excavateb

local size = 10
local currentPosition   = {x = 0, y = 0, z =0, d  = 0}
local savePostion       = {x = 0, y = 0, z =0, d  = 0}
local homePosition      = {x = 0, y = 0, z =0, d  = 0}
x, y, z, d = 0, 0, 0, 0

-- dig
function excavate(size, depth)
    local isFinished = false
    local useDepth = depth ~= nil and depth > 0
    local depthCount = 0

    if useDepth then
        if startNextLevel() then
            depthCount = depthCount + 1
            isFinished = depth >= depthCount
        end
    else
        isFinished = startNextLevel()
    end

    while isFinished do
        --up and down or column
        for i = 0, size - 1 do
            --row or left to right
            for j = 0, size - 1 do
                dig("forward")
                go("forward")
            end
            if i ~= size - 1 then
                --even turns right
                if i % 2 == 0 then
                    turn("right")
                    dig("forward")
                    go("forward")
                    turn("right")
                --odd turns left
                else
                    turn("left")
                    dig("forward")
                    go("forward")
                    turn("left")
                end
            end
        end
        if size % 2 == 1 then --if the size is odd  180 if not 900
            turn("left")
            turn("left")
        else
            turn("left")
        end
        if useDepth then
            if startNextLevel() then
                depthCount = depthCount + 1
                isFinished = depth >= depthCount
            end
        else
            isFinished = startNextLevel()
        end
    end

    local function startNextLevel()
        local atNext = go("down")
        if not atNext then
            dig("down")
            atNext = go("down")
        end
        return atNext
    end
end

function dig(str)
    local success = false
    if string.lower(str) == "forward" or string.lower(str) == "f" then
        success = turtle.dig()
    elseif string.lower(str) == "up" or string.lower(str) == "u" then
        success = turtle.digUp()
    elseif string.lower(str) == "down" or string.lower(str) == "down" then
        success = turtle.digDown()
    end
    return success
end

--check fuel
function checkfuel()
end

function go(str)
    local success = false
    if string.lower(str) == "down" or string.lower(str) == "d" then
        if turtle.down() then
            currentPosition["y"] = currentPosition["y"] - 1
            success = true
        else
            term.write("I'm stuck!")
        end
    end
    if string.lower(str) == "up" or string.lower(str) == "u" then
        currentPosition["y"] = currentPosition["y"] + 1
        success = true
    end
    if string.lower(str) == "forward" or sting.lower(str) == "f" then
        if d == 0 then  currentPosition["z"] = currentPosition["z"] + 1 end
        if d == 1 then  currentPosition["x"] = currentPosition["x"] - 1 end
        if d == 2 then  currentPosition["z"] = currentPosition["z"] - 1 end
        if d == 3 then  currentPosition["x"] = currentPosition["x"] + 1 end
        success = true
    end
    if string.lower(str) == "back" or string.lower(str) == "b" then
        if d == 0 then currentPosition["z"] = currentPosition["z"] - 1 end
        if d == 1 then currentPosition["x"] = currentPosition["x"] + 1 end
        if d == 2 then currentPosition["z"] = currentPosition["z"] + 1 end
        if d == 3 then currentPosition["x"] = currentPosition["x"] - 1 end
        success = true
    end
    return success
end

function turn(str)
    if string.lower(str) == "right" or string.lower(str) == "r" then
        turtle.turnright()
        currentPosition["d"] = (currentPosition["d"] + 1) % 4
    end
    if string.lower(str) == "left" or string.lower(str) == "l" then
        turtle.turnleft()
        currentPosition["d"] = (currentPosition["d"] - 1) % 4
    end
end

-- track positon
function trackPosition()
end

--track Inventory
function trackInventory()
end

function goToPosition(position, order, canDig)
    local isFinished = false
    if order == nil then order = {"x", "z", "y"} end
    if canDig == nil then canDig = false end
end

excavate(size,depth)