","pady"=>".25c")

    @middle = TkColorMiddleMiddleFrame.new(self)
    @middle.pack("side"=>"left","expand"=>"yes","fill"=>"y")

    @right = TkColorMiddleRightFrame.new(self)
    @right.pack("side"=>"left","padx"=>".25c","pady"=>".25c","anchor"=>"s")

    self
  end
end


class TkColor<TkRoot
  attr_reader :menu, :bottom, :middle

  def initialize(*args)
    super(*args)
    @menu = TkColorMenuFrame.new(self)
    @menu.pack("side"=>"top", "fill"=>"x")

    @bottom = TkColorBotFrame.new(self)
    @bottom.pack("side"=>"bottom","fill"=>"x")

    @middle = TkColorMiddleFrame.new(self)
    @middle.pack("side"=>"top","fill"=>"both")

    self
  end
end


$root = TkColor.new
changeColorSpace :rgb

# start eventloop
Tk.mainloop
