blockgame/mods/bg_crafting/api.lua

blockgame.crafting = blockgame.crafting or {}
local api = blockgame.crafting

local recipes = {}
api.registered_recipes = recipes

function api.register_stack_recipe (top_node, bottom_node, result, consumes_top)
	local consumes_top = consumes_top
	if consumes_top == nil then consumes_top = true end

	recipes[top_node] = recipes[top_node] or {}

	table.insert(recipes[top_node], {
		["type"] = "stack_two_nodes",
		index_key = top_node,
		top_node = top_node,
		bottom_node = bottom_node,
		result = result,
		consumes_top = consumes_top,
	})
end

function api.handle_placement (pos, new_node, placer, old_node, itemstack, pointed_thing)
	if recipes[new_node.name] == nil then return false end

	for _, recipe in pairs(recipes[new_node.name]) do
		local result = api.handle_stack_recipe(recipe, pos, new_node)
		if result then return not recipe.consumes_top end
	end

	return false
end

function api.handle_stack_recipe (recipe, pos, top_node)
	if top_node.name ~= recipe.top_node then return false end

	local down = vector.add(pos, vector.new(0, -1, 0))
	local below = minetest.get_node(down)
	if below.name ~= recipe.bottom_node then return false end

	minetest.remove_node(pos)
	minetest.set_node(down, recipe.result)

	return true
end

-- pummeling is heavily based on nodecore by Warr1024 (both the mechanic itself and the code here implementing it).

local pummel_recipes = {}

function api.register_pummel_recipe (def)
	local def = def or {}

	def.label = def.label or "unnamed pummel recipe"

	-- TODO: throw errors when these defs are invalid instead of just returning.
	if not def.used_item then return false end
	if not def.target_node then return false end
	if not type(def.on_success) == "function" then return false end

	local key = def.used_item
	def.index_key = key

	pummel_recipes[key] = pummel_recipes[key] or {}
	table.insert(pummel_recipes[key], def)
end

-- TODO: add support for pummel recipes using groups instead of just specific node names.
function api.pummel_check (pos, used_item, target_node)
	local key = used_item
	if not pummel_recipes[key] then return false end

	local potential_recipes = pummel_recipes[key]
	for _, def in pairs(potential_recipes) do
		if def.target_node == target_node.name then
			if type(def.check) == "function" and not def.check(pos, used_item, target_node) then
				return false
			end
			def.on_success(pos, used_item, target_node)
			return true
		end
	end
end


local pummeling = {}

-- NOTE: might wanna change this to somehow store pummels per-node instead of per-player?
blockgame.register_on_dignode(function (_, _, digger)
	if not (digger and digger:is_player()) then return end
	pummeling[digger:get_player_name()] = nil
end)

blockgame.register_on_punchnode(function (pos, node, puncher, pointed)
	if (not puncher:is_player()) or puncher:get_player_control().sneak then return end
	local player_name = puncher:get_player_name()
	-- if not minetest.interact(player_name) then return end
	if not minetest.check_player_privs(player_name, "interact") then return end

	node = node or minetest.get_node(pos)
	local node_def = minetest.registered_items[node.name] or {}
	if not node_def.pointable then return end

	local wield = puncher:get_wielded_item()
	local now = minetest.get_us_time() / 1000000

	local pummel_data = {
		action = "pummel",
		crafter = puncher,
		crafter_name = player_name,
		pos = pos,
		pointed = pointed,
		node = node,
		node_def = node_def,
		start = now,
		wield = wield:get_name() .. " " .. wield:get_count(),
		count = 0,
	}

	local old_data = pummeling[player_name]
	local hash = minetest.hash_node_position
	if old_data and hash(old_data.pos) == hash(pummel_data.pos)
		and hash(old_data.pointed.above) == hash(pummel_data.pointed.above)
		and hash(old_data.pointed.under) == hash(pummel_data.pointed.under)
		and old_data.wield == pummel_data.wield
		and old_data.last >= (now - 3)
		then pummel_data = old_data
	end

	pummel_data.count = pummel_data.count + 1
	pummel_data.last = now
	pummel_data.duration = now - pummel_data.start - 1
	pummeling[player_name] = pummel_data

	if pummel_data.count < 2 then return end

	if api.pummel_check(pos, wield:get_name(), minetest.get_node(pointed.under)) then
		pummeling[player_name] = nil
	end
end)