PyuTest.make_upgrade_rune = function(name, desc, stat, increase, max, color, craftitem)
  PyuTest.make_item(name, desc, {
    upgrade_rune = 1,
  }, "pyutest-rune.png", {
    color = color,
    on_use = function(itemstack, user, pointed_thing)
      if not user then return end
      if not user:is_player() then return end

      local value = PyuTest.get_player_stat(user, stat)

      if value == max then
        return
      end

      -- Stat value below 1 causes problems
      if (value + increase) < 1 then
        return
      end

      PyuTest.set_player_stat(user, stat, value + increase)

      core.sound_play({ name = "spellbook_action", gain = 0.75 }, { pos = user:get_pos() })
      itemstack:take_item()
      return itemstack
    end
  })

  if craftitem ~= nil then
    core.register_craft({
      output = name,
      recipe = {
        { "",                           "pyutest_ores:emerald_shard", "" },
        { "pyutest_ores:emerald_shard", craftitem,                    "pyutest_ores:emerald_shard" },
        { "",                           "pyutest_ores:emerald_shard", "" },
      }
    })
  end
end

PyuTest.make_upgrade_rune("pyutest_upgrades:defense", "Defense Upgrade Rune", "defense", 0.5, 5, "green",
  "pyutest_ores:diamond_shard")
PyuTest.make_upgrade_rune("pyutest_upgrades:attack", "Attack Upgrade Rune", "attack", 0.5, 3, "red",
  "pyutest_ores:gold_ingot")