Hallway Builder - Turtle - Computer Craft

-- Hallway Builder Program (Updated with Slots 2 and 3 for Wall Blocks)

-- Ensure the turtle has enough fuel
local function ensureFuel(needed)
    if turtle.getFuelLevel() < needed then
        print("Not enough fuel. Please refuel the turtle.")
        error()
    end
end

-- Check if the turtle can move forward
local function safeForward()
    while not turtle.forward() do
        if turtle.detect() then
            turtle.dig()
        else
            sleep(0.5)
        end
    end
end

-- Return to the starting position
local function returnToStart(steps)
    turtle.turnLeft()
    turtle.turnLeft()
    for i = 1, steps do
        safeForward()
    end
    turtle.turnLeft()
    turtle.turnLeft()
end

-- Select a slot containing wall blocks (Slots 2 and 3)
local function selectWallBlock()
    if turtle.getItemCount(2) > 0 then
        turtle.select(2)
    elseif turtle.getItemCount(3) > 0 then
        turtle.select(3)
    else
        print("Out of wall blocks!")
        error()
    end
end

-- Build the floor and first layer of walls
local function buildFirstLayer(length)
    for i = 1, length do
        -- Place floor block
        turtle.select(1)  -- Floor blocks
        turtle.placeDown()

        -- Place wall blocks to the left and right
        selectWallBlock()

        turtle.turnLeft()
        turtle.place()
        turtle.turnRight()

        turtle.turnRight()
        turtle.place()
        turtle.turnLeft()

        -- Move forward
        ensureFuel(1)
        safeForward()
    end
end

-- Build wall layers
local function buildWallLayer(length)
    for i = 1, length do
        selectWallBlock()

        turtle.turnLeft()
        turtle.place()
        turtle.turnRight()

        turtle.turnRight()
        turtle.place()
        turtle.turnLeft()

        -- Move forward
        ensureFuel(1)
        safeForward()
    end
end

-- Build the ceiling with half slabs
local function buildCeiling(length)
    for i = 1, length do
        selectWallBlock()

        turtle.turnLeft()
        turtle.place()
        turtle.turnRight()

        turtle.turnRight()
        turtle.place()
        turtle.turnLeft()

        -- Place ceiling half slab
        turtle.select(4)  -- Ceiling half slabs
        turtle.placeUp()

        -- Move forward
        ensureFuel(1)
        safeForward()
    end
end

-- Main Program
local hallwayLength = 20

-- Calculate required fuel
local totalMoves = hallwayLength * 6  -- Approximate total movements
ensureFuel(totalMoves)

-- Build the first layer (floor and bottom walls)
buildFirstLayer(hallwayLength)
returnToStart(hallwayLength)

-- Move up to the second layer
ensureFuel(1)
turtle.up()

-- Build the second layer of walls
buildWallLayer(hallwayLength)
returnToStart(hallwayLength)

-- Move up to the third layer
ensureFuel(1)
turtle.up()

-- Build the third layer of walls and the ceiling
buildCeiling(hallwayLength)
returnToStart(hallwayLength)

-- Move back down to the ground level
ensureFuel(2)
turtle.down()
turtle.down()

print("Hallway construction complete!")