# ai_instance.cpp

Go to the documentation of this file.

    00001 /* $Id: ai_instance.cpp 16835 2009-07-15 20:29:45Z rubidium $ */
    00002
    00005 #include "../stdafx.h"
    00006 #include "../debug.h"
    00007 #include "../settings_type.h"
    00008 #include "../vehicle_base.h"
    00009 #include "../saveload/saveload.h"
    00010 #include "../gui.h"
    00011 #include "table/strings.h"
    00012
    00013 #include <squirrel.h>
    00014 #include "../script/squirrel.hpp"
    00015 #include "../script/squirrel_helper.hpp"
    00016 #include "../script/squirrel_class.hpp"
    00017 #include "../script/squirrel_std.hpp"
    00018
    00019 #define DEFINE_SCRIPT_FILES
    00020
    00021 #include "ai_info.hpp"
    00022 #include "ai_config.hpp"
    00023 #include "ai_storage.hpp"
    00024 #include "ai_instance.hpp"
    00025 #include "ai_gui.hpp"
    00026
    00027 /* Convert all AI related classes to Squirrel data.
    00028  * Note: this line a marker in squirrel_export.sh. Do not change! */
    00029 #include "api/ai_abstractlist.hpp.sq"
    00030 #include "api/ai_accounting.hpp.sq"
    00031 #include "api/ai_airport.hpp.sq"
    00032 #include "api/ai_base.hpp.sq"
    00033 #include "api/ai_bridge.hpp.sq"
    00034 #include "api/ai_bridgelist.hpp.sq"
    00035 #include "api/ai_cargo.hpp.sq"
    00036 #include "api/ai_cargolist.hpp.sq"
    00037 #include "api/ai_company.hpp.sq"
    00038 #include "api/ai_controller.hpp.sq"
    00039 #include "api/ai_date.hpp.sq"
    00040 #include "api/ai_depotlist.hpp.sq"
    00041 #include "api/ai_engine.hpp.sq"
    00042 #include "api/ai_enginelist.hpp.sq"
    00043 #include "api/ai_error.hpp.sq"
    00044 #include "api/ai_event.hpp.sq"
    00045 #include "api/ai_event_types.hpp.sq"
    00046 #include "api/ai_execmode.hpp.sq"
    00047 #include "api/ai_gamesettings.hpp.sq"
    00048 #include "api/ai_group.hpp.sq"
    00049 #include "api/ai_grouplist.hpp.sq"
    00050 #include "api/ai_industry.hpp.sq"
    00051 #include "api/ai_industrylist.hpp.sq"
    00052 #include "api/ai_industrytype.hpp.sq"
    00053 #include "api/ai_industrytypelist.hpp.sq"
    00054 #include "api/ai_list.hpp.sq"
    00055 #include "api/ai_log.hpp.sq"
    00056 #include "api/ai_map.hpp.sq"
    00057 #include "api/ai_marine.hpp.sq"
    00058 #include "api/ai_order.hpp.sq"
    00059 #include "api/ai_rail.hpp.sq"
    00060 #include "api/ai_railtypelist.hpp.sq"
    00061 #include "api/ai_road.hpp.sq"
    00062 #include "api/ai_sign.hpp.sq"
    00063 #include "api/ai_signlist.hpp.sq"
    00064 #include "api/ai_station.hpp.sq"
    00065 #include "api/ai_stationlist.hpp.sq"
    00066 #include "api/ai_subsidy.hpp.sq"
    00067 #include "api/ai_subsidylist.hpp.sq"
    00068 #include "api/ai_testmode.hpp.sq"
    00069 #include "api/ai_tile.hpp.sq"
    00070 #include "api/ai_tilelist.hpp.sq"
    00071 #include "api/ai_town.hpp.sq"
    00072 #include "api/ai_townlist.hpp.sq"
    00073 #include "api/ai_tunnel.hpp.sq"
    00074 #include "api/ai_vehicle.hpp.sq"
    00075 #include "api/ai_vehiclelist.hpp.sq"
    00076 #include "api/ai_waypoint.hpp.sq"
    00077 #include "api/ai_waypointlist.hpp.sq"
    00078
    00079 #undef DEFINE_SCRIPT_FILES
    00080
    00081 /* static */ AIInstance *AIInstance::current_instance = NULL;
    00082
    00083 AIStorage::~AIStorage()
    00084 {
    00085   /* Free our pointers */
    00086   if (event_data != NULL) AIEventController::FreeEventPointer();
    00087   if (log_data != NULL) AILog::FreeLogPointer();
    00088 }
    00089
    00090 static void PrintFunc(bool error_msg, const SQChar *message)
    00091 {
    00092   /* Convert to OpenTTD internal capable string */
    00093   AIController::Print(error_msg, FS2OTTD(message));
    00094 }
    00095
    00096 AIInstance::AIInstance(AIInfo *info) :
    00097   controller(NULL),
    00098   storage(NULL),
    00099   engine(NULL),
    00100   instance(NULL),
    00101   is_started(false),
    00102   is_dead(false),
    00103   is_save_data_on_stack(false),
    00104   suspend(0),
    00105   callback(NULL)
    00106 {
    00107   /* Set the instance already, so we can use AIObject::Set commands */
    00108   GetCompany(_current_company)->ai_instance = this;
    00109   AIInstance::current_instance = this;
    00110
    00111   this->controller = new AIController();
    00112   this->storage    = new AIStorage();
    00113   this->engine     = new Squirrel();
    00114   this->engine->SetPrintFunction(&PrintFunc);
    00115
    00116   /* The import method is available at a very early stage */
    00117   this->engine->AddMethod("import", &AILibrary::Import, 4, ".ssi");
    00118
    00119   /* Register the AIController */
    00120   SQAIController_Register(this->engine);
    00121
    00122   /* Load and execute the script for this AI */
    00123   const char *main_script = info->GetMainScript();
    00124   if (strcmp(main_script, "%_dummy") == 0) {
    00125     extern void AI_CreateAIDummy(HSQUIRRELVM vm);
    00126     AI_CreateAIDummy(this->engine->GetVM());
    00127   } else if (!this->engine->LoadScript(main_script)) {
    00128     this->Died();
    00129     return;
    00130   }
    00131
    00132   /* Create the main-class */
    00133   this->instance = MallocT<SQObject>(1);
    00134   if (!this->engine->CreateClassInstance(info->GetInstanceName(), this->controller, this->instance)) {
    00135     this->Died();
    00136     return;
    00137   }
    00138
    00139   /* Register the API functions and classes */
    00140   this->RegisterAPI();
    00141 }
    00142
    00143 AIInstance::~AIInstance()
    00144 {
    00145   if (instance != NULL) this->engine->ReleaseObject(this->instance);
    00146   if (engine != NULL) delete this->engine;
    00147   delete this->storage;
    00148   delete this->controller;
    00149   free(this->instance);
    00150 }
    00151
    00152 void AIInstance::RegisterAPI()
    00153 {
    00154 /* Register all classes */
    00155   squirrel_register_std(this->engine);
    00156   SQAIAbstractList_Register(this->engine);
    00157   SQAIAccounting_Register(this->engine);
    00158   SQAIAirport_Register(this->engine);
    00159   SQAIBase_Register(this->engine);
    00160   SQAIBridge_Register(this->engine);
    00161   SQAIBridgeList_Register(this->engine);
    00162   SQAIBridgeList_Length_Register(this->engine);
    00163   SQAICargo_Register(this->engine);
    00164   SQAICargoList_Register(this->engine);
    00165   SQAICargoList_IndustryAccepting_Register(this->engine);
    00166   SQAICargoList_IndustryProducing_Register(this->engine);
    00167   SQAICompany_Register(this->engine);
    00168   SQAIDate_Register(this->engine);
    00169   SQAIDepotList_Register(this->engine);
    00170   SQAIEngine_Register(this->engine);
    00171   SQAIEngineList_Register(this->engine);
    00172   SQAIError_Register(this->engine);
    00173   SQAIEvent_Register(this->engine);
    00174   SQAIEventCompanyBankrupt_Register(this->engine);
    00175   SQAIEventCompanyInTrouble_Register(this->engine);
    00176   SQAIEventCompanyMerger_Register(this->engine);
    00177   SQAIEventCompanyNew_Register(this->engine);
    00178   SQAIEventController_Register(this->engine);
    00179   SQAIEventDisasterZeppelinerCleared_Register(this->engine);
    00180   SQAIEventDisasterZeppelinerCrashed_Register(this->engine);
    00181   SQAIEventEngineAvailable_Register(this->engine);
    00182   SQAIEventEnginePreview_Register(this->engine);
    00183   SQAIEventIndustryClose_Register(this->engine);
    00184   SQAIEventIndustryOpen_Register(this->engine);
    00185   SQAIEventStationFirstVehicle_Register(this->engine);
    00186   SQAIEventSubsidyAwarded_Register(this->engine);
    00187   SQAIEventSubsidyExpired_Register(this->engine);
    00188   SQAIEventSubsidyOffer_Register(this->engine);
    00189   SQAIEventSubsidyOfferExpired_Register(this->engine);
    00190   SQAIEventVehicleCrashed_Register(this->engine);
    00191   SQAIEventVehicleLost_Register(this->engine);
    00192   SQAIEventVehicleUnprofitable_Register(this->engine);
    00193   SQAIEventVehicleWaitingInDepot_Register(this->engine);
    00194   SQAIExecMode_Register(this->engine);
    00195   SQAIGameSettings_Register(this->engine);
    00196   SQAIGroup_Register(this->engine);
    00197   SQAIGroupList_Register(this->engine);
    00198   SQAIIndustry_Register(this->engine);
    00199   SQAIIndustryList_Register(this->engine);
    00200   SQAIIndustryList_CargoAccepting_Register(this->engine);
    00201   SQAIIndustryList_CargoProducing_Register(this->engine);
    00202   SQAIIndustryType_Register(this->engine);
    00203   SQAIIndustryTypeList_Register(this->engine);
    00204   SQAIList_Register(this->engine);
    00205   SQAILog_Register(this->engine);
    00206   SQAIMap_Register(this->engine);
    00207   SQAIMarine_Register(this->engine);
    00208   SQAIOrder_Register(this->engine);
    00209   SQAIRail_Register(this->engine);
    00210   SQAIRailTypeList_Register(this->engine);
    00211   SQAIRoad_Register(this->engine);
    00212   SQAISign_Register(this->engine);
    00213   SQAISignList_Register(this->engine);
    00214   SQAIStation_Register(this->engine);
    00215   SQAIStationList_Register(this->engine);
    00216   SQAIStationList_Vehicle_Register(this->engine);
    00217   SQAISubsidy_Register(this->engine);
    00218   SQAISubsidyList_Register(this->engine);
    00219   SQAITestMode_Register(this->engine);
    00220   SQAITile_Register(this->engine);
    00221   SQAITileList_Register(this->engine);
    00222   SQAITileList_IndustryAccepting_Register(this->engine);
    00223   SQAITileList_IndustryProducing_Register(this->engine);
    00224   SQAITileList_StationType_Register(this->engine);
    00225   SQAITown_Register(this->engine);
    00226   SQAITownList_Register(this->engine);
    00227   SQAITunnel_Register(this->engine);
    00228   SQAIVehicle_Register(this->engine);
    00229   SQAIVehicleList_Register(this->engine);
    00230   SQAIVehicleList_DefaultGroup_Register(this->engine);
    00231   SQAIVehicleList_Group_Register(this->engine);
    00232   SQAIVehicleList_SharedOrders_Register(this->engine);
    00233   SQAIVehicleList_Station_Register(this->engine);
    00234   SQAIWaypoint_Register(this->engine);
    00235   SQAIWaypointList_Register(this->engine);
    00236   SQAIWaypointList_Vehicle_Register(this->engine);
    00237
    00238   this->engine->SetGlobalPointer(this->engine);
    00239 }
    00240
    00241 void AIInstance::Continue()
    00242 {
    00243   assert(this->suspend < 0);
    00244   this->suspend = -this->suspend - 1;
    00245 }
    00246
    00247 void AIInstance::Died()
    00248 {
    00249   DEBUG(ai, 0, "The AI died unexpectedly.");
    00250   this->is_dead = true;
    00251
    00252   if (this->instance != NULL) this->engine->ReleaseObject(this->instance);
    00253   delete this->engine;
    00254   this->instance = NULL;
    00255   this->engine = NULL;
    00256
    00257   ShowAIDebugWindow(_current_company);
    00258
    00259   const AIInfo *info = AIConfig::GetConfig(_current_company)->GetInfo();
    00260   if (info != NULL) {
    00261     ShowErrorMessage(INVALID_STRING_ID, STR_AI_PLEASE_REPORT_CRASH, 0, 0);
    00262
    00263     if (info->GetURL() != NULL) {
    00264       AILog::Info("Please report the error to the following URL:");
    00265       AILog::Info(info->GetURL());
    00266     }
    00267   }
    00268 }
    00269
    00270 void AIInstance::GameLoop()
    00271 {
    00272   if (this->is_dead) return;
    00273   if (this->engine->HasScriptCrashed()) {
    00274     /* The script crashed during saving, kill it here. */
    00275     this->Died();
    00276     return;
    00277   }
    00278   this->controller->ticks++;
    00279
    00280   if (this->suspend   < -1) this->suspend++; // Multiplayer suspend, increase up to -1.
    00281   if (this->suspend   < 0)  return;          // Multiplayer suspend, wait for Continue().
    00282   if (--this->suspend > 0)  return;          // Singleplayer suspend, decrease to 0.
    00283
    00284   /* If there is a callback to call, call that first */
    00285   if (this->callback != NULL) {
    00286     if (this->is_save_data_on_stack) {
    00287       sq_poptop(this->engine->GetVM());
    00288       this->is_save_data_on_stack = false;
    00289     }
    00290     try {
    00291       this->callback(this);
    00292     } catch (AI_VMSuspend e) {
    00293       this->suspend  = e.GetSuspendTime();
    00294       this->callback = e.GetSuspendCallback();
    00295
    00296       return;
    00297     }
    00298   }
    00299
    00300   this->suspend  = 0;
    00301   this->callback = NULL;
    00302
    00303   if (!this->is_started) {
    00304     try {
    00305       AIObject::SetAllowDoCommand(false);
    00306       /* Run the constructor if it exists. Don't allow any DoCommands in it. */
    00307       if (this->engine->MethodExists(*this->instance, "constructor")) {
    00308         if (!this->engine->CallMethod(*this->instance, "constructor", 100000) || this->engine->IsSuspended()) {
    00309           if (this->engine->IsSuspended()) AILog::Error("This AI took too long to initialize. AI is not started.");
    00310           this->Died();
    00311           return;
    00312         }
    00313       }
    00314       if (!this->CallLoad() || this->engine->IsSuspended()) {
    00315         if (this->engine->IsSuspended()) AILog::Error("This AI took too long in the Load function. AI is not started.");
    00316         this->Died();
    00317         return;
    00318       }
    00319       AIObject::SetAllowDoCommand(true);
    00320       /* Start the AI by calling Start() */
    00321       if (!this->engine->CallMethod(*this->instance, "Start",  _settings_game.ai.ai_max_opcode_till_suspend) || !this->engine->IsSuspended()) this->Died();
    00322     } catch (AI_VMSuspend e) {
    00323       this->suspend  = e.GetSuspendTime();
    00324       this->callback = e.GetSuspendCallback();
    00325     }
    00326
    00327     this->is_started = true;
    00328     return;
    00329   }
    00330   if (this->is_save_data_on_stack) {
    00331     sq_poptop(this->engine->GetVM());
    00332     this->is_save_data_on_stack = false;
    00333   }
    00334
    00335   /* Continue the VM */
    00336   try {
    00337     if (!this->engine->Resume(_settings_game.ai.ai_max_opcode_till_suspend)) this->Died();
    00338   } catch (AI_VMSuspend e) {
    00339     this->suspend  = e.GetSuspendTime();
    00340     this->callback = e.GetSuspendCallback();
    00341   }
    00342 }
    00343
    00344 void AIInstance::CollectGarbage()
    00345 {
    00346   if (this->is_started && !this->is_dead) this->engine->CollectGarbage();
    00347 }
    00348
    00349 /* static */ void AIInstance::DoCommandReturn(AIInstance *instance)
    00350 {
    00351   instance->engine->InsertResult(AIObject::GetLastCommandRes());
    00352 }
    00353
    00354 /* static */ void AIInstance::DoCommandReturnVehicleID(AIInstance *instance)
    00355 {
    00356   instance->engine->InsertResult(AIObject::GetNewVehicleID());
    00357 }
    00358
    00359 /* static */ void AIInstance::DoCommandReturnSignID(AIInstance *instance)
    00360 {
    00361   instance->engine->InsertResult(AIObject::GetNewSignID());
    00362 }
    00363
    00364 /* static */ void AIInstance::DoCommandReturnGroupID(AIInstance *instance)
    00365 {
    00366   instance->engine->InsertResult(AIObject::GetNewGroupID());
    00367 }
    00368
    00369 /* static */ AIStorage *AIInstance::GetStorage()
    00370 {
    00371   assert(IsValidCompanyID(_current_company) && !IsHumanCompany(_current_company));
    00372   return GetCompany(_current_company)->ai_instance->storage;
    00373 }
    00374
    00375 /*
    00376  * All data is stored in the following format:
    00377  * First 1 byte indicating if there is a data blob at all.
    00378  * 1 byte indicating the type of data.
    00379  * The data itself, this differs per type:
    00380  *  - integer: a binary representation of the integer (int32).
    00381  *  - string:  First one byte with the string length, then a 0-terminated char
    00382  *             array. The string can't be longer then 255 bytes (including
    00383  *             terminating '\0').
    00384  *  - array:   All data-elements of the array are saved recursive in this
    00385  *             format, and ended with an element of the type
    00386  *             SQSL_ARRAY_TABLE_END.
    00387  *  - table:   All key/value pairs are saved in this format (first key 1, then
    00388  *             value 1, then key 2, etc.). All keys and values can have an
    00389  *             arbitrary type (as long as it is supported by the save function
    00390  *             of course). The table is ended with an element of the type
    00391  *             SQSL_ARRAY_TABLE_END.
    00392  *  - bool:    A single byte with value 1 representing true and 0 false.
    00393  *  - null:    No data.
    00394  */
    00395
    00397 enum SQSaveLoadType {
    00398   SQSL_INT             = 0x00,
    00399   SQSL_STRING          = 0x01,
    00400   SQSL_ARRAY           = 0x02,
    00401   SQSL_TABLE           = 0x03,
    00402   SQSL_BOOL            = 0x04,
    00403   SQSL_NULL            = 0x05,
    00404   SQSL_ARRAY_TABLE_END = 0xFF,
    00405 };
    00406
    00407 static byte _ai_sl_byte;
    00408
    00409 static const SaveLoad _ai_byte[] = {
    00410   SLEG_VAR(_ai_sl_byte, SLE_UINT8),
    00411   SLE_END()
    00412 };
    00413
    00414 enum {
    00415   AISAVE_MAX_DEPTH = 25,
    00416 };
    00417
    00418 /* static */ bool AIInstance::SaveObject(HSQUIRRELVM vm, SQInteger index, int max_depth, bool test)
    00419 {
    00420   if (max_depth == 0) {
    00421     AILog::Error("Savedata can only be nested to 25 deep. No data saved.");
    00422     return false;
    00423   }
    00424
    00425   switch (sq_gettype(vm, index)) {
    00426     case OT_INTEGER: {
    00427       if (!test) {
    00428         _ai_sl_byte = SQSL_INT;
    00429         SlObject(NULL, _ai_byte);
    00430       }
    00431       SQInteger res;
    00432       sq_getinteger(vm, index, &res);
    00433       if (!test) {
    00434         int value = (int)res;
    00435         SlArray(&value, 1, SLE_INT32);
    00436       }
    00437       return true;
    00438     }
    00439
    00440     case OT_STRING: {
    00441       if (!test) {
    00442         _ai_sl_byte = SQSL_STRING;
    00443         SlObject(NULL, _ai_byte);
    00444       }
    00445       const SQChar *res;
    00446       sq_getstring(vm, index, &res);
    00447       /* @bug if a string longer than 512 characters is given to FS2OTTD, the
    00448        *  internal buffer overflows. */
    00449       const char *buf = FS2OTTD(res);
    00450       size_t len = strlen(buf) + 1;
    00451       if (len >= 255) {
    00452         AILog::Error("Maximum string length is 254 chars. No data saved.");
    00453         return false;
    00454       }
    00455       if (!test) {
    00456         _ai_sl_byte = (byte)len;
    00457         SlObject(NULL, _ai_byte);
    00458         SlArray((void*)buf, len, SLE_CHAR);
    00459       }
    00460       return true;
    00461     }
    00462
    00463     case OT_ARRAY: {
    00464       if (!test) {
    00465         _ai_sl_byte = SQSL_ARRAY;
    00466         SlObject(NULL, _ai_byte);
    00467       }
    00468       sq_pushnull(vm);
    00469       while (SQ_SUCCEEDED(sq_next(vm, index - 1))) {
    00470         /* Store the value */
    00471         bool res = SaveObject(vm, -1, max_depth - 1, test);
    00472         sq_pop(vm, 2);
    00473         if (!res) {
    00474           sq_pop(vm, 1);
    00475           return false;
    00476         }
    00477       }
    00478       sq_pop(vm, 1);
    00479       if (!test) {
    00480         _ai_sl_byte = SQSL_ARRAY_TABLE_END;
    00481         SlObject(NULL, _ai_byte);
    00482       }
    00483       return true;
    00484     }
    00485
    00486     case OT_TABLE: {
    00487       if (!test) {
    00488         _ai_sl_byte = SQSL_TABLE;
    00489         SlObject(NULL, _ai_byte);
    00490       }
    00491       sq_pushnull(vm);
    00492       while (SQ_SUCCEEDED(sq_next(vm, index - 1))) {
    00493         /* Store the key + value */
    00494         bool res = SaveObject(vm, -2, max_depth - 1, test) && SaveObject(vm, -1, max_depth - 1, test);
    00495         sq_pop(vm, 2);
    00496         if (!res) {
    00497           sq_pop(vm, 1);
    00498           return false;
    00499         }
    00500       }
    00501       sq_pop(vm, 1);
    00502       if (!test) {
    00503         _ai_sl_byte = SQSL_ARRAY_TABLE_END;
    00504         SlObject(NULL, _ai_byte);
    00505       }
    00506       return true;
    00507     }
    00508
    00509     case OT_BOOL: {
    00510       if (!test) {
    00511         _ai_sl_byte = SQSL_BOOL;
    00512         SlObject(NULL, _ai_byte);
    00513       }
    00514       SQBool res;
    00515       sq_getbool(vm, index, &res);
    00516       if (!test) {
    00517         _ai_sl_byte = res ? 1 : 0;
    00518         SlObject(NULL, _ai_byte);
    00519       }
    00520       return true;
    00521     }
    00522
    00523     case OT_NULL: {
    00524       if (!test) {
    00525         _ai_sl_byte = SQSL_NULL;
    00526         SlObject(NULL, _ai_byte);
    00527       }
    00528       return true;
    00529     }
    00530
    00531     default:
    00532       AILog::Error("You tried to save an unsupported type. No data saved.");
    00533       return false;
    00534   }
    00535 }
    00536
    00537 /* static */ void AIInstance::SaveEmpty()
    00538 {
    00539   _ai_sl_byte = 0;
    00540   SlObject(NULL, _ai_byte);
    00541 }
    00542
    00543 void AIInstance::Save()
    00544 {
    00545   /* Don't save data if the AI didn't start yet or if it crashed. */
    00546   if (this->engine == NULL || this->engine->HasScriptCrashed()) {
    00547     SaveEmpty();
    00548     return;
    00549   }
    00550
    00551   HSQUIRRELVM vm = this->engine->GetVM();
    00552   if (this->is_save_data_on_stack) {
    00553     _ai_sl_byte = 1;
    00554     SlObject(NULL, _ai_byte);
    00555     /* Save the data that was just loaded. */
    00556     SaveObject(vm, -1, AISAVE_MAX_DEPTH, false);
    00557   } else if (!this->is_started) {
    00558     SaveEmpty();
    00559     return;
    00560   } else if (this->engine->MethodExists(*this->instance, "Save")) {
    00561     HSQOBJECT savedata;
    00562     /* We don't want to be interrupted during the save function. */
    00563     bool backup_allow = AIObject::GetAllowDoCommand();
    00564     AIObject::SetAllowDoCommand(false);
    00565     if (!this->engine->CallMethod(*this->instance, "Save", &savedata)) {
    00566       /* The script crashed in the Save function. We can't kill
    00567        * it here, but do so in the next AI tick. */
    00568       SaveEmpty();
    00569       return;
    00570     }
    00571     AIObject::SetAllowDoCommand(backup_allow);
    00572
    00573     if (!sq_istable(savedata)) {
    00574       AILog::Error("Save function should return a table.");
    00575       SaveEmpty();
    00576       this->engine->CrashOccurred();
    00577       return;
    00578     }
    00579     sq_pushobject(vm, savedata);
    00580     if (SaveObject(vm, -1, AISAVE_MAX_DEPTH, true)) {
    00581       _ai_sl_byte = 1;
    00582       SlObject(NULL, _ai_byte);
    00583       SaveObject(vm, -1, AISAVE_MAX_DEPTH, false);
    00584       this->is_save_data_on_stack = true;
    00585     } else {
    00586       SaveEmpty();
    00587       this->engine->CrashOccurred();
    00588     }
    00589   } else {
    00590     AILog::Warning("Save function is not implemented");
    00591     _ai_sl_byte = 0;
    00592     SlObject(NULL, _ai_byte);
    00593   }
    00594
    00595 }
    00596
    00597 /* static */ bool AIInstance::LoadObjects(HSQUIRRELVM vm)
    00598 {
    00599   SlObject(NULL, _ai_byte);
    00600   switch (_ai_sl_byte) {
    00601     case SQSL_INT: {
    00602       int value;
    00603       SlArray(&value, 1, SLE_INT32);
    00604       if (vm != NULL) sq_pushinteger(vm, (SQInteger)value);
    00605       return true;
    00606     }
    00607
    00608     case SQSL_STRING: {
    00609       SlObject(NULL, _ai_byte);
    00610       static char buf[256];
    00611       SlArray(buf, _ai_sl_byte, SLE_CHAR);
    00612       if (vm != NULL) sq_pushstring(vm, OTTD2FS(buf), -1);
    00613       return true;
    00614     }
    00615
    00616     case SQSL_ARRAY: {
    00617       if (vm != NULL) sq_newarray(vm, 0);
    00618       while (LoadObjects(vm)) {
    00619         if (vm != NULL) sq_arrayappend(vm, -2);
    00620         /* The value is popped from the stack by squirrel. */
    00621       }
    00622       return true;
    00623     }
    00624
    00625     case SQSL_TABLE: {
    00626       if (vm != NULL) sq_newtable(vm);
    00627       while (LoadObjects(vm)) {
    00628         LoadObjects(vm);
    00629         if (vm != NULL) sq_rawset(vm, -3);
    00630         /* The key (-2) and value (-1) are popped from the stack by squirrel. */
    00631       }
    00632       return true;
    00633     }
    00634
    00635     case SQSL_BOOL: {
    00636       SlObject(NULL, _ai_byte);
    00637       if (vm != NULL) sq_pushinteger(vm, (SQBool)(_ai_sl_byte != 0));
    00638       return true;
    00639     }
    00640
    00641     case SQSL_NULL: {
    00642       if (vm != NULL) sq_pushnull(vm);
    00643       return true;
    00644     }
    00645
    00646     case SQSL_ARRAY_TABLE_END: {
    00647       return false;
    00648     }
    00649
    00650     default: NOT_REACHED();
    00651   }
    00652 }
    00653
    00654 /* static */ void AIInstance::LoadEmpty()
    00655 {
    00656   SlObject(NULL, _ai_byte);
    00657   /* Check if there was anything saved at all. */
    00658   if (_ai_sl_byte == 0) return;
    00659
    00660   LoadObjects(NULL);
    00661 }
    00662
    00663 void AIInstance::Load(int version)
    00664 {
    00665   if (this->engine == NULL || version == -1) {
    00666     LoadEmpty();
    00667     return;
    00668   }
    00669   HSQUIRRELVM vm = this->engine->GetVM();
    00670
    00671   SlObject(NULL, _ai_byte);
    00672   /* Check if there was anything saved at all. */
    00673   if (_ai_sl_byte == 0) return;
    00674
    00675   sq_pushinteger(vm, version);
    00676   LoadObjects(vm);
    00677   this->is_save_data_on_stack = true;
    00678 }
    00679
    00680 bool AIInstance::CallLoad()
    00681 {
    00682   HSQUIRRELVM vm = this->engine->GetVM();
    00683   /* Is there save data that we should load? */
    00684   if (!this->is_save_data_on_stack) return true;
    00685   /* Whatever happens, after CallLoad the savegame data is removed from the stack. */
    00686   this->is_save_data_on_stack = false;
    00687
    00688   if (!this->engine->MethodExists(*this->instance, "Load")) {
    00689     AILog::Warning("Loading failed: there was data for the AI to load, but the AI does not have a Load() function.");
    00690
    00691     /* Pop the savegame data and version. */
    00692     sq_pop(vm, 2);
    00693     return true;
    00694   }
    00695
    00696   /* Go to the instance-root */
    00697   sq_pushobject(vm, *this->instance);
    00698   /* Find the function-name inside the script */
    00699   sq_pushstring(vm, OTTD2FS("Load"), -1);
    00700   /* Change the "Load" string in a function pointer */
    00701   sq_get(vm, -2);
    00702   /* Push the main instance as "this" object */
    00703   sq_pushobject(vm, *this->instance);
    00704   /* Push the version data and savegame data as arguments */
    00705   sq_push(vm, -5);
    00706   sq_push(vm, -5);
    00707
    00708   /* Call the AI load function. sq_call removes the arguments (but not the
    00709    * function pointer) from the stack. */
    00710   if (SQ_FAILED(sq_call(vm, 3, SQFalse, SQFalse, 100000))) return false;
    00711
    00712   /* Pop 1) The version, 2) the savegame data, 3) the object instance, 4) the function pointer. */
    00713   sq_pop(vm, 4);
    00714   return true;
    00715 }