Farm Builder

DIRT = "minecraft:dirt"
COBBLE = "minecraft:cobblestone"
GLOWSTONE = "minecraft:glowstone"

local function place(block, direction)
    local currentDetail = turtle.getItemDetail()
    if not currentDetail or currentDetail.name ~= block then
        while true do
            local didFind = false
            for i = 1, 16 do
                local nextDetail = turtle.getItemDetail(i)
                if nextDetail and nextDetail.name == block then
                    didFind = true
                    turtle.select(i)
                    break
                end
            end
            if didFind then
                break
            else
                print("Need more " .. block)
                print("Press any key...")
                os.pullEvent("key")
            end
        end
    end
    turtle.placeDown()
end

local doPlace = function(isWater, z)
    place(isWater and (z % 7 == 4 and GLOWSTONE or COBBLE) or DIRT)
end
local X_LIMIT, Y_LIMIT, Z_LIMIT = 14, 12, 33
for y = 1, Y_LIMIT do
    for x = 1, X_LIMIT do
        local isWater = x == 4 or x == 11
        if isWater then
            turtle.down()
        end
        for z = 1, Z_LIMIT do
            doPlace(isWater, z)
            turtle.forward()
        end
        if x ~= X_LIMIT then
            local turn = (x % 2 ~= y % 2) and turtle.turnLeft or turtle.turnRight
            turn()
            doPlace(isWater, 1)
            turtle.forward()
            turn()
            if isWater then
                turtle.up()
            end
        else
            if isWater then
                turtle.up()
            end
            turtle.turnLeft()
            turtle.turnLeft()
            place(isWater and COBBLE or DIRT)
            turtle.up()
            turtle.up()
            turtle.up()
        end
    end
end