-- Minetest Mod: hotbar
--      Version: 0.1.5a+mtsr01
--   Licence(s): see the attached license.txt file
--       Authors:
--           - aristotle, a builder on Red Cat Creative
--           - VinAdmin
--
-- This mod allows the player to set his/her own hotbar slots number
-- by adding a new command.
--
--   hotbar [size]
--
-- By itself, hotbar types the hotbar slots number in the chat;
-- when it is followed by a number in the correct range that is now [0,23],
-- the command accordingly sets the new slots number.
--
-- Features:
-- - It may permanently store the user's preferences by setting & retrieving
--   the "hotbar_slots" & "hotbar_mode" keys in the configuration file.
-- - For those of us who are running MT 0.4.16+, the hotbar size may be
--   different in each world / map.
--
-- Changelog:
--   0.1.5a
--   - Running luacheck underlined that a couple of fixes were needed:
--     1. normalize() scope is now local
--     2. a few lines had their trailing blanks removed.
--   - A couple of "security fixes" have been applied to disallow any
--     floating value inside minetest.conf and the modstorage that might
--     have made the mod fail at load time in legacy and world mode.
--   0.1.5
--   - Went back to just one command: hotbar, now improved to just not take
--     the size, but the mode as well.
--   - Some feedback messages have been fixed.
--   0.1.4
--   - A new command - /hotbar_mode - has been added to take advantage of
--     the 0.4.16+ mod_storage API.
--     In singleplayer, the suggested default mode for the most recent
--     clients (0.4.16+) should now be WORLD, because when this mode is
--     active a different size can be stored in each world.
--     The original global behavior / mode is now called LEGACY, and
--     should be the default and only one for any MT < 0.4.16
--     because of the lack of the mod_storage API (not tested).
--     No further effort will be put to provide an alternative storage
--     system for any MT < 0.4.16.
--     A third mode - SESSION - is the only mode available when the mod
--     is running on a server. The player can change the slots number,
--     but every new session its value is restored to the default.
--     The SESSION mode is available in singleplayer too.
--   - The slots range has been extended to include the 0: because of this
--     it is now possible to hide the hotbar, the wielded item (and,
--     consequently, the hand).
--   - The deprecated minetest.setting_{get,set}() calls have been removed:
--     this avoids some warnings, but might at the same time limit the
--     compatibility with MT versions < 0.4.16 (not tested too).
--   - The code has been refactoried to better support future comprehension
--     and extensibility (eg for a clientmod version): most of it should
--     now be hopefully self explainatory to me! and even to the occasional
--     modder. :D
--   - FIXES
--     - The slots number is now checked not to be a float (ty GreenDimond).
--   0.1.3
--   - New update to assure the full API support because the version 0.1.2
--     update seems to have gone wrong for some reason. (SORRY. Ty _Xenon)
--     The accepted slots number should now be in the range [1,23]!
--   0.1.2
--   - Some of the existing textures have been modified to comply with an even
--     size (as recommended)
--   - The missing textures have been added.
--   - Some of the textures have been renamed to better support sorting.
--   - As a consequence, the size range has been extended from [1,16] to the
--     fully supported one [1,23]
--   0.1.1
--   - The code that did not properly show the error message when the
--     received size was out of bounds has been corrected
--   - The accepted range has been extended from [4,16] to [1,16].
--   - Some code optimization to avoid strings repetitions
--   0.1.0
--   - The hotbar is now correctly shown even when there are no items in it.
--
-- For now this is all folks: happy builds and explorations! :)
-- aristotle

local VERSION = "0.1.5a+mtsr01"
local MODES = {legacy = "legacy", world = "world", session = "session"} -- this redundancy simplifies later checks
local DEFAULT = {mode = MODES.world, slots = {legacy = 16, world = 10, session = 12}}
local MOD_STORAGE = {}

local new_masked_array = function(mask, max)
  local rc = {}
  for i = 1, max do
    table.insert(rc, string.format(mask, i))
  end
  return rc
end

local read_mode = function(key, default_value)
  if not core.is_singleplayer() then
    return MODES.session
  end
  local value = core.settings:get(key)
  if type(value) ~= "string" or #value == 0 then
    return default_value
  end
  value = string.lower(value)
  if not MODES[value] then
    value = default_value
  end
  return value
end

local get_mode = function(storage, key, default_value)
  if not core.is_singleplayer() then
    return MODES.session
  end
  local value = read_mode(key, default_value)
  local wrong = false
  if value == MODES.world then
    if not storage.present then
      value = MODES.legacy
      wrong = true
    end
  end
  if wrong then
     core.settings:set(key, value)
  end
  return value
end

local get_and_set_initial_slots = function(storage, mode_value, key, default_value)
  local current
  if not core.is_singleplayer() then
    mode_value = MODES.session
    default_value = DEFAULT.slots[mode_value]
  end

  if mode_value == MODES.legacy then
    local result = tonumber(core.settings:get(key))
    current = result or default_value  -- The first time
    if not result then
      -- first time
      core.settings:set(key, current)
    else
      current = math.floor(result)
      if current ~= result then
        -- result is a float
        core.settings:set(key, current)
      end
    end

  elseif mode_value == MODES.world then
    local result = core.deserialize(storage.settings:get_string(key))
    if type(result) == "number" then
      current = math.floor(result)
      if current ~= result then
        -- result is a float
        storage.settings:set_string(key, core.serialize(current))
      end
    else
      current = default_value -- The first time
      storage.settings:set_string(key, core.serialize(current))
    end

  elseif mode_value == MODES.session then
      current = default_value -- Session initial value

  else
    current = default_value -- Unplanned case
  end

  return current
end

local adjust_hotbar = function(name, slots, selected_image, bg_image_getter)
  local player = core.get_player_by_name(name)
    player:hud_set_hotbar_itemcount(slots)
    player:hud_set_hotbar_selected_image(selected_image)
    player:hud_set_hotbar_image(bg_image_getter(slots))
    player:hud_set_flags({hotbar = true, wielditem = true})
end

local hb = {}

hb.adjust = adjust_hotbar

hb.mode = { key = "hotbar_mode" }
hb.slots = { key = "hotbar_slots", min = 0, max = 23 }
hb.image = { selected = "hotbar_selected_slot.png", bg = {} }

hb.mode.current = get_mode(MOD_STORAGE, hb.mode.key, DEFAULT.mode)
hb.slots.current = get_and_set_initial_slots(MOD_STORAGE, hb.mode.current, hb.slots.key, DEFAULT.slots[hb.mode.current])
hb.image.bg.array = new_masked_array("hotbar_slots_bg_%02i.png", hb.slots.max)

hb.image.bg.get = function(slots)
  return hb.image.bg.array[tonumber(slots)]
end

hb.slots.set = function(name, slots)
  slots = math.floor(slots) -- to avoid fractions
  hb.adjust(name, slots, hb.image.selected, hb.image.bg.get)
end

minetest.register_privilege("builder", {
	description = "Privilege for builders",
	give_to_singleplayer = false
})

minetest.register_on_joinplayer(function(player)
	if minetest.check_player_privs(player, {builder=true}) then
		--player:hud_set_hotbar_itemcount(tonumber(16))
    	--player:hud_set_hotbar_image("")
    	hb.adjust(player:get_player_name(), 16, hb.image.selected, hb.image.bg.get)
	end
end)