1 files changed, 32 insertions, 0 deletions
diff --git a/Calculator.lua b/Calculator.lua
new file mode 100644
index 0000000..aece972
--- /dev/null
+++ b/Calculator.lua
@@ -0,0 +1,32 @@
+local Recipe = require "Recipe"
+
+
+local
+function raw_materials_needed (quantity)
+	local recipe = Recipe[quantity.material]
+	if not recipe then
+		return {[quantity.material]=quantity.amount}
+	end
+	local total = {}
+	for _, input in pairs(recipe.input) do
+		local subtotal = raw_materials_needed(input)
+		for material, amount in pairs(subtotal) do
+			total[material] = (total[material] or 0) + amount * quantity.amount
+		end
+	end
+	return total
+end
+
+
+local
+function pretty_print (acc)
+	for material, amount in pairs(acc) do
+		print(("%d\t%q"):format(amount, material))
+	end
+end
+
+
+return {
+	raw_materials_needed=raw_materials_needed,
+	pretty_print=pretty_print,
+}