Turtle flat builder v1

local lastSlot = 1
local fuelSlot = 16
local function refuelIfNeeded()
    if turtle.getFuelLevel() < 10 then
        turtle.select(fuelSlot)
        turtle.refuel(1)
        return
    end
end

-- Function to check if there is a block to the left of the turtle
local function checkLeft()
    turtle.turnLeft()
    local success = turtle.detect()
    turtle.turnRight()
    return success
end

-- Function to place a block in the previous position of the turtle
local function placeBlock()
    turtle.select(lastSlot)
    if turtle.getItemCount(lastSlot) > 0 then
        turtle.place()
    else
        for slot = 1, 15 do
            if turtle.getItemCount(slot) > 0 then
                lastSlot = slot
                turtle.select(slot)
                turtle.place()
                return
            end
        end
    end
end

-- Main function to move backwards and place a block
local function moveBackwardsAndPlace()
    refuelIfNeeded()
    if checkLeft() then
        if turtle.back() then
            placeBlock()
        else
            turtle.turnLeft()
        end
    else
        turtle.turnRight()
        turtle.back()
        placeBlock()
    end
end

local function inventoryNotEmpty()
    local blockFound = false

    for slot = 1, 15 do
        if turtle.getItemCount(slot) > 0 then
            blockFound = true
            break
        end
    end
    return blockFound
end

-- Main loop to repeat the movement and block placement
while true do
    if inventoryNotEmpty() then
        moveBackwardsAndPlace()
    else
        turtle.suckUp(64)
        os.sleep(1)
    end
end