Moved the managing of NPC script coroutines into C++

Rather than wrapping NPC functions up in coroutines in the Lua side, they
are now managed on the C++ side as "script threads", which are essentially
the same thing.

The main purpose is that the server can now know whether any of these long
running script interactions are still active, which will probably be useful
when adding the ability to reload scripts.

Reviewed-by: Erik Schilling

1 files changed, 55 insertions, 82 deletions

diff --git a/src/scripting/lua.cpp b/src/scripting/lua.cpp
index 540925b1..5053070a 100644
--- a/src/scripting/lua.cpp
+++ b/src/scripting/lua.cpp
@@ -91,20 +91,6 @@ static int on_character_death_accept(lua_State *s)
     return 0;
 }
 
-static int on_npc_quest_reply(lua_State *s)
-{
-    luaL_checktype(s, 1, LUA_TFUNCTION);
-    LuaScript::setQuestReplyCallback(getScript(s));
-    return 0;
-}
-
-static int on_npc_post_reply(lua_State *s)
-{
-    luaL_checktype(s, 1, LUA_TFUNCTION);
-    LuaScript::setPostReplyCallback(getScript(s));
-    return 0;
-}
-
 static int on_being_death(lua_State *s)
 {
     luaL_checktype(s, 1, LUA_TFUNCTION);
@@ -133,34 +119,6 @@ static int on_npc_start(lua_State *s)
     return 0;
 }
 
-static int on_npc_next(lua_State *s)
-{
-    luaL_checktype(s, 1, LUA_TFUNCTION);
-    NPC::setNextCallback(getScript(s));
-    return 0;
-}
-
-static int on_npc_choose(lua_State *s)
-{
-    luaL_checktype(s, 1, LUA_TFUNCTION);
-    NPC::setChooseCallback(getScript(s));
-    return 0;
-}
-
-static int on_npc_integer(lua_State *s)
-{
-    luaL_checktype(s, 1, LUA_TFUNCTION);
-    NPC::setIntegerCallback(getScript(s));
-    return 0;
-}
-
-static int on_npc_string(lua_State *s)
-{
-    luaL_checktype(s, 1, LUA_TFUNCTION);
-    NPC::setStringCallback(getScript(s));
-    return 0;
-}
-
 static int on_npc_update(lua_State *s)
 {
     luaL_checktype(s, 1, LUA_TFUNCTION);
@@ -233,11 +191,15 @@ static int npc_message(lua_State *s)
     size_t l;
     const char *m = luaL_checklstring(s, 3, &l);
 
+    Script::Thread *thread = checkCurrentThread(s);
+
     MessageOut msg(GPMSG_NPC_MESSAGE);
     msg.writeInt16(p->getPublicID());
     msg.writeString(m, l);
     gameHandler->sendTo(q, msg);
-    return 0;
+
+    thread->mState = Script::ThreadPaused;
+    return lua_yield(s, 0);
 }
 
 /**
@@ -249,6 +211,8 @@ static int npc_choice(lua_State *s)
     NPC *p = checkNPC(s, 1);
     Character *q = checkCharacter(s, 2);
 
+    Script::Thread *thread = checkCurrentThread(s);
+
     MessageOut msg(GPMSG_NPC_CHOICE);
     msg.writeInt16(p->getPublicID());
     for (int i = 3, i_end = lua_gettop(s); i <= i_end; ++i)
@@ -282,11 +246,13 @@ static int npc_choice(lua_State *s)
         }
     }
     gameHandler->sendTo(q, msg);
-    return 0;
+
+    thread->mState = Script::ThreadExpectingNumber;
+    return lua_yield(s, 0);
 }
 
 /**
- * mana.npc_integer(NPC*, Character*, int min, int max, int defaut = min): void
+ * mana.npc_integer(NPC*, Character*, int min, int max, int default = min): void
  * Callback for sending a NPC_INTEGER.
  */
 static int npc_ask_integer(lua_State *s)
@@ -297,6 +263,8 @@ static int npc_ask_integer(lua_State *s)
     int max = luaL_checkint(s, 4);
     int defaultValue = luaL_optint(s, 5, min);
 
+    Script::Thread *thread = checkCurrentThread(s);
+
     MessageOut msg(GPMSG_NPC_NUMBER);
     msg.writeInt16(p->getPublicID());
     msg.writeInt32(min);
@@ -304,7 +272,8 @@ static int npc_ask_integer(lua_State *s)
     msg.writeInt32(defaultValue);
     gameHandler->sendTo(q, msg);
 
-    return 0;
+    thread->mState = Script::ThreadExpectingNumber;
+    return lua_yield(s, 0);
 }
 
 /**
@@ -316,15 +285,18 @@ static int npc_ask_string(lua_State *s)
     NPC *p = checkNPC(s, 1);
     Character *q = checkCharacter(s, 2);
 
+    Script::Thread *thread = checkCurrentThread(s);
+
     MessageOut msg(GPMSG_NPC_STRING);
     msg.writeInt16(p->getPublicID());
     gameHandler->sendTo(q, msg);
 
-    return 0;
+    thread->mState = Script::ThreadExpectingString;
+    return lua_yield(s, 0);
 }
 
 /**
- * mana.npc_create(string name, int id, int x, int y): NPC*
+ * mana.npc_create(string name, int id, int gender, int x, int y): NPC*
  * Callback for creating a NPC on the current map with the current script.
  */
 static int npc_create(lua_State *s)
@@ -335,10 +307,9 @@ static int npc_create(lua_State *s)
     const int x = luaL_checkint(s, 4);
     const int y = luaL_checkint(s, 5);
 
-    Script *t = getScript(s);
-    MapComposite *m = checkCurrentMap(s, t);
+    MapComposite *m = checkCurrentMap(s);
 
-    NPC *q = new NPC(name, id, t);
+    NPC *q = new NPC(name, id);
     q->setGender(getGender(gender));
     q->setMap(m);
     q->setPosition(Point(x, y));
@@ -514,7 +485,7 @@ static int chr_get_inventory(lua_State *s)
 }
 
 /**
- * Callback for gathering equiupment information.
+ * Callback for gathering equipment information.
  * mana.chr_get_inventory(character): table[](slot, item id, name)
  * Returns in the inventory slots order, the slot id, the item ids, and name.
  * Only slots not empty are returned.
@@ -1295,6 +1266,8 @@ static int chr_get_quest(lua_State *s)
     const char *name = luaL_checkstring(s, 2);
     luaL_argcheck(s, name[0] != 0, 2, "empty variable name");
 
+    Script::Thread *thread = checkCurrentThread(s);
+
     std::string value;
     bool res = getQuestVar(q, name, value);
     if (res)
@@ -1304,7 +1277,9 @@ static int chr_get_quest(lua_State *s)
     }
     QuestCallback f = { &LuaScript::getQuestCallback, getScript(s) };
     recoverQuestVar(q, name, f);
-    return 0;
+
+    thread->mState = Script::ThreadExpectingString;
+    return lua_yield(s, 0);
 }
 
 /**
@@ -1507,8 +1482,7 @@ static int get_beings_in_rectangle(lua_State *s)
     int tableStackPosition = lua_gettop(s);
     int tableIndex = 1;
     Rectangle rect = {x, y ,w, h};
-    for (BeingIterator i(
-         m->getInsideRectangleIterator(rect)); i; ++i)
+    for (BeingIterator i(m->getInsideRectangleIterator(rect)); i; ++i)
     {
         Being *b = *i;
         char t = b->getType();
@@ -1530,10 +1504,14 @@ static int chr_get_post(lua_State *s)
 {
     Character *c = checkCharacter(s, 1);
 
-    PostCallback f = { &LuaScript::getPostCallback, getScript(s) };
+    Script *script = getScript(s);
+    Script::Thread *thread = checkCurrentThread(s, script);
+
+    PostCallback f = { &LuaScript::getPostCallback, script };
     postMan->getPost(c, f);
 
-    return 0;
+    thread->mState = Script::ThreadExpectingTwoStrings;
+    return lua_yield(s, 0);
 }
 
 /**
@@ -2135,31 +2113,26 @@ static int require_loader(lua_State *s)
 LuaScript::LuaScript():
     nbArgs(-1)
 {
-    mState = luaL_newstate();
-    luaL_openlibs(mState);
+    mRootState = luaL_newstate();
+    mCurrentState = mRootState;
+    luaL_openlibs(mRootState);
 
     // Register package loader that goes through the resource manager
     // table.insert(package.loaders, 2, require_loader)
-    lua_getglobal(mState, "package");
-    lua_getfield(mState, -1, "loaders");
-    lua_pushcfunction(mState, require_loader);
-    lua_rawseti(mState, -2, 2);
-    lua_pop(mState, 2);
+    lua_getglobal(mRootState, "package");
+    lua_getfield(mRootState, -1, "loaders");
+    lua_pushcfunction(mRootState, require_loader);
+    lua_rawseti(mRootState, -2, 2);
+    lua_pop(mRootState, 2);
 
     // Put the callback functions in the scripting environment.
     static luaL_Reg const callbacks[] = {
         { "on_character_death",              &on_character_death              },
         { "on_character_death_accept",       &on_character_death_accept       },
-        { "on_npc_quest_reply",              &on_npc_quest_reply              },
-        { "on_npc_post_reply",               &on_npc_post_reply               },
         { "on_being_death",                  &on_being_death                  },
         { "on_being_remove",                 &on_being_remove                 },
         { "on_update",                       &on_update                       },
         { "on_npc_start",                    &on_npc_start                    },
-        { "on_npc_next",                     &on_npc_next                     },
-        { "on_npc_choose",                   &on_npc_choose                   },
-        { "on_npc_integer",                  &on_npc_integer                  },
-        { "on_npc_string",                   &on_npc_string                   },
         { "on_npc_update",                   &on_npc_update                   },
         { "on_create_npc_delayed",           &on_create_npc_delayed           },
         { "on_map_initialize",               &on_map_initialize               },
@@ -2256,8 +2229,8 @@ LuaScript::LuaScript():
         { "announce",                        &announce                        },
         { NULL, NULL }
     };
-    luaL_register(mState, "mana", callbacks);
-    lua_pop(mState, 1);                     // pop the 'mana' table
+    luaL_register(mRootState, "mana", callbacks);
+    lua_pop(mRootState, 1);                     // pop the 'mana' table
 
     static luaL_Reg const members_ItemClass[] = {
         { "on",                              &item_class_on                   },
@@ -2283,20 +2256,20 @@ LuaScript::LuaScript():
         { NULL, NULL }
     };
 
-    LuaItemClass::registerType(mState, "ItemClass", members_ItemClass);
-    LuaMapObject::registerType(mState, "MapObject", members_MapObject);
-    LuaMonsterClass::registerType(mState, "MonsterClass", members_MonsterClass);
-    LuaStatusEffect::registerType(mState, "StatusEffect", members_StatusEffect);
+    LuaItemClass::registerType(mRootState, "ItemClass", members_ItemClass);
+    LuaMapObject::registerType(mRootState, "MapObject", members_MapObject);
+    LuaMonsterClass::registerType(mRootState, "MonsterClass", members_MonsterClass);
+    LuaStatusEffect::registerType(mRootState, "StatusEffect", members_StatusEffect);
 
     // Make script object available to callback functions.
-    lua_pushlightuserdata(mState, const_cast<char *>(&registryKey));
-    lua_pushlightuserdata(mState, this);
-    lua_rawset(mState, LUA_REGISTRYINDEX);
+    lua_pushlightuserdata(mRootState, const_cast<char *>(&registryKey));
+    lua_pushlightuserdata(mRootState, this);
+    lua_rawset(mRootState, LUA_REGISTRYINDEX);
 
     // Push the error handler to first index of the stack
-    lua_getglobal(mState, "debug");
-    lua_getfield(mState, -1, "traceback");
-    lua_remove(mState, 1);                  // remove the 'debug' table
+    lua_getglobal(mRootState, "debug");
+    lua_getfield(mRootState, -1, "traceback");
+    lua_remove(mRootState, 1);                  // remove the 'debug' table
 
     loadFile("scripts/lua/libmana.lua");
 }