[Freeciv-Dev] (PR#2930) building requirements for units v2

["Per I. Mathisen via RT" <rt@xxxxxxxxxxxxxx>]

This patch adds a new field to units.ruleset called "impr_req", which
makes the building of a unit conditional upon the presence of the given
building.

I have committed the AI and bugfix parts of the patch separately. It is
now very small and should be easy to review & commit.

  - Per

Index: ai/advmilitary.c
===================================================================
RCS file: /home/freeciv/CVS/freeciv/ai/advmilitary.c,v
retrieving revision 1.134
diff -u -r1.134 advmilitary.c
--- ai/advmilitary.c    30 Jan 2003 19:53:50 -0000      1.134
+++ ai/advmilitary.c    30 Jan 2003 20:14:20 -0000
@@ -954,7 +954,17 @@
             best_choice->choice = unit_type;
             best_choice->want = want;
             best_choice->type = CT_ATTACKER;
-          } /* FIXME: else find out why we can't build it and do something */
+          } else if (can_build_improvement(pcity,
+                            get_unit_type(unit_type)->impr_requirement)) {
+            Impr_Type_id id = get_unit_type(unit_type)->impr_requirement;
+
+            CITY_LOG(LOG_DEBUG, pcity, "building %s to build %s",
+                     get_improvement_type(id)->name,
+                     get_unit_type(unit_type)->name);
+            best_choice->choice = id;
+            best_choice->want = want;
+            best_choice->type = CT_BUILDING;
+          }
         }
       }
     }
Index: client/packhand.c
===================================================================
RCS file: /home/freeciv/CVS/freeciv/client/packhand.c,v
retrieving revision 1.278
diff -u -r1.278 packhand.c
--- client/packhand.c   30 Jan 2003 19:26:07 -0000      1.278
+++ client/packhand.c   30 Jan 2003 20:14:21 -0000
@@ -1761,6 +1761,7 @@
   u->defense_strength   = p->defense_strength;
   u->move_rate          = p->move_rate;
   u->tech_requirement   = p->tech_requirement;
+  u->impr_requirement   = p->impr_requirement;
   u->vision_range       = p->vision_range;
   u->transport_capacity = p->transport_capacity;
   u->hp                 = p->hp;
Index: common/capstr.c
===================================================================
RCS file: /home/freeciv/CVS/freeciv/common/capstr.c,v
retrieving revision 1.118
diff -u -r1.118 capstr.c
--- common/capstr.c     30 Jan 2003 19:26:08 -0000      1.118
+++ common/capstr.c     30 Jan 2003 20:14:21 -0000
@@ -75,7 +75,7 @@
  */
 
 #define CAPABILITY "+1.14.0 conn_info +occupied team tech_impr_gfx " \
-                   "city_struct_minor_cleanup obsolete_last"
+                   "city_struct_minor_cleanup obsolete_last +impr_req"
   
 /* "+1.14.0" is protocol for 1.14.0 release.
  *
@@ -95,6 +95,8 @@
  *
  * "obsolete_last" means A_LAST is used to mark improvements that are never
  * obsoleted.  Previously A_NONE was used.
+ *
+ * "impr_req" is city improvements as a prerequisite for building units
  */
 
 void init_our_capability(void)
Index: common/city.c
===================================================================
RCS file: /home/freeciv/CVS/freeciv/common/city.c,v
retrieving revision 1.177
diff -u -r1.177 city.c
--- common/city.c       16 Jan 2003 18:23:35 -0000      1.177
+++ common/city.c       30 Jan 2003 20:14:21 -0000
@@ -398,15 +398,22 @@
   return(could_build_improvement(pcity, id));
 }
 
-
 /**************************************************************************
 Whether given city can build given unit,
 ignoring whether unit is obsolete.
 **************************************************************************/
 bool can_build_unit_direct(struct city *pcity, Unit_Type_id id)
 {
-  if (!can_player_build_unit_direct(city_owner(pcity), id))
+  Impr_Type_id impr_req;
+
+  if (!can_player_build_unit_direct(city_owner(pcity), id)) {
+    return FALSE;
+  }
+  impr_req = get_unit_type(id)->impr_requirement;
+  assert(impr_req <= B_LAST && impr_req >= 0);
+  if (impr_req != B_LAST && !city_got_building(pcity, impr_req)) {
     return FALSE;
+  }
   if (!is_ocean_near_tile(pcity->x, pcity->y) && is_water_unit(id)) {
     return FALSE;
   }
Index: common/packets.c
===================================================================
RCS file: /home/freeciv/CVS/freeciv/common/packets.c,v
retrieving revision 1.230
diff -u -r1.230 packets.c
--- common/packets.c    30 Jan 2003 19:26:08 -0000      1.230
+++ common/packets.c    30 Jan 2003 20:14:22 -0000
@@ -1937,6 +1937,7 @@
   dio_put_uint8(&dout, packet->defense_strength);
   dio_put_uint8(&dout, packet->move_rate);
   dio_put_uint8(&dout, packet->tech_requirement);
+  dio_put_uint8(&dout, packet->impr_requirement);
   dio_put_uint8(&dout, packet->vision_range);
   dio_put_uint8(&dout, packet->transport_capacity);
   dio_put_uint8(&dout, packet->hp);
@@ -1988,6 +1989,7 @@
   dio_get_uint8(&din, &packet->defense_strength);
   dio_get_uint8(&din, &packet->move_rate);
   dio_get_uint8(&din, &packet->tech_requirement);
+  dio_get_uint8(&din, &packet->impr_requirement);
   dio_get_uint8(&din, &packet->vision_range);
   dio_get_uint8(&din, &packet->transport_capacity);
   dio_get_uint8(&din, &packet->hp);
Index: common/packets.h
===================================================================
RCS file: /home/freeciv/CVS/freeciv/common/packets.h,v
retrieving revision 1.131
diff -u -r1.131 packets.h
--- common/packets.h    16 Jan 2003 18:23:36 -0000      1.131
+++ common/packets.h    30 Jan 2003 20:14:22 -0000
@@ -606,6 +606,7 @@
   int defense_strength;
   int move_rate;
   int tech_requirement;
+  int impr_requirement;
   int vision_range;
   int transport_capacity;
   int hp;
Index: common/unittype.c
===================================================================
RCS file: /home/freeciv/CVS/freeciv/common/unittype.c,v
retrieving revision 1.25
diff -u -r1.25 unittype.c
--- common/unittype.c   14 Jan 2003 22:24:07 -0000      1.25
+++ common/unittype.c   30 Jan 2003 20:14:22 -0000
@@ -419,6 +419,9 @@
 **************************************************************************/
 bool can_player_build_unit_direct(struct player *p, Unit_Type_id id)
 {
+  Impr_Type_id impr_req;
+  Tech_Type_id tech_req;
+
   if (!unit_type_exists(id))
     return FALSE;
   if (unit_type_flag(id, F_NUCLEAR) && game.global_wonders[B_MANHATTEN] == 0)
@@ -428,6 +431,11 @@
     return FALSE;
   if (get_invention(p,unit_types[id].tech_requirement)!=TECH_KNOWN)
     return FALSE;
+  impr_req = unit_types[id].impr_requirement;
+  tech_req = get_improvement_type(impr_req)->tech_req;
+  if (impr_req != B_LAST && get_invention(p, tech_req) != TECH_KNOWN) {
+    return FALSE;
+  }
   return TRUE;
 }
 
Index: common/unittype.h
===================================================================
RCS file: /home/freeciv/CVS/freeciv/common/unittype.h,v
retrieving revision 1.18
diff -u -r1.18 unittype.h
--- common/unittype.h   14 Jan 2003 22:24:07 -0000      1.18
+++ common/unittype.h   30 Jan 2003 20:14:22 -0000
@@ -167,6 +167,7 @@
   int defense_strength;
   int move_rate;
   int tech_requirement;
+  int impr_requirement;
   int vision_range;
   int transport_capacity;
   int hp;
Index: data/default/units.ruleset
===================================================================
RCS file: /home/freeciv/CVS/freeciv/data/default/units.ruleset,v
retrieving revision 1.43
diff -u -r1.43 units.ruleset
--- data/default/units.ruleset  28 Jan 2003 01:50:14 -0000      1.43
+++ data/default/units.ruleset  30 Jan 2003 20:14:23 -0000
@@ -44,6 +44,7 @@
 ;                for no alternate graphic.
 ; tech_req      = required advance, names from techs.ruleset, or special:
 ;                 "None" => available from start; "Never" => never available
+; impr_req     = required city improvement, names from buildings.ruleset
 ; obsolete_by   = can be upgraded to and made obsolete by another unit by name
 ; move_type     = "Land" or "Sea" or "Air" or "Heli"
 ; transport_cap = Number of units (ground, or air/missiles, depending on flags)
Index: server/ruleset.c
===================================================================
RCS file: /home/freeciv/CVS/freeciv/server/ruleset.c,v
retrieving revision 1.132
diff -u -r1.132 ruleset.c
--- server/ruleset.c    30 Jan 2003 19:26:08 -0000      1.132
+++ server/ruleset.c    30 Jan 2003 20:14:23 -0000
@@ -651,7 +651,11 @@
   /* main stats: */
   unit_type_iterate(i) {
     u = &unit_types[i];
-    
+
+    u->impr_requirement = find_improvement_by_name(
+                           secfile_lookup_str_default(file, "None", 
+                           "%s.impr_req", sec[i]));
+
     sval = secfile_lookup_str(file, "%s.move_type", sec[i]);
     ival = unit_move_type_from_str(sval);
     if (ival==0) {
@@ -2418,6 +2422,7 @@
     packet.defense_strength = u->defense_strength;
     packet.move_rate = u->move_rate;
     packet.tech_requirement = u->tech_requirement;
+    packet.impr_requirement = u->impr_requirement;
     packet.vision_range = u->vision_range;
     packet.transport_capacity = u->transport_capacity;
     packet.hp = u->hp;