Burnergenerator fixes

-fixed energy overflow
-fixed invalid items beeing allowed
-fixed restarting the burnergenrator on recieving new item

sparkgenerators/burnergenerator.lua

@@ -1,4 +1,6 @@
 local fuel_multiplier = 2
+local interval = 0.5
+
 
 local NAME = minetest.get_current_modname()
 
@@ -10,6 +12,25 @@ local formspec =
   "bgcolor[#FC05E344;false]" ..
   "listcolors[#fc059db0;#fc059dd0]"
 
+local function is_fuel(items)
+	local fuel
+	local afterfuel
+	fuel, afterfuel = minetest.get_craft_result({method = "fuel", width = 1, items = items})
+	return fuel["time"] ~= 0
+end
+
+local function is_item_allowed(pos, target, _, stack)
+	if stack == nil or not is_fuel({stack}) then
+		return 0
+	else
+		return stack:get_count()
+	end
+end
+
+local function ongetitem(pos) -- could add checking if energy >= max energy here, not really required since timer does that first thing anyway
+	local timer = minetest.get_node_timer(pos):start(interval)
+end
+
 local function update_formspec(pos)
 	local meta = minetest.get_meta(pos)
 	local inventory = meta:get_inventory()
@@ -22,12 +43,11 @@ local function update_formspec(pos)
 	local rem_en_or = meta:get_int("rem_energy_or_")
 
 	cfmsp = cfmsp ..
-	  sparktech.makebar("progress2.png", 1, 0, 8.5, 0.5,
+		sparktech.makebar("progress2.png", 1, 0, 8.5, 0.5, rem_en, rem_en_or, 0)
-			    rem_en, rem_en_or, 0)
 
 	cfmsp = cfmsp ..
-	  sparktech.makebar("energy2.png", 1, 0.5, 8.5, 0.5,
+		sparktech.makebar("energy2.png", 1, 0.5, 8.5, 0.5, energy, energy_max, 0)
-			    energy, energy_max, 0)
+
 	meta:set_string("formspec", cfmsp)
 end
 
@@ -42,10 +62,15 @@ minetest.register_node(NAME .. ":burnergenerator", {
 		"generator.png"},
 	paramtype2 = "facedir",
 	groups = {
+		--sparktech_energy_wakeup = 2,
+			-- sparktech_energy_wakeup
+			-- mode 1: wake on giving energy (only triggers if previous = 0)
+			-- mode 2: wake on taking energy (only triggers if previous = max)
+		-- TODO: Implement sparktech_energy_wakeup, furnace could also use this
 		sparktech_techy = 1,
 		sparktech_energy_type = 2,
 		sparktech_net_trigger = 1,
-    sparktech_energy_max = 5000
+		sparktech_energy_max = 2000
 	},
 	on_construct = function(pos)
 		local meta = minetest.get_meta(pos)
@@ -53,12 +78,26 @@ minetest.register_node(NAME .. ":burnergenerator", {
 		meta:set_int("rem_energy_", 0)
 		local inv = meta:get_inventory()
 		inv:set_size('fuel', 1)
-    minetest.get_node_timer(pos):start(0.5)
+	--	minetest.get_node_timer(pos):start(interval)
+	--	not required! its not like we got items on construct
 	end,
+	
+	allow_metadata_inventory_put = is_item_allowed,
+	
+	on_metadata_inventory_put = ongetitem,
+	
 	on_timer = function(pos, elapsed) -- Reduce number of ticks like in the furnace
 		local meta = minetest.get_meta(pos)
+		local max_energy = minetest.get_item_group(minetest.get_node(pos).name, "sparktech_energy_max")
+		local energy = meta:get_int("energy")
+		if (energy >= max_energy) then
+			return 	-- at this point no new cycle is requested, and as such the thing halts,
+				-- NOTE: would be really usefull to get the energy system to call the
+				-- ontimer function upon taking energy out here!!
+		end
 
 		local rem_energy = meta:get_int("rem_energy_")	
+
 		if rem_energy > 0 then
 			local change
 			if rem_energy > 5 then
@@ -67,7 +106,11 @@ minetest.register_node(NAME .. ":burnergenerator", {
 				change = rem_energy
 			end
 			meta:set_int("rem_energy_", meta:get_int("rem_energy_") - change)
-      meta:set_int("energy", meta:get_int("energy") + change)
+			if (energy + change >= max_energy) then
+				meta:set_int("energy", max_energy)
+			else
+				meta:set_int("energy", energy + change)
+			end
 		else
 			local inv = meta:get_inventory()
 			local itemlist = inv:get_list("fuel")
@@ -84,7 +127,7 @@ minetest.register_node(NAME .. ":burnergenerator", {
 
 		update_formspec(pos) -- Later this should only be done when a player looks into the block
 
-    minetest.get_node_timer(pos):start(0.5)
+		minetest.get_node_timer(pos):start(interval)
 	end
 })