function FirstScreen()
  term.clear()
  term.setCursorPos(1,1)
  write("My First Minining Program")
  sleep(0.5)
end

function setVariables()

  fuelLevel = 0
  x = 0
  z = 0
  y = 0
  f = 0
  DigX = 0
  DigZ = 0
  DigDepth = 0
  OriginX = 0
  OriginZ = 0
  OriginY = 0
  OriginF = 0
  GoBackToY = 0
  GoBackToX = 0
  GoBackToZ = 0
  GoBackToF = 0
  BlocksMined = 1
  BlocksToBeMined = 0
  BlocksMinedPercent = 0
  ErrorMovingCount = 0
  ComputerID = 0
  TurtleID = os.getComputerID()
  TurtleLabel = os.getComputerLabel()

end


function ClearScreen()
  term.clear()
  term.setCursorPos(1,1)
end

function AskForDimension()
  term.setCursorPos(1,1)
  write("Width?")
  term.setCursorPos(1,2)
  input = read()
  DigX = input
  ClearScreen()

  term.setCursorPos(1,1)
  write("Length?")
  term.setCursorPos(1,2)
  input = read()
  DigZ = input
  ClearScreen()

  --term.setCursorPos(1,1)
  --write("Depth?")
  --input = read()
  --DigDepth = input
  --ClearScreen()

  term.setCursorPos(1,1)
  write("Please place unwanted blocks in slot 1 and slot 2")
  term.setCursorPos(1,3)
  write("Press any key to continue")
  input = read()
end

function CalculatePercent()
	BlocksMinedPercent = tonumber(BlocksMined) / tonumber(BlocksToBeMined) * 100
	return BlocksMinedPercent
end

function AskForCoordinate()
  ClearScreen()

  term.setCursorPos(1,1)
  write("What is the ComputerID?")
  input = read()
  ComputerID = input
  ClearScreen()

  term.setCursorPos(1,1)
  write("What is the x-Position of the Mining Turtle?")
  input = read()
  x = input
  ClearScreen()

  term.setCursorPos(1,1)
  write("What is the z-Position of the Mining Turtle?")
  input = read()
  z = input
  ClearScreen()

  term.setCursorPos(1,1)
  write("What is the y-Position of the Mining Turtle?")
  input = read()
  y = input
  ClearScreen()

  term.setCursorPos(1,1)
  write("What is the direction of the Mining Turtle? (0 = south, 1 = west, 2 = north, 3 = east)")
  input = read()
  f = input
  ClearScreen()

  term.setCursorPos(1,1)
  write("Is that right? (yes/no)")

  term.setCursorPos(1,2)
  write("x: "..x.."")

  term.setCursorPos(1,3)
  write("z: "..z.."")

  term.setCursorPos(1,4)
  write("y: "..y.."")

  term.setCursorPos(1,5)
  write("Cardinal direction: "..CardinalPoint(f).." ("..f..")")

  term.setCursorPos(1,6)

  input = read()
  if input == "no" then
    AskForCoordinate()
  else
    ClearScreen()
    write("Nice!")
    FirstMonitorScreen()
  end

  OriginX = x
  OriginY = y
  OriginZ = z
  OriginF = f

end

function CardinalPoint(f)
  if tostring(f) == "0" then
    return "south"
  elseif tostring(f) == "1" then
    return "west"
  elseif tostring(f) == "2" then
    return "north"
  elseif tostring(f) == "3" then
    return "east"
  else
    return "INVALID"
  end
end

function ClearMonitor()
  sleep(.1)
  rednet.send(tonumber(ComputerID), "clear()")
  sleep(.1)
end

function OpenConnection()
  rednet.open("left")
end

function DetermineBlocksToBeMined()
	BlocksToBeMined = tonumber(DigX) * tonumber(DigZ) * tonumber(OriginY)
end

function UpdateMonitor()

  message = ""

  message = message.."SCP(13,2);"..getFuelLevel().."   ;"

  message = message.."SCP(4,3);"..x.."  ;"

  message = message.."SCP(4,4);"..z.."  ;"

  message = message.."SCP(4,5);"..y.."  ;"

  message = message.."SCP(21,6);"..CardinalPoint(f).." ("..f..") ;"

  message = message.."SCP(21,7);"..BlocksToBeMined.."   ;"

  message = message.."SCP(15,8);"..BlocksMined..", "..BlocksMinedPercent.."%    ;"

  rednet.send(tonumber(ComputerID), message)

end

function FirstMonitorScreen()

-- ";" for the end of a message
-- "_" for the next line, with ";" so "_;" !

  ClearMonitor()

  message = ""

  message = message.."Name: "..TurtleLabel..", ID: "..TurtleID..";_;"

  message = message.."Fuel Level: "..getFuelLevel()..";_;"

  message = message.."x: "..x..";_;"

  message = message.."z: "..z..";_;"

  message = message.."y: "..y..";_;"

  message = message.."Cardinal direction: "..CardinalPoint(f).." ("..f..");_;"

  message = message.."Blocks to be mined: "..BlocksToBeMined..";_;"

  message = message.."Blocks mined: "..BlocksMined..";_;"

  rednet.send(tonumber(ComputerID), message)

end

function getFuelLevel()
  fuelLevel = turtle.getFuelLevel()
  return fuelLevel
end

function MoveForward()



	if turtle.forward() then

	ErrorMovingCount = 0

		if tonumber(f) == tonumber(0) then
			z = z + 1
		elseif tonumber(f) == tonumber(1) then
			x = x - 1
		elseif tonumber(f) == tonumber(2) then
			z = z - 1
		elseif tonumber(f) == tonumber(3) then
			x = x + 1
		end

	 else
		print("cannot move for: "..ErrorMovingCount)
		turtle.attack()
		MoveForward()
		ErrorMovingCount = ErrorMovingCount + 1
	end

  UpdateMonitor()

end

function digDown()
	turtle.digDown()
	BlocksMined = BlocksMined + 1
	MoveDown()
	InventoryManagement()
end

function digForward()
	turtle.dig()
  	BlocksMined = BlocksMined + 1
	MoveForward()
	InventoryManagement()
end

function digUp()
	turtle.digUp()
	BlocksMined = BlocksMined + 1
	MoveDown()
	InventoryManagement()
end

function MoveUp()
  turtle.up()
  y = y + 1
  UpdateMonitor()
end

function MoveDown()
  turtle.down()
  y = y - 1
  UpdateMonitor()
end

function TurnRight()

  turtle.turnRight()
  if tonumber(f) == tonumber(3) then
    f = 0
  else
    f = f + 1
  end

  UpdateMonitor()

end

function TurnLeft()

  turtle.turnLeft()
  if f == 0 then
    f = 3
  else
    f = f - 1
  end

  UpdateMonitor()

end

function InventoryManagement()

local freeSlots = 0

  if turtle.getItemCount(16) ~= 0 then

	-- Drop unwanted blocks set in slot 1
	for i = 3, 16 do
		turtle.select(i)
		if turtle.compareTo(1) then
			turtle.drop()
		end
	end

	-- Drop unwanted blocks set in slot 2
	for i = 3, 16 do
		turtle.select(i)
		if turtle.compareTo(2) then
			turtle.drop()
		end
	end

	for i = 1, 2 do
		turtle.select(i)
		turtle.drop(tonumber(turtle.getItemCount((i)) - tonumber(1)))
	end

	end

	-- -- Rearrange the Inventory
		-- --Get number of free slots
		-- for i = 3, 16 do
			-- if tonumber(turtle.getItemCount(i)) == tonumber(0) then
				-- freeSlots = freeSlots + 1
			-- end
		-- end

		-- turtle.select(16)
		-- for i = 3, 15 do
			-- if turtle.transferTo(i) then
				-- break
			-- end
		-- end






		-- setzen auf startposition
		turtle.select(1)


	if turtle.getItemCount(16) ~= 0 then
		GoToChest()
		EmptyTurtle()
		GoBackToMining()
	end


end

function EmptyTurtle()

	for o = 1, 2 do
		turtle.select(o)
		turtle.drop(tonumber(turtle.getItemCount(o)) - tonumber(1))
	end

	for i = 3, 16 do
		turtle.select(i)
		turtle.drop()
	end
	turtle.select(1)
end

function GoBackToMining()

	print("X: "..GoBackToX.."  Z: "..GoBackToZ)

	TurnLeft()
	TurnLeft()

	if tonumber(GoBackToZ) > 0 then
		for i = 1, GoBackToZ do
			MoveForward()
		end
	end

	TurnRight()

	if tonumber(GoBackToX) > 0 then
		for i = 1, GoBackToX do
			MoveForward()
		end
	end

	if tonumber(GoBackToY) > 0 then
		for i = 1, GoBackToY do
			MoveDown()
		end
	end

	while tonumber(f) ~= tonumber(GoBackToF) do
    TurnRight()
  end

	GoBackToX = 0
	GoBackToY = 0
	GoBackToZ = 0

end

function OppositeDirection(Direction)
	if tonumber(Direction) == tonumber(0) then
		return "2"
	elseif tonumber(Direction) == tonumber(1) then
		return "3"
	elseif tonumber(Direction) == tonumber(2) then
		return "0"
elseif tonumber(Direction) == tonumber(3) then
		return "1"
	end
end

function GoToChest()

GoBackToF = f

  -- Y-Richtung
  while tonumber(y) ~= tonumber(OriginY) do
    MoveUp()
	GoBackToY = GoBackToY + 1
  end


  -- X-Richtung


  if tonumber(x) ~= tonumber(OriginX) then
--print("x: "..x.."; OriginalX"..OriginX.."f: "..f.."; OriginalF: "..OriginF)
    if tonumber(x) <= tonumber(OriginX) then

      while tonumber(f) ~= tonumber(3) do
        TurnRight()
      end
    elseif tonumber(x) >= tonumber(OriginX) then

      while tonumber(f) ~= tonumber(1) do
        TurnRight()
      end
    end
  end

  while tonumber(x) ~= tonumber(OriginX) do
    MoveForward()
	GoBackToX = GoBackToX + 1
-- print("x: "..x.."; OriginalX"..OriginX.."f: "..f.."; OriginalF: "..OriginF)
  end


  -- Z-Richtung

  if tonumber(z) ~= tonumber(OriginZ) then
-- print("x: "..z.."; OriginalX"..OriginZ.."f: "..f.."; OriginalF: "..OriginF)
    if tonumber(z) <= tonumber(OriginZ) then

      while tonumber(f) ~= tonumber(0) do
        TurnRight()
      end
    elseif tonumber(z) >= tonumber(OriginZ) then

      while tonumber(f) ~= tonumber(2) do
        TurnRight()
      end
    end
  end

  while tonumber(z) ~= tonumber(OriginZ) do
    MoveForward()
	GoBackToZ = GoBackToZ + 1
-- print("x: "..z.."; OriginalX"..OriginZ.."f: "..f.."; OriginalF: "..OriginF)
  end

-- print("f: "..f.."Opposite: "..OppositeDirection(OriginF))






 while tonumber(f) ~= tonumber(OppositeDirection(OriginF)) do

	TurnLeft()

	print("f: "..f.."Opposite: "..OppositeDirection(OriginF))
end

end

function CurveRight()
  TurnRight()
  digForward()
  TurnRight()
end

function CurveLeft()
  TurnLeft()
  digForward()
  TurnLeft()
end

function ExcavateOneLayer()

CurveDirection = "right"

for o = 2, DigZ do
for i = 2, DigX do
digForward()
end

if CurveDirection == "right" then
	CurveRight()
	CurveDirection = "left"
elseif CurveDirection == "left" then
	CurveLeft()
	CurveDirection = "right"
end

end

for i = 2, DigX do
digForward()
end



if CurveDirection == "right" then
	TurnLeft()
	for p = 2, DigZ do
	MoveForward()
	end
TurnLeft()

for p = 2, DigX do
	MoveForward()
end
TurnLeft()
TurnLeft()

elseif CurveDirection == "left" then
	TurnRight()

	for p = 2, DigZ do
		MoveForward()
	end
	TurnRight()
end


end

function DigToBedrock()

  while true do

    if tonumber(y) == tonumber(1) then
      break
    end

    ExcavateOneLayer()

    digDown()
  end

  ExcavateOneLayer()
  GoToChest()
EmptyTurtle()
end





setVariables()
OpenConnection()
FirstScreen()
AskForCoordinate()
getFuelLevel()
AskForDimension()
DetermineBlocksToBeMined()
FirstMonitorScreen()
DigToBedrock()




write("finished!")