musttest_game/mods/coal_alloy_furnace/init.lua

if not minetest.global_exists("coal_alloy_furnace") then coal_alloy_furnace = {} end
coal_alloy_furnace.modpath = minetest.get_modpath("coal_alloy_furnace")
local FURNACE_SPEED = 3.0

-- Localize for performance.
local math_floor = math.floor


-- Get active formspec.
coal_alloy_furnace.get_active_formspec = function(fuel_percent, item_percent)
  local formspec = 
    "size[8,8.5]"..
    default.formspec.get_form_colors() ..
    default.formspec.get_form_image() ..
    default.formspec.get_slot_colors() ..
    
    "label[1.75,0;Fuel & Input]" ..
    "list[context;src;1.75,0.5;2,1;]"..
    "list[context;fuel;2.26,2.5;1,1;]"..

		utility.progress_image(2.26, 1.5, "default_furnace_fire_bg.png", "default_furnace_fire_fg.png", fuel_percent) ..
		utility.progress_image(3.75, 1.5, "gui_furnace_arrow_bg.png", "gui_furnace_arrow_fg.png", item_percent, "^[transformR270") ..

    "label[4.75,0.46;Destination]" ..
    "list[context;dst;4.75,0.96;2,2;]"..
    "list[current_player;main;0,4.25;8,1;]"..
    "list[current_player;main;0,5.5;8,3;8]"..
    "listring[context;dst]"..
    "listring[current_player;main]"..
    "listring[context;src]"..
    "listring[current_player;main]"..
    "listring[context;fuel]"..
    "listring[current_player;main]"..
    default.get_hotbar_bg(0, 4.25)
  return formspec
end



coal_alloy_furnace.get_inactive_formspec = function()
  return coal_alloy_furnace.get_active_formspec(0, 0)
end



coal_alloy_furnace.can_dig = function(pos, player)
  local meta = minetest.get_meta(pos);
  local inv = meta:get_inventory()
  return inv:is_empty("fuel") and inv:is_empty("dst") and inv:is_empty("src")
end



coal_alloy_furnace.allow_metadata_inventory_put = function(pos, listname, index, stack, player)
  if minetest.test_protection(pos, player:get_player_name()) then
    return 0
  end
  local meta = minetest.get_meta(pos)
  local inv = meta:get_inventory()
  if listname == "fuel" then
    if minetest.get_craft_result({method="coalfuel", width=1, items={stack}}).time ~= 0 then
      if inv:is_empty("src") then
        meta:set_string("infotext", "Fuel-Fired Alloy Furnace is Empty.")
      end
      return stack:get_count()
    else
      return 0
    end
  elseif listname == "src" then
    return stack:get_count()
  elseif listname == "dst" then
    return 0
  end
end



coal_alloy_furnace.allow_metadata_inventory_move = function(pos, from_list, from_index, to_list, to_index, count, player)
  local meta = minetest.get_meta(pos)
  local inv = meta:get_inventory()
  local stack = inv:get_stack(from_list, from_index)
  return coal_alloy_furnace.allow_metadata_inventory_put(pos, to_list, to_index, stack, player)
end



coal_alloy_furnace.allow_metadata_inventory_take = function(pos, listname, index, stack, player)
  if minetest.test_protection(pos, player:get_player_name()) then
    return 0
  end
  return stack:get_count()
end



coal_alloy_furnace.on_timer = function(pos, elapsed)
  --
  -- Inizialize metadata
  --
  local meta = minetest.get_meta(pos)
  local fuel_time = meta:get_float("fuel_time") or 0
  local src_time = meta:get_float("src_time") or 0
  local fuel_totaltime = meta:get_float("fuel_totaltime") or 0

  local inv = meta:get_inventory()
  local srclist = inv:get_list("src")
  local fuellist = inv:get_list("fuel")

  --
  -- Cooking
  --

  -- Check if we have cookable content
  local cooked, aftercooked = minetest.get_craft_result({method = "alloying", width = 1, items = srclist})
  local cookable = true

  if cooked.time == 0 then
    cookable = false
	else
		cooked.time = cooked.time * FURNACE_SPEED
  end

  -- Check if we have enough fuel to burn
  if fuel_time < fuel_totaltime then
    -- The furnace is currently active and has enough fuel
    fuel_time = fuel_time + 1

    -- If there is a cookable item then check if it is ready yet
    if cookable then
      src_time = src_time + 1
      if src_time >= cooked.time then
        -- Place result in dst list if possible
        if inv:room_for_item("dst", cooked.item) then
          inv:add_item("dst", cooked.item)
          inv:set_stack("src", 1, aftercooked.items[1])
          inv:set_stack("src", 2, aftercooked.items[2])
          src_time = 0
        end
      end
    end
  else
    -- Furnace ran out of fuel
    if cookable then
      -- We need to get new fuel
      local fuel, afterfuel = minetest.get_craft_result({method = "coalfuel", width = 1, items = fuellist})

      if fuel.time == 0 then
        -- No valid fuel in fuel list
        fuel_totaltime = 0
        fuel_time = 0
        src_time = 0
      else
        -- Take fuel from fuel list
        inv:set_stack("fuel", 1, afterfuel.items[1])

        fuel_totaltime = fuel.time * FURNACE_SPEED
        fuel_time = 0
      end
    else
      -- We don't need to get new fuel since there is no cookable item
      fuel_totaltime = 0
      fuel_time = 0
      src_time = 0
    end
  end

  --
  -- Update formspec, infotext and node
  --
  local formspec = coal_alloy_furnace.get_inactive_formspec()
  local item_state
  local item_percent = 0
  if cookable then
    item_percent = math_floor(src_time / cooked.time * 100)
    if item_percent > 100 then
      item_state = "100% (Output Full)"
    else
      item_state = item_percent .. "%"
    end
  else
    if srclist[1]:is_empty() then
      item_state = "Empty"
    else
      item_state = "Not Alloyable"
    end
  end

  local fuel_state = "Empty"
  local active = "Inactive "
  local result = false

  if fuel_time <= fuel_totaltime and fuel_totaltime ~= 0 then
    active = "Active "
    local fuel_percent = 100 - math_floor(fuel_time / fuel_totaltime * 100)
    fuel_state = fuel_percent .. "%"
    formspec = coal_alloy_furnace.get_active_formspec(fuel_percent, item_percent)
		if machines.swap_node(pos, "coal_alloy_furnace:active") then
      torchmelt.start_melting(pos)
			notify.notify_adjacent(pos)
			ambiance.spawn_sound_beacon("ambiance:furnace_active", pos)
    end
    -- make sure timer restarts automatically
    result = true
  else
    if not fuellist[1]:is_empty() then
      fuel_state = "0%"
    end
    machines.swap_node(pos, "coal_alloy_furnace:inactive")
    -- stop timer on the inactive furnace
    local timer = minetest.get_node_timer(pos)
    timer:stop()
  end

  local infotext = "Fuel-Fired Alloy Furnace " .. active .. "\n" ..
    "Item: " .. item_state .. "\n" .. "Fuel Burn: " .. fuel_state

  --
  -- Set meta values
  --
  meta:set_float("fuel_totaltime", fuel_totaltime)
  meta:set_float("fuel_time", fuel_time)
  meta:set_float("src_time", src_time)
  meta:set_string("formspec", formspec)
  meta:set_string("infotext", infotext)

  return result
end



coal_alloy_furnace.on_blast = function(pos)
  local drops = {}
  default.get_inventory_drops(pos, "src", drops)
  default.get_inventory_drops(pos, "fuel", drops)
  default.get_inventory_drops(pos, "dst", drops)
  drops[#drops+1] = "coal_alloy_furnace:inactive"
  minetest.remove_node(pos)
  return drops
end



coal_alloy_furnace.on_construct = function(pos)
  local meta = minetest.get_meta(pos)
  meta:set_string("formspec", coal_alloy_furnace.get_inactive_formspec())
  local inv = meta:get_inventory()
  inv:set_size('src', 2)
  inv:set_size('fuel', 1)
  inv:set_size('dst', 4)
end



coal_alloy_furnace.on_metadata_inventory_move = function(pos)
  local timer = minetest.get_node_timer(pos)
  timer:start(1.0)
end



coal_alloy_furnace.on_metadata_inventory_put = function(pos)
  -- Start timer function, it will sort out whether furnace can burn or not.
  local timer = minetest.get_node_timer(pos)
  timer:start(1.0)
end

coal_alloy_furnace.burn_feet = function(pos, player)
	if not heatdamage.is_immune(player:get_player_name()) then
    utility.damage_player(player, "heat", 1*500)
	end
end



minetest.register_node("coal_alloy_furnace:inactive", {
  description = "Fuel-Fired Alloy Furnace\n\nThis combines materials by alloying.\nBurns coal or kalite for fuel.",
  tiles = {
    "coal_alloy_furnace_top.png", "coal_alloy_furnace_bottom.png",
    "coal_alloy_furnace_side.png", "coal_alloy_furnace_side.png",
    "coal_alloy_furnace_side.png", "coal_alloy_furnace_front.png"
  },
  
  groups = utility.dig_groups("machine", {
    tubedevice = 1, tubedevice_receiver = 1,
    immovable = 1,
  }),
  
  paramtype2 = "facedir",
  on_rotate = function(...) return screwdriver.rotate_simple(...) end,
  is_ground_content = false,
  sounds = default.node_sound_stone_defaults(),

  can_dig = function(...)
    return coal_alloy_furnace.can_dig(...) end,
  on_timer = function(...)
    return coal_alloy_furnace.on_timer(...) end,
  on_construct = function(...)
    return coal_alloy_furnace.on_construct(...) end,

  on_metadata_inventory_move = function(...)
    return coal_alloy_furnace.on_metadata_inventory_move(...) end,
  on_metadata_inventory_put = function(...)
    return coal_alloy_furnace.on_metadata_inventory_put(...) end,
  on_blast = function(...)
    return coal_alloy_furnace.on_blast(...) end,

  allow_metadata_inventory_put = function(...)
    return coal_alloy_furnace.allow_metadata_inventory_put(...) end,
  allow_metadata_inventory_move = function(...)
    return coal_alloy_furnace.allow_metadata_inventory_move(...) end,
  allow_metadata_inventory_take = function(...)
    return coal_alloy_furnace.allow_metadata_inventory_take(...) end,
})



minetest.register_node("coal_alloy_furnace:active", {
  description = "Fuel-Fired Alloy Furnace",
  tiles = {
    "coal_alloy_furnace_top.png", "coal_alloy_furnace_bottom.png",
    "coal_alloy_furnace_side.png", "coal_alloy_furnace_side.png",
    "coal_alloy_furnace_side.png", "coal_alloy_furnace_front_active.png",
  },
  light_source = 8,
  drop = "coal_alloy_furnace:inactive",
  
  groups = utility.dig_groups("machine", {
    not_in_creative_inventory=1, 
    melt_around = 4,
    tubedevice = 1, tubedevice_receiver = 1,
    immovable = 1,
  }),
  
  paramtype2 = "facedir",
  on_rotate = function(...) return screwdriver.rotate_simple(...) end,
  is_ground_content = false,
  sounds = default.node_sound_stone_defaults(),
  
  on_timer = function(...)
    return coal_alloy_furnace.on_timer(...) end,
  can_dig = function(...)
    return coal_alloy_furnace.can_dig(...) end,
  on_blast = function(...)
    return coal_alloy_furnace.on_blast(...) end,

  allow_metadata_inventory_put = function(...)
    return coal_alloy_furnace.allow_metadata_inventory_put(...) end,
  allow_metadata_inventory_move = function(...)
    return coal_alloy_furnace.allow_metadata_inventory_move(...) end,
  allow_metadata_inventory_take = function(...)
    return coal_alloy_furnace.allow_metadata_inventory_take(...) end,

	on_player_walk_over = function(...)
		return coal_alloy_furnace.burn_feet(...) end,
})



minetest.register_craft({
  output = 'coal_alloy_furnace:inactive',
  recipe = {
    {'default:brick', 'default:brick', 'default:brick'},
    {'default:brick', 'group:torch_craftitem',   'default:brick'},
    {'default:brick', 'default:brick', 'default:brick'},
  }
})