checkers

os.loadAPI("button")
m = peripheral.wrap("top")
rednet.open("bottom")
local board={}
local currentTurn
local turtles={}
local redRem=0
local blkRem=0

function loadBoard()
  for i = 1,8 do
     board[i] = {}
     turtles[i] = {}
  end
end

function setPiece(a,b,color)
  board[a][b]=color
end

function setTurtle(a,b,id)
  turtles[a][b]=id
end

function getTurtle(a,b)
   return(turtles[a][b])
end

function getPiece(a,b)
  return(board[a][b])
end

function newGame()
  for i = 1,7,2 do
     tInc = (i-1)/2
     setPiece(i,1,colors.gray)
     setTurtle(i,1,236+tInc)
     setPiece(i+1,2,colors.gray)
     setTurtle(i+1,2,232+tInc)
     setPiece(i,3,colors.gray)
     setTurtle(i,3,228+tInc)
     setPiece(i+1,6,colors.pink)
     setTurtle(i+1,6,216+tInc)
     setPiece(i,7,colors.pink)
     setTurtle(i,7,220+tInc)
     setPiece(i+1,8,colors.pink)
     setTurtle(i+1,8,224+tInc)
  end
  currentTurn = colors.pink
  for i = 216,239 do
     rednet.send(i,"goHome")
  end
end

function switchTurn()
   if currentTurn == colors.pink then
      currentTurn = colors.gray
   else
      currentTurn = colors.pink
   end
   dispTurn()
end

function dispTurn()
  m.setBackgroundColor(colors.white)
  m.setTextColor(colors.green)
  m.setCursorPos(29,2)
  m.write("Turn: ")
  m.setTextColor(currentTurn)
  if currentTurn == colors.pink then
     m.write("Red  ")
  else
     m.write("Black")
  end
  dispRemaining()
end

function dispRemaining()
  m.setBackgroundColor(colors.white)
  m.setTextColor(colors.green)
  m.setCursorPos(29,7)
  m.write("Pieces Left:")
  m.setTextColor(colors.pink)
  m.setCursorPos(29,8)
  m.write("R:"..redRem.." : ")
  m.setTextColor(colors.black)
  m.write("B:"..blkRem.."  ")
end

function drawPieces()
  local tempcolor
  for a = 1,8 do
    for b = 1,8 do
      tempcolor = getPiece(a,b)
      if (tempcolor ~= nil) then
        m.setTextColor(tempcolor)
        drawPiece(a,b)
      end
    end
  end
end

function getXY(a,b)
   x = a*3
   y = b*2
   return x,y
end

function drawPiece(a,b)
  x,y = getXY(a,b)
  m.setBackgroundColor(getColor(x,y))
  x,y = getCorner(x,y)
  x = x+1
  m.setCursorPos(x,y)
  m.write("X")
end

function getCorner(x,y)
  if y%2~=0 then y=y-1 end
  if x%3~=0 then x=x-1 end
  if x%3~=0 then x=x-1 end
  return x,y
end

function getBoardPos(x,y)
  x,y = getCorner(x,y)
  x = x/3
  y = y/2
  return x,y
end

function getColor(x,y)
  x,y = getCorner(x,y)
  local invert = false
  if y%4 == 0 then invert = true end
  if (x%2==0) then
     if invert then return(colors.black) else return(colors.red) end
  else
     if invert then return(colors.red) else return(colors.black) end
  end
end

function background(bgcolor)
   m.setBackgroundColor(bgcolor)
   for j = 1, 20 do
      for i = 1,39 do
        m.setCursorPos(i,j)
        m.write(" ")
      end
   end
end

function drawBoard()
   for y = 2,17 do
     for x = 3,26 do
       m.setBackgroundColor(getColor(x,y))
       m.setCursorPos(x,y)
       m.write(" ")
     end
   end
   message(30,5,"clear",colors.red)
end

function getClick()
   event,side,x,y = os.pullEvent("monitor_touch")
   return x,y
end

function anyJumps()
   local jump = false
   for a = 1,8 do
      for b = 1,8 do
         if canDouble(a,b) and myTurn(getPiece(a,b)) then
            jump = true
         end
      end
   end
   return jump
end

function waitPlayer()
   local tempColor
   local valid = false
   x,y = getClick()
   if button.checkxy(x,y) then return true end
   a,b = getBoardPos(x,y)
   if a<1 or b<1 or a>8 or b>8 then return false end
   if getPiece(a,b) ~= nil and myTurn(getPiece(a,b)) then
     message(30,3,a..":"..b,colors.blue)
     x,y = getClick()
     a2,b2 = getBoardPos(x,y)
     message(30,4,a2..":"..b2,colors.green)
     if tryMove(a,b,a2,b2) == false then
       if tryJump(a,b,a2,b2) then
          switchTurn()
       end
     end
   end
   message(30,3,"clear",colors.blue)
   message(30,4,"clear",colors.blue)
end

function myTurn(color)
   if currentTurn == colors.pink then
      if color ~= colors.pink and color ~= colors.blue then return false end
   else
      if color ~= colors.gray and color ~= colors.white then return false end
   end
   return true
end

function isKing(a,b)
  if getPiece(a,b) == colors.white or getPiece(a,b) == colors.blue then
     return true
  else
     return false
  end
end

function isValidMove(a,b,a2,b2)
   local tempColor = getPiece(a,b)
   if getPiece(a2,b2) ~= nil then
     return false
   end
   if tempColor == colors.pink then
      if b < b2 then return false end
   elseif tempColor == colors.gray then
      if b > b2 then return false end
   end
   return true
end

function tryMove(a,b,a2,b2)
   if math.abs(a-a2) ~= 1 or math.abs(b-b2) ~= 1 then
     return false
   end
   if anyJumps() then
      message(30,5,"Must Jump!",colors.red)
      return false
   end
   if isValidMove(a,b,a2,b2) then
      movePiece(a,b,a2,b2)
      switchTurn()
      return true
   end
   message(30,5,"clear",colors.red)
   return false
end

function isValidJump(a,b,a2,b2)
   if a<1 or a>8 or b<1 or b>8 then return false end
   if a2<1 or a2>8 or b2<1 or b2>8 then return false end
   if math.abs(a-a2)~=2 or math.abs(b-b2)~=2 then
      return false
   end
   local tempColor = getPiece(a,b)
   local jumpColor = getPiece((a+a2)/2,(b+b2)/2)
   if isValidMove(a,b,a2,b2) == false then return false end
   if jumpColor == nil then return false end
   if tempColor == colors.gray or tempColor == colors.white then
      if jumpColor~=colors.pink and jumpColor~=colors.blue then
        return false
      end
   else
      if jumpColor~=colors.gray and jumpColor~=colors.white then
        return false
      end
   end
   return true
end

function canDouble(a2,b2)
  double = false
  if isValidJump(a2,b2,a2+2,b2+2) then double = true end
  if isValidJump(a2,b2,a2-2,b2+2) then double = true end
  if isValidJump(a2,b2,a2+2,b2-2) then double = true end
  if isValidJump(a2,b2,a2-2,b2-2) then double = true end
  return double
end

function updScore(color)
   if color == colors.blue or color == colors.pink then
      redRem = redRem-1
   else
      blkRem = blkRem-1
   end
end

function tryJump(a,b,a2,b2)
   if math.abs(a-a2)~=2 or math.abs(b-b2)~=2 then
      return false
   end
   if isValidJump(a,b,a2,b2) then
      rednet.send(getTurtle((a+a2)/2,(b+b2)/2),"goOut")
      updScore(getPiece((a+a2)/2,(b+b2)/2))
      setPiece((a+a2)/2,(b+b2)/2,nil)
      setTurtle((a+a2)/2,(b+b2)/2,nil)
      movePiece(a,b,a2,b2)
      while canDouble(a2,b2) do
        a = a2
        b = b2
        message(30,5,"Double!",colors.red)
        x,y = getClick()
        a3,b3 = getBoardPos(x,y)
        tryJump(a,b,a3,b3)
      end
      message(30,5,"clear",colors.red)
      return true
   end
   message(30,5,"clear",colors.blue)
   return false
end

function message(x,y,text,color)
   m.setCursorPos(x,y)
   m.setTextColor(color)
   m.setBackgroundColor(colors.white)
   if text == "clear" then
      m.write("          ")
   else
      m.write(text)
   end
end

function isRed(color)
   if color == colors.pink or color == colors.blue then
      return true
   else
      return false
   end
end

function turtleMove(a,b,a2,b2)
   local tempColor = getPiece(a,b)
   local tempTurtle = getTurtle(a,b)
   local msg = ""
   if a<a2 and b>b2 then
      if isRed(tempColor) then msg="fr" else msg="bl" end
   elseif a>a2 and b>b2 then
      if isRed(tempColor) then msg="fl" else msg="br" end
   elseif a<a2 and b<b2 then
      if isRed(tempColor) then msg="br" else msg="fl" end
   elseif a>a2 and b<b2 then
      if isRed(tempColor) then msg="bl" else msg="fr" end
   end
   if math.abs(a-a2) == 1 and math.abs(b-b2) == 1 then
      msg=msg
   else
      msg="j"..msg
   end
   print(a..","..b..":"..msg..":"..getTurtle(a,b))
   rednet.send(getTurtle(a,b),msg)
   local id,msg,dist = rednet.receive(10)
   setTurtle(a,b,nil)
   setTurtle(a2,b2,tempTurtle)
   print(msg)
end

function movePiece(a,b,a2,b2)
   local tempColor = getPiece(a,b)
   if tempColor==colors.pink and b2==1 then
      tempColor=colors.blue
   elseif tempColor==colors.gray and b2==8 then
      tempColor = colors.white
   end
   turtleMove(a,b,a2,b2)
   setPiece(a2,b2,tempColor)
   setPiece(a,b,nil)
   drawBoard()
   drawPieces()
end

function quit()
   shell.run("testOut")
   m.setBackgroundColor(colors.black)
   m.clear()
   os.pullEvent("monitor_touch")
   background(colors.white)
   drawBoard()
   button.setTable("NewGame",new,30,38,15,17)
   button.setTable("Quit",quit,2,7,19,19)
   m.setTextColor(colors.black)
   button.screen()
end

function new()
  redRem = 12
  blkRem = 12
  background(colors.white)
  drawBoard()
  loadBoard()
  newGame()
  drawPieces()
  dispTurn()
  m.setTextColor(colors.black)
  button.setTable("NewGame",new,30,38,15,17)
  button.setTable("Quit",quit,2,7,19,19)
  button.screen()
end

quit()
while true do waitPlayer() end