[Add] You can now use lua as conditions for missions.

dat/mission.xml

@@ -32,7 +32,7 @@
   <mission name = "Empire Shipping">
     <lua>es_cargo</lua>
     <avail>
-      <req>es_cargo</req>
+      <cond>var.peek("es_cargo") == true</cond>
       <chance>350</chance>
       <location>Computer</location>
       <alliance>Empire United</alliance>

dat/missions/emp_scout00.lua

@@ -3,7 +3,7 @@ if lang == "es" then
   -- Not translated atm.
 else -- Default english.
   misn_title    = "Collective Scout"
-  misn_reward   = ""
+  misn_reward   = "None"
   misn_desc     = {}
   misn_desc[1]  = "Find a scout near %s."
   misn_desc[2]  = "Travel back to %s in %s."

src/misn_lua.c

@@ -94,6 +94,12 @@ static const luaL_reg var_methods[] = {
   {0, 0}
 };
 
+// Only conditional.
+static const luaL_reg var_cond_methods[] = {
+  { "peek", var_peek },
+  {0, 0 }
+};
+
 // Space.
 static int space_getPlanet(lua_State* L);
 static int space_getSystem(lua_State* L);
@@ -200,6 +206,12 @@ int misn_loadLibs(lua_State* L) {
   return 0;
 }
 
+int misn_loadCondLibs(lua_State* L) {
+  luaL_register(L, "time", time_methods);
+  luaL_register(L, "var", var_cond_methods);
+  return 0;
+}
+
 // Run a mission function.
 //
 // -1 on error, 1 on misn.finish() call and 0 normally.

src/misn_lua.h

@@ -8,4 +8,5 @@ void var_cleanup(void);
 
 // Load the libraries for a lua state.
 int misn_loadLibs(lua_State* L);
+int misn_loadCondLibs(lua_State* L); // Safe read only stuff.
 

src/mission.c

@@ -38,9 +38,10 @@ extern int misn_run(Mission* misn, char* func);
 
 // Static.
 static unsigned int mission_genID(void);
-static int  mission_init(Mission* mission, MissionData* misn);
+static int  mission_init(Mission* mission, MissionData* misn, int load);
 static void mission_freeData(MissionData* mission);
 static int  mission_alreadyRunning(MissionData* misn);
+static int  mission_meetCond(MissionData* misn);
 static int  mission_meetReq(int mission, int faction, char* planet, char* system);
 static int  mission_matchFaction(MissionData* misn, int faction);
 static int  mission_location(char* loc);
@@ -80,15 +81,16 @@ MissionData* mission_get(int id) {
 }
 
 // Initialize a mission.
-static int mission_init(Mission* mission, MissionData* misn) {
+static int mission_init(Mission* mission, MissionData* misn, int load) {
   char* buf;
   uint32_t bufsize;
 
-  if(misn != NULL) {
-    // Don't set the data either.
+  if(load != 0)
+    mission->id = 0;
+  else
     mission->id = mission_genID();
+
   mission->data = misn;
-  }
 
   // Sane defaults.
   mission->title    = NULL;
@@ -108,9 +110,6 @@ static int mission_init(Mission* mission, MissionData* misn) {
   luaopen_string(mission->L); // string.format can be very useful.
   misn_loadLibs(mission->L);  // Load our custom libraries.
 
-  // Don't load it with data.
-  if(misn != NULL) {
-    // Load the file.
   buf = pack_readfile(DATA, misn->lua, &bufsize);
   if(luaL_dobuffer(mission->L, buf, bufsize, misn->lua) != 0) {
     ERR("Error loading mission file: %s", misn->lua);
@@ -118,10 +117,10 @@ static int mission_init(Mission* mission, MissionData* misn) {
     WARN("Most likely Lua file has improper syntax, please check");
     return -1;
   }
-  }
   free(buf);
 
   // Run create function.
+  if(load == 0) // Never run when loading.
     misn_run(mission, "create");
 
   return mission->id;
@@ -145,6 +144,60 @@ static int mission_alreadyRunning(MissionData* misn) {
   return 0;
 }
 
+// Is the lua condition for misn met?
+static lua_State* mission_cond_L = NULL;
+static int mission_meetCond(MissionData* misn) {
+  int ret;
+  char buf[256];
+
+  if(mission_cond_L == NULL) {
+    // Must create the conditional environment.
+    mission_cond_L = luaL_newstate();
+    misn_loadCondLibs(mission_cond_L);
+  }
+  
+  snprintf(buf, 256, "return %s", misn->avail.cond);
+  ret = luaL_loadstring(mission_cond_L, buf);
+
+  switch(ret) {
+    case LUA_ERRSYNTAX:
+      WARN("Missions '%s' Lua Conditional syntax error", misn->name);
+      return 0;
+    case LUA_ERRMEM:
+      WARN("Mission '%s' Lua Conditional ran out of memory", misn->name);
+      return 0;
+    default:
+      break;
+  }
+
+  ret = lua_pcall(mission_cond_L, 0, 1, 0);
+  
+  switch(ret) {
+    case LUA_ERRRUN:
+      WARN("Mission '%s' Lua Conditional had a runtime error: %s",
+          misn->name, lua_tostring(mission_cond_L, -1));
+      return 0;
+    case LUA_ERRMEM:
+      WARN("Mission '%s' Lua Conditional ran out of memory", misn->name);
+      return 0;
+    case LUA_ERRERR:
+      WARN("Mission '%s' Lua Conditional had an error while handling error function",
+          misn->name);
+      return 0;
+    default:
+      break;
+  }
+
+  if(lua_isboolean(mission_cond_L, -1)) {
+    if(lua_toboolean(mission_cond_L, -1))
+      return 1;
+    else
+      return 0;
+  }
+  WARN("Mission '%s' Conditional Lua didn't return a boolean", misn->name);
+  return 0;
+}
+
 // Does the mission meet the minimum requirements?
 static int mission_meetReq(int mission, int faction, char* planet, char* system) {
   MissionData* misn;
@@ -162,8 +215,8 @@ static int mission_meetReq(int mission, int faction, char* planet, char* system)
        mission_alreadyRunning(misn)))
     return 0;
 
-  if((misn->avail.req != NULL) && // Mission doesn't meet the requirement.
-      !var_checkflag(misn->avail.req))
+  if((misn->avail.cond != NULL) && // Mission doesn't meet the requirement.
+      !mission_meetCond(misn))
     return 0;
 
   return 1;
@@ -185,7 +238,7 @@ void missions_bar(int faction, char* planet, char* system) {
       chance = (double)(misn->avail.chance % 100)/100.;
 
       if(RNGF() < chance) {
-        mission_init(&mission, misn);
+        mission_init(&mission, misn, 0);
         mission_cleanup(&mission); // It better clean up for itself or we do it.
       }
     }
@@ -300,7 +353,7 @@ Mission* missions_computer(int* n, int faction, char* planet, char* system) {
         // Random chance of rep appearances.
         if(RNGF() < chance) {
           tmp = realloc(tmp, sizeof(Mission) * ++m);
-          mission_init(&tmp[m-1], misn);
+          mission_init(&tmp[m-1], misn, 0);
         }
     }
   }
@@ -373,8 +426,8 @@ static MissionData* mission_parse(const xmlNodePtr parent) {
           tmp->avail.factions[tmp->avail.nfactions-1] = 
               faction_get(xml_get(cur));
         }
-        else if(xml_isNode(cur, "req"))
-          tmp->avail.req = strdup(xml_get(cur));
+        else if(xml_isNode(cur, "cond"))
+          tmp->avail.cond = strdup(xml_get(cur));
       } while(xml_nextNode(cur));
     }
   } while(xml_nextNode(node));
@@ -438,6 +491,11 @@ void missions_free(void) {
   free(mission_stack);
   mission_stack = NULL;
   mission_nstack = 0;
+
+  if(mission_cond_L != NULL) {
+    lua_close(mission_cond_L);
+    mission_cond_L = NULL;
+  }
 }
 
 void missions_cleanup(void) {
@@ -590,7 +648,7 @@ static int missions_parseActive(xmlNodePtr parent) {
 
       // Process the attributes to create the mission.
       xmlr_attr(node, "data", buf);
-      mission_init(misn, mission_get(mission_getID(buf)));
+      mission_init(misn, mission_get(mission_getID(buf)), 1);
       free(buf);
 
       // This will orphan an identifier.

src/mission.h

@@ -33,7 +33,7 @@ typedef struct MissionData_ {
     int* factions;
     int nfactions;
 
-    char* req; // Required variable.
+    char* cond;   // Conditional that must be met.
   } avail;
 
   unsigned int flags; // Flags to store binary properties.