Update doc_items (fake items)

[MineClone/MineClone2.git] / mods / HELP / doc / doc_items / init.lua

-- Boilerplate to support localized strings if intllib mod is installed.
local S
if minetest.get_modpath("intllib") then
        S = intllib.Getter()
else
        S = function(s,a,...)a={a,...}return s:gsub("@(%d+)",function(n)return a[tonumber(n)]end)end
end

doc.sub.items = {}

-- Template texts
doc.sub.items.temp = {}
doc.sub.items.temp.deco = S("This is a decorational block.")
doc.sub.items.temp.build = S("This block is a building block for creating various buildings.")
doc.sub.items.temp.craftitem = S("This item is primarily used for crafting other items.")

doc.sub.items.temp.eat = S("Hold it in your hand, then leftclick to eat it.")
doc.sub.items.temp.eat_bad = S("Hold it in your hand, then leftclick to eat it. But why would you want to do this?")
doc.sub.items.temp.rotate_node = S("This block's rotation is affected by the way you place it: Place it on the floor or ceiling for a vertical orientation; place it at the side for a horizontal orientation. Sneaking while placing it leads to a perpendicular orientation instead.")

doc.sub.items.settings = {}
doc.sub.items.settings.friendly_group_names = false
local setting = minetest.settings:get_bool("doc_items_friendly_group_names")
if setting ~= nil then
        doc.sub.items.settings.friendly_group_names = setting
end
doc.sub.items.settings.itemstring = false
setting = minetest.settings:get_bool("doc_items_show_itemstrings")
if setting ~= nil then
        doc.sub.items.settings.itemstring = setting
end

-- Local stuff
local groupdefs = {}
local mininggroups = {}
local miscgroups = {}
local item_name_overrides = {
        [""] = S("Hand"),
        ["air"] = S("Air")
}
local suppressed = {
        ["ignore"] = true,
}

-- This table contains which of the builtin factoids must NOT be displayed because
-- they have been disabled by a mod
local forbidden_core_factoids = {}

-- Helper functions
local yesno = function(bool)
        if bool==true then return S("Yes")
        elseif bool==false then return S("No")
        else return "N/A" end
end

local groups_to_string = function(grouptable, filter)
        local gstring = ""
        local groups_count = 0
        for id, value in pairs(grouptable) do
                if (filter == nil or filter[id] == true) then
                        -- Readable group name
                        if groups_count > 0 then
                                -- List seperator
                                gstring = gstring .. S(", ")
                        end
                        if groupdefs[id] ~= nil and doc.sub.items.settings.friendly_group_names == true then
                                gstring = gstring .. groupdefs[id]
                        else
                                gstring = gstring .. id
                        end
                        groups_count = groups_count + 1
                end
        end
        if groups_count == 0 then
                return nil, 0
        else
                return gstring, groups_count
        end
end

-- Replaces all newlines with spaces
local scrub_newlines = function(text)
        local new, x = string.gsub(text, "\n", " ")
        return new
end

--[[ Append a newline to text, unless it already ends with a newline. ]]
local newline = function(text)
        if string.sub(text, #text, #text) == "\n" or text == "" then
                return text
        else
                return text .. "\n"
        end
end

--[[ Make sure the text ends with two newlines by appending any missing newlines at the end, if neccessary. ]]
local newline2 = function(text)
        if string.sub(text, #text-1, #text) == "\n\n" or text == "" then
                return text
        elseif string.sub(text, #text, #text) == "\n" then
                return text .. "\n"
        else
                return text .. "\n\n"
        end
end


-- Extract suitable item description for formspec
local description_for_formspec = function(itemstring)
        if minetest.registered_items[itemstring] == nil then
                -- Huh? The item doesn't exist for some reason. Better give a dummy string
                minetest.log("warning", "[doc] Unknown item detected: "..tostring(itemstring))
                return S("Unknown item (@1)", tostring(itemstring))
        end
        local description = minetest.registered_items[itemstring].description
        if description == nil or description == "" then
                return minetest.formspec_escape(itemstring)
        else
                return minetest.formspec_escape(scrub_newlines(description))
        end
end

local get_entry_name = function(itemstring)
        local def = minetest.registered_items[itemstring]
        if def._doc_items_entry_name ~= nil then
                return def._doc_items_entry_name
        elseif item_name_overrides[itemstring] ~= nil then
                return item_name_overrides[itemstring]
        else
                return def.description
        end
end

doc.sub.items.get_group_name = function(groupname)
        if groupdefs[groupname] ~= nil and doc.sub.items.settings.friendly_group_names == true then
                return groupdefs[groupname]
        else
                return groupname
        end
end

local burntime_to_text = function(burntime)
        if burntime == nil then
                return S("unknown")
        elseif burntime == 1 then
                return S("1 second")
        else
                return S("@1 seconds", burntime)
        end
end

--[[ Convert tool capabilities to readable text. Extracted information:
* Mining capabilities
* Durability (when mining
* Full punch interval
* Damage groups
]]
local factoid_toolcaps = function(tool_capabilities, check_uses)
        if forbidden_core_factoids.tool_capabilities then
                return ""
        end

        local formstring = ""
        if check_uses == nil then check_uses = false end
        if tool_capabilities ~= nil and tool_capabilities ~= {} then
                local groupcaps = tool_capabilities.groupcaps
                if groupcaps ~= nil then
                        local miningcapstr = ""
                        local miningtimesstr = ""
                        local miningusesstr = ""
                        local caplines = 0
                        local timelines = 0
                        local useslines = 0
                        for k,v in pairs(groupcaps) do
                                -- Mining capabilities
                                local minrating, maxrating
                                if v.times then
                                        for rating, time in pairs(v.times) do
                                                if minrating == nil then minrating = rating else
                                                        if minrating > rating then minrating = rating end
                                                end
                                                if maxrating == nil then maxrating = rating else
                                                        if maxrating < rating then maxrating = rating end
                                                end
                                        end
                                else
                                        minrating = 1
                                        maxrating = 1
                                end
                                local maxlevel = v.maxlevel
                                if not maxlevel then
                                        -- Default from tool.h
                                        maxlevel = 1
                                end
                                miningcapstr = miningcapstr .. S("• @1: @2", doc.sub.items.get_group_name(k), maxlevel)
                                miningcapstr = miningcapstr .. "\n"
                                caplines = caplines + 1

                                for rating=3, 1, -1 do
                                        if v.times ~= nil and v.times[rating] ~= nil then
                                                local maxtime = v.times[rating]
                                                local mintime
                                                local mintimestr, maxtimestr
                                                local maxlevel_calc = maxlevel
                                                if maxlevel_calc < 1 then
                                                        maxlevel_calc = 1
                                                end
                                                mintime = maxtime / maxlevel_calc
                                                mintimestr = string.format("%.1f", mintime)
                                                maxtimestr = string.format("%.1f", maxtime)
                                                if mintimestr ~= maxtimestr then
                                                        miningtimesstr = miningtimesstr ..
                                                                S("• @1, rating @2: @3 s - @4 s",
                                                                doc.sub.items.get_group_name(k), rating,
                                                                mintimestr, maxtimestr)
                                                else
                                                        miningtimesstr = miningtimesstr ..
                                                                S("• @1, rating @2: @3 s",
                                                                doc.sub.items.get_group_name(k), rating,
                                                                mintimestr)
                                                end
                                                miningtimesstr = miningtimesstr.. "\n"
                                                timelines = timelines + 1
                                        end
                                end

                                -- Number of mining uses
                                local base_uses = v.uses
                                if not base_uses then
                                        -- Default from tool.h
                                        base_uses = 20
                                end
                                if check_uses and base_uses > 0 then
                                        for level=0, maxlevel do
                                                local real_uses = base_uses * math.pow(3, maxlevel - level)
                                                if real_uses < 65535 then
                                                        miningusesstr = miningusesstr .. S("• @1, level @2: @3 uses", doc.sub.items.get_group_name(k), level, real_uses)
                                                else
                                                        miningusesstr = miningusesstr .. S("• @1, level @2: Unlimited", doc.sub.items.get_group_name(k), level)
                                                end
                                                miningusesstr = miningusesstr .. "\n"
                                                useslines = useslines + 1
                                        end
                                end
                        end
                        if caplines > 0 then
                                formstring = formstring .. S("This tool is capable of mining.") .. "\n"
                                formstring = formstring .. S("Maximum toughness levels:") .. "\n"
                                formstring = formstring .. miningcapstr
                                formstring = newline(formstring)
                        end
                        if timelines > 0 then
                                formstring = formstring .. S("Mining times:") .. "\n"
                                formstring = formstring .. miningtimesstr
                        end
                        if useslines > 0 then
                                formstring = formstring .. S("Mining durability:") .. "\n"
                                formstring = formstring .. miningusesstr
                        end
                        if caplines > 0 or useslines > 0 or timelines > 0 then
                                formstring = newline2(formstring)
                        end
                end

                -- Weapon data
                local damage_groups = tool_capabilities.damage_groups
                if damage_groups ~= nil then
                        formstring = formstring .. S("This is a melee weapon which deals damage by punching.") .. "\n"
                        -- Damage groups
                        formstring = formstring .. S("Maximum damage per hit:") .. "\n"
                        for k,v in pairs(damage_groups) do
                                formstring = formstring .. S("• @1: @2 HP", doc.sub.items.get_group_name(k), v)
                                formstring = formstring .. "\n"
                        end

                        -- Full punch interval
                        local punch = 1.0
                        if tool_capabilities.full_punch_interval ~= nil then
                                punch = tool_capabilities.full_punch_interval
                        end
                        formstring = formstring .. S("Full punch interval: @1 s", string.format("%.1f", punch))
                        formstring = formstring .. "\n"
                end

        end
        return formstring
end

--[[ Factoid for the mining times properties of a node. Extracted infos:
- dig_immediate group
- Digging times/groups
- level group
]]
local factoid_mining_node = function(data)
        if forbidden_core_factoids.node_mining then
                return ""
        end

        local datastring = ""
        if data.def.pointable ~= false and (data.def.liquid_type == "none" or data.def.liquid_type == nil) then
                -- Check if there are no mining groups at all
                local nogroups = true
                for groupname,_ in pairs(mininggroups) do
                        if data.def.groups[groupname] ~= nil or groupname == "dig_immediate" then
                                nogroups = false
                                break
                        end
                end
                -- dig_immediate
                if data.def.drop ~= "" then
                        if data.def.groups.dig_immediate == 2 then
                                datastring = datastring .. S("This block can be mined by any mining tool in half a second.").."\n"
                        elseif data.def.groups.dig_immediate == 3 then
                                datastring = datastring .. S("This block can be mined by any mining tool immediately.").."\n"
                        -- Note: “unbreakable” is an unofficial group for undiggable blocks
                        elseif data.def.diggable == false or nogroups or data.def.groups.immortal == 1 or data.def.groups.unbreakable == 1 then
                                datastring = datastring .. S("This block can not be mined by ordinary mining tools.").."\n"
                        end
                else
                        if data.def.groups.dig_immediate == 2 then
                                datastring = datastring .. S("This block can be destroyed by any mining tool in half a second.").."\n"
                        elseif data.def.groups.dig_immediate == 3 then
                                datastring = datastring .. S("This block can be destroyed by any mining tool immediately.").."\n"
                        elseif data.def.diggable == false or nogroups or data.def.groups.immortal == 1 or data.def.groups.unbreakable == 1 then
                                datastring = datastring .. S("This block can not be destroyed by ordinary mining tools.").."\n"
                        end
                end
                -- Expose “ordinary” mining groups (crumbly, cracky, etc.) and level group
                -- Skip this for immediate digging to avoid redundancy
                if data.def.groups.dig_immediate ~= 3 then
                        local mstring = S("This block can be mined by mining tools which match any of the following mining ratings and its toughness level.").."\n"
                        mstring = mstring .. S("Mining ratings:").."\n"
                        local minegroupcount = 0
                        for group,_ in pairs(mininggroups) do
                                local rating = data.def.groups[group]
                                if rating ~= nil then
                                        mstring = mstring .. S("• @1: @2", doc.sub.items.get_group_name(group), rating).."\n"
                                        minegroupcount = minegroupcount + 1
                                end
                        end
                        local level = data.def.groups.level
                        if not level then
                                level = 0
                        end
                        mstring = mstring .. S("Toughness level: @1", level).."\n"

                        if minegroupcount > 0 then
                                datastring = datastring .. mstring
                        end
                end
        end
        return datastring
end

-- Pointing range of itmes
local range_factoid = function(itemstring, def)
        local handrange = minetest.registered_items[""].range
        local itemrange = def.range
        if itemstring == "" then
                if handrange ~= nil then
                        return S("Range: @1", itemrange)
                else
                        return S("Range: 4")
                end
        else
                if handrange == nil then handrange = 4 end
                if itemrange ~= nil then
                        return S("Range: @1", itemrange)
                else
                        return S("Range: @1 (@2)", get_entry_name(""), handrange)
                end
        end
end

-- Smelting fuel factoid
local factoid_fuel = function(itemstring, ctype)
        if forbidden_core_factoids.fuel then
                return ""
        end

        local formstring = ""
        local result, decremented =  minetest.get_craft_result({method = "fuel", items = {itemstring}})
        if result ~= nil and result.time > 0 then
                local base
                local burntext = burntime_to_text(result.time)
                if ctype == "tools" then
                        base = S("This tool can serve as a smelting fuel with a burning time of @1.", burntext)
                elseif ctype == "nodes" then
                        base = S("This block can serve as a smelting fuel with a burning time of @1.", burntext)
                else
                        base = S("This item can serve as a smelting fuel with a burning time of @1.", burntext)
                end
                formstring = formstring .. base
                local replaced = decremented.items[1]:get_name()
                if not decremented.items[1]:is_empty() and replaced ~= itemstring then
                        formstring = formstring .. S(" Using it as fuel turns it into: @1.", description_for_formspec(replaced))
                end
                formstring = newline(formstring)
        end
        return formstring
end

-- Shows the itemstring of an item
local factoid_itemstring = function(itemstring, playername)
        if forbidden_core_factoids.itemstring then
                return ""
        end

        local privs = minetest.get_player_privs(playername)
        if doc.sub.items.settings.itemstring or (privs.give or privs.debug) then
                return S("Itemstring: \"@1\"", itemstring)
        else
                return ""
        end
end

local entry_image = function(data)
        local formstring = ""
        -- No image for air
        if data.itemstring ~= "air" then
                -- Hand
                if data.itemstring == "" then
                        formstring = formstring .. "image["..(doc.FORMSPEC.ENTRY_END_X-1)..","..doc.FORMSPEC.ENTRY_START_Y..";1,1;"..
                                minetest.registered_items[""].wield_image.."]"
                -- Other items
                elseif data.image ~= nil then
                        formstring = formstring .. "image["..(doc.FORMSPEC.ENTRY_END_X-1)..","..doc.FORMSPEC.ENTRY_START_Y..";1,1;"..data.image.."]"
                else
                        formstring = formstring .. "item_image["..(doc.FORMSPEC.ENTRY_END_X-1)..","..doc.FORMSPEC.ENTRY_START_Y..";1,1;"..data.itemstring.."]"
                end
        end
        return formstring
end

-- Stuff for factoids
local factoid_generators = {}
factoid_generators.nodes = {}
factoid_generators.tools = {}
factoid_generators.craftitems = {}

--[[ Returns a list of all registered factoids for the specified category and type
* category_id: Identifier of the Documentation System category in which the factoid appears
* factoid_type: If set, oly returns factoid with a matching factoid_type.
                If nil, all factoids for this category will be generated
* data: Entry data to parse ]]
local factoid_custom = function(category_id, factoid_type, data)
        local ftable = factoid_generators[category_id]
        local datastring = ""
        -- Custom factoids are inserted here
        for i=1,#ftable do
                if factoid_type == nil or ftable[i].ftype == factoid_type then
                        datastring = datastring .. ftable[i].fgen(data.itemstring, data.def)
                        if datastring ~= "" then
                                datastring = newline(datastring)
                        end
                end
        end
        return datastring
end

-- Shows core information shared by all items, to be inserted at the top
local factoids_header = function(data, ctype)
        local datastring = ""
        if not forbidden_core_factoids.basics then

                local longdesc = data.longdesc
                local usagehelp = data.usagehelp
                if longdesc ~= nil then
                        datastring = datastring .. S("Description: @1", longdesc)
                        datastring = newline2(datastring)
                end
                if usagehelp ~= nil then
                        datastring = datastring .. S("Usage help: @1", usagehelp)
                        datastring = newline2(datastring)
                end
                datastring = datastring .. factoid_custom(ctype, "use", data)
                datastring = newline2(datastring)

                if data.itemstring ~= "" then
                        datastring = datastring .. S("Maximum stack size: @1", data.def.stack_max)
                        datastring = newline(datastring)
                end
                datastring = datastring .. range_factoid(data.itemstring, data.def)

                datastring = newline2(datastring)

                if data.def.liquids_pointable == true then
                        if ctype == "nodes" then
                                datastring = datastring .. S("This block points to liquids.").."\n"
                        elseif ctype == "tools" then
                                datastring = datastring .. S("This tool points to liquids.").."\n"
                        elseif ctype == "craftitems" then
                                datastring = datastring .. S("This item points to liquids.").."\n"
                        end
                end
                        if data.def.on_use ~= nil then
                        if ctype == "nodes" then
                                datastring = datastring .. S("Punches with this block don't work as usual; melee combat and mining are either not possible or work differently.").."\n"
                        elseif ctype == "tools" then
                                datastring = datastring .. S("Punches with this tool don't work as usual; melee combat and mining are either not possible or work differently.").."\n"
                        elseif ctype == "craftitems" then
                                datastring = datastring .. S("Punches with this item don't work as usual; melee combat and mining are either not possible or work differently.").."\n"
                        end
                end

        end

        datastring = newline(datastring)

        -- Show tool capability stuff, including durability if not overwritten by custom field
        local check_uses = false
        if ctype == "tools" then
                check_uses = data.def._doc_items_durability == nil
        end
        datastring = datastring .. factoid_toolcaps(data.def.tool_capabilities, check_uses)
        datastring = newline2(datastring)

        return datastring
end

-- Shows less important information shared by all items, to be inserted at the bottom
local factoids_footer = function(data, playername, ctype)
        local datastring = ""
        datastring = datastring .. factoid_custom(ctype, "groups", data)
        datastring = newline2(datastring)

        -- Show other “exposable” groups
        if not forbidden_core_factoids.groups then
                local gstring, gcount = groups_to_string(data.def.groups, miscgroups)
                if gstring ~= nil then
                        if gcount == 1 then
                                if ctype == "nodes" then
                                        datastring = datastring .. S("This block belongs to the @1 group.", gstring) .. "\n"
                                elseif ctype == "tools" then
                                        datastring = datastring .. S("This tool belongs to the @1 group.", gstring) .. "\n"
                                elseif ctype == "craftitems" then
                                        datastring = datastring .. S("This item belongs to the @1 group.", gstring) .. "\n"
                                end
                        else
                                if ctype == "nodes" then
                                        datastring = datastring .. S("This block belongs to these groups: @1.", gstring) .. "\n"
                                elseif ctype == "tools" then
                                        datastring = datastring .. S("This tool belongs to these groups: @1.", gstring) .. "\n"
                                elseif ctype == "craftitems" then
                                        datastring = datastring .. S("This item belongs to these groups: @1.", gstring) .. "\n"
                                end
                        end
                end
        end
        datastring = newline2(datastring)

        -- Show fuel recipe
        datastring = datastring .. factoid_fuel(data.itemstring, ctype)
        datastring = newline2(datastring)

        -- Other custom factoids
        datastring = datastring .. factoid_custom(ctype, "misc", data)
        datastring = newline2(datastring)

        -- Itemstring
        datastring = datastring .. factoid_itemstring(data.itemstring, playername)

        return datastring
end

function doc.sub.items.register_factoid(category_id, factoid_type, factoid_generator)
        local ftable = { fgen = factoid_generator, ftype = factoid_type }
        if category_id == "nodes" or category_id == "tools" or category_id == "craftitems" then
                table.insert(factoid_generators[category_id], ftable)
                return true
        elseif category_id == nil then
                table.insert(factoid_generators.nodes, ftable)
                table.insert(factoid_generators.tools, ftable)
                table.insert(factoid_generators.craftitems, ftable)
                return false
        end
end

function doc.sub.items.disable_core_factoid(factoid_name)
        forbidden_core_factoids[factoid_name] = true
end

doc.add_category("nodes", {
        hide_entries_by_default = true,
        name = S("Blocks"),
        description = S("Item reference of blocks and other things which are capable of occupying space"),
        build_formspec = function(data, playername)
                if data then
                        local formstring = ""
                        local datastring = ""

                        formstring = entry_image(data)
                        datastring = factoids_header(data, "nodes")

                        local liquid = data.def.liquidtype ~= "none" and minetest.get_item_group(data.itemstring, "fake_liquid") == 0
                        if not forbidden_core_factoids.basics then
                                datastring = datastring .. S("Collidable: @1", yesno(data.def.walkable)) .. "\n"
                                if data.def.pointable == true then
                                        datastring = datastring .. S("Pointable: Yes") .. "\n"
                                elseif liquid then
                                        datastring = datastring .. S("Pointable: Only by special items") .. "\n"
                                else
                                        datastring = datastring .. S("Pointable: No") .. "\n"
                                end
                        end
                        datastring = newline2(datastring)
                        if not forbidden_core_factoids.liquid and liquid then
                                datastring = newline(datastring, false)
                                datastring = datastring .. S("This block is a liquid with these properties:") .. "\n"
                                local range, renew, viscos
                                if data.def.liquid_range then range = data.def.liquid_range else range = 8 end
                                if data.def.liquid_renewable ~= nil then renew = data.def.liquid_renewable else renew = true end
                                if data.def.liquid_viscosity then viscos = data.def.liquid_viscosity else viscos = 0 end
                                if renew then
                                        datastring = datastring .. S("• Renewable") .. "\n"
                                else
                                        datastring = datastring .. S("• Not renewable") .. "\n"
                                end
                                if range == 0 then
                                        datastring = datastring .. S("• No flowing") .. "\n"
                                else
                                        datastring = datastring .. S("• Flowing range: @1", range) .. "\n"
                                end
                                datastring = datastring .. S("• Viscosity: @1", viscos) .. "\n"
                        end
                        datastring = newline2(datastring)

                        -- Global factoids
                        --- Direct interaction with the player
                        ---- Damage (very important)
                        if not forbidden_core_factoids.node_damage then
                                if data.def.damage_per_second ~= nil and data.def.damage_per_second > 1 then
                                        datastring = datastring .. S("This block causes a damage of @1 hit points per second.", data.def.damage_per_second) .. "\n"
                                elseif data.def.damage_per_second == 1 then
                                        datastring = datastring .. S("This block causes a damage of @1 hit point per second.", data.def.damage_per_second) .. "\n"
                                end
                                if data.def.drowning then
                                        if data.def.drowning > 1 then
                                                datastring = datastring .. S("This block decreases your breath and causes a drowning damage of @1 hit points every 2 seconds.", data.def.drowning) .. "\n"
                                        elseif data.def.drowning == 1 then
                                                datastring = datastring .. S("This block decreases your breath and causes a drowning damage of @1 hit point every 2 seconds.", data.def.drowning) .. "\n"
                                        end
                                end
                                local fdap = data.def.groups.fall_damage_add_percent
                                if fdap ~= nil then
                                        if fdap > 0 then
                                                datastring = datastring .. S("The fall damage on this block is increased by @1%.", fdap) .. "\n"
                                        elseif fdap <= -100 then
                                                datastring = datastring .. S("This block negates all fall damage.") .. "\n"
                                        else
                                                datastring = datastring .. S("The fall damage on this block is reduced by @1%.", math.abs(fdap)) .. "\n"
                                        end
                                end
                        end
                        datastring = datastring .. factoid_custom("nodes", "damage", data)
                        datastring = newline2(datastring)

                        ---- Movement
                        if not forbidden_core_factoids.node_movement then
                                if data.def.groups.disable_jump == 1 then
                                        datastring = datastring .. S("You can not jump while standing on this block.").."\n"
                                end
                                if data.def.climbable == true then
                                        datastring = datastring .. S("This block can be climbed.").."\n"
                                end
                                local bouncy = data.def.groups.bouncy
                                if bouncy ~= nil then
                                        datastring = datastring .. S("This block will make you bounce off with an elasticity of @1%.", bouncy).."\n"
                                end
                                datastring = datastring .. factoid_custom("nodes", "movement", data)
                                datastring = newline2(datastring)
                        end

                        ---- Sounds
                        if not forbidden_core_factoids.sounds then
                                local function is_silent(def, soundtype)
                                        return type(def.sounds) ~= "table" or def.sounds[soundtype] == nil or def.sounds[soundtype] == "" or (type(data.def.sounds[soundtype]) == "table" and (data.def.sounds[soundtype].name == nil or data.def.sounds[soundtype].name == ""))
                                end
                                local silentstep, silentdig, silentplace = false, false, false
                                if data.def.walkable and is_silent(data.def, "footstep") then
                                        silentstep = true
                                end
                                if data.def.diggable and is_silent(data.def, "dig") and is_silent(data.def, "dug")  then
                                        silentdig = true
                                end
                                if is_silent(data.def, "place") and is_silent(data.def, "place_failed") and data.itemstring ~= "air" then
                                        silentplace = true
                                end
                                if silentstep and silentdig and silentplace then
                                        datastring = datastring .. S("This block is completely silent when walked on, mined or built.").."\n"
                                elseif silentdig and silentplace then
                                        datastring = datastring .. S("This block is completely silent when mined or built.").."\n"
                                else
                                        if silentstep then
                                                datastring = datastring .. S("Walking on this block is completely silent.").."\n"
                                        end
                                        if silentdig then
                                                datastring = datastring .. S("Mining this block is completely silent.").."\n"
                                        end
                                        if silentplace then
                                                datastring = datastring .. S("Building this block is completely silent.").."\n"
                                        end
                                end
                        end
                        datastring = datastring .. factoid_custom("nodes", "sound", data)
                        datastring = newline2(datastring)

                        -- Block activity
                        --- Gravity
                        if not forbidden_core_factoids.gravity then
                                if data.def.groups.falling_node == 1 then
                                        datastring = datastring .. S("This block is affected by gravity and can fall.").."\n"
                                end
                        end
                        datastring = datastring .. factoid_custom("nodes", "gravity", data)
                        datastring = newline2(datastring)

                        --- Dropping and destruction
                        if not forbidden_core_factoids.drop_destroy then
                                if data.def.buildable_to == true then
                                        datastring = datastring .. S("Building another block at this block will place it inside and replace it.").."\n"
                                        if data.def.walkable then
                                                datastring = datastring .. S("Falling blocks can go through this block; they destroy it when doing so.").."\n"
                                        end
                                end
                                if data.def.walkable == false then
                                        if data.def.buildable_to == false and data.def.drop ~= "" then
                                                datastring = datastring .. S("This block will drop as an item when a falling block ends up inside it.").."\n"
                                        else
                                                datastring = datastring .. S("This block is destroyed when a falling block ends up inside it.").."\n"
                                        end
                                end
                                if data.def.groups.attached_node == 1 then
                                        if data.def.paramtype2 == "wallmounted" then
                                                datastring = datastring .. S("This block will drop as an item when it is not attached to a surrounding block.").."\n"
                                        else
                                                datastring = datastring .. S("This block will drop as an item when no collidable block is below it.").."\n"
                                        end
                                end
                                if data.def.floodable == true then
                                        datastring = datastring .. S("Liquids can flow into this block and destroy it.").."\n"
                                end
                        end
                        datastring = datastring .. factoid_custom("nodes", "drop_destroy", data)
                        datastring = newline2(datastring)

                        -- Block appearance
                        --- Light
                        if not forbidden_core_factoids.light and data.def.light_source then
                                if data.def.light_source > 3 then
                                        datastring = datastring .. S("This block is a light source with a light level of @1.", data.def.light_source).."\n"
                                elseif data.def.light_source > 0 then
                                        datastring = datastring .. S("This block glows faintly with a light level of @1.", data.def.light_source).."\n"
                                end
                                if data.def.paramtype == "light" and data.def.sunlight_propagates then
                                        datastring = datastring .. S("This block allows light to propagate with a small loss of brightness, and sunlight can even go through losslessly.").."\n"
                                elseif data.def.paramtype == "light" then
                                        datastring = datastring .. S("This block allows light to propagate with a small loss of brightness.").."\n"
                                elseif data.def.sunlight_propagates then
                                        datastring = datastring .. S("This block allows sunlight to propagate without loss in brightness.").."\n"
                                end
                        end
                        datastring = datastring .. factoid_custom("nodes", "light", data)
                        datastring = newline2(datastring)

                        --- List nodes/groups to which this node connects to
                        if not forbidden_core_factoids.connects_to and data.def.connects_to ~= nil then
                                local nodes = {}
                                local groups = {}
                                for c=1,#data.def.connects_to do
                                        local itemstring = data.def.connects_to[c]
                                        if string.sub(itemstring,1,6) == "group:" then
                                                groups[string.sub(itemstring,7,#itemstring)] = 1
                                        else
                                                table.insert(nodes, itemstring)
                                        end
                                end

                                local nstring = ""
                                for n=1,#nodes do
                                        local name
                                        if item_name_overrides[nodes[n]] ~= nil then
                                                name = item_name_overrides[nodes[n]]
                                        else
                                                name = description_for_formspec(nodes[n])
                                        end
                                        if n > 1 then
                                                nstring = nstring .. S(", ")
                                        end
                                        if name ~= nil then
                                                nstring = nstring .. name
                                        else
                                                nstring = nstring .. S("Unknown Node")
                                        end
                                end
                                if #nodes == 1 then
                                        datastring = datastring .. S("This block connects to this block: @1.", nstring) .. "\n"
                                elseif #nodes > 1 then
                                        datastring = datastring .. S("This block connects to these blocks: @1.", nstring) .. "\n"
                                end

                                local gstring, gcount = groups_to_string(groups)
                                if gcount == 1 then
                                        datastring = datastring .. S("This block connects to blocks of the @1 group.", gstring) .. "\n"
                                elseif gcount > 1 then
                                        datastring = datastring .. S("This block connects to blocks of the following groups: @1.", gstring) .. "\n"
                                end
                        end

                        datastring = newline2(datastring)

                        -- Mining groups
                        datastring = datastring .. factoid_custom("nodes", "mining", data)

                        datastring = newline(datastring)

                        datastring = datastring .. factoid_mining_node(data)
                        datastring = newline2(datastring)

                        -- Non-default drops
                        if not forbidden_core_factoids.drops and data.def.drop ~= nil and data.def.drop ~= data.itemstring and data.itemstring ~= "air" then
                                -- TODO: Calculate drop probabilities of max > 1 like for max == 1
                                local get_desc = function(stack)
                                        return description_for_formspec(stack:get_name())
                                end
                                if data.def.drop == "" then
                                        datastring = datastring .. S("This block won't drop anything when mined.").."\n"
                                elseif type(data.def.drop) == "string" then
                                        local dropstack = ItemStack(data.def.drop)
                                        if dropstack:get_name() ~= data.itemstring and dropstack:get_name() ~= 1 then
                                                local desc = get_desc(dropstack)
                                                local count = dropstack:get_count()
                                                if count > 1 then
                                                        datastring = datastring .. S("This block will drop the following when mined: @1×@2.", count, desc).."\n"
                                                else
                                                        datastring = datastring .. S("This block will drop the following when mined: @1.", desc).."\n"
                                                end
                                        end
                                elseif type(data.def.drop) == "table" and data.def.drop.items ~= nil then
                                        local max = data.def.drop.max_items
                                        local dropstring = ""
                                        local dropstring_base = ""
                                        if max == nil then
                                                dropstring_base = S("This block will drop the following items when mined: %s.")
                                        elseif max == 1 then
                                                if #data.def.drop.items == 1 then
                                                        dropstring_base = S("This block will drop the following when mined: %s.")
                                                else
                                                        dropstring_base = S("This block will randomly drop one of the following when mined: %s.")
                                                end
                                        else
                                                dropstring_base = S("This block will randomly drop up to %d drops of the following possible drops when mined: %s.")
                                        end
                                        -- Save calculated probabilities into a table for later output
                                        local probtables = {}
                                        local probtable
                                        local rarity_history = {}
                                        for i=1,#data.def.drop.items do
                                                local local_rarity = data.def.drop.items[i].rarity
                                                local chance = 1
                                                local rarity = 1
                                                if local_rarity == nil then
                                                        local_rarity = 1
                                                end
                                                if max == 1 then
                                                        -- Chained probability
                                                        table.insert(rarity_history, local_rarity)
                                                        chance = 1
                                                        for r=1, #rarity_history do
                                                                local chance_factor
                                                                if r > 1 and rarity_history[r-1] == 1 then
                                                                        chance = 0
                                                                        break
                                                                end
                                                                if r == #rarity_history then
                                                                        chance_factor = 1/rarity_history[r]
                                                                else
                                                                        chance_factor = (rarity_history[r]-1)/rarity_history[r]
                                                                end
                                                                chance = chance * chance_factor
                                                        end
                                                        if chance > 0 then
                                                                rarity = 1/chance
                                                        end
                                                else
                                                        rarity = local_rarity
                                                        chance = 1/rarity
                                                end
                                                -- Exclude impossible drops
                                                if chance > 0 then
                                                        probtable = {}
                                                        probtable.items = {}
                                                        for j=1,#data.def.drop.items[i].items do
                                                                local dropstack = ItemStack(data.def.drop.items[i].items[j])
                                                                local itemstring = dropstack:get_name()
                                                                local desc = get_desc(dropstack)
                                                                local count = dropstack:get_count()
                                                                if not(itemstring == nil or itemstring == "" or count == 0) then
                                                                        if probtable.items[itemstring] == nil then
                                                                                probtable.items[itemstring] = {desc = desc, count = count}
                                                                        else
                                                                                probtable.items[itemstring].count = probtable.items[itemstring].count + count
                                                                        end
                                                                end
                                                        end
                                                        probtable.rarity = rarity
                                                        if #data.def.drop.items[i].items > 0 then
                                                                table.insert(probtables, probtable)
                                                        end
                                                end
                                        end
                                        -- Do some cleanup of the probability table
                                        if max == 1 or max == nil then
                                                -- Sort by rarity
                                                local comp = function(p1, p2) 
                                                        return p1.rarity < p2.rarity
                                                end
                                                table.sort(probtables, comp)
                                        end
                                        -- Output probability table
                                        local pcount = 0
                                        for i=1, #probtables do
                                                if pcount > 0 then
                                                        -- List seperator
                                                        dropstring = dropstring .. S(", ")
                                                end
                                                local probtable = probtables[i]
                                                local icount = 0
                                                local dropstring_this = ""
                                                for _, itemtable in pairs(probtable.items) do
                                                        if icount > 0 then
                                                                -- Final list seperator
                                                                dropstring_this = dropstring_this .. S(" and ")
                                                        end
                                                        local desc = S(itemtable.desc)
                                                        local count = itemtable.count
                                                        if count ~= 1 then
                                                                desc = S("@1×@2", count, desc)
                                                        end
                                                        dropstring_this = dropstring_this .. desc
                                                        icount = icount + 1
                                                end

                                                local rarity = probtable.rarity
                                                local raritystring = ""
                                                -- No percentage if there's only one possible guaranteed drop
                                                if not(rarity == 1 and #data.def.drop.items == 1) then
                                                        local chance = (1/rarity)*100
                                                        if rarity > 200 then -- <0.5%
                                                        -- For very low percentages
                                                                dropstring_this = S("@1 (<0.5%)", dropstring_this)
                                                        else
                                                                -- Add circa indicator for percentages with decimal point
                                                                local fchance = string.format("%.0f", chance)
                                                                if math.fmod(chance, 1) > 0 then
                                                                        dropstring_this = S("@1 (ca. @2%)", dropstring_this, fchance)
                                                                else
                                                                        dropstring_this = S("@1 (@2%)", dropstring_this, fchance)
                                                                end
                                                        end
                                                end
                                                dropstring = dropstring .. dropstring_this
                                                pcount = pcount + 1
                                        end
                                        if max ~= nil and max > 1 then
                                                datastring = datastring .. string.format(dropstring_base, max, dropstring)
                                        else
                                                datastring = datastring .. string.format(dropstring_base, dropstring)
                                        end
                                        datastring = newline(datastring)
                                end
                        end
                        datastring = datastring .. factoid_custom("nodes", "drops", data)
                        datastring = newline2(datastring)

                        datastring = datastring .. factoids_footer(data, playername, "nodes")

                        formstring = formstring .. doc.widgets.text(datastring, nil, nil, doc.FORMSPEC.ENTRY_WIDTH - 1.2)

                        return formstring
                else
                        return "label[0,1;NO DATA AVALIABLE!]"
                end
        end
})

doc.add_category("tools", {
        hide_entries_by_default = true,
        name = S("Tools and weapons"),
        description = S("Item reference of all wieldable tools and weapons"),
        sorting = "function",
        -- Roughly sort tools based on their capabilities. Tools which dig the same stuff end up in the same group
        sorting_data = function(entry1, entry2)
                local entries = { entry1, entry2 }
                -- Hand beats all
                if entries[1].eid == "" then return true end
                if entries[2].eid == "" then return false end

                local comp = {}
                for e=1, 2 do
                        comp[e] = {}
                end
                -- No tool capabilities: Instant loser
                if entries[1].data.def.tool_capabilities == nil and entries[2].data.def.tool_capabilities ~= nil then return false end
                if entries[2].data.def.tool_capabilities == nil and entries[1].data.def.tool_capabilities ~= nil then return true end
                -- No tool capabilities for both: Compare by uses
                if entries[1].data.def.tool_capabilities == nil and entries[2].data.def.tool_capabilities == nil then
                        for e=1, 2 do
                                if type(entries[e].data.def._doc_items_durability) == "number" then
                                        comp[e].uses = entries[e].data.def._doc_items_durability
                                else
                                        comp[e].uses = 0
                                end
                        end
                        return comp[1].uses > comp[2].uses
                end
                for e=1, 2 do
                        comp[e].gc = entries[e].data.def.tool_capabilities.groupcaps
                end
                -- No group capabilities = instant loser
                if comp[1].gc == nil then return false end
                if comp[2].gc == nil then return true end
                for e=1, 2 do
                        local groups = {}
                        local gc = comp[e].gc
                        local group = nil
                        local mintime =  nil
                        local groupcount = 0
                        local realuses = nil
                        for k,v in pairs(gc) do
                                local maxlevel = v.maxlevel
                                if maxlevel == nil then
                                        -- Default from tool.h
                                        maxlevel = 1
                                end
                                if groupcount == 0 then
                                        group = k
                                        local uses = v.uses
                                        if v.uses == nil then
                                                -- Default from tool.h
                                                uses = 20
                                        end
                                        realuses = uses * math.pow(3, maxlevel)
                                end
                                if v.times and #v.times > 1 then
                                        for rating, time in pairs(v.times) do
                                                local realtime = time / maxlevel
                                                if mintime == nil or realtime < mintime then
                                                        mintime = realtime
                                                end
                                        end
                                else
                                        mintime = 0
                                end
                                if groups[k] ~= true then
                                        groupcount = groupcount + 1
                                        groups[k] = true
                                end
                        end
                        comp[e].count = groupcount
                        comp[e].group = group
                        comp[e].mintime = mintime
                        if realuses ~= nil then
                                comp[e].uses = realuses
                        elseif type(entries[e].data.def._doc_items_durability) == "number" then
                                comp[e].uses = entries[e].data.def._doc_items_durability
                        else
                                comp[e].uses = 0
                        end
                end

                -- We want to sort out digging tools with multiple capabilities
                if comp[1].count > 1 and comp[1].count > comp[2].count then
                        return false
                elseif comp[1].group == comp[2].group then
                        -- Tiebreaker 1: Minimum digging time
                        if comp[1].mintime == comp[2].mintime then
                        -- Tiebreaker 2: Use count
                                return comp[1].uses > comp[2].uses
                        else
                                return comp[1].mintime < comp[2].mintime
                        end
                -- Final tiebreaker: Sort by group name
                else
                        if comp[1].group and comp[2].group then
                                return comp[1].group < comp[2].group
                        else
                                return false
                        end
                end
        end,
        build_formspec = function(data, playername)
                if data then
                        local formstring = ""
                        local datastring = ""

                        formstring = entry_image(data)
                        datastring = factoids_header(data, "tools")

                        -- Overwritten durability info
                        if type(data.def._doc_items_durability) == "number" then
                                -- Fixed number of uses
                                datastring = datastring .. S("Durability: @1 uses", data.def._doc_items_durability)
                                datastring = newline2(datastring)
                        elseif type(data.def._doc_items_durability) == "string" then
                                -- Manually described durability
                                datastring = datastring .. S("Durability: @1", data.def._doc_items_durability)
                                datastring = newline2(datastring)
                        end

                        datastring = datastring .. factoids_footer(data, playername, "tools")

                        formstring = formstring .. doc.widgets.text(datastring, nil, nil, doc.FORMSPEC.ENTRY_WIDTH - 1.2)

                        return formstring
                else
                        return "label[0,1;NO DATA AVALIABLE!]"
                end
        end
})

doc.add_category("craftitems", {
        hide_entries_by_default = true,
        name = S("Miscellaneous items"),
        description = S("Item reference of items which are neither blocks, tools or weapons (esp. crafting items)"),
        build_formspec = function(data, playername)
                if data then
                        local formstring = ""
                        local datastring = ""

                        formstring = entry_image(data)
                        datastring = factoids_header(data, "craftitems")
                        datastring = datastring .. factoids_footer(data, playername, "craftitems")

                        formstring = formstring .. doc.widgets.text(datastring, nil, nil, doc.FORMSPEC.ENTRY_WIDTH - 1.2)

                        return formstring
                else
                        return "label[0,1;NO DATA AVALIABLE!]"
                end
        end
})

-- Register group definition stuff
-- More (user-)friendly group names to replace the rather technical names
-- for better understanding
function doc.sub.items.add_friendly_group_names(groupnames)
        for internal, real in pairs(groupnames) do
                groupdefs[internal] = real
        end
end

-- Adds groups to be displayed in the generic “misc.” groups
-- factoid. Those groups should be neither be used as mining
-- groups nor as damage groups and should be relevant to the
-- player in someway.
function doc.sub.items.add_notable_groups(groupnames)
        for g=1,#groupnames do
                miscgroups[groupnames[g]] = true
        end
end

-- Collect information about all items
local function gather_descs()
        -- Internal help texts for default items
        local help = {
                longdesc = {},
                usagehelp = {},
        }

        -- 1st pass: Gather groups of interest
        for id, def in pairs(minetest.registered_items) do
                -- Gather all groups used for mining
                if def.tool_capabilities ~= nil then
                        local groupcaps = def.tool_capabilities.groupcaps
                        if groupcaps ~= nil then
                                for k,v in pairs(groupcaps) do
                                        if mininggroups[k] ~= true then
                                                mininggroups[k] = true
                                        end
                                end
                        end
                end

                -- ... and gather all groups which appear in crafting recipes
                local crafts = minetest.get_all_craft_recipes(id)
                if crafts ~= nil then
                        for c=1,#crafts do
                                for k,v in pairs(crafts[c].items) do
                                        if string.sub(v,1,6) == "group:" then
                                                local groupstring = string.sub(v,7,-1)
                                                local groups = string.split(groupstring, ",")
                                                for g=1, #groups do
                                                        miscgroups[groups[g]] = true
                                                end
                                        end
                                end
                        end
                end

                -- ... and gather all groups used in connects_to
                if def.connects_to ~= nil then
                        for c=1, #def.connects_to do
                                if string.sub(def.connects_to[c],1,6) == "group:" then
                                        local group = string.sub(def.connects_to[c],7,-1)
                                        miscgroups[group] = true
                                end
                        end
                end
        end

        -- 2nd pass: Add entries

        -- Set default air text
        -- Custom longdesc and usagehelp may be set by mods through the add_helptexts function
        if minetest.registered_items["air"]._doc_items_longdesc then
                help.longdesc["air"] = minetest.registered_items["air"]._doc.items_longdesc
        else
                help.longdesc["air"] = S("A transparent block, basically empty space. It is usually left behind after digging something.")
        end
        if minetest.registered_items["ignore"]._doc_items_create_entry ~= nil then
                suppressed["ignore"] = minetest.registered_items["ignore"]._doc_items_create_entry == true
        end

        -- Add entry for the default tool (“hand”)
        -- Custom longdesc and usagehelp may be set by mods through the add_helptexts function
        local handdef = minetest.registered_items[""]
        if handdef._doc_items_create_entry ~= false then
                if handdef._doc_items_longdesc then
                        help.longdesc[""] = handdef._doc_items_longdesc
                else
                        -- Default text
                        help.longdesc[""] = S("Whenever you are not wielding any item, you use the hand which acts as a tool with its own capabilities. When you are wielding an item which is not a mining tool or a weapon it will behave as if it would be the hand.")
                end
                if handdef._doc_items_entry_name then
                        item_name_overrides[""] = handdef._doc_items_entry_name
                end
                doc.add_entry("tools", "", {
                        name = item_name_overrides[""],
                        hidden = handdef._doc_items_hidden == true,
                        data = {
                                longdesc = help.longdesc[""],
                                usagehelp = help.usagehelp[""],
                                itemstring = "",
                                def = handdef,
                        }
                })
        end

        local add_entries = function(deftable, category_id)
                for id, def in pairs(deftable) do
                        local name, ld, uh, im
                        local forced = false
                        if def._doc_items_create_entry == true and def ~= nil then forced = true end
                        name = get_entry_name(id)
                        if not (((def.description == nil or def.description == "") and def._doc_items_entry_name == nil) or (def._doc_items_create_entry == false) or (suppressed[id] == true)) or forced then
                                if def._doc_items_longdesc then
                                        ld = def._doc_items_longdesc
                                end
                                if help.longdesc[id] ~= nil then
                                        ld = help.longdesc[id]
                                end
                                if def._doc_items_usagehelp then
                                        uh = def._doc_items_usagehelp
                                end
                                if help.usagehelp[id] ~= nil then
                                        uh = help.usagehelp[id]
                                end
                                if def._doc_items_image then
                                        im = def._doc_items_image
                                end
                                local hidden
                                if id == "air" or id == ""  then hidden = false end
                                if type(def._doc_items_hidden) == "boolean" then
                                        hidden = def._doc_items_hidden
                                end
                                local custom_image
                                name = scrub_newlines(name)
                                local infotable = {
                                        name = name,
                                        hidden = hidden,
                                        data = {
                                                longdesc = ld,
                                                usagehelp = uh,
                                                image = im,
                                                itemstring = id,
                                                def = def,
                                        }
                                }
                                doc.add_entry(category_id, id, infotable)
                        end
                end
        end

        -- Add node entries
        add_entries(minetest.registered_nodes, "nodes")

        -- Add tool entries
        add_entries(minetest.registered_tools, "tools")

        -- Add craftitem entries
        add_entries(minetest.registered_craftitems, "craftitems")
end

--[[ Reveal items as the player progresses through the game.
Items are revealed by:
* Digging, punching or placing node,
* Crafting
* Having item in inventory (not instantly revealed) ]]

local function reveal_item(playername, itemstring)
        local category_id
        if itemstring == nil or itemstring == "" or playername == nil or playername == "" then
                return false
        end
        if minetest.registered_nodes[itemstring] ~= nil then
                category_id = "nodes"
        elseif minetest.registered_tools[itemstring] ~= nil then
                category_id = "tools"
        elseif minetest.registered_craftitems[itemstring] ~= nil then
                category_id = "craftitems"
        elseif minetest.registered_items[itemstring] ~= nil then
                category_id = "craftitems"
        else
                return false
        end
        doc.mark_entry_as_revealed(playername, category_id, itemstring)
        return true
end

local function reveal_items_in_inventory(player)
        local inv = player:get_inventory()
        local list = inv:get_list("main")
        for l=1, #list do
                reveal_item(player:get_player_name(), list[l]:get_name())
        end
end

minetest.register_on_dignode(function(pos, oldnode, digger)
        if digger == nil then return end
        local playername = digger:get_player_name()
        if playername ~= nil and playername ~= "" and oldnode ~= nil then
                reveal_item(playername, oldnode.name)
                reveal_items_in_inventory(digger)
        end
end)

minetest.register_on_punchnode(function(pos, node, puncher, pointed_thing)
        if puncher == nil then return end
        local playername = puncher:get_player_name()
        if playername ~= nil and playername ~= "" and node ~= nil then
                reveal_item(playername, node.name)
        end
end)

minetest.register_on_placenode(function(pos, newnode, placer, oldnode, itemstack, pointed_thing)
        if placer == nil then return end
        local playername = placer:get_player_name()
        if playername ~= nil and playername ~= "" and itemstack ~= nil and not itemstack:is_empty() then
                reveal_item(playername, itemstack:get_name())
        end
end)

minetest.register_on_craft(function(itemstack, player, old_craft_grid, craft_inv)
        if player == nil then return end
        local playername = player:get_player_name()
        if playername ~= nil and playername ~= "" and itemstack ~= nil and not itemstack:is_empty() then
                reveal_item(playername, itemstack:get_name())
        end
end)

minetest.register_on_item_eat(function(hp_change, replace_with_item, itemstack, user, pointed_thing)
        if user == nil then return end
        local playername = user:get_player_name()
        if playername ~= nil and playername ~= "" and itemstack ~= nil and not itemstack:is_empty() then
                reveal_item(playername, itemstack:get_name())
                if replace_with_item ~= nil then
                        reveal_item(playername, replace_with_item)
                end
        end
end)

minetest.register_on_joinplayer(function(player)
        reveal_items_in_inventory(player)
end)

--[[ Periodically check all items in player inventory and reveal them all.
TODO: Check whether there's a serious performance impact on servers with many players.
TODO: If possible, try to replace this functionality by updating the revealed items as
      soon the player obtained a new item (probably needs new Minetest callbacks). ]]
local checktime = 8
local timer = 0
minetest.register_globalstep(function(dtime)
        timer = timer + dtime
        if timer > checktime then
                local players = minetest.get_connected_players()
                for p=1, #players do
                        reveal_items_in_inventory(players[p])
                end

                timer = math.fmod(timer, checktime)
        end
end)

minetest.after(0, gather_descs)