Add u_i initialization and craft registration callbacks (#184)

Main purpose: custom recipe sorting provided by cuszom mods.

api.lua

@@ -152,6 +152,10 @@ minetest.after(0.01, function()
 			end
 		end
 	end
+
+	for _, callback in ipairs(ui.initialized_callbacks) do
+		callback()
+	end
 end)
 
 
@@ -212,10 +216,15 @@ function ui.register_craft(options)
 	if options.type == "normal" and options.width == 0 then
 		options = { type = "shapeless", items = options.items, output = options.output, width = 0 }
 	end
-	if not ui.crafts_for.recipe[itemstack:get_name()] then
+	local item_name = itemstack:get_name()
-		ui.crafts_for.recipe[itemstack:get_name()] = {}
+	if not ui.crafts_for.recipe[item_name] then
+		ui.crafts_for.recipe[item_name] = {}
+	end
+	table.insert(ui.crafts_for.recipe[item_name],options)
+
+	for _, callback in ipairs(ui.craft_registered_callbacks) do
+		callback(item_name, options)
 	end
-	table.insert(ui.crafts_for.recipe[itemstack:get_name()],options)
 end
 
 
@@ -309,6 +318,32 @@ function ui.register_button(name, def)
 	table.insert(ui.buttons, def)
 end
 
+function ui.register_on_initialized(callback)
+	if type(callback) ~= "function" then
+		error(("Initialized callback must be a function, %s given."):format(type(callback)))
+	end
+	table.insert(ui.initialized_callbacks, callback)
+end
+
+function ui.register_on_craft_registered(callback)
+	if type(callback) ~= "function" then
+		error(("Craft registered callback must be a function, %s given."):format(type(callback)))
+	end
+	table.insert(ui.craft_registered_callbacks, callback)
+end
+
+function ui.get_recipe_list(output)
+	return ui.crafts_for.recipe[output]
+end
+
+function ui.get_registered_outputs()
+	local outputs = {}
+	for item_name, _ in pairs(ui.crafts_for.recipe) do
+		table.insert(outputs, item_name)
+	end
+	return outputs
+end
+
 function ui.is_creative(playername)
 	return minetest.check_player_privs(playername, {creative=true})
 		or minetest.settings:get_bool("creative_mode")

doc/mod_api.txt

@@ -20,6 +20,64 @@ Grouped by use-case, afterwards sorted alphabetically.
 	* Checks whether creative is enabled or the player has `creative`
 
 
+Callbacks
+---------
+
+Register a callback that will be run whenever a craft is registered via unified_inventory.register_craft:
+
+	unified_inventory.register_on_craft_registered(
+		function (item_name, options)
+			-- item_name (string): name of the output item, equivalent to `ItemStack:get_name()`
+			-- options (table): definition table of crafts registered by `unified_inventory.register_craft`
+		end
+	)
+
+Register a callback that will be run after all mods have loaded and after the unified_inventory mod has initialised all its internal structures:
+
+	unified_inventory.register_on_initialized(callback)
+		-- The callback is passed no arguments
+
+
+Accessing Data
+--------------
+
+These methods should be used instead of accessing the unified_inventory data structures directly - this will ensure your code survives any potential restructuring of the mod.
+
+Get a list of recipes for a particular output item:
+
+	unified_inventory.get_recipe_list(output_item)
+
+	Returns a list of tables, each holding a recipe definition, like:
+	{
+		{
+			type = "normal",
+			items = { "default:stick", "default:stick", "default:stick", "default:stick" },
+			output = "default:wood",
+			width = 2
+		},
+		{
+			type = "shapeless",
+			items = { "default:tree" },
+			output = "default:wood 4",
+			width = 0
+		},
+		...
+	}
+
+Get a list of all the output items crafts have been registered for:
+
+	unified_inventory.get_registered_outputs()
+
+	Returns a list of item names, like:
+	{
+		"default:stone",
+		"default:chest",
+		"default:brick",
+		"doors:door_wood",
+		...
+	}
+
+
 Pages
 -----
 

init.lua

@@ -24,6 +24,8 @@ unified_inventory = {
 	filtered_items_list = {},
 	pages = {},
 	buttons = {},
+	initialized_callbacks = {},
+	craft_registered_callbacks = {},
 
 	-- Homepos stuff
 	home_pos = {},