turtle stairwell

--- PATHING VARS
local pos = vector.new(0,0,0)
local tPos = vector.new(0,0,0)
local facing = 0 -- 0: north (-Z), 1: east (+X), 2: south (+Z): 3: west (-X)
local sleepTime = 0.8

--- MINING VARS
local width = 3
local length = 3
local depth = 4

--- MOVEMENT FUNCS
function moveForward()
    local couldMove, moveReason = turtle.forward()
    if(couldMove == false) then
        print(moveReason)
        return false
    end

    if(facing == 0) then
        pos = pos + vector.new(0,0,-1)
    end
    if(facing == 1) then
        pos = pos + vector.new(1,0,0)
    end
    if(facing == 2) then
        pos = pos + vector.new(0,0,1)
    end
    if(facing == 3) then
        pos = pos + vector.new(-1,0,0)
    end

    print(pos)
    return true
end

function moveUp()
    local couldMove, moveReason = turtle.up()
    if(couldMove == false) then
        print(moveReason)
        return false
    end
    pos = pos + vector.new(0,1,0)
    print(pos)
    return true
end

function moveDown()
    local couldMove, moveReason = turtle.down()
    if(couldMove == false) then
        print(moveReason)
        return false
    end
    pos = pos + vector.new(0,-1,0)
    print(pos)
    return true
end

--- MOVEMENT / DIG FUNCS

function tryDig()
    --detect if solid block
    if(turtle.detect()) then
        --try dig
        local couldDig, digReason = turtle.dig()
        if(couldDig == false) then
            --print(digReason)
            return false
        end
        return true
    end
    return true
end

function tryDigAndMoveDown()
    if(turtle.detectDown()) then
        local couldDig, digReason = turtle.digDown()
        if(couldDig == false) then
            print(digReason)
        end
    end
    moveDown()
end

function tryDigAndMoveUp()
    if(turtle.detectUp()) then
        local couldDig, digReason = turtle.digUp()
        if(couldDig == false) then
            print(digReason)
        end
    end
    moveUp()
end

function tryDigAndMove()
    tryDig()
    moveForward()
end

--- TURNING FUNCS

function turnRight()
    sleep(sleepTime/2)
    if(facing == 3) then
        facing = 0
        turtle.turnRight()
        print("facing: " .. facing)
        return
    end
    facing = facing + 1
    turtle.turnRight()
    print("facing: " .. facing)

end

function turnLeft()
    sleep(sleepTime/2)
    if(facing == 0) then
        facing = 3
        turtle.turnLeft()
        print("facing: " .. facing)
        return
    end
    facing = facing - 1
    turtle.turnLeft()
    print("facing: " .. facing)
end

function faceNorth()
    print("TRY NORTH")
    if(facing == 0) then
        return
    end
    if(facing == 1) then
        turnLeft()
        return
    end
    if(facing == 2) then
        turnLeft()
        sleep(sleepTime)
        turnLeft()
        return
    end
    if(facing == 3) then
        turnRight()
        return
    end
end

function faceEast()
    print("TRY EAST")
    if(facing == 0) then
        turnRight()
        return
    end
    if(facing == 1) then
        return
    end
    if(facing == 2) then
        turnLeft()
        return
    end
    if(facing == 3) then
        turnLeft()
        sleep(sleepTime)
        turnLeft()
        return
    end
end

function faceSouth()
    print("TRY SOUTH")
    if(facing == 0) then
        turnRight()
        sleep(sleepTime)
        turnRight()
        return
    end
    if(facing == 1) then
        turnRight()
        return
    end
    if(facing == 2) then
        return
    end
    if(facing == 3) then
        turnLeft()
        return
    end
end

function faceWest()
    print("TRY WEST")
    if(facing == 0) then
        turnLeft()
        return
    end
    if(facing == 1) then
        turnLeft()
        sleep(sleepTime)
        turnLeft()
        return
    end
    if(facing == 2) then
        turnRight()
    end
    if(facing == 3) then
        return
    end
end
--- MISC

function printPos()
    write("- POS: ")
    print(pos)
end

function printTPos()
    write("- TARGET POS: ")
    print(tPos)
end
--- GOTO
function matchY()
    if(pos.y > tPos.y) then
        for y = 1, math.abs(tPos.y-pos.y), 1 do
            moveDown()
            sleep(sleepTime/2)
        end
    end

    if(pos.y < tPos.y) then
        for y = 1, math.abs(tPos.y-pos.y), 1 do
            moveUp()
            sleep(sleepTime/2)
        end
    end
end

function matchX()
    if(pos.x > tPos.x) then
        faceWest()
        for y = 1, math.abs(tPos.x-pos.x), 1 do
            moveForward()
            sleep(sleepTime/2)
        end
    end

    if(pos.x < tPos.x) then
        faceEast()
        for y = 1, math.abs(tPos.x-pos.x), 1 do
            moveForward()
            sleep(sleepTime/2)
        end
    end
end

function matchZ()
    if(pos.z > tPos.z) then
        faceNorth()
        for y = 1, math.abs(tPos.z-pos.z), 1 do
            moveForward()
            sleep(sleepTime/2)
        end
    end

    if(pos.z < tPos.z) then
        faceSouth()
        for y = 1, math.abs(tPos.z-pos.z), 1 do
            moveForward()
            sleep(sleepTime/2)
        end
    end
end
--- MAIN USER INPUT


write("Starting from right of this block, the depth of the quarry (X): ")
depth = read()

write("Width of the quarry (X): ")
width = read()

--- MAIN PREMINING CHECKS
local fuelLevel = turtle.getFuelLevel()
print("Fuel level: ".. fuelLevel)

if(fuelLevel <= 1000) then
    --select slot 16, used for fuel
    turtle.select(16)

    print(textutils.serialise(turtle.getItemDetail()))

    local ok, err = turtle.refuel()
    if ok then
        local newFuellevel = turtle.getFuelLevel()
        print(("Refuelled %d, current level is %d"):format(newFuellevel - fuelLevel, newFuellevel))
    else
        printError(err)
    end
end
turtle.select(1)

-- MAIN MOVEMENT

-- dig down, then dig front twice, repeat

local invertTurn = -1


for z = 0,depth,1 do
    turtle.digDown()
    turtle.down()
    --
    if(turtle.detectDown() == false) then
        turtle.select(1)
        turtle.placeDown()
    end
    --
    tryDigAndMove()
    turtle.digUp()
    turtle.turnRight()
end