[Freeciv-Dev] (PR#8882) city_can_use_specialist

["Jason Short" <jdorje@xxxxxxxxxxxxxxxxxxxxx>]

<URL: http://rt.freeciv.org/Ticket/Display.html?id=8882 >

This patch adds the self-explanatory function city_can_use_specialist. 
It also changes or creates some users:

- cm.c already had an identical function.  This function is removed.

- cityhand.c is just a one-line change to use it.

- citydlg_common.c didn't use it, but should have.  For instance with 
the current code if you can support elvises and taxmen the citydlg does 
not let you switch between them.  Instead it keeps trying to switch from 
elvises to scientists which fails.  The replacement code loops over the 
specialists in order, skipping past ones that aren't available.  And it 
doesn't send a change packet to the server if there is no change 
possible (currently if you click on an elvis, the client sends a 
change-to-scientist packet to the server which the server discards - I 
think).

jason

? ferries
? data/flags
Index: client/citydlg_common.c
===================================================================
RCS file: /home/freeciv/CVS/freeciv/client/citydlg_common.c,v
retrieving revision 1.34
diff -u -r1.34 citydlg_common.c
--- client/citydlg_common.c     27 May 2004 22:14:18 -0000      1.34
+++ client/citydlg_common.c     31 May 2004 16:50:27 -0000
@@ -417,24 +417,18 @@
 
   get_city_citizen_types(pcity, 4, citizens);
 
-  switch (citizens[citizen_index]) {
-  case CITIZEN_ELVIS:
-    from = SP_ELVIS;
-    to = SP_SCIENTIST;
-    break;
-  case CITIZEN_SCIENTIST:
-    from = SP_SCIENTIST;
-    to = SP_TAXMAN;
-    break;
-  case CITIZEN_TAXMAN:
-    from = SP_TAXMAN;
-    to = SP_ELVIS;
-    break;
-  default:
-    return;
-  }
+  to = from = citizens[citizen_index];
+  assert(to >= 0 && to < SP_COUNT);
+
+  /* Loop through all specialists in order until we find a usable one
+   * (or run out of choices). */
+  do {
+    to = (to + 1) % SP_COUNT;
+  } while (to != from && !city_can_use_specialist(pcity, to));
 
-  city_change_specialist(pcity, from, to);
+  if (from != to) {
+    city_change_specialist(pcity, from, to);
+  }
 }
     
 /**************************************************************************
Index: common/city.c
===================================================================
RCS file: /home/freeciv/CVS/freeciv/common/city.c,v
retrieving revision 1.214
diff -u -r1.214 city.c
--- common/city.c       31 May 2004 16:38:54 -0000      1.214
+++ common/city.c       31 May 2004 16:50:28 -0000
@@ -461,6 +461,14 @@
   return TRUE;
 }
 
+/****************************************************************************
+  Returns TRUE iff if the given city can use this kind of specialist.
+****************************************************************************/
+bool city_can_use_specialist(struct city *pcity,
+                            enum specialist_type type)
+{
+  return pcity->size >= game.rgame.specialists[type].min_size;
+}
 
 /**************************************************************************
  Returns how many thousand citizen live in this city.
Index: common/city.h
===================================================================
RCS file: /home/freeciv/CVS/freeciv/common/city.h,v
retrieving revision 1.144
diff -u -r1.144 city.h
--- common/city.h       27 May 2004 22:14:18 -0000      1.144
+++ common/city.h       31 May 2004 16:50:28 -0000
@@ -362,6 +362,7 @@
 bool can_build_unit(struct city *pcity, Unit_Type_id id);
 bool can_build_unit_direct(struct city *pcity, Unit_Type_id id);
 bool can_eventually_build_unit(struct city *pcity, Unit_Type_id id);
+bool city_can_use_specialist(struct city *pcity, enum specialist_type type);
 bool city_got_building(struct city *pcity,  Impr_Type_id id); 
 bool city_affected_by_wonder(struct city *pcity, Impr_Type_id id);
 bool city_got_effect(struct city *pcity, Impr_Type_id id);
Index: common/aicore/cm.c
===================================================================
RCS file: /home/freeciv/CVS/freeciv/common/aicore/cm.c,v
retrieving revision 1.22
diff -u -r1.22 cm.c
--- common/aicore/cm.c  29 May 2004 20:34:31 -0000      1.22
+++ common/aicore/cm.c  31 May 2004 16:50:30 -0000
@@ -302,21 +302,6 @@
 }
 
 /****************************************************************************
- Returns TRUE iff if the given city can use this kind of specialists.
-*****************************************************************************/
-static bool can_use_specialist(struct city *pcity,
-                              enum specialist_type specialist_type)
-{
-  if (specialist_type == SP_ELVIS) {
-    return TRUE;
-  }
-  if (pcity->size >= 5) {
-    return TRUE;
-  }
-  return FALSE;
-}
-
-/****************************************************************************
  Returns TRUE iff is the result has the required surplus and the city
  isn't in disorder and the city is happy if this is required.
 *****************************************************************************/
@@ -1258,13 +1243,13 @@
 
     int i, items;
 
-    if (can_use_specialist(pcity, SP_SCIENTIST)) {
+    if (city_can_use_specialist(pcity, SP_SCIENTIST)) {
       base_combination->max_scientists = specialists;
     } else {
       base_combination->max_scientists = 0;
     }
 
-    if (can_use_specialist(pcity, SP_TAXMAN)) {
+    if (city_can_use_specialist(pcity, SP_TAXMAN)) {
       base_combination->max_taxmen = specialists;
     } else {
       base_combination->max_taxmen = 0;
Index: server/cityhand.c
===================================================================
RCS file: /home/freeciv/CVS/freeciv/server/cityhand.c,v
retrieving revision 1.131
diff -u -r1.131 cityhand.c
--- server/cityhand.c   31 May 2004 16:38:55 -0000      1.131
+++ server/cityhand.c   31 May 2004 16:50:31 -0000
@@ -74,7 +74,7 @@
 
   if (to < 0 || to >= SP_COUNT
       || from < 0 || from >= SP_COUNT
-      || pcity->size < game.rgame.specialists[to].min_size
+      || !city_can_use_specialist(pcity, to)
       || pcity->specialists[from] == 0) {
     freelog(LOG_ERROR, "Error in specialist change request from client.");
     return;