Show title and author of book in description

Utilizes the new key-meta (as with nodes) and the ability to set the description of an itemstack with the `description` meta key. Includes code to convert old metadata to new key-meta.

mods/default/craftitems.lua

@@ -15,11 +15,19 @@ minetest.register_craftitem("default:paper", {
 local lpp = 14 -- Lines per book's page
 local function book_on_use(itemstack, user)
 	local player_name = user:get_player_name()
-	local data = minetest.deserialize(itemstack:get_metadata())
+	local meta = itemstack:get_meta()
 	local title, text, owner = "", "", player_name
 	local page, page_max, lines, string = 1, 1, {}, ""
 
-	if data then
+	-- Backwards compatibility
+	local old_data = minetest.deserialize(itemstack:get_metadata())
+	if old_data then
+		meta:from_table({ fields = old_data })
+	end
+
+	local data = meta:to_table().fields
+
+	if data.owner then
 		title = data.title
 		text = data.text
 		owner = data.owner
@@ -81,35 +89,38 @@ minetest.register_on_player_receive_fields(function(player, formname, fields)
 				new_stack = ItemStack("default:book_written")
 			end
 		else
-			data = minetest.deserialize(stack:get_metadata())
+			data = stack:get_meta():to_table().fields
 		end
 
 		if not data then data = {} end
 		data.title = fields.title
+		data.owner = player:get_player_name()
+		data.description = "\""..fields.title.."\" by "..data.owner
 		data.text = fields.text
 		data.text_len = #data.text
 		data.page = 1
 		data.page_max = math.ceil((#data.text:gsub("[^\n]", "") + 1) / lpp)
-		data.owner = player:get_player_name()
-		local data_str = minetest.serialize(data)
 
 		if new_stack then
-			new_stack:set_metadata(data_str)
+			new_stack:get_meta():from_table({ fields = data })
 			if inv:room_for_item("main", new_stack) then
 				inv:add_item("main", new_stack)
 			else
 				minetest.add_item(player:getpos(), new_stack)
 			end
 		else
-			stack:set_metadata(data_str)
+			stack:get_meta():from_table({ fields = data })
 		end
 
 	elseif fields.book_next or fields.book_prev then
-		local data = minetest.deserialize(stack:get_metadata())
+		local data = stack:get_meta():to_table().fields
 		if not data or not data.page then
 			return
 		end
 
+		data.page = tonumber(data.page)
+		data.page_max = tonumber(data.page_max)
+
 		if fields.book_next then
 			data.page = data.page + 1
 			if data.page > data.page_max then
@@ -249,4 +260,3 @@ minetest.register_craftitem("default:flint", {
 	description = "Flint",
 	inventory_image = "default_flint.png"
 })
-