#encding:GBK

require 'tk'

module Const

  WIDTH_OF_PANEL = 370

  HEIGHT_OF_PANEL = 520

  SIZE_OF_BUTTON_H = 60

  SIZE_OF_BUTTON_W = 80

  HEIGHT_OF_DISPLAY_FRAME = 90

  HEIGHT_OF_VALUE_LABEL = 30

  HEIGHT_OF_OPERATION_LABEL = 20

  BORDER_WIDTH = 2

  PADX = 10

  PADY = 10

  OP_ARRAY = ["%","sqrt","x^2","1/x","CE","C","DEL","/","","","","*","","","","-","","","","+","+/-","",".","="]

end

include Const

$value_tk_var = TkVariable.new(0)

$operate_tk_var = TkVariable.new

$Font = TkFont.new('arial 18')

class ButtonInfor

  attr_accessor :x, :y

  protected :x=, :y=

  def initialize(x=0,y=0)

    @x , @y = x , y

  end

end

module Work

  def number(num)

    if $value_tk_var.value == ""

      $value_tk_var.value = num

    elsif $value_tk_var.value == '-0'

      $value_tk_var.value = $value_tk_var.value.chop + num

      puts "bbbb"

    elsif $value_tk_var.value != ""

      $value_tk_var.value += num

    end

  end

  def point

    unless /\./ =~ $value_tk_var.value

      $value_tk_var.value += "."

    end

  end

  def calcu( key )

    unless (/\+/ =~ $operate_tk_var.value || /-/ =~ $operate_tk_var.value || /\*/ =~ $operate_tk_var.value || /\// =~ $operate_tk_var.value)

      $operate_tk_var.value = $value_tk_var.value + " " + key

      $value_tk_var.value = 0

    else

      $operate_tk_var.value = $operate_tk_var.value.chop + key

    end

  end

  def equl

    operator_ = $operate_tk_var.value[$operate_tk_var.value.size-1]

    $operate_tk_var.value = $operate_tk_var.value.chop

    num2 = (/\./ =~ $value_tk_var.value) ? $value_tk_var.value.to_f : $value_tk_var.value.to_i

    num1 = (/\./ =~ $operate_tk_var.value) ? $operate_tk_var.value.to_f : $operate_tk_var.value.to_i

    case operator_

    when "+"

      $value_tk_var.value = ( num1 + num2 ).to_s

    when "-"

      $value_tk_var.value = ( num1 - num2 ).to_s

    when "*"

      $value_tk_var.value = ( num1 * num2 ).to_s

    when "/"

      if num2 == 0 || num2 == 0.0

        $value_tk_var.value = "CANNOT DEVIDED BY 0!"

      else

        $value_tk_var.value = ( num1 / num2 ).to_s

      end

    end

    $operate_tk_var.value = nil

  end

  def clear(op)

    $value_tk_var.value = 0

    $operate_tk_var.value = nil if (op == "C")

  end

  def del

    $value_tk_var.value = $value_tk_var.value.chop

  end

  def sqrt_

    $value_tk_var.value = Math.sqrt($value_tk_var.value.to_f)

  end

  def sq_

    $value_tk_var.value = $value_tk_var.value.to_f * $value_tk_var.value.to_f

  end

  def devide_one

    $value_tk_var.value = 1/($value_tk_var.value.to_f)

  end

  def negate

    if $value_tk_var.value[0] != '-'

      $value_tk_var.value = "-" + $value_tk_var.value

    else

      $value_tk_var.value = $value_tk_var.value.reverse.chop.reverse

    end

  end

  def get_pos_hash

    tmp = Hash.new

    (0..23).each do |i|

      tmp[OP_ARRAY[i]]=ButtonInfor.new((i%4)*(PADX+SIZE_OF_BUTTON_W),(i/4)*(PADY+SIZE_OF_BUTTON_H))

    end

    return tmp

  end

  module_function :number , :point , :clear , :calcu , :equl , :del , :sqrt_ , :sq_ , :devide_one , :get_pos_hash ,:negate

end

#创建主窗口

root = TkRoot.new do

  title "SHH's Calculator";

  geometry WIDTH_OF_PANEL.to_s + "x" + HEIGHT_OF_PANEL.to_s;

end

operat_frame = TkFrame.new do

  relief 'groove'

  pack('fill' => 'x')

  borderwidth BORDER_WIDTH

  padx PADX

  pady PADY

  place:'height' => HEIGHT_OF_PANEL-HEIGHT_OF_DISPLAY_FRAME , 'width' => WIDTH_OF_PANEL , 'x' => 0 , 'y' => HEIGHT_OF_DISPLAY_FRAME

  background "LightCyan"

end

display_frame = TkFrame.new do

  relief 'groove'

  pack('fill' => 'x')

  borderwidth BORDER_WIDTH

  padx PADX

  pady PADY

  place:'height' => HEIGHT_OF_DISPLAY_FRAME , 'width' => WIDTH_OF_PANEL , 'x' => 0 , 'y' => 0

  background "lightblue"

end

value_label = TkLabel.new(display_frame) do

  relief 'groove'

  pack('fill' => 'x')

  borderwidth BORDER_WIDTH

  textvariable

  font $Font

  place:'height' => HEIGHT_OF_VALUE_LABEL , 'width' => WIDTH_OF_PANEL - PADX * 2 , 'x' => 0 , 'y' => 0

end

operation_label = TkLabel.new(display_frame) do

  relief 'groove'

  pack('fill' => 'x')

  borderwidth BORDER_WIDTH

  textvariable

  font TkFont.new('arial 10')

  place:'height' => HEIGHT_OF_OPERATION_LABEL , 'width' => WIDTH_OF_PANEL * 0.618  , 'x' => WIDTH_OF_PANEL * (1-0.618) - PADX * 2 , 'y' => HEIGHT_OF_VALUE_LABEL + PADY

end

value_label['textvariable'] = $value_tk_var

operation_label['textvariable'] = $operate_tk_var

Work.get_pos_hash().each do |key,value|

  TkButton.new(operat_frame) do

    font "Consolas 15"

    place:'height' => SIZE_OF_BUTTON_H , 'width' => SIZE_OF_BUTTON_W , 'x' => value.x , 'y' => value.y

    text key

    background (("".."") === key)? "Gainsboro" : "Gray"

    command do

      case key

      when ("".."")

        Work.number(key)

      when "."

        Work.point()

      when "+","-","*","/"

        Work.calcu(key)

      when "="

        Work.equl()

      when "CE","C"

        Work.clear(key)

      when "DEL"

        Work.del()

      when "sqrt"

        Work.sqrt_()

      when "x^2"

        Work.sq_()

      when "1/x"

        Work.devide_one()

      when "+/-"

        Work.negate()

      end

    end

  end

end

Tk.mainloop