From 2d92a871aa92182bf20c55229da7cde0df8b573b Mon Sep 17 00:00:00 2001
From: mwerezak <mwerezak@gmail.com>
Date: Sat, 30 May 2015 17:17:45 -0400
Subject: [PATCH] Optimizes reaction checks

---
 code/modules/reagents/Chemistry-Holder.dm  | 18 ++++++++++++++++++
 code/modules/reagents/Chemistry-Recipes.dm | 17 ++++++-----------
 2 files changed, 24 insertions(+), 11 deletions(-)

diff --git a/code/modules/reagents/Chemistry-Holder.dm b/code/modules/reagents/Chemistry-Holder.dm
index 4ad6e7337c..775da2bbb3 100644
--- a/code/modules/reagents/Chemistry-Holder.dm
+++ b/code/modules/reagents/Chemistry-Holder.dm
@@ -183,6 +183,24 @@
 				return 0
 	return 0
 
+/datum/reagents/proc/has_any_reagent(var/list/check_reagents)
+	for(var/datum/reagent/current in reagent_list)
+		if(current.id in check_reagents)
+			if(current.volume >= check_reagents[current.id])
+				return 1
+			else
+				return 0
+	return 0
+
+/datum/reagents/proc/has_all_reagents(var/list/check_reagents)
+	//this only works if check_reagents has no duplicate entries... hopefully okay since it expects an associative list
+	var/missing = check_reagents.len
+	for(var/datum/reagent/current in reagent_list)
+		if(current.id in check_reagents)
+			if(current.volume >= check_reagents[current.id])
+				missing--
+	return !missing
+
 /datum/reagents/proc/clear_reagents()
 	for(var/datum/reagent/current in reagent_list)
 		del_reagent(current.id)
diff --git a/code/modules/reagents/Chemistry-Recipes.dm b/code/modules/reagents/Chemistry-Recipes.dm
index 8615b73452..5db9f290e7 100644
--- a/code/modules/reagents/Chemistry-Recipes.dm
+++ b/code/modules/reagents/Chemistry-Recipes.dm
@@ -54,21 +54,16 @@
 
 /datum/chemical_reaction/proc/can_happen(var/datum/reagents/holder)
 	//check that all the required reagents are present
-	for(var/reagent in required_reagents)
-		if(!holder.has_reagent(reagent))
-			return 0
+	if(!holder.has_all_reagents(required_reagents))
+		return 0
 
 	//check that all the required catalysts are present in the required amount
-	for(var/reagent in catalysts)
-		var/min_req_amt = catalysts[reagent]
-		if(!holder.has_reagent(reagent, min_req_amt))
-			return 0
+	if(!holder.has_all_reagents(catalysts))
+		return 0
 
 	//check that none of the inhibitors are present in the required amount
-	for(var/reagent in inhibitors)
-		var/min_req_amt = inhibitors[reagent]
-		if(holder.has_reagent(reagent, min_req_amt))
-			return 0
+	if(holder.has_any_reagent(inhibitors))
+		return 0
 
 	return 1