# ai_info_dummy.cpp

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    00001 /* $Id$ */
    00002
    00003 /*
    00004  * This file is part of OpenTTD.
    00005  * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
    00006  * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
    00007  * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
    00008  */
    00009
    00012 #include <squirrel.h>
    00013 #include "../stdafx.h"
    00014
    00015 #include "../string_func.h"
    00016 #include "../strings_func.h"
    00017 #include "table/strings.h"
    00018
    00019 /* The reason this exists in C++, is that a user can trash his ai/ dir,
    00020  *  leaving no AIs available. The complexity to solve this is insane, and
    00021  *  therefor the alternative is used, and make sure there is always an AI
    00022  *  available, no matter what the situation is. By defining it in C++, there
    00023  *  is simply now way a user can delete it, and therefor safe to use. It has
    00024  *  to be noted that this AI is complete invisible for the user, and impossible
    00025  *  to select manual. It is a fail-over in case no AIs are available.
    00026  */
    00027
    00029 const SQChar _dummy_script_info[] = _SC("                                                       \n\
    00030 class DummyAI extends AIInfo {                                                                  \n\
    00031   function GetAuthor()      { return \"OpenTTD NoAI Developers Team\"; }                        \n\
    00032   function GetName()        { return \"DummyAI\"; }                                             \n\
    00033   function GetShortName()   { return \"DUMM\"; }                                                \n\
    00034   function GetDescription() { return \"A Dummy AI that is loaded when your ai/ dir is empty\"; }\n\
    00035   function GetVersion()     { return 1; }                                                       \n\
    00036   function GetDate()        { return \"2008-07-26\"; }                                          \n\
    00037   function CreateInstance() { return \"DummyAI\"; }                                             \n\
    00038 }                                                                                               \n\
    00039                                                                                                 \n\
    00040 RegisterDummyAI(DummyAI());                                                                     \n\
    00041 ");
    00042
    00044 void AI_CreateAIInfoDummy(HSQUIRRELVM vm)
    00045 {
    00046   sq_pushroottable(vm);
    00047
    00048   /* Load and run the script */
    00049   if (SQ_SUCCEEDED(sq_compilebuffer(vm, _dummy_script_info, scstrlen(_dummy_script_info), _SC("dummy"), SQTrue))) {
    00050     sq_push(vm, -2);
    00051     if (SQ_SUCCEEDED(sq_call(vm, 1, SQFalse, SQTrue))) {
    00052       sq_pop(vm, 1);
    00053       return;
    00054     }
    00055   }
    00056   NOT_REACHED();
    00057 }
    00058
    00060 void AI_CreateAIDummy(HSQUIRRELVM vm)
    00061 {
    00062   /* We want to translate the error message.
    00063    * We do this in three steps:
    00064    * 1) We get the error message
    00065    */
    00066   char error_message[1024];
    00067   GetString(error_message, STR_ERROR_AI_NO_AI_FOUND, lastof(error_message));
    00068
    00069   /* Make escapes for all quotes and slashes. */
    00070   char safe_error_message[1024];
    00071   char *q = safe_error_message;
    00072   for (const char *p = error_message; *p != '\0' && q < lastof(safe_error_message) - 2; p++, q++) {
    00073     if (*p == '"' || *p == '\\') *q++ = '\\';
    00074     *q = *p;
    00075   }
    00076   *q = '\0';
    00077
    00078   /* 2) We construct the AI's code. This is done by merging a header, body and footer */
    00079   char dummy_script[4096];
    00080   char *dp = dummy_script;
    00081   dp = strecpy(dp, "class DummyAI extends AIController {\n  function Start()\n  {\n", lastof(dummy_script));
    00082
    00083   /* As special trick we need to split the error message on newlines and
    00084    * emit each newline as a separate error printing string. */
    00085   char *newline;
    00086   char *p = safe_error_message;
    00087   do {
    00088     newline = strchr(p, '\n');
    00089     if (newline != NULL) *newline = '\0';
    00090
    00091     dp += seprintf(dp, lastof(dummy_script), "    AILog.Error(\"%s\");\n", p);
    00092     p = newline + 1;
    00093   } while (newline != NULL);
    00094
    00095   dp = strecpy(dp, "  }\n}\n", lastof(dummy_script));
    00096
    00097   /* 3) We translate the error message in the character format that Squirrel wants.
    00098    *    We can use the fact that the wchar string printing also uses %s to print
    00099    *    old style char strings, which is what was generated during the script generation. */
    00100   const SQChar *sq_dummy_script = OTTD2SQ(dummy_script);
    00101
    00102   /* And finally we load and run the script */
    00103   sq_pushroottable(vm);
    00104   if (SQ_SUCCEEDED(sq_compilebuffer(vm, sq_dummy_script, scstrlen(sq_dummy_script), _SC("dummy"), SQTrue))) {
    00105     sq_push(vm, -2);
    00106     if (SQ_SUCCEEDED(sq_call(vm, 1, SQFalse, SQTrue))) {
    00107       sq_pop(vm, 1);
    00108       return;
    00109     }
    00110   }
    00111   NOT_REACHED();
    00112 }