require 'tk'

$w, $h = 400, 400
$x0, $y0 = 50, 20

$n, $dim = 4, 75

$blank = 16
$puzzle = [nil,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,"blank"]
$goal = [nil,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,"blank"]
$tile = [nil]
$text = [nil]

def linearconflict
  count = 0
  return count
end

def manhattan
  count = 0
  return count
end

def diffeval
  count = 0
  return count
end

def move(index)
  temp = $puzzle[index]
  $puzzle[index]="blank"
  $puzzle[$blank] = temp
  $tile[$blank].fill='black'
  
  puts "text at index=#{$text[index].text}"
  
  $text[$blank].text="#{temp}"
  $tile[index].fill= 'white'
  $blank=index
end

def click(c, e)
  adjacent = false
  index= ((e.x-$x0)/$dim + 1) + (e.y-$y0)/$dim * 4
  row = (index-1)/4+1
  col = index-(row-1)*4
  puts "#{e.x} #{e.y} Index: #{index} at row:#{row} col:#{col}"
  move(index)
end

root = TkRoot.new(:title => 'Sliding Tile Puzzle')
canvas = TkCanvas.new(root, :width => $w, :height => $h, :background => 'black')
canvas.pack

k = 0
while k < $n
  j = 0
  while j < $n
    x, y = $x0 + $dim*j, $y0 + $dim*k
    num = k*$n + j + 1
puts "drawing tile # #{num}: x=#{x}, y=#{y}, to #{x+$dim}, #{y+$dim}, $dim=#{$dim}"
    tile = TkcRectangle.new(canvas, x, y, x+$dim, y + $dim,
       :outline => 'white')
    text = TkcText.new(canvas, x+$dim/2, y+$dim/2, :text => "#{num}",
       :fill =>'white')
    $tile << tile
    $text << text
    j += 1
  end
  k += 1
end

$headings1 = TkcText.new(canvas, 120, $h-70, 
			 :text=>"# misplaced          manhattan          linear",
		         :fill => 'white')

$headings2 = TkcText.new(canvas, 130, $h-55, 
			 :text=>"     tiles               distance          conflict",
		         :fill => 'white')
$evaltext = TkcText.new(canvas, 120, $h-$dim/2, 
			:text => "#{diffeval}                      #{manhattan}                     #{linearconflict}", 
		       :fill => 'white')
#puts "Array of tiles: #{$tile.inspect}"

puts "for white tile: x=#{x}, y=#{y}, to #{x+$dim}, #{y+$dim}, $dim=#{$dim}"
tile.fill = 'white'
text.text = ""

root.bind('1') { |event| click(canvas,event) }
root.bind('q') { exit }
Tk.mainloop