From ba2600e7db0beec65baf12da4d6790b3096664e7 Mon Sep 17 00:00:00 2001
From: Markus Armbruster <armbru@pond.sub.org>
Date: Sun, 5 May 2013 17:09:00 +0200
Subject: [PATCH] Factor prod_resource_limit() out of produce() and prod()

---
 include/prototypes.h     |  1 +
 src/lib/commands/prod.c  |  8 ++++----
 src/lib/update/produce.c | 23 ++++++++++++++++++-----
 3 files changed, 23 insertions(+), 9 deletions(-)

diff --git a/include/prototypes.h b/include/prototypes.h
index 63d0a8d9..db4ab682 100644
--- a/include/prototypes.h
+++ b/include/prototypes.h
@@ -717,6 +717,7 @@ extern int bank_income(struct sctstr *, int);
 extern int produce(struct natstr *, struct sctstr *, short *, int, int,
 		   int, int *, int *);
 extern int prod_materials_cost(struct pchrstr *, short[], int *);
+extern int prod_resource_limit(struct pchrstr *, unsigned char *);
 extern double prod_eff(int, float);
 /* removewants.c */
 extern int update_removewants(void);
diff --git a/src/lib/commands/prod.c b/src/lib/commands/prod.c
index 504b7fe2..9f7cc8b8 100644
--- a/src/lib/commands/prod.c
+++ b/src/lib/commands/prod.c
@@ -82,6 +82,7 @@ prod(void)
     int there;
     int unit_work;		/* sum of component amounts */
     int used;			/* production w/infinite workforce */
+    int res_limit;
     i_type it;
     i_type vtype;
     unsigned char *resource;
@@ -227,10 +228,9 @@ prod(void)
 	 * workforce?
 	 */
 	max = (int)(work * p_e / (double)unit_work + 0.5);
-	if (resource && pp->p_nrdep != 0) {
-	    if (*resource * 100 < pp->p_nrdep * max)
-		max = *resource * 100 / pp->p_nrdep;
-	}
+	res_limit = prod_resource_limit(pp, resource);
+	if (max > res_limit)
+	    max = res_limit;
 	act = MIN(used, max);
 
 	real = (double)act * prodeff;
diff --git a/src/lib/update/produce.c b/src/lib/update/produce.c
index e136d271..2085c36e 100644
--- a/src/lib/update/produce.c
+++ b/src/lib/update/produce.c
@@ -57,7 +57,7 @@ produce(struct natstr *np, struct sctstr *sp, short *vec, int work,
     int unit_work;
     i_type item;
     int worker_limit;
-    int material_limit;
+    int material_limit, res_limit;
     int material_consume;
     int val;
 
@@ -93,10 +93,9 @@ produce(struct natstr *np, struct sctstr *sp, short *vec, int work,
     worker_limit = roundavg(work * p_e / unit_work);
     if (material_consume > worker_limit)
 	material_consume = worker_limit;
-    if (resource && product->p_nrdep != 0) {
-	if (*resource * 100 < product->p_nrdep * material_consume)
-	    material_consume = *resource * 100 / product->p_nrdep;
-    }
+    res_limit = prod_resource_limit(product, resource);
+    if (material_consume > res_limit)
+	material_consume = res_limit;
     if (material_consume == 0)
 	return 0;
     prodeff = prod_eff(desig, np->nat_level[product->p_nlndx]);
@@ -217,6 +216,20 @@ materials_charge(struct pchrstr *pp, short *vec, int count)
     }
 }
 
+/*
+ * Return how much of product PP can be made from its resource.
+ * If PP depletes a resource, RESOURCE must point to its value.
+ */
+int
+prod_resource_limit(struct pchrstr *pp, unsigned char *resource)
+{
+    if (CANT_HAPPEN(pp->p_nrndx && !resource))
+	return 0;
+    if (resource && pp->p_nrdep != 0)
+	return *resource * 100 / pp->p_nrdep;
+    return ITEM_MAX;
+}
+
 /*
  * Return p.e. for sector type TYPE.
  * Zero means level is too low for production.