Use minetest.raillike_group for rails

[MineClone/MineClone2/MineClone2.git] / mods / HELP / mcl_craftguide / init.lua

mcl_craftguide = {}

local M = minetest
local player_data = {}

-- Caches
local init_items    = {}
local searches      = {}
local recipes_cache = {}
local usages_cache  = {}
local fuel_cache    = {}

local progressive_mode = M.settings:get_bool("mcl_craftguide_progressive_mode", true)
local sfinv_only = false

local colorize = M.colorize
local reg_items = M.registered_items
local get_result = M.get_craft_result
local show_formspec = M.show_formspec
local get_player_by_name = M.get_player_by_name
local serialize, deserialize = M.serialize, M.deserialize

local ESC = M.formspec_escape
local S = M.get_translator("mcl_craftguide")

local maxn, sort, concat, insert, copy =
        table.maxn, table.sort, table.concat, table.insert,
        table.copy

local fmt, find, gmatch, match, sub, split, lower =
        string.format, string.find, string.gmatch, string.match,
        string.sub, string.split, string.lower

local min, max, floor, ceil = math.min, math.max, math.floor, math.ceil
local pairs, next, unpack = pairs, next, unpack
local vec_add, vec_mul = vector.add, vector.multiply

local DEFAULT_SIZE = 10
local MIN_LIMIT, MAX_LIMIT = 10, 12
DEFAULT_SIZE = min(MAX_LIMIT, max(MIN_LIMIT, DEFAULT_SIZE))

local GRID_LIMIT = 5
local POLL_FREQ  = 0.25

local FMT = {
        box     = "box[%f,%f;%f,%f;%s]",
        label   = "label[%f,%f;%s]",
        image   = "image[%f,%f;%f,%f;%s]",
        button  = "button[%f,%f;%f,%f;%s;%s]",
        tooltip = "tooltip[%s;%s]",
        item_image = "item_image[%f,%f;%f,%f;%s]",
        image_button = "image_button[%f,%f;%f,%f;%s;%s;%s]",
        item_image_button = "item_image_button[%f,%f;%f,%f;%s;%s;%s]",
}

local group_stereotypes = {
        wood         = "mcl_core:wood",
        stone        = "mcl_core:stone",
        sand         = "mcl_core:sand",
        wool         = "mcl_wool:white",
        carpet       = "mcl_wool:white_carpet",
        dye          = "mcl_dye:red",
        water_bucket = "mcl_buckets:bucket_water",
        flower       = "mcl_flowers:dandelion",
        mushroom     = "mcl_mushrooms:mushroom_brown",
        wood_slab    = "mcl_stairs:slab_wood",
        wood_stairs  = "mcl_stairs:stairs_wood",
        coal         = "mcl_core:coal_lump",
        shulker_box  = "mcl_chests:violet_shulker_box",
        quartz_block = "mcl_nether:quartz_block",
        banner       = "mcl_banners:banner_item_white",
        mesecon_conductor_craftable = "mesecons:wire_00000000_off",
        purpur_block = "mcl_end:purpur_block",
        normal_sandstone = "mcl_core:sandstone",
        red_sandstone = "mcl_core:redsandstone",
        compass      = mcl_compass.stereotype,
        clock        = mcl_clock.sterotype,
}

local group_names = {
        shulker_box = S("Any shulker box"),
        wool = S("Any wool"),
        wood = S("Any wood planks"),
        tree = S("Any wood"),
        sand = S("Any sand"),
        normal_sandstone = S("Any normal sandstone"),
        red_sandstone = S("Any red sandstone"),
        carpet = S("Any carpet"),
        dye = S("Any dye"),
        water_bucket = S("Any water bucket"),
        flower = S("Any flower"),
        mushroom = S("Any mushroom"),
        wood_slab = S("Any wooden slab"),
        wood_stairs = S("Any wooden stairs"),
        coal = S("Any coal"),
        quartz_block = S("Any kind of quartz block"),
        purpur_block = S("Any kind of purpur block"),
        stonebrick = S("Any stone bricks"),
        stick = S("Any stick"),
}



local item_lists = {
        "main",
        "craft",
        "craftpreview",
}

local function table_merge(t, t2)
        t, t2 = t or {}, t2 or {}
        local c = #t

        for i = 1, #t2 do
                c = c + 1
                t[c] = t2[i]
        end

        return t
end

local function table_replace(t, val, new)
        for k, v in pairs(t) do
                if v == val then
                        t[k] = new
                end
        end
end

local function table_diff(t, t2)
        local hash = {}

        for i = 1, #t do
                local v = t[i]
                hash[v] = true
        end

        for i = 1, #t2 do
                local v = t2[i]
                hash[v] = nil
        end

        local diff, c = {}, 0

        for i = 1, #t do
                local v = t[i]
                if hash[v] then
                        c = c + 1
                        diff[c] = v
                end
        end

        return diff
end

local custom_crafts, craft_types = {}, {}

function mcl_craftguide.register_craft_type(name, def)
        local func = "mcl_craftguide.register_craft_guide(): "
        assert(name, func .. "'name' field missing")
        assert(def.description, func .. "'description' field missing")
        assert(def.icon, func .. "'icon' field missing")

        craft_types[name] = def
end

function mcl_craftguide.register_craft(def)
        local func = "mcl_craftguide.register_craft(): "
        assert(def.type, func .. "'type' field missing")
        assert(def.width, func .. "'width' field missing")
        assert(def.output, func .. "'output' field missing")
        assert(def.items, func .. "'items' field missing")

        custom_crafts[#custom_crafts + 1] = def
end

local recipe_filters = {}

function mcl_craftguide.add_recipe_filter(name, f)
        local func = "mcl_craftguide.add_recipe_filter(): "
        assert(name, func .. "filter name missing")
        assert(f and type(f) == "function", func .. "filter function missing")

        recipe_filters[name] = f
end

function mcl_craftguide.remove_recipe_filter(name)
        recipe_filters[name] = nil
end

function mcl_craftguide.set_recipe_filter(name, f)
        local func = "mcl_craftguide.set_recipe_filter(): "
        assert(name, func .. "filter name missing")
        assert(f and type(f) == "function", func .. "filter function missing")

        recipe_filters = {[name] = f}
end

function mcl_craftguide.get_recipe_filters()
        return recipe_filters
end

local function apply_recipe_filters(recipes, player)
        for _, filter in pairs(recipe_filters) do
                recipes = filter(recipes, player)
        end

        return recipes
end

local search_filters = {}

function mcl_craftguide.add_search_filter(name, f)
        local func = "mcl_craftguide.add_search_filter(): "
        assert(name, func .. "filter name missing")
        assert(f and type(f) == "function", func .. "filter function missing")

        search_filters[name] = f
end

function mcl_craftguide.remove_search_filter(name)
        search_filters[name] = nil
end

function mcl_craftguide.get_search_filters()
        return search_filters
end

local formspec_elements = {}

function mcl_craftguide.add_formspec_element(name, def)
        local func = "mcl_craftguide.add_formspec_element(): "
        assert(def.element, func .. "'element' field not defined")
        assert(def.type, func .. "'type' field not defined")
        assert(FMT[def.type], func .. "'" .. def.type .. "' type not supported by the API")

        formspec_elements[name] = {
                type    = def.type,
                element = def.element,
                action  = def.action,
        }
end

function mcl_craftguide.remove_formspec_element(name)
        formspec_elements[name] = nil
end

function mcl_craftguide.get_formspec_elements()
        return formspec_elements
end

local function item_has_groups(item_groups, groups)
        for i = 1, #groups do
                local group = groups[i]
                if not item_groups[group] then
                        return
                end
        end

        return true
end

local function extract_groups(str)
        return split(sub(str, 7), ",")
end

local function item_in_recipe(item, recipe)
        for _, recipe_item in pairs(recipe.items) do
                if recipe_item == item then
                        return true
                end
        end
end

local function groups_item_in_recipe(item, recipe)
        local item_groups = reg_items[item].groups
        for _, recipe_item in pairs(recipe.items) do
                if sub(recipe_item, 1, 6) == "group:" then
                        local groups = extract_groups(recipe_item)
                        if item_has_groups(item_groups, groups) then
                                local usage = copy(recipe)
                                table_replace(usage.items, recipe_item, item)
                                return usage
                        end
                end
        end
end

local function get_item_usages(item)
        local usages, c = {}, 0

        for _, recipes in pairs(recipes_cache) do
        for i = 1, #recipes do
                local recipe = recipes[i]
                if item_in_recipe(item, recipe) then
                        c = c + 1
                        usages[c] = recipe
                else
                        recipe = groups_item_in_recipe(item, recipe)
                        if recipe then
                                c = c + 1
                                usages[c] = recipe
                        end
                end
        end
        end

        if fuel_cache[item] then
                usages[#usages + 1] = {type = "fuel", width = 1, items = {item}}
        end

        return usages
end

local function get_filtered_items(player)
        local items, c = {}, 0

        for i = 1, #init_items do
                local item = init_items[i]
                local recipes = recipes_cache[item]
                local usages = usages_cache[item]

                if recipes and #apply_recipe_filters(recipes, player) > 0 or
                   usages and #apply_recipe_filters(usages, player) > 0 then
                        c = c + 1
                        items[c] = item
                end
        end

        return items
end

local function cache_recipes(output)
        local recipes = M.get_all_craft_recipes(output) or {}
        local c = 0

        for i = 1, #custom_crafts do
                local custom_craft = custom_crafts[i]
                if match(custom_craft.output, "%S*") == output then
                        c = c + 1
                        recipes[c] = custom_craft
                end
        end

        if #recipes > 0 then
                recipes_cache[output] = recipes
                return true
        end
end

local function get_recipes(item, data, player)
        local recipes = recipes_cache[item]
        local usages = usages_cache[item]

        if recipes then
                recipes = apply_recipe_filters(recipes, player)
        end

        local no_recipes = not recipes or #recipes == 0
        if no_recipes and not usages then
                return
        elseif usages and no_recipes then
                data.show_usages = true
        end

        if data.show_usages then
                recipes = apply_recipe_filters(usages_cache[item], player)
                if #recipes == 0 then
                        return
                end
        end

        return recipes
end

local function get_burntime(item)
        return get_result({method = "fuel", width = 1, items = {item}}).time
end

local function cache_fuel(item)
        local burntime = get_burntime(item)
        if burntime > 0 then
                fuel_cache[item] = burntime
                return true
        end
end

local function groups_to_item(groups)
        if #groups == 1 then
                local group = groups[1]
                local def_gr = "mcl_core:" .. group

                if group_stereotypes[group] then
                        return group_stereotypes[group]
                elseif reg_items[def_gr] then
                        return def_gr
                end
        end

        for name, def in pairs(reg_items) do
                if item_has_groups(def.groups, groups) then
                        return name
                end
        end

        return ""
end

local function get_tooltip(item, groups, cooktime, burntime)
        local tooltip

        if groups then
                local gcol = "#FFAAFF"
                if #groups == 1 then
                        local g = group_names[groups[1]]
                        -- Treat the groups “compass” and “clock” as fake groups
                        -- and just print the normal item name without special formatting
                        if groups[1] == "compass" or groups[1] == "clock" then
                                groupstr = reg_items[item].description
                        elseif group_names[groups[1]] then
                                -- Use the special group name string
                                groupstr = minetest.colorize(gcol, group_names[groups[1]])
                        else
                                --[[ Fallback: Generic group explanation: This always
                                works, but the internally used group name (which
                                looks ugly) is exposed to the user. ]]
                                groupstr = minetest.colorize(gcol, groups[1])
                                groupstr = S("Any item belonging to the @1 group", groupstr)
                        end
                        tooltip = groupstr
                else

                        local groupstr, c = {}, 0
                        for i = 1, #groups do
                                c = c + 1
                                groupstr[c] = colorize(gcol, groups[i])
                        end

                        groupstr = concat(groupstr, ", ")
                        tooltip = S("Any item belonging to the groups: @1", groupstr)
                end
        else
                tooltip = reg_items[item].description
        end

        if cooktime then
                tooltip = tooltip .. "\n" ..
                        S("Cooking time: @1", colorize("yellow", cooktime))
        end

        if burntime then
                tooltip = tooltip .. "\n" ..
                        S("Burning time: @1", colorize("yellow", burntime))
        end

        return fmt(FMT.tooltip, item, ESC(tooltip))
end

local function get_recipe_fs(data, iY)
        local fs = {}
        local recipe = data.recipes[data.rnum]
        local width = recipe.width
        local xoffset = data.iX / 2.15
        local cooktime, shapeless

        if recipe.type == "cooking" then
                cooktime, width = width, 1
        elseif width == 0 then
                shapeless = true
                if #recipe.items <= 4 then
                        width = 2
                else
                        width = min(3, #recipe.items)
                end
        end

        local rows = ceil(maxn(recipe.items) / width)
        local rightest, btn_size, s_btn_size = 0, 1.1

        local btn_lab = data.show_usages and
                ESC(S("Usage @1 of @2", data.rnum, #data.recipes)) or
                ESC(S("Recipe @1 of @2", data.rnum, #data.recipes))

        fs[#fs + 1] = fmt(FMT.button,
                sfinv_only and 5.8 or data.iX - 2.6,
                sfinv_only and 7.9 or iY + 3.3,
                2.2,
                1,
                "alternate",
                btn_lab)

        if width > GRID_LIMIT or rows > GRID_LIMIT then
                fs[#fs + 1] = fmt(FMT.label,
                        (data.iX / 2) - 2,
                        iY + 2.2,
                        ESC(S("Recipe is too big to be displayed (@1×@2)", width, rows)))

                return concat(fs)
        end

        for i, item in pairs(recipe.items) do
                local X = ceil((i - 1) % width + xoffset - width) -
                        (sfinv_only and 0 or 0.2)
                local Y = ceil(i / width + (iY + 2) - min(2, rows))

                if width > 3 or rows > 3 then
                        btn_size = width > 3 and 3 / width or 3 / rows
                        s_btn_size = btn_size
                        X = btn_size * (i % width) + xoffset - 2.65
                        Y = btn_size * floor((i - 1) / width) + (iY + 3) - min(2, rows)
                end

                if X > rightest then
                        rightest = X
                end

                local groups
                if sub(item, 1, 6) == "group:" then
                        groups = extract_groups(item)
                        item = groups_to_item(groups)
                end

                local label = ""
                if groups and (#groups >= 1 and groups[1] ~= "compass" and groups[1] ~= "clock") then
                        label = "\nG"
                end

                fs[#fs + 1] = fmt(FMT.item_image_button,
                        X,
                        Y + (sfinv_only and 0.7 or 0.2),
                        btn_size,
                        btn_size,
                        item,
                        match(item, "%S*"),
                        ESC(label))

                local burntime = fuel_cache[item]

                if groups or cooktime or burntime then
                        fs[#fs + 1] = get_tooltip(item, groups, cooktime, burntime)
                end
        end

        local custom_recipe = craft_types[recipe.type]

        if custom_recipe or shapeless or recipe.type == "cooking" then
                local icon = custom_recipe and custom_recipe.icon or
                             shapeless and "shapeless" or "furnace"

                if recipe.type == "cooking" then
                        icon = "default_furnace_front_active.png"
                elseif not custom_recipe then
                        icon = fmt("craftguide_%s.png", icon)
                end

                fs[#fs + 1] = fmt(FMT.image,
                        rightest + 1.2,
                        sfinv_only and 6.2 or iY + 1.7,
                        0.5,
                        0.5,
                        icon)

                local tooltip = custom_recipe and custom_recipe.description or
                                shapeless and S("Shapeless") or S("Cooking")

                fs[#fs + 1] = fmt("tooltip[%f,%f;%f,%f;%s]",
                        rightest + 1.2,
                        sfinv_only and 6.2 or iY + 1.7,
                        0.5,
                        0.5,
                        ESC(tooltip))
        end

        local arrow_X  = rightest + (s_btn_size or 1.1)
        local output_X = arrow_X + 0.9

        fs[#fs + 1] = fmt(FMT.image,
                arrow_X,
                sfinv_only and 6.85 or iY + 2.35,
                0.9,
                0.7,
                "craftguide_arrow.png")

        if recipe.type == "fuel" then
                fs[#fs + 1] = fmt(FMT.image,
                        output_X,
                        sfinv_only and 6.68 or iY + 2.18,
                        1.1,
                        1.1,
                        "mcl_craftguide_fuel.png")
        else
                local output_name = match(recipe.output, "%S+")
                local burntime = fuel_cache[output_name]

                fs[#fs + 1] = fmt(FMT.item_image_button,
                        output_X,
                        sfinv_only and 6.7 or iY + 2.2,
                        1.1,
                        1.1,
                        recipe.output,
                        ESC(output_name),
                        "")

                if burntime then
                        fs[#fs + 1] = get_tooltip(output_name, nil, nil, burntime)

                        fs[#fs + 1] = fmt(FMT.image,
                                output_X + 1,
                                sfinv_only and 6.83 or iY + 2.33,
                                0.6,
                                0.4,
                                "craftguide_arrow.png")

                        fs[#fs + 1] = fmt(FMT.image,
                                output_X + 1.6,
                                sfinv_only and 6.68 or iY + 2.18,
                                0.6,
                                0.6,
                                "mcl_craftguide_fuel.png")
                end
        end

        return concat(fs)
end

local function make_formspec(name)
        local data = player_data[name]
        local iY = sfinv_only and 4 or data.iX - 5
        local ipp = data.iX * iY

        data.pagemax = max(1, ceil(#data.items / ipp))

        local fs = {}

        if not sfinv_only then
                fs[#fs + 1] = fmt("size[%f,%f;]", data.iX - 0.35, iY + 4)

                fs[#fs + 1] = [[
                        background[1,1;1,1;craftguide_bg.png;true]
                ]]

                fs[#fs + 1] = fmt([[ tooltip[size_inc;%s]
                                     tooltip[size_dec;%s] ]],
                        ESC(S("Increase window size")),
                        ESC(S("Decrease window size")))

                fs[#fs + 1] = fmt([[
                        image_button[%f,0.12;0.8,0.8;craftguide_zoomin_icon.png;size_inc;]
                        image_button[%f,0.12;0.8,0.8;craftguide_zoomout_icon.png;size_dec;] ]],
                        data.iX * 0.47,
                        data.iX * 0.47 + 0.6)
        end

        fs[#fs + 1] = [[
                image_button[2.4,0.12;0.8,0.8;craftguide_search_icon.png;search;]
                image_button[3.05,0.12;0.8,0.8;craftguide_clear_icon.png;clear;]
                field_close_on_enter[filter;false]
        ]]

        fs[#fs + 1] = fmt([[ tooltip[search;%s]
                             tooltip[clear;%s]
                             tooltip[prev;%s]
                             tooltip[next;%s] ]],
                ESC(S("Search")),
                ESC(S("Reset")),
                ESC(S("Previous page")),
                ESC(S("Next page")))

        fs[#fs + 1] = fmt("label[%f,%f;%s / %u]",
                sfinv_only and 6.3 or data.iX - 2.2,
                0.22,
                colorize("yellow", data.pagenum),
                data.pagemax)

        fs[#fs + 1] = fmt([[
                image_button[%f,0.12;0.8,0.8;craftguide_prev_icon.png;prev;]
                image_button[%f,0.12;0.8,0.8;craftguide_next_icon.png;next;] ]],
                sfinv_only and 5.5 or data.iX - 3.1,
                sfinv_only and 7.3 or (data.iX - 1.2) - (data.iX >= 11 and 0.08 or 0))

        fs[#fs + 1] = fmt("field[0.3,0.32;2.5,1;filter;;%s]", ESC(data.filter))

        if #data.items == 0 then
                local no_item = S("No item to show")
                local pos = (data.iX / 2) - 1

                if next(recipe_filters) and #init_items > 0 and data.filter == "" then
                        no_item = S("Collect items to reveal more recipes")
                        pos = pos - 1
                end

                fs[#fs + 1] = fmt(FMT.label, pos, 2, ESC(no_item))
        end

        local first_item = (data.pagenum - 1) * ipp
        for i = first_item, first_item + ipp - 1 do
                local item = data.items[i + 1]
                if not item then
                        break
                end

                local X = i % data.iX
                local Y = (i % ipp - X) / data.iX + 1

                fs[#fs + 1] = fmt("item_image_button[%f,%f;%f,%f;%s;%s_inv;]",
                        X - (sfinv_only and 0 or (X * 0.05)),
                        Y,
                        1.1,
                        1.1,
                        item,
                        item)
        end

        if data.recipes and #data.recipes > 0 then
                fs[#fs + 1] = get_recipe_fs(data, iY)
        end

        for elem_name, def in pairs(formspec_elements) do
                local element = def.element(data)
                if element then
                        if find(def.type, "button") then
                                insert(element, #element, elem_name)
                        end

                        fs[#fs + 1] = fmt(FMT[def.type], unpack(element))
                end
        end

        return concat(fs)
end

local show_fs = function(player, name)
        if sfinv_only then
                sfinv.set_player_inventory_formspec(player)
        else
                show_formspec(name, "mcl_craftguide", make_formspec(name))
        end
end

mcl_craftguide.add_search_filter("groups", function(item, groups)
        local itemdef = reg_items[item]
        local has_groups = true

        for i = 1, #groups do
                local group = groups[i]
                if not itemdef.groups[group] then
                        has_groups = nil
                        break
                end
        end

        return has_groups
end)

local function search(data)
        local filter = data.filter

        if searches[filter] then
                data.items = searches[filter]
                return
        end

        local filtered_list, c = {}, 0
        local extras = "^(.-)%+([%w_]+)=([%w_,]+)"
        local search_filter = next(search_filters) and match(filter, extras)
        local filters = {}

        if search_filter then
                for filter_name, values in gmatch(filter, sub(extras, 6, -1)) do
                        if search_filters[filter_name] then
                                values = split(values, ",")
                                filters[filter_name] = values
                        end
                end
        end

        for i = 1, #data.items_raw do
                local item = data.items_raw[i]
                local def  = reg_items[item]
                local desc = lower(def.description)
                local search_in = item .. desc
                local to_add

                if search_filter then
                        for filter_name, values in pairs(filters) do
                                local func = search_filters[filter_name]
                                to_add = func(item, values) and (search_filter == "" or
                                        find(search_in, search_filter, 1, true))
                        end
                else
                        to_add = find(search_in, filter, 1, true)
                end

                if to_add then
                        c = c + 1
                        filtered_list[c] = item
                end
        end

        if not next(recipe_filters) then
                -- Cache the results only if searched 2 times
                if searches[filter] == nil then
                        searches[filter] = false
                else
                        searches[filter] = filtered_list
                end
        end

        data.items = filtered_list
end

local function get_inv_items(player)
        local inv = player:get_inventory()
        local stacks = {}

        for i = 1, #item_lists do
                local list = inv:get_list(item_lists[i])
                table_merge(stacks, list)
        end

        local inv_items, c = {}, 0

        for i = 1, #stacks do
                local stack = stacks[i]
                if not stack:is_empty() then
                        local name = stack:get_name()
                        if reg_items[name] then
                                c = c + 1
                                inv_items[c] = name
                        end
                end
        end

        return inv_items
end

local function init_data(name)
        player_data[name] = {
                filter  = "",
                pagenum = 1,
                iX      = sfinv_only and 8 or DEFAULT_SIZE,
                items   = init_items,
                items_raw = init_items,
        }
end

local function reset_data(data)
        data.filter      = ""
        data.pagenum     = 1
        data.rnum        = 1
        data.query_item  = nil
        data.show_usages = nil
        data.recipes     = nil
        data.items       = data.items_raw
end

local function cache_usages()
        for i = 1, #init_items do
                local item = init_items[i]
                usages_cache[item] = get_item_usages(item)
        end
end

local function get_init_items()
        local c = 0
        for name, def in pairs(reg_items) do
                local is_fuel = cache_fuel(name)
                if not (def.groups.not_in_craft_guide == 1 or
                                def.groups.not_in_creative_inventory == 1) and
                                def.description and def.description ~= "" and
                                (cache_recipes(name) or is_fuel) then
                        c = c + 1
                        init_items[c] = name
                end
        end

        sort(init_items)
        cache_usages()
end

local function on_receive_fields(player, fields)
        local name = player:get_player_name()
        local data = player_data[name]

        for elem_name, def in pairs(formspec_elements) do
                if fields[elem_name] and def.action then
                        return def.action(player, data)
                end
        end

        if fields.clear then
                reset_data(data)
                show_fs(player, name)

        elseif fields.alternate then
                if #data.recipes == 1 then
                        return
                end

                local num_next = data.rnum + 1
                data.rnum = data.recipes[num_next] and num_next or 1
                show_fs(player, name)

        elseif (fields.key_enter_field == "filter" or fields.search) and
                        fields.filter ~= "" then
                local fltr = lower(fields.filter)
                if data.filter == fltr then
                        return
                end

                data.filter = fltr
                data.pagenum = 1
                search(data)
                show_fs(player, name)

        elseif fields.prev or fields.next then
                if data.pagemax == 1 then
                        return
                end

                data.pagenum = data.pagenum - (fields.prev and 1 or -1)

                if data.pagenum > data.pagemax then
                        data.pagenum = 1
                elseif data.pagenum == 0 then
                        data.pagenum = data.pagemax
                end

                show_fs(player, name)

        elseif (fields.size_inc and data.iX < MAX_LIMIT) or
                        (fields.size_dec and data.iX > MIN_LIMIT) then
                data.pagenum = 1
                data.iX = data.iX + (fields.size_inc and 1 or -1)
                show_fs(player, name)
        else
                local item
                for field in pairs(fields) do
                        if find(field, ":") then
                                item = field
                                break
                        end
                end

                if not item then
                        return
                elseif sub(item, -4) == "_inv" then
                        item = sub(item, 1, -5)
                end

                if item ~= data.query_item then
                        data.show_usages = nil
                else
                        data.show_usages = not data.show_usages
                end

                local recipes = get_recipes(item, data, player)
                if not recipes then
                        return
                end

                data.query_item = item
                data.recipes    = recipes
                data.rnum       = 1

                show_fs(player, name)
        end
end

M.register_on_mods_loaded(get_init_items)

-- TODO: Remove sfinv support
if sfinv_only then
        sfinv.register_page("craftguide:craftguide", {
                title = "Craft Guide",

                get = function(self, player, context)
                        local name = player:get_player_name()
                        local formspec = make_formspec(name)

                        return sfinv.make_formspec(player, context, formspec)
                end,

                on_enter = function(self, player, context)
                        if next(recipe_filters) then
                                local name = player:get_player_name()
                                local data = player_data[name]

                                data.items_raw = get_filtered_items(player)
                                search(data)
                        end
                end,

                on_player_receive_fields = function(self, player, context, fields)
                        on_receive_fields(player, fields)
                end,
        })
else
        M.register_on_player_receive_fields(function(player, formname, fields)
                if formname == "mcl_craftguide" then
                        on_receive_fields(player, fields)
                elseif fields.__mcl_craftguide then
                        mcl_craftguide.show(player:get_player_name())
                end
        end)

        local function on_use(user)
                local name = user:get_player_name()

                if next(recipe_filters) then
                        local data = player_data[name]
                        data.items_raw = get_filtered_items(user)
                        search(data)
                end

                show_formspec(name, "mcl_craftguide", make_formspec(name))
        end

end

if progressive_mode then
        local function item_in_inv(item, inv_items)
                local inv_items_size = #inv_items

                if sub(item, 1, 6) == "group:" then
                        local groups = extract_groups(item)
                        for i = 1, inv_items_size do
                                local inv_item = reg_items[inv_items[i]]
                                if inv_item then
                                        local item_groups = inv_item.groups
                                        if item_has_groups(item_groups, groups) then
                                                return true
                                        end
                                end
                        end
                else
                        for i = 1, inv_items_size do
                                if inv_items[i] == item then
                                        return true
                                end
                        end
                end
        end

        local function recipe_in_inv(recipe, inv_items)
                for _, item in pairs(recipe.items) do
                        if not item_in_inv(item, inv_items) then
                                return
                        end
                end

                return true
        end

        local function progressive_filter(recipes, player)
                local name = player:get_player_name()
                local data = player_data[name]

                if #data.inv_items == 0 then
                        return {}
                end

                local filtered, c = {}, 0
                for i = 1, #recipes do
                        local recipe = recipes[i]
                        if recipe_in_inv(recipe, data.inv_items) then
                                c = c + 1
                                filtered[c] = recipe
                        end
                end

                return filtered
        end

        -- Workaround. Need an engine call to detect when the contents
        -- of the player inventory changed, instead.
        local function poll_new_items()
                local players = M.get_connected_players()
                for i = 1, #players do
                        local player = players[i]
                        local name   = player:get_player_name()
                        local data   = player_data[name]
                        local inv_items = get_inv_items(player)
                        local diff      = table_diff(inv_items, data.inv_items)

                        if #diff > 0 then
                                data.inv_items = table_merge(diff, data.inv_items)
                        end
                end

                M.after(POLL_FREQ, poll_new_items)
        end

        poll_new_items()

        mcl_craftguide.add_recipe_filter("Default progressive filter", progressive_filter)

        M.register_on_joinplayer(function(player)
                local name = player:get_player_name()
                init_data(name)
                local meta = player:get_meta()
                local name = player:get_player_name()
                local data = player_data[name]

                data.inv_items = deserialize(meta:get_string("inv_items")) or {}
        end)

        local function save_meta(player)
                local meta = player:get_meta()
                local name = player:get_player_name()
                local data = player_data[name]

                meta:set_string("inv_items", serialize(data.inv_items))
        end

        M.register_on_leaveplayer(function(player)
                save_meta(player)
                local name = player:get_player_name()
                player_data[name] = nil
        end)

        M.register_on_shutdown(function()
                local players = M.get_connected_players()
                for i = 1, #players do
                        local player = players[i]
                        save_meta(player)
                end
        end)
else
        M.register_on_joinplayer(function(player)
                local name = player:get_player_name()
                init_data(name)
        end)

        M.register_on_leaveplayer(function(player)
                local name = player:get_player_name()
                player_data[name] = nil
        end)
end

function mcl_craftguide.show(name)
        local player = minetest.get_player_by_name(name)
        if next(recipe_filters) then
                local data = player_data[name]
                data.items_raw = get_filtered_items(player)
                search(data)
        end
        show_formspec(name, "mcl_craftguide", make_formspec(name))
end

--[[ Custom recipes (>3x3) test code

M.register_craftitem(":secretstuff:custom_recipe_test", {
        description = "Custom Recipe Test",
})

local cr = {}
for x = 1, 6 do
        cr[x] = {}
        for i = 1, 10 - x do
                cr[x][i] = {}
                for j = 1, 10 - x do
                        cr[x][i][j] = "group:wood"
                end
        end

        M.register_craft({
                output = "secretstuff:custom_recipe_test",
                recipe = cr[x]
        })
end
]]