local function checkBlock()
    isBlockDown, blockDown = turtle.inspectDown()

    if isBlockDown and (blockDown.name == "minecraft:wheat" or blockDown.name == "minecraft:carrots") and blockDown.state.age == 7 then
        turtle.digDown()
        turtle.suckDown()
    end

    if (blockDown.name == "minecraft:carrots") then
        turtle.select(3)
    else
        turtle.select(2)
    end
    turtle.placeDown()
end

local function refuel()
    turtle.select(16)

    if turtle.getFuelLevel() < 100 then
        --if turtle.getItemCount(1) < 8 then
            --turtle.turnLeft()
            --turtle.suck(56)
        --end

        turtle.refuel()
    end

    os.setComputerLabel("Farming. Fuel: "..turtle.getFuelLevel())
end

local function harvest()
 for i=1,4 do
        for j=1,6 do
            turtle.forward()
            checkBlock()
            refuel()
        end

        if i % 2 ~= 0 then
            turtle.turnRight()
            turtle.forward()
            checkBlock()
            turtle.turnRight()
        elseif i % 4 == 0 then
            turtle.turnLeft()
            turtle.forward()
            turtle.forward()
            turtle.turnLeft()
            checkBlock()
        else
            turtle.turnLeft()
            turtle.forward()
            turtle.turnLeft()
            checkBlock()
        end
    end
end

local function deposit()
    isBlock, block = turtle.inspectDown()

    if isBlock and block.name == "minecraft:chest" then
        for i=1,15 do
            turtle.select(i)

            item = turtle.getItemDetail()

            if item then
                count = item.count

                if i == 2 or i == 3 then
                    count = count - 4
                end

                if count > 0 then
                    turtle.dropDown(count)
                end
            end
        end
    end
end

local function main()
    while true do
        for i=1,2 do
            harvest()
        end

        turtle.back()
        turtle.turnLeft()

        for i=1,10 do
            turtle.forward()
        end

        turtle.turnRight()
        turtle.forward()

        deposit()

        for i=1,480 do
            os.setComputerLabel("Waiting "..480-i.." seconds")
            sleep(1)
        end
    end
end

main()