Water Mill Placer v1.1

--
--              Water Mill Placer v1.1 by Joseph Jones
--
--              Instructions found at: http://www.computercraft.info/forums2/index.php?/topic/13920-water-mill-placer/
--
--              Needs X watermills.             Uses slot 1
--              Needs X/2 cables.               Uses slot 2
--              Needs some building material.   Uses slot 3-12
--              Needs 3 water buckets.          Uses slot 13-15
--              Needs fuel.                     Uses slot 16
--
--              ChangeLog:
--                      June 29, 2013: [v1.0] Finished initial release
--          July  7, 2013: [v1.1] Fixed issue where turtle can run out of fuel moving backwards
--

local currSlot = 3
local waterSlot = 13
local direction

function checkFuel()
        if(turtle.getFuelLevel() < 2) then
                turtle.select(16)
                if(turtle.refuel(1)==false) then
                        print("Turtle needs more fuel in slot 16. Press enter to continue")
                        io.read()
                        checkFuel()
                end

                turtle.select(currSlot)
        end
end

function moveUp()
        checkFuel()
        while(turtle.up()==false)do turtle.digUp() end
end

function moveDown()
        checkFuel()
        while(turtle.down()==false)do turtle.digDown() end
end

function move()
        checkFuel()
        while(turtle.forward()==false)do turtle.dig() end
end

function back()
    checkFuel()
        while(turtle.back()==false)do end
end

function placeGround()

        local lastSlot = currSlot
        while(turtle.getItemCount(currSlot)==0)do
                currSlot = currSlot+1
                if(currSlot == 13) then
                        currSlot = 3
                end
                if(currSlot == lastSlot) then
                        print("Turtle needs more material in slot 3-12.")
                        print("Press enter to continue")
                        io.read()
                end
                turtle.select(currSlot)
        end

        turtle.placeDown()
end

function placeWaterMill()
        turtle.select(1)
        while(turtle.getItemCount(1)==0)do
                print("Turtle needs more watermills in slot 1.")
                print("Press enter to continue")
                io.read()
        end
        if(turtle.compareDown()==false) then
                while(turtle.placeDown()==false) do turtle.digDown() end
        end
        turtle.select(currSlot)
end

function placeCable()
        turtle.select(2)
        while(turtle.getItemCount(2)==0)do
                print("Turtle needs more cables in slot 2.")
                print("Press enter to continue")
                io.read()
        end
        if(turtle.compareDown()==false) then
                while(turtle.placeDown()==false) do turtle.digDown() end
        end
        turtle.select(currSlot)
end

function placeWater()
        turtle.select(waterSlot)

        if(waterSlot<15) then
                waterSlot = waterSlot+1
        end

        turnOpposite()
        turtle.place()
        turn()
        turtle.select(currSlot)

end

function turn()
        if(direction==0) then
                turtle.turnLeft()
        else if(direction==1) then
                turtle.turnRight()
        end end
end

function turnOpposite()
        if(direction==1) then
                turtle.turnLeft()
        else if(direction==0) then
                turtle.turnRight()
        end end
end

function changeDirection()
        if(direction==1) then
                direction=0
        else
                direction=1
        end
end

function quarry(LENGTH, layer)
        turtle.select(currSlot)
        placeGround()
        turtle.turnRight()
        local length = LENGTH
        direction = 0

        while(length>0) do
                local width= 4

                while(width>0) do
                        move()
                        width= width- 1


                        if(layer==1) then
                                if(length>1) then
                                        if(length==LENGTH) then
                                                placeGround()
                                        else if(width==3) then
                                                placeWaterMill()
                                        else if(width==1) then
                                                placeWaterMill()
                                        else if(width==2) then
                                                placeCable()
                                        else placeGround()
                                        end end end end
                                else
                                        placeGround()
                                end
                        else
                                if(length>1) then
                                        if(length==LENGTH) then
                                                placeGround()
                                                turtle.digUp()
                                        else if(width==3) then
                                                placeGround()
                                        else if(width==1) then
                                                placeGround()
                                        else if(width==2) then
                                                placeGround()
                                        else
                                                placeGround()
                                                turtle.digUp()
                                        end end end end
                                else
                                        placeGround()
                                        turtle.digUp()
                                end
                        end


                        if(length == LENGTH) then
                                if(width==1) then
                                        turtle.turnRight()
                                        placeWater()
                                        turtle.turnLeft()
                                end
                                if(width==3) then
                                        turtle.turnRight()
                                        placeWater()
                                        turtle.turnLeft()
                                end
                        else
                                if(width==3) then
                                        if(direction==1) then
                                                placeWater()
                                        else
                                                turnOpposite()
                                                placeWater()
                                                turn()
                                        end
                                end
                        end
                end

                length = length - 1

                if(length>0) then
                        turn()
                        move()
                        if(layer==2) then turtle.digUp() end
                        placeGround()
                        if(length == LENGTH-1) then
                                changeDirection()
                                turtle.turnLeft()
                                placeWater()
                        else
                                turn()
                                changeDirection()
                        end

                end
        end


end

function placeLine(LENGTH)
        local length = LENGTH - 1

        while(length>0) do
                placeGround()
                move()
                length = length - 1
        end

end

function boarder(LENGTH)
        local height = 4
        moveDown()
        moveDown()
        moveDown()
        while(height>0) do
                placeLine(LENGTH+2)
                turtle.turnRight()
                placeLine(7)
                turtle.turnRight()
                placeLine(LENGTH+2)
                turtle.turnRight()
                placeLine(7)
                turtle.turnRight()
                height = height - 1
                if(height>0) then moveUp() end
        end

        turtle.turnRight()
        move()
        turtle.turnLeft()
        move()
end

function main()

        local input
        local lenth
        local wantsBoarder

        print("Want a boarder? ")
        input = io.read()
        while((input ~= 'n') and (input ~= 'N') and (input ~= 'Y') and (input ~= 'y'))do
                print("Y or N: ")
                input = io.read()
        end
        wantsBoarder = input

        print("Length: ")
        input = tonumber(io.read())
        while(input<3 or input > 34) do
                print("The length must be between 3-34: ")
                input = tonumber(io.read())
        end
        length = input

        if(wantsBoarder=='Y' or wantsBoarder =='y') then
                boarder(length)
        end

        turtle.select(currSlot)
        moveDown()
        quarry(length,1)
        if(direction==1) then
                back()
                turtle.select(15)
                turtle.place()
                back()
                back()
                back()
                turnOpposite()
        else
                turnOpposite()
        end
        waterSlot = 13
        turtle.select(13)
        turtle.place()
        os.sleep(.60)
        turtle.select(14)
        turtle.place()
        os.sleep(.60)
        turtle.select(15)
        turtle.place()
        moveDown()
        os.sleep(.60)
        moveDown()
        quarry(length,2)

        turtle.select(15)
        os.sleep(.20)
        if(direction==0) then
                turnOpposite()
                turtle.place()
        end
        moveUp()
        moveUp()
        moveUp()
        turtle.placeDown()
        if(direction==1) then
                back()
                back()
                back()
                back()
                turtle.turnLeft()
        end
end

main()