Add simple item fluid storage API

api.lua

@@ -151,6 +151,79 @@ industrialtest.api.afterToolUse=function(itemstack)
 	meta:set_int("industrialtest.uses",uses)
 	itemstack:set_wear(65535-uses/def.tool_capabilities.uses*65535)
 end
+
+-- \brief Check if itemstack contains fluid storage
+-- \param itemstack ItemStack
+-- \returns bool
+industrialtest.api.itemHasFluidStorage=function(itemstack)
+	local values={"industrialtest.fluidAmount","industrialtest.fluidCapacity"}
+	local meta=itemstack:get_meta()
+	for _,value in ipairs(values) do
+		if not meta:contains(value) then
+			return false
+		end
+	end
+	return true
+end
+
+-- \brief Updates itemstack description and wear depending on contained fluid
+-- \param itemstack ItemStack
+-- \returns nil
+industrialtest.api.updateItemFluidText=function(itemstack)
+	local meta=itemstack:get_meta()
+	local def=itemstack:get_definition()
+	meta:set_string("description",S("@1\n@2 / @3",def.description,meta:get_int("industrialtest.fluidAmount"),meta:get_int("industrialtest.fluidCapacity")))
+	itemstack:set_wear(65535-meta:get_int("industrialtest.fluidAmount")/meta:get_int("industrialtest.fluidCapacity")*65534)
+end
+
+-- \brief Prepares itemstack containing fluid storage
+-- \param itemstack ItemStack
+-- \returns bool
+industrialtest.api.prepareFluidStorageItem=function(itemstack)
+	local meta=itemstack:get_meta()
+	local def=itemstack:get_definition()
+	if industrialtest.api.itemHasFluidStorage(itemstack) or not def.groups or not def.groups._industrialtest_fluidStorage or not def._industrialtest_fluidCapacity then
+		return false
+	end
+	meta:set_int("industrialtest.fluidAmount",100)
+	meta:set_int("industrialtest.fluidCapacity",def._industrialtest_fluidCapacity)
+	industrialtest.api.updateItemFluidText(itemstack)
+	return true
+end
+
+-- \brief Adds fluid amount to item fluid storage
+-- \param itemstack ItemStack
+-- \param amount number
+-- \returns number
+industrialtest.api.addFluidToItem=function(itemstack,amount)
+	local meta=itemstack:get_meta()
+	if not industrialtest.api.itemHasFluidStorage(itemstack) then
+		return 0
+	end
+	local fluidAmount=meta:get_int("industrialtest.fluidAmount")
+	local fluidCapacity=meta:get_int("industrialtest.fluidCapacity")
+	local prevFluidAmount=fluidAmount
+	fluidAmount=industrialtest.internal.clamp(fluidAmount+amount,0,fluidCapacity)
+	meta:set_int("industrialtest.fluidAmount",fluidAmount)
+	industrialtest.api.updateItemFluidText(itemstack)
+	return fluidAmount-prevFluidAmount
+end
+
+-- \brief Adds fluid to destination itemstack while subtracting it from source metadata
+-- \param srcMeta MetaDataRef
+-- \param itemstack ItemStack
+-- \param amount number
+-- \returns number
+industrialtest.api.transferFluidToItem=function(srcMeta,itemstack,amount)
+	local flow=math.min(srcMeta:get_int("industrialtest.fluidAmount"),amount)
+	if flow==0 then
+		return 0
+	end
+	local actualFlow=industrialtest.api.addFluidToItem(itemstack,flow)
+	srcMeta:set_int("industrialtest.fluidAmount",srcMeta:get_int("industrialtest.fluidAmount")-actualFlow)
+	return actualFlow
+end
+
 -- \brief Checks if power storage is fully charged
 -- \param meta MetaDataRef which should be checked
 -- \returns true if power storage is fully charged, false otherwise
@@ -198,6 +271,7 @@ end
 -- \brief Adds power to destination itemstack while subtracting it from source metadata
 -- \param srcMeta MetaDataRef from which take power
 -- \param itemstack ItemStack to which add power
+-- \param amount number
 -- \returns How much of power was actually transferred
 industrialtest.api.transferPowerToItem=function(srcMeta,itemstack,amount)
 	local currentFlow=math.min(srcMeta:get_int("industrialtest.powerAmount"),amount)

craftitems.lua

@@ -690,8 +690,9 @@ minetest.register_tool("industrialtest:fuel_can",{
 	inventory_image="industrialtest_fuel_can.png",
 	groups={
 		_industrialtest_fueled=1,
-		_industrialtest_emptyOnConstruct=1
-	}
+		_industrialtest_fluidStorage=1
+	},
+	_industrialtest_fluidCapacity=10000
 })
 minetest.register_craft({
 	type="shaped",
@@ -706,14 +707,14 @@ minetest.register_craft({
 -- Item callbacks
 minetest.register_on_player_inventory_action(function(player,action,inventory,info)
 	if action=="put" then
-		if industrialtest.api.preparePowerStorageItem(info.stack) or industrialtest.api.prepareToolItem(info.stack) then
+		if industrialtest.api.preparePowerStorageItem(info.stack) or industrialtest.api.prepareToolItem(info.stack) or industrialtest.api.prepareFluidStorageItem(info.stack) then
 			inventory:set_stack(info.listname,info.index,info.stack)
 		end
 	end
 end)
 minetest.register_on_craft(function(itemstack)
-	if industrialtest.api.preparePowerStorageItem(itemstack) then
+	if industrialtest.api.preparePowerStorageItem(itemstack) or industrialtest.api.prepareToolItem(itemstack) then
 		return
 	end
-	industrialtest.api.prepareToolItem(itemstack)
+	industrialtest.api.prepareFluidStorageItem(itemstack)
 end)

tools/jetpack.lua

@@ -96,10 +96,11 @@ local function onGlobalStep(player,inv,itemstack,index,def)
 end
 
 jetpack.tryFly=function(itemstack)
-	if itemstack:get_wear()>=65533 then
+	local meta=itemstack:get_meta()
+	if meta:get_int("industrialtest.fluidAmount")==0 then
 		return false
 	end
-	itemstack:set_wear(itemstack:get_wear()+2)
+	industrialtest.api.addFluidToItem(itemstack,-1)
 	return true
 end
 
@@ -109,9 +110,12 @@ registerJetpack({
 	displayName=S("Jetpack"),
 	groups={
 		_industrialtest_fueled=1,
-		_industrialtest_emptyOnConstruct=1
+		_industrialtest_fluidStorage=1
 	},
-	tryFly=jetpack.tryFly
+	tryFly=jetpack.tryFly,
+	customKeys={
+		_industrialtest_fluidCapacity=5000
+	}
 })
 minetest.register_craft({
 	type="shaped",