From 61ae85a09cf818e3cc9a95cbcb7ab9932dc990c4 Mon Sep 17 00:00:00 2001
From: Jean-Patrick Guerrero <jeanpatrick.guerrero@gmail.com>
Date: Fri, 18 Jan 2019 17:15:25 +0100
Subject: [PATCH] Progressive mode: Add functions in API to add/set/get filters

---
 README.md | 26 ++++++++++++++++----------
 init.lua  | 40 ++++++++++++++++++++++++++++++++--------
 2 files changed, 48 insertions(+), 18 deletions(-)

diff --git a/README.md b/README.md
index 6be78cc..f9a2972 100644
--- a/README.md
+++ b/README.md
@@ -44,25 +44,31 @@ craftguide.register_craft({
 
 ### Progressive mode
 
-#### `craftguide.progressive_filter_recipes(recipes, player)`
+#### `craftguide.add_progressive_filter(function(recipes, player))`
 
-This function is used to filter recipes when progressive mode is enabled. It can
-be overridden to change the recipes that are normally displayed.
-
-The function should return the recipes to be displayed, given the available
-recipes and an `ObjectRef` to the craft guide user. Each recipe is a table of
-the form returned by `minetest.get_craft_recipe`.
+This function adds a recipe filter when progressive mode is enabled.
+The default `craftguide` filter will still be used.
 
 Example function to hide recipes for items from a mod called "secretstuff":
 
 ```lua
-function craftguide.progressive_filter_recipes(recipes, player)
+craftguide.add_progressive_filter(function(recipes)
 	local filtered = {}
 	for _, recipe in ipairs(recipes) do
-		if recipe.output:sub(1, 12) ~= "secretstuff:" then
+		if recipe.output:sub(1,12) ~= "secretstuff:" then
 			filtered[#filtered + 1] = recipe
 		end
 	end
+
 	return filtered
-end
+end)
 ```
+
+#### `craftguide.set_progressive_filter(function(recipes, player))`
+
+This function sets an unique recipes filter when progressive mode is enabled.
+The default `craftguide` progressive filter will be overridden.
+
+#### `craftguide.get_progressive_filters()`
+
+This function returns all progressive filters that are applied to recipes in progressive mode.
diff --git a/init.lua b/init.lua
index 48241d4..7ec8a44 100644
--- a/init.lua
+++ b/init.lua
@@ -553,7 +553,7 @@ local function progressive_show_recipe(recipe, inv_items)
 	return true
 end
 
-function craftguide.progressive_filter_recipes(recipes, player)
+local function progressive_default_filter(recipes, player)
 	local inv_items = get_inv_items(player)
 	if #inv_items == 0 then
 		return {}
@@ -570,12 +570,35 @@ function craftguide.progressive_filter_recipes(recipes, player)
 	return filtered
 end
 
+local progressive_filters = {progressive_default_filter}
+
+function craftguide.add_progressive_filter(func)
+	progressive_filters[#progressive_filters + 1] = func
+end
+
+function craftguide.set_progressive_filter(func)
+	progressive_filters = {func}
+end
+
+function craftguide.get_progressive_filters()
+	return progressive_filters
+end
+
+local function apply_progressive_filters(recipes, player)
+	for i = 1, #progressive_filters do
+		local func = progressive_filters[i]
+		recipes = func(recipes, player)
+	end
+
+	return recipes
+end
+
 local function get_progressive_items(player)
 	local items = {}
 	for i = 1, #init_items do
 		local item = init_items[i]
 		local recipes = get_recipes(item)
-		recipes = craftguide.progressive_filter_recipes(recipes, player)
+		recipes = apply_progressive_filters(recipes, player)
 
 		if #recipes > 0 then
 			items[#items + 1] = item
@@ -695,7 +718,7 @@ local function get_fields(player, ...)
 			local recipes = get_recipes(item)
 
 			if progressive_mode then
-				recipes = craftguide.progressive_filter_recipes(recipes, player)
+				recipes = apply_progressive_filters(recipes, player)
 			end
 
 			local no_recipes = not next(recipes)
@@ -725,8 +748,9 @@ local function get_fields(player, ...)
 					}
 				end
 
-				if progressive_mode then
-					data.usages = craftguide.progressive_filter_recipes(data.usages, player)
+				if progressive_mode and next(data.usages) then
+					data.usages =
+						apply_progressive_filters(data.usages, player)
 				end
 
 				if not next(data.usages) then
@@ -933,7 +957,7 @@ end
 
 --[[ Custom recipes (>3x3) test code
 
-mt.register_craftitem("craftguide:custom_recipe_test", {
+mt.register_craftitem(":secretstuff:custom_recipe_test", {
 	description = "Custom Recipe Test",
 })
 
@@ -943,12 +967,12 @@ for x = 1, 6 do
 	for i = 1, 10 - x do
 		cr[x][i] = {}
 		for j = 1, 10 - x do
-			cr[x][i][j] = "group:wood"
+			cr[x][i][j] = "group:sand"
 		end
 	end
 
 	mt.register_craft({
-		output = "craftguide:custom_recipe_test",
+		output = "secretstuff:custom_recipe_test",
 		recipe = cr[x]
 	})
 end