Add category series.

These can be accessed using enter teleporters where is_series==2.

At that point, the `box` meta value determines the category, not
the box id. Then the next box that is unplayed in that category
is offered for play.

For now, the player is sent a message if there are no more
unplayed boxes in a category.

mods/boxes/nodes.lua

@@ -183,7 +183,8 @@ register_teleport("boxes:enter_teleport", {
 	on_teleport = function(pos, node, player)
 		local meta = minetest.get_meta(pos)
 		local id = meta:get_int("box")
-		if meta:get_int("is_series") == 1 then
+		local is_series = meta:get_int("is_series")
+		if is_series == 1 then
 			local smeta = db.series_get_meta(id)
 			if not smeta then
 				return
@@ -199,6 +200,37 @@ register_teleport("boxes:enter_teleport", {
 			end
 
 			return
+		else if is_series == 2 then
+			if not ranks or not ranks.categories then
+				minetest.log("error", "ranks mod not found, can't use category teleport")
+				return true
+			end
+
+			-- get the list of boxes for category (id)
+			local catboxes = ranks.categories[tostring(id)]
+
+			-- first, find first unplayed box in dynamic series
+			local name = player:get_player_name()
+			local player_id = db.player_get_id(name)
+			local playerboxes = db.player_get_completed_boxes(player_id)
+			for _, catbox in pairs(catboxes) do
+				if not playerboxes[catbox] then
+					local bmeta = db.box_get_meta(catbox)
+					if bmeta.type ~= db.BOX_TYPE then
+						return true
+					end
+
+					boxes.open_box(player, {0, catbox, 1})
+					return
+				end
+			end
+
+			-- fallback to a random one ?
+			-- FIXME implement
+			minetest.chat_send_player(name, "You've completed every " ..
+				"box in this category! Come back later to see if " ..
+				"there are new boxes in it.")
+			return
 		end
 		local bmeta = db.box_get_meta(id)
 		if bmeta.type ~= db.BOX_TYPE then
@@ -212,15 +244,24 @@ register_teleport("boxes:enter_teleport", {
 		end
 		local meta = minetest.get_meta(pos)
 		if puncher:get_player_control().sneak then
-			local is_series = meta:get_int("is_series")
-			meta:set_int("is_series", 1 - is_series)
-			minetest.chat_send_player(puncher:get_player_name(), "Destination is" ..
-					((is_series == 0) and " " or " not ") .. "a series")
+			-- 0: a box portal
+			-- 1: a numbered series portal
+			-- 2: a category portal
+			local is_series = meta:get_int("is_series") + 1
+			if is_series > 2 then
+				is_series = 0
+			end
+			meta:set_int("is_series", is_series)
+			minetest.chat_send_player(puncher:get_player_name(), "Teleporter is a" ..
+					((is_series == 0) and " box " or
+					 (is_series == 1) and " numbered series " or
+					 " category ") .. "portal")
 			return
 		end
 		local id = meta:get_int("box")
 		local newid = id + 1
-		if not db.box_exists(newid) then
+		local is_series = meta:get_int("is_series")
+		if is_series == 1 and not db.box_exists(newid) then
 			newid = 0
 		end
 		meta:set_int("box", newid)
@@ -233,7 +274,8 @@ register_teleport("boxes:enter_teleport", {
 		local meta = minetest.get_meta(pos)
 		local id = meta:get_int("box")
 		local newid = id - 1
-		if not db.box_exists(newid) then
+		local is_series = meta:get_int("is_series")
+		if is_series == 1 and not db.box_exists(newid) then
 			newid = db.get_last_box_id()
 		end
 		meta:set_int("box", newid)

mods/db/init.lua

@@ -204,6 +204,19 @@ function db.player_points(player_id, box_id, type, values, limit)
 	return true
 end
 
+function db.player_get_completed_boxes(player_id)
+	local stmt = itb_db:prepare[[
+	        SELECT DISTINCT box_id FROM points WHERE type='time' AND player_id = :player_id
+	]]
+	stmt:bind_names{player_id = player_id}
+	local boxes = {}
+	for row in stmt:nrows() do
+		boxes[row.box_id] = 1
+	end
+
+	return boxes
+end
+
 function db.player_get_points(filtertbl)
 	if not filtertbl then
 		filtertbl = {}