Move around some group code and make the craftguide render well without a recipe

This also keeps recipes aligned to the right, close to the arrow.
It also calculates the craft's height.

1 files changed, 55 insertions, 112 deletions

diff --git a/register.lua b/register.lua
index 31b12ae..a471e2b 100644
--- a/register.lua
+++ b/register.lua
@@ -134,106 +134,39 @@ unified_inventory.register_page("craft", {
 	end,
 })
 
--- group_representative_item(): select representative item for a group
---
--- This is used when displaying craft recipes, where an ingredient is
--- specified by group rather than as a specific item.  A single-item group
--- is represented by that item, with the single-item status signalled
--- so that stack_image_button() can treat it as just the item.  If the
--- group contains no items at all, it will be treated as containing a
--- single unknown item.
---
--- Within a multiple-item group, we prefer to use an item that has the
--- same specific name as the group, and if there are more than one of
--- those items we prefer the one specified by the default mod if there
--- is one.  If this produces a bad result, the mod defining a group can
--- register its preference for which item should represent the group,
--- and we'll use that instead if possible.  Also, for a handful of groups
--- (predating this registration system) we have built-in preferences
--- that are used like registered preferences.  Among equally-preferred
--- items, we just pick the one with the lexicographically earliest name,
--- for determinism.
-local builtin_group_representative_items = {
-	mesecon_conductor_craftable = "mesecons:wire_00000000_off",
-	stone = "default:cobble",
-	wool = "wool:white",
-}
-local function compute_group_representative_item(groupspec)
-	local groupname = string.sub(groupspec, 7)
-	local candidate_items = {}
-	for itemname, itemdef in pairs(minetest.registered_items) do
-		if (itemdef.groups.not_in_creative_inventory or 0) == 0 and (itemdef.groups[groupname] or 0) ~= 0 then
-			table.insert(candidate_items, itemname)
-		end
-	end
-	if #candidate_items == 0 then return { item = "unobtainium!", sole = true } end
-	if #candidate_items == 1 then return { item = candidate_items[1], sole = true } end
-	local bestitem = ""
-	local bestpref = 0
-	for _, item in ipairs(candidate_items) do
-		local pref
-		if item == unified_inventory.registered_group_representative_items[groupname] then
-			pref = 5
-		elseif item == builtin_group_representative_items[groupname] then
-			pref = 4
-		elseif item == "default:"..groupname then
-			pref = 3
-		elseif item:gsub("^[^:]*:", "") == groupname then
-			pref = 2
-		else
-			pref = 1
-		end
-		if pref > bestpref or (pref == bestpref and item < bestitem) then
-			bestitem = item
-			bestpref = pref
-		end
-	end
-	return { item = bestitem, sole = false }
-end
-local group_representative_item_cache = {}
-local function group_representative_item(groupspec)
-	if not group_representative_item_cache[groupspec] then
-		group_representative_item_cache[groupspec] = compute_group_representative_item(groupspec)
-	end
-	return group_representative_item_cache[groupspec]
-end
 
 -- stack_image_button(): generate a form button displaying a stack of items
 --
 -- Normally a simple item_image_button[] is used.  If the stack contains
 -- more than one item, item_image_button[] doesn't have an option to
 -- display an item count in the way that an inventory slot does, so
--- we have to fake it using the label facility.  This doesn't let us
--- specify that the count should appear at bottom right, so we use some
--- dodgy whitespace to shift it away from the centre of the button.
--- Unfortunately the correct amount of whitespace depends on display
--- resolution, so the results from this will be variable.  This should be
--- replaced as soon as the engine adds support for a proper item count,
--- or at least label placement control, on buttons.
+-- we have to fake it using the label facility.
 --
 -- The specified item may be a group.  In that case, the group will be
 -- represented by some item in the group, along with a flag indicating
 -- that it's a group.  If the group contains only one item, it will be
 -- treated as if that item had been specified directly.
-local function stack_image_button(x, y, w, h, buttonname_prefix, stackstring)
-	local st = ItemStack(stackstring)
-	local specitem = st:get_name()
-	local c = st:get_count()
-	local clab = c == 1 and "       " or string.format("%7d", c)
-	local gflag, displayitem, selectitem
-	if string.sub(specitem, 1, 6) == "group:" then
-		local gri = group_representative_item(specitem)
-		gflag = not gri.sole
-		displayitem = gri.item
-		selectitem = gri.sole and gri.item or specitem
-	else
-		gflag = false
-		displayitem = specitem
-		selectitem = specitem
+
+local function stack_image_button(x, y, w, h, buttonname_prefix, item)
+	local name = item:get_name()
+	local count = item:get_count()
+	local show_is_group = false
+	local displayitem = name
+	local selectitem = name
+	if name:sub(1, 6) == "group:" then
+		local group_name = name:sub(7)
+		local group_item = unified_inventory.get_group_item(group_name)
+		show_group = not group_item.sole
+		displayitem = group_item.item or "unknown"
+		selectitem = group_item.sole and displayitem or name
 	end
-	local label = string.format("\n\n%s%7d", gflag and "G" or "  ", c):gsub(" 1$", " .")
-	if label == "\n\n        ." then label = "" end
-	return "item_image_button["..x..","..y..";"..w..","..h..";"..minetest.formspec_escape(displayitem)..";"..minetest.formspec_escape(buttonname_prefix..selectitem)..";"..label.."]"
+	-- Hackily shift the count to the bottom right
+	local shiftstr = "\n\n        "
+	return string.format("item_image_button[%u,%u;%u,%u;%s;%s;%s]",
+			x, y, w, h,
+			minetest.formspec_escape(displayitem),
+			minetest.formspec_escape(buttonname_prefix..selectitem),
+			count ~= 1 and shiftstr..tostring(count) or "")
 end
 
 unified_inventory.register_page("craftguide", {
@@ -241,14 +174,15 @@ unified_inventory.register_page("craftguide", {
 		local player_name = player:get_player_name()
 		local formspec = ""
 		formspec = formspec.."background[0,4.5;8,4;ui_main_inventory.png]"
+		formspec = formspec.."background[0,1;8,3;ui_craftguide_form.png]"
 		formspec = formspec.."label[0,0;Crafting Guide]"
 		formspec = formspec.."listcolors[#00000000;#00000000]"
 		local craftinv = minetest.get_inventory({
 			type = "detached",
 			name = player_name.."craftrecipe"
 		})
-		local item_name = unified_inventory.current_item[player_name]
-		if not item_name then return {formspec=formspec} end
+		local item_name = unified_inventory.current_item[player_name] or ""
+
 		formspec = formspec.."textarea[0.3,0.6;10,1;;Result: "..minetest.formspec_escape(item_name)..";]"
 		formspec = formspec.."list[detached:"..minetest.formspec_escape(player_name).."craftrecipe;output;6,1;1,1;]"
 
@@ -259,38 +193,47 @@ unified_inventory.register_page("craftguide", {
 			alternates = #crafts
 			craft = crafts[alternate]
 		end
-		if not craft then
+
+		if craft then
+			craftinv:set_stack("output", 1, craft.output)
+			craft_type = unified_inventory.registered_craft_types[craft.type] or
+					unified_inventory.craft_type_defaults(craft.type, {})
+			formspec = formspec.."label[6,3.35;Method:]"
+			formspec = formspec.."label[6,3.75;"
+					..minetest.formspec_escape(craft_type.description).."]"
+		else
 			craftinv:set_stack("output", 1, item_name)
+			craft_type = unified_inventory.craft_type_defaults("", {})
 			formspec = formspec.."label[6,3.35;No recipes]"
-			return {formspec=formspec}
-		end
-
-		formspec = formspec.."background[0,1;8,3;ui_craftguide_form.png]"
-		craft_type = unified_inventory.registered_craft_types[craft.type] or unified_inventory.canonicalise_craft_type(craft.type, {})
-		formspec = formspec.."label[6,3.35;Method:]"
-		formspec = formspec.."label[6,3.75;"..minetest.formspec_escape(craft_type.description).."]"
-		craftinv:set_stack("output", 1, craft.output)
-
-		-- fake buttons just to make grid
-		for y = 1, craft_type.height do
-		for x = 1, craft_type.width do
-			formspec = formspec.."image_button["
-				..(1.0 + x)..","..(0.0 + y)..";1.1,1.1;ui_blank_image.png;;]"
-		end
 		end
 
-		local width = craft.width
+		local width = craft and craft.width or 0
 		if width == 0 then
 			-- Shapeless recipe
 			width = craft_type.width
 		end
 
+		local height = craft_type.height
+		if craft then
+			height = math.ceil(table.maxn(craft.items) / width)
+		end
+
 		local i = 1
-		for y = 1, craft_type.height do
+		-- This keeps recipes aligned to the right,
+		-- so that they're close to the arrow.
+		local xoffset = 1 + (3 - width)
+		for y = 1, height do
 		for x = 1, width do
-			local item = craft.items[i]
+			local item = craft and craft.items[i]
 			if item then
-				formspec = formspec..stack_image_button(1.0+x, 0.0+y, 1.1, 1.1, "item_button_", item)
+				formspec = formspec..stack_image_button(
+						xoffset + x, y, 1.1, 1.1,
+						"item_button_", ItemStack(item))
+			else
+				-- Fake buttons just to make grid
+				formspec = formspec.."image_button["
+					..tostring(xoffset + x)..","..tostring(y)
+					..";1,1;ui_blank_image.png;;]"
 			end
 			i = i + 1
 		end
@@ -303,13 +246,13 @@ unified_inventory.register_page("craftguide", {
 					.."button[7.2,2.5;0.6,0.5;craftguide_craft_max;All]"
 		end
 
-		if alternates > 1 then
+		if alternates and alternates > 1 then
 			formspec = formspec.."label[0,2.6;Recipe "
 					..tostring(alternate).." of "
 					..tostring(alternates).."]"
 					.."button[0,3.15;2,1;alternate;Alternate]"
 		end
-		return {formspec=formspec}
+		return {formspec = formspec}
 	end,
 })