CC - Sand Miner

function select_fuel()
    local slot = 1
    local data

    while slot <= 16 do
        data = turtle.getItemDetail(slot)
        if data and (data.name == "minecraft:lava_bucket" or data.name == "minecraft:coal" or data.name == "minecraft:planks" or data.name == "minecraft:log") then
            turtle.select(slot)
            return true
        end
        slot = slot + 1
    end
    return false
end
function is_inventory_full()
    local slot = 1
    local data

    while slot <= 16 do
        data = turtle.getItemDetail(slot)
        if not data then
            return false
        end
        slot = slot + 1
    end
    return true
end
function check_fuel()
    if turtle.getFuelLevel() < 10 then
        while not select_fuel() do
            print("Waiting fuel. Retrying refuel in 10 seconds.")
            sleep(10)
        end
        turtle.refuel()
    end
end
function avance()
    local grav = 0
    local success, data

    while not turtle.forward() do
        success, data = turtle.inspect()
        check_fuel()
        if success then
            turtle.dig()
            if data.name == "minecraft:gravel" then
                grav = grav + 1
            end
        end
    end
    return grav
end
function recule()
    while not turtle.back() do
        check_fuel()
        turtle.turnLeft()
        turtle.turnLeft()
        turtle.dig()
        turtle.turnLeft()
        turtle.turnLeft()
    end
end
function dig_collumn(grav)
    local z, ntp = 0, 0

    while turtle.detectUp() or grav > 0 or ntp > 0 do
        check_fuel()
        while not turtle.up() do
            turtle.digUp()
            turtle.suckUp()
            ntp = ntp + 1
        end
        turtle.suckUp()
        z = z + 1
        if ntp > 0 then ntp = ntp - 1 end
        if grav > 0 then grav = grav - 1 end
    end
    turtle.suck()
    turtle.suckUp()
    while z > 0 do
        if not turtle.down() then
            check_fuel()
            turtle.digDown()
        end
        z = z - 1
    end
end
function stone_down()
    local success, data = turtle.inspectDown()
    if success and data.name ~= "minecraft:dirt" and data.name ~= "minecraft:grass" then
        return true
    elseif not turtle.detectDown() then
        return true
    end
    return false
end
function select_dirt()
    local i = 1
    local data

    while i < 16 do
        data = turtle.getItemDetail(i)
        if data and data.name == "minecraft:dirt" then
            turtle.select(i)
            return true
        end
        i = i + 1
    end
    return false
end
function replace_bloc_by_dirt()
    if select_dirt() then
        turtle.digDown()
        turtle.placeDown()
    end
end
function drop_all_bottom()
    local slot = 1
    local data

    while slot <= 16 do
        data = turtle.getItemDetail(slot)
        if data and data.name ~= "minecraft:coal" then
            turtle.select(slot)
            if not turtle.dropDown() then
                break
            end
        end
        slot = slot + 1
    end
end
function get_chest_presence()
    local success, data = turlte.inspectDown()

    if success and data.name == "minecraft:chest" then
        drop_all_bottom()
    end
end
function multavance(x)
    while x > 0 do
        avance()
        x = x - 1
    end
end
function goto_base_and_drop(x, y)
    turtle.turnLeft()
    turtle.turnLeft()
    multavance(x)
    turtle.turnRight()
    multavance(y)
    turtle.turnRight()
    drop_all_bottom()
    turtle.turnRight()
    multavance(y)
    turtle.turnLeft()
    multavance(x)
end
function select_next_item(slot, item)
    local data

    while slot <= 16 do
        data = turtle.getItemDetail(slot)
        if data and data.name == item then
            turtle.select(slot)
            return true
        end
        slot = slot + 1
    end
    return false
end
function repack_item(item)
    local slot = 1
    local data

    while slot < 16 do
        data = turtle.getItemDetail(slot)
        if not data or (data.name == item and data.count < 64) then
            if select_next_item(slot + 1, item) then
                turtle.transferTo(slot)
                data = turtle.getItemDetail(slot)
            else
                return true
            end
        end
        if data and ((data.name == item and data.count == 64) or data.name ~= item) then
            slot = slot + 1
        end
    end
    return true
end
function clean_inventory(x, y)
    local slot = 1
    local data

    while slot <= 16 do
        data = turtle.getItemDetail(slot)
        if data and (data.name == "minecraft:diamond" or data.name == "minecraft:emerald" or data.name == "minecraft:redstone" or data.name == "minecraft:iron_ore" or data.name == "minecraft:gold_ore" or data.name == "minecraft:coal" or (data.name == "minecraft:dye" and data.damage == 4) or data.name == "minecraft:lava_bucket" or data.name == "minecraft:coal" or data.name == "minecraft:planks" or data.name == "minecraft:log" or data.name == "minecraft:sand") then
            repack_item(data.name)
        elseif data then
            turtle.select(slot)
            turtle.drop()
        end
        slot = slot + 1
    end
    if is_inventory_full() then
        goto_base_and_drop(x, y)
    end
end

local x, y = 0, 0
print("How metters dig in front off ?")
local xmax = tonumber(read())
print("How metters dig at right ?")
local ymax = tonumber(read())
local grav = 0

while y < ymax or x < xmax do
    check_fuel()
    if turtle.detectUp() then dig_collumn(0) end
    grav = 0
    if x == xmax then
        while x > 0 do
            recule()
            x = x - 1
        end
        turtle.turnRight()
        avance()
        turtle.turnLeft()
        y = y + 1
    else
        grav = avance()
        x = x + 1
    if turtle.detectUp() or grav > 0 then dig_collumn(grav) end
    if stone_down() then replace_bloc_by_dirt() end
    if is_inventory_full() then clean_inventory(x, y) end
    end
end