--[[VARIABLES]]--

local mineHeight = 0;
local run = true;
local currentRotation = 0
local currentYPosition = 0
local currentZPosition = 0

local oldYPosition = 0
local oldZPosition = 0
local oldRotation = 0



--[[BASIC FUNCTIONS]]--

function updateScreen()
    term.clear()
    term.setCursorPos(1, 1)
    print("LOGAN'S MINING SYSTEM")
    print("Y: " .. currentYPosition)
    print("Z: " .. currentZPosition)
    print("ROTATION: " .. currentRotation)
    print("FUEL: " .. turtle.getFuelLevel() .. " / " .. turtle.getFuelLimit())
    print("OLD Y POSTIION: " .. oldYPosition)
    print("OLD Z POSITION: " .. oldZPosition)
end


function turnLeft()
    currentRotation = currentRotation - 1;
    turtle.turnLeft()
end


function turnRight()
    currentRotation = currentRotation + 1;
    turtle.turnRight()
end


function dig()
    updateScreen()

    if turtle.getItemCount(16) == 0 then
        turtle.dig()
    else
        returnToHome()
        deposit()
        returnToOldPosition()
        turtle.dig()
    end
end


function digUp()
    updateScreen()

    if turtle.getItemCount(16) == 0 then
        turtle.digUp()
    else
        returnToHome()
        deposit()
        returnToOldPosition()
    end
end


function digDown()
    updateScreen()

    if turtle.getItemCount(16) == 0 then
        turtle.digDown()
    else
        returnToHome()
        deposit()
        returnToOldPosition()
    end
end


function deposit()
    for i = 1, 16 do
        turtle.select(i)
        turtle.drop()
    end

    turtle.select(1)
end


function forward()
    updateScreen()

    turtle.forward()

    if currentRotation == 0 then
        currentZPosition = currentZPosition + 1
    elseif currentRotation ==  1 then
        currentXPosition = currentXPosition + 1
    elseif currentRotation == -1 then
        currentXPosition = currentXPosition - 1
    else
        currentZPosition = currentZPosition - 1
    end
end


--[[MOVEMENT ACTIONS]]--

function oddLevelDig()
    dig()
    turnRight()
    dig()
    turnRight()
    dig()
end


function evenLevelDig()
    dig()
    turnLeft()
    dig()
    turnLeft()
    dig()
end


function turnStraight()
    if currentRotation > 0 then
        repeat
            turnLeft()
        until currentRotation == 0
    else
        repeat
            turnRight()
        until currentRotation == 0
    end
end


function turnBackwards()
    if currentRotation > 0 then
        repeat
            turnRight()
        until currentRotation == 2
    else
        repeat
            turnLeft()
        until currentRotation == -2
    end
end


function returnToHome()
    oldRotation = currentRotation
    oldYPosition = currentYPosition
    oldZPosition = currentZPosition

    turnBackwards()

    repeat
        forward()
    until currentZPosition == 0

    for i = 1, currentYPosition do
        turtle.down()
    end
end


function returnToOldPosition()
    turnStraight()

    repeat
        forward()
    until currentZPosition == oldZPosition

    for i = 1, currentYPosition do
        turtle.up()
    end

    if oldRotation == -1 then
        turnLeft()
    else
        turnRight()
    end
end



write("Mine Height: ")
mineHeight = tonumber(read());

turtle.select(1)
turtle.refuel()



while run do
    turnLeft()

    for i = 1, mineHeight do
        if i % 2 == 1 then
            oddLevelDig()
        else
            evenLevelDig()
        end

        if i ~= mineHeight then
            digUp()
            turtle.up()
            currentYPosition = currentYPosition + 1
        end
    end

    turnStraight()
    forward()
    turnLeft()

    for i = mineHeight, 1, -1 do
        if i % 2 == 1 then
            oddLevelDig()
        else
            evenLevelDig()
        end

        if i ~= 1 then
            digDown()
            turtle.down()
            currentYPosition = currentYPosition - 1
        end

    end

    turnStraight()
    forward()
end

--loadstring(http.get("https://pastebin.com/raw/EpEm4WZ3").readAll())()