Not-So-Simple Turtle Quarry

length = 5
width = 5
depth = 5
--put unwanted item (eg. cobblestone) in slot 16
-----------

facing = 0 --relative, 0=north, 1=east, etc
x, y, z = 0, 0, 0

moveState = 0

width = width - 1

function output(x, y, z, facing)
    term.clear()
    term.setCursorPos(1,1)
    print("X Position: "..x)
    print("Y Position: "..y)
    print("Z Position: "..z)
    print("Facing: "..facing)
end



function left(amount, facing)
    for i=1, amount do
        turtle.turnLeft()
        facing = facing - 1
        if (facing == -1) then
            facing = 3
        end
    end
    return facing
end

function right(amount, facing)
    for i=1, amount do
        turtle.turnRight()
        facing = facing + 1
        if (facing == 4) then
            facing = 0
        end
    end
    return facing
end

function dig(direction, distance, dig, attack, drop, x, y, z, facing)
    --direction 0 = forward, 1 up, -1 down
    output(x, y, z, facing)
    x = x or false
    y = y or false
    z = z or false
    dig = dig or false
    attack = attack or false
    drop = drop or false

    for i=1, distance do
        if (direction == 0) then
            while (turtle.forward() == false) do
                if (dig == true) then
                    turtle.dig()
                end
                if (attack == true) then
                    turtle.attack()
                end
            end
            if (facing == 0) then
                z = z + 1
            elseif (facing == 1) then
                x = x + 1
            elseif (facing == 2) then
                z = z - 1
            elseif (facing == 3) then
                x = x - 1
            end
            output(x, y, z, facing)
        end
        if (direction == -1) then
            while (turtle.down() == false) do
                if (dig == true) then
                    turtle.digDown()
                end
                if (attack == true) then
                    turtle.attackDown()
                end
            end
            y = y - 1
            output(x, y, z, facing)
        end
        if (direction == 1) then
            while (turtle.up() == false) do
                if (dig == true) then
                    turtle.digUp()
                end
                if (attack == true) then
                    turtle.attackUp()
                end
            end
            y = y + 1
            output(x, y, z, facing)
        end
        if (turtle.getItemCount(15) > 0 and drop == true) then
            for i=1, 15 do
                turtle.select(i)
                if (turtle.compareTo(16) == true) then
                    turtle.drop()
                    turtle.select(15)
                    turtle.transferTo(i)
                end
            end
            turtle.select(1)

            if (turtle.getItemCount(15) > 0) then
                deposit(x, y, z, facing)
            end
        end
    end
    return x, y, z
end

function deposit(x, y, z, facing, finished)
    finished = finished or false

    oldDir = facing

    output(x, y, z, facing)

    for i=1, -y do
        while (turtle.up() == false) do
            turtle.attackUp()
        end
    end
    while (facing ~= 1) do
        facing = right(1, facing)
    end
    for i=1, -x do
        while (turtle.forward() == false) do
            turtle.attack()
        end
    end
    facing = right(1, facing)
    for i=1, z do
        while (turtle.forward() == false) do
            turtle.attack()
        end
    end

    for i=1, 15 do
        turtle.select(i)
        turtle.drop()
    end
    turtle.select(1)

    if (finished == false) then
        facing = right(2, facing)

        for i=1, z do
            while (turtle.forward() == false) do
                turtle.attack()
            end
        end

        facing = left(1, facing)

        for i=1, -x do
            while (turtle.forward() == false) do
                turtle.attack()
            end
        end
        for i=1, -y do
            while (turtle.down() == false) do
                turtle.attackDown()
            end
        end

        while (facing ~= oldDir) do
            facing = right(1, facing)
        end
    end
end


for d=1, depth do
    for l=1, length do
        if (moveState % 2 == 0) then
            facing = left(1, facing)
            x, y, z = dig(0, width, true, true, true, x, y, z, facing)
            facing = right(1, facing)
            if (l ~= length) then
                x, y, z = dig(0, 1, true, true, true, x, y, z, facing)
            end
        end
        if (moveState % 2 == 1) then
            facing = right(1, facing)
            x, y, z = dig(0, width, true, true, true, x, y, z, facing)
            facing = left(1, facing)
            if (l ~= length) then
                x, y, z = dig(0, 1, true, true, true, x, y, z, facing)
            end
        end
        moveState = moveState + 1
    end
    facing = right(2, facing)
    if (d ~= depth) then
        x, y, z = dig(-1, 1, true, true, true, x, y, z, facing)
    end
    moveState = moveState + 1
end

deposit(x, y, z, facing, true)

term.clear()
term.setCursorPos(1,1)

print("Done!")