src/loader/Interpreter.cpp

   1 #include "Interpreter.h"
   2
   3 #include "ParsedSource.h"
   4 #include "../battle/Hero.h"
   5 #include "../battle/Monster.h"
   6 #include "../battle/PartyLayout.h"
   7 #include "../battle/Resources.h"
   8 #include "../common/Ikari.h"
   9 #include "../common/Item.h"
  10 #include "../common/Script.h"
  11 #include "../common/Spell.h"
  12 #include "../common/Stats.h"
  13 #include "../common/TargetingMode.h"
  14 #include "../graphics/ComplexAnimation.h"
  15 #include "../graphics/Font.h"
  16 #include "../graphics/Frame.h"
  17 #include "../graphics/Gauge.h"
  18 #include "../graphics/Menu.h"
  19 #include "../graphics/SimpleAnimation.h"
  20 #include "../graphics/Sprite.h"
  21
  22 #include <algorithm>
  23 #include <cstring>
  24 #include <SDL_image.h>
  25
  26 using battle::Hero;
  27 using battle::Monster;
  28 using battle::PartyLayout;
  29 using common::Ikari;
  30 using common::Item;
  31 using common::Script;
  32 using common::Spell;
  33 using common::Stats;
  34 using common::TargetingMode;
  35 using graphics::Animation;
  36 using graphics::Color;
  37 using graphics::Font;
  38 using graphics::Frame;
  39 using graphics::Gauge;
  40 using graphics::ComplexAnimation;
  41 using graphics::SimpleAnimation;
  42 using graphics::Sprite;
  43 using geometry::Vector;
  44 using std::make_pair;
  45 using std::set;
  46 using std::string;
  47 using std::vector;
  48
  49 namespace loader {
  50
  51 Interpreter::~Interpreter() {
  52         for (std::map<string, SDL_Surface *>::const_iterator i(imageCache.begin()), end(imageCache.end()); i != end; ++i) {
  53                 SDL_FreeSurface(i->second);
  54         }
  55 }
  56
  57
  58 const Interpreter::ParsedDefinition &Interpreter::GetDefinition(const string &identifier) {
  59         std::map<string, ParsedDefinition>::const_iterator i(parsedDefinitions.find(identifier));
  60         if (i != parsedDefinitions.end()) {
  61                 return i->second;
  62         } else if (source.IsDefined(identifier)) {
  63                 ReadDefinition(source.GetDefinition(identifier));
  64                 return parsedDefinitions.at(identifier);
  65         } else {
  66                 throw Error("access to undefined object " + identifier);
  67         }
  68 }
  69
  70
  71 void *Interpreter::GetObject(int typeId, const std::string &name) {
  72         std::map<string, ParsedDefinition>::const_iterator i(parsedDefinitions.find(name));
  73         if (i != parsedDefinitions.end()) {
  74                 const TypeDescription &requested(TypeDescription::Get(typeId));
  75                 const TypeDescription &actual(TypeDescription::Get(i->second.type));
  76                 if (requested.TypeId() == actual.TypeId()) {
  77                         return values[actual.TypeId()][i->second.id];
  78                 } else if (actual.IsSubtypeOf(requested)) {
  79                         char *sub(reinterpret_cast<char *>(values[actual.TypeId()][i->second.id]));
  80                         std::ptrdiff_t offset(actual.SupertypeOffset(requested));
  81                         return sub - offset;
  82                 } else {
  83                         throw Error("cannot cast " + actual.TypeName() + " to " + requested.TypeName());
  84                 }
  85         } else {
  86                 throw Error("access to undefined object " + name);
  87         }
  88 }
  89
  90
  91 void Interpreter::ReadSource() {
  92         for (set<string>::const_iterator i(source.Exports().begin()), end(source.Exports().end()); i != end; ++i) {
  93                 ReadDefinition(source.GetDefinition(*i));
  94         }
  95 }
  96
  97 void Interpreter::ReadDefinition(const Definition &dfn) {
  98         if (parsedDefinitions.find(dfn.Identifier()) != parsedDefinitions.end()) {
  99                 return;
 100         }
 101         if (dfn.HasLiteralValue()) {
 102                 ReadLiteral(dfn);
 103         } else {
 104                 ReadObject(dfn);
 105         }
 106 }
 107
 108 void Interpreter::ReadLiteral(const Definition &dfn) {
 109         const string &typeName(dfn.GetLiteral()->IsArray() ? "Array" : dfn.GetLiteral()->GetTypeName());
 110         int typeId(TypeDescription::GetTypeId(typeName));
 111         int id(values[typeId].size());
 112         const TypeDescription &td(TypeDescription::Get(typeId));
 113         int size(
 114                         (dfn.GetLiteral()->GetType() == Literal::PATH
 115                                         || dfn.GetLiteral()->GetType() == Literal::STRING)
 116                         ? dfn.GetLiteral()->GetString().size() : td.Size());
 117         char *object(alloc.Alloc(size));
 118         values[typeId].push_back(object);
 119         parsedDefinitions.insert(make_pair(dfn.Identifier(), ParsedDefinition(&dfn, typeId, id)));
 120         if (dfn.GetLiteral()->GetType() == Literal::OBJECT) {
 121                 ReadObject(typeId, id, object, *dfn.GetLiteral()->GetProperties());
 122         } else {
 123                 ReadLiteral(typeId, id, object, *dfn.GetLiteral());
 124         }
 125 }
 126
 127 void Interpreter::ReadLiteral(int typeId, int id, char *object, const Literal &literal) {
 128         switch (literal.GetType()) {
 129                 case Literal::ARRAY_VALUES:
 130                         throw Error("named value arrays are not supported, sorry");
 131                         break;
 132                 case Literal::ARRAY_PROPS:
 133                         throw Error("named property list arrays are not supported, sorry");
 134                         break;
 135                 case Literal::BOOLEAN:
 136                         new (object) bool(literal.GetBoolean());
 137                         break;
 138                 case Literal::COLOR:
 139                         new (object) Color(literal.GetRed(), literal.GetGreen(), literal.GetBlue(), literal.GetAlpha());
 140                         break;
 141                 case Literal::NUMBER:
 142                         new (object) int(literal.GetNumber());
 143                         break;
 144                 case Literal::PATH:
 145                         std::memcpy(object, literal.GetString().c_str(), literal.GetString().size());
 146                         object[literal.GetString().size()] = '\0';
 147                         break;
 148                 case Literal::SCRIPT:
 149                         new (object) Script;
 150                         ReadScript(literal.GetScript(), reinterpret_cast<Script *>(object));
 151                         break;
 152                 case Literal::STRING:
 153                         std::memcpy(object, literal.GetString().c_str(), literal.GetString().size());
 154                         object[literal.GetString().size()] = '\0';
 155                         break;
 156                 case Literal::VECTOR:
 157                         new (object) Vector<int>(literal.GetX(), literal.GetY());
 158                         break;
 159                 case Literal::OBJECT:
 160                         throw Error("illogical branch: read literal object as non-object literal");
 161         }
 162 }
 163
 164
 165 void *Interpreter::GetObject(int typeId, const Value &v) {
 166         if (v.IsLiteral()) {
 167                 if (v.GetLiteral().IsObject()) {
 168                         int typeId(TypeDescription::GetTypeId(v.GetLiteral().GetTypeName()));
 169                         const TypeDescription &td(TypeDescription::Get(typeId));
 170                         char *object(alloc.Alloc(td.Size()));
 171                         td.Construct(object);
 172                         int id(values[typeId].size());
 173                         values[typeId].push_back(object);
 174                         ReadObject(typeId, id, object, *v.GetLiteral().GetProperties());
 175                         return object;
 176                 } else {
 177                         int typeId(0), id(0);
 178                         switch (v.GetLiteral().GetType()) {
 179                                 case Literal::ARRAY_VALUES:
 180                                         throw Error("cannot copy value arrays, sorry");
 181                                         break;
 182                                 case Literal::ARRAY_PROPS:
 183                                         throw Error("cannot copy property list arrays, sorry");
 184                                         break;
 185                                 case Literal::BOOLEAN:
 186                                         {
 187                                                 typeId = TypeDescription::GetTypeId("Boolean");
 188                                                 id = values[typeId].size();
 189                                                 const TypeDescription &td(TypeDescription::Get(typeId));
 190                                                 char *object(alloc.Alloc(td.Size()));
 191                                                 values[typeId].push_back(new (object) bool(v.GetLiteral().GetBoolean()));
 192                                         }
 193                                         break;
 194                                 case Literal::COLOR:
 195                                         {
 196                                                 typeId = TypeDescription::GetTypeId("Color");
 197                                                 id = values[typeId].size();
 198                                                 const TypeDescription &td(TypeDescription::Get(typeId));
 199                                                 char *object(alloc.Alloc(td.Size()));
 200                                                 values[typeId].push_back(new (object) Color(v.GetLiteral().GetRed(), v.GetLiteral().GetGreen(), v.GetLiteral().GetBlue(), v.GetLiteral().GetAlpha()));
 201                                         }
 202                                         break;
 203                                 case Literal::NUMBER:
 204                                         {
 205                                                 typeId = TypeDescription::GetTypeId("Number");
 206                                                 id = values[typeId].size();
 207                                                 const TypeDescription &td(TypeDescription::Get(typeId));
 208                                                 char *object(alloc.Alloc(td.Size()));
 209                                                 values[typeId].push_back(new (object) int(v.GetLiteral().GetNumber()));
 210                                         }
 211                                         break;
 212                                 case Literal::PATH:
 213                                         {
 214                                                 typeId = TypeDescription::GetTypeId("Path");
 215                                                 id = values[typeId].size();
 216                                                 char *str(alloc.Alloc(v.GetLiteral().GetString().size() + 1));
 217                                                 std::memcpy(str, v.GetLiteral().GetString().c_str(), v.GetLiteral().GetString().size());
 218                                                 str[v.GetLiteral().GetString().size()] = '\0';
 219                                                 values[typeId].push_back(str);
 220                                         }
 221                                         break;
 222                                 case Literal::SCRIPT:
 223                                         {
 224                                                 typeId = TypeDescription::GetTypeId("Script");
 225                                                 char *script(ReadScript(v.GetLiteral().GetScript()));
 226                                                 id = values[typeId].size();
 227                                                 values[typeId].push_back(script);
 228                                         }
 229                                         break;
 230                                 case Literal::STRING:
 231                                         {
 232                                                 typeId = TypeDescription::GetTypeId("String");
 233                                                 id = values[typeId].size();
 234                                                 char *str(alloc.Alloc(v.GetLiteral().GetString().size() + 1));
 235                                                 std::memcpy(str, v.GetLiteral().GetString().c_str(), v.GetLiteral().GetString().size());
 236                                                 str[v.GetLiteral().GetString().size()] = '\0';
 237                                                 values[typeId].push_back(str);
 238                                         }
 239                                         break;
 240                                 case Literal::VECTOR:
 241                                         {
 242                                                 typeId = TypeDescription::GetTypeId("Vector");
 243                                                 id = values[typeId].size();
 244                                                 const TypeDescription &td(TypeDescription::Get(typeId));
 245                                                 char *object(alloc.Alloc(td.Size()));
 246                                                 values[typeId].push_back(new (object) Vector<int>(v.GetLiteral().GetX(), v.GetLiteral().GetY()));
 247                                         }
 248                                         break;
 249                                 case Literal::OBJECT:
 250                                         {
 251                                                 typeId = TypeDescription::GetTypeId(v.GetLiteral().GetTypeName());
 252                                                 const TypeDescription &td(TypeDescription::Get(typeId));
 253                                                 id = values[typeId].size();
 254                                                 char *object(alloc.Alloc(td.Size()));
 255                                                 td.Construct(object);
 256                                                 ReadObject(typeId, id, object, *v.GetLiteral().GetProperties());
 257                                         }
 258                                         break;
 259                         }
 260                         return values[typeId][id];
 261                 }
 262         } else {
 263                 ReadDefinition(source.GetDefinition(v.GetIdentifier()));
 264                 return GetObject(typeId, v.GetIdentifier());
 265         }
 266 }
 267
 268
 269 void Interpreter::ReadObject(const Definition &dfn) {
 270         int typeId(TypeDescription::GetTypeId(dfn.TypeName()));
 271         const TypeDescription &td(TypeDescription::Get(typeId));
 272         int id(values[typeId].size());
 273         char *object(alloc.Alloc(td.Size()));
 274         td.Construct(object);
 275         values[typeId].push_back(object);
 276         parsedDefinitions.insert(make_pair(dfn.Identifier(), ParsedDefinition(&dfn, typeId, id)));
 277         ReadObject(typeId, id, object, *dfn.GetProperties());
 278 }
 279
 280
 281 void Interpreter::ReadObject(int typeId, int id, char *object, const PropertyList &props) {
 282         const TypeDescription &td(TypeDescription::Get(typeId));
 283         for (PropertyList::ConstIterator i(props.Begin()), end(props.End()); i != end; ++i) {
 284                 const FieldDescription &fd(td.GetField(i->first));
 285                 const TypeDescription &fieldType(TypeDescription::Get(fd.TypeId()));
 286                 if (CanLink(*i->second)) {
 287                         char *dest(object + fd.Offset());
 288                         if (fd.IsAggregate()) {
 289                                 int arraySize(i->second->GetLiteral().ArraySize());
 290                                 char *aggregate(alloc.Alloc(fieldType.Size() * arraySize));
 291                                 char *iter(aggregate);
 292                                 if (i->second->GetLiteral().GetType() == Literal::ARRAY_PROPS) {
 293                                         const vector<PropertyList *> &list(i->second->GetLiteral().GetPropertyLists());
 294                                         for (vector<PropertyList *>::const_iterator j(list.begin()), end(list.end()); j != end; ++j, iter += fieldType.Size()) {
 295                                                 fieldType.Construct(iter);
 296                                                 ReadObject(fieldType.TypeId(), -1, iter, **j);
 297                                         }
 298                                 } else {
 299                                         const vector<Value *> &list(i->second->GetLiteral().GetValues());
 300                                         for (vector<Value *>::const_iterator j(list.begin()), end(list.end()); j != end; ++j, iter += fieldType.Size()) {
 301                                                 fieldType.Construct(iter);
 302                                                 ReadLiteral(fieldType.TypeId(), -1, iter, (*j)->GetLiteral());
 303                                         }
 304                                 }
 305                                 if (fd.IsReferenced()) {
 306                                         std::memcpy(dest, &aggregate, sizeof(char *));
 307                                         dest += sizeof(char *);
 308                                         std::memcpy(dest, &arraySize, sizeof(int));
 309                                 } else {
 310                                         throw Error("aggregate type fields must be referenced");
 311                                 }
 312                         } else if (i->second->IsLiteral() && !fd.IsReferenced()) {
 313                                 // inline literals
 314                                 if (i->second->GetLiteral().IsObject()) {
 315                                         ReadObject(fd.TypeId(), -1, dest, *i->second->GetLiteral().GetProperties());
 316                                 } else {
 317                                         ReadLiteral(fd.TypeId(), -1, dest, i->second->GetLiteral());
 318                                 }
 319                         } else {
 320                                 char *src(reinterpret_cast<char *>(GetObject(fd.TypeId(), *i->second)));
 321                                 if (fd.TypeId() == TypeDescription::GetTypeId("Image")) {
 322                                         src = reinterpret_cast<char *>(GetImage(src));
 323                                 }
 324                                 if (fd.IsReferenced()) {
 325                                         std::memcpy(dest, &src, sizeof(char *));
 326                                 } else {
 327                                         std::memcpy(dest, src, fieldType.Size());
 328                                 }
 329                         }
 330                 } else {
 331                         Postpone(typeId, id, fd.Offset(), i->second->GetIdentifier(), fd.TypeId(), !fd.IsReferenced());
 332                 }
 333         }
 334         td.Load(object);
 335 }
 336
 337
 338 void Interpreter::ReadScript(const std::vector<ScriptToken *> &s, Script *script) {
 339         std::map<string, int> labels;
 340         int size(0);
 341         for (vector<ScriptToken *>::const_iterator i(s.begin()), end(s.end()); i != end; ++i) {
 342                 if ((*i)->GetType() == ScriptToken::LABEL) {
 343                         if (labels.count((*i)->Label())) {
 344                                 throw Error("duplicate label " + (*i)->Label());
 345                         } else {
 346                                 labels[(*i)->Label()] = size;
 347                         }
 348                 } else if ((*i)->GetType() != ScriptToken::COMMAND) {
 349                         throw Error("unexpected script token");
 350                 }
 351                 size += sizeof(Script::Code);
 352                 const string &cmd((*i)->CommandName());
 353                 if (cmd == "move") {
 354                         ++i;
 355                         if (i == end) {
 356                                 throw Error("unexpected script end after move");
 357                         }
 358                         const string &reg((*i)->RegisterName());
 359                         if (reg.size() != 2) {
 360                                 throw Error("invalid register name " + reg);
 361                         }
 362                         ++i;
 363                         if (i == end) {
 364                                 throw Error("unexpected script end after move");
 365                         }
 366                         if ((*i)->GetType() != ScriptToken::REGISTER) {
 367                                 switch (reg[0]) {
 368                                         case 'a':
 369                                                 size += sizeof(void *);
 370                                                 break;
 371                                         case 'i':
 372                                                 size += sizeof(int);
 373                                                 break;
 374                                         case 'v':
 375                                                 size += sizeof(Vector<int>);
 376                                                 break;
 377                                         default:
 378                                                 throw Error("unknown register " + reg);
 379                                 }
 380                         }
 381                 } else if (cmd == "add") {
 382                         ++i;
 383                         if (i == end) {
 384                                 throw Error("unexpected script end after add");
 385                         }
 386                         const string &reg((*i)->RegisterName());
 387                         if (reg.size() != 2) {
 388                                 throw Error("invalid register name " + reg);
 389                         }
 390                         ++i;
 391                         if (i == end) {
 392                                 throw Error("unexpected script end after add");
 393                         }
 394                         if ((*i)->GetType() != ScriptToken::REGISTER) {
 395                                 switch (reg[0]) {
 396                                         case 'i':
 397                                                 size += sizeof(int);
 398                                                 break;
 399                                         case 'v':
 400                                                 size += sizeof(Vector<int>);
 401                                                 break;
 402                                         default:
 403                                                 throw Error("expected register after add " + reg);
 404                                 }
 405                         }
 406                 } else if (cmd == "mod") {
 407                         ++i;
 408                         if (i == end) {
 409                                 throw Error("unexpected script end after mod");
 410                         }
 411                         ++i;
 412                         if (i == end) {
 413                                 throw Error("unexpected script end after mod");
 414                         }
 415                         if ((*i)->GetType() != ScriptToken::REGISTER) {
 416                                 size += sizeof(int);
 417                         }
 418                 } else if (cmd == "rand") {
 419                         ++i;
 420                         if (i == end) {
 421                                 throw Error("unexpected script end after rand");
 422                         }
 423                 } else if (cmd == "cmp") {
 424                         ++i;
 425                         if (i == end) {
 426                                 throw Error("unexpected script end after cmp");
 427                         }
 428                         if ((*i)->GetType() != ScriptToken::REGISTER) {
 429                                 size += sizeof(int);
 430                         }
 431                         ++i;
 432                         if (i == end) {
 433                                 throw Error("unexpected script end after cmp");
 434                         }
 435                         if ((*i)->GetType() != ScriptToken::REGISTER) {
 436                                 size += sizeof(int);
 437                         }
 438                 } else if (cmd == "jmp") {
 439                         size += sizeof(int);
 440                         ++i;
 441                         if (i == end) {
 442                                 throw Error("unexpected script end after cmp");
 443                         }
 444                 } else if (cmd == "jeq") {
 445                         size += sizeof(int);
 446                         ++i;
 447                         if (i == end) {
 448                                 throw Error("unexpected script end after cmp");
 449                         }
 450                 } else if (cmd == "jne") {
 451                         size += sizeof(int);
 452                         ++i;
 453                         if (i == end) {
 454                                 throw Error("unexpected script end after cmp");
 455                         }
 456                 } else if (cmd == "jl") {
 457                         size += sizeof(int);
 458                         ++i;
 459                         if (i == end) {
 460                                 throw Error("unexpected script end after cmp");
 461                         }
 462                 } else if (cmd == "jle") {
 463                         size += sizeof(int);
 464                         ++i;
 465                         if (i == end) {
 466                                 throw Error("unexpected script end after cmp");
 467                         }
 468                 } else if (cmd == "jg") {
 469                         size += sizeof(int);
 470                         ++i;
 471                         if (i == end) {
 472                                 throw Error("unexpected script end after cmp");
 473                         }
 474                 } else if (cmd == "jge") {
 475                         size += sizeof(int);
 476                         ++i;
 477                         if (i == end) {
 478                                 throw Error("unexpected script end after cmp");
 479                         }
 480                 } else if (cmd == "sysc") {
 481
 482                 } else {
 483                         throw Error("unknown command " + cmd);
 484                 }
 485         }
 486
 487         char *text(alloc.Alloc(size));
 488         int cursor(0);
 489         for (vector<ScriptToken *>::const_iterator i(s.begin()), end(s.end()); i != end; ++i) {
 490                 if ((*i)->GetType() == ScriptToken::LABEL) {
 491                         continue;
 492                 }
 493                 if ((*i)->GetType() != ScriptToken::COMMAND) {
 494                         throw Error("unexpected script token");
 495                 }
 496                 const string &cmd((*i)->CommandName());
 497                 if (cmd == "move") {
 498                         Script::Code &code(CreateScriptCode(Script::COMMAND_MOVE, text + cursor));
 499                         cursor += sizeof(Script::Code);
 500                         code.numParams = 2;
 501                         ++i;
 502                         const string &reg((*i)->RegisterName());
 503                         switch (reg[0]) {
 504                                 case 'a':
 505                                         code.type = Script::TYPE_ADDRESS;
 506                                         break;
 507                                 case 'i':
 508                                         code.type = Script::TYPE_INTEGER;
 509                                         break;
 510                                 case 'v':
 511                                         code.type = Script::TYPE_VECTOR;
 512                                         break;
 513                                 default:
 514                                         throw Error("invalid register " + reg);
 515                         }
 516                         int regnum(reg[1] - '0');
 517                         if (regnum < 0 || regnum > 6) {
 518                                 throw Error("invalid register " + reg);
 519                         }
 520                         code.reg1 = regnum;
 521                         ++i;
 522
 523                         if ((*i)->GetType() == ScriptToken::REGISTER) {
 524                                 string reg2((*i)->RegisterName());
 525                                 if (reg[0] != reg2[0]) {
 526                                         throw Error("mixed-type commands not allowed");
 527                                 }
 528                                 int reg2num(reg[1] - '0');
 529                                 if (reg2num < 0 || reg2num > 6) {
 530                                         throw Error("invalid register " + reg2);
 531                                 }
 532                                 code.reg2 = reg2num;
 533                         } else {
 534                                 code.reg2 = 7;
 535                                 switch (code.type) {
 536                                         case Script::TYPE_ADDRESS:
 537                                                 ReadScriptAddress(**i, text + cursor);
 538                                                 cursor += sizeof(void *);
 539                                                 break;
 540                                         case Script::TYPE_INTEGER:
 541                                                 ReadScriptInteger(**i, text + cursor);
 542                                                 cursor += sizeof(int);
 543                                                 break;
 544                                         case Script::TYPE_VECTOR:
 545                                                 ReadScriptVector(**i, text + cursor);
 546                                                 cursor += sizeof(Vector<int>);
 547                                                 break;
 548                                 }
 549                         }
 550                 } else if (cmd == "add") {
 551                         Script::Code &code(CreateScriptCode(Script::COMMAND_ADD, text + cursor));
 552                         cursor += sizeof(Script::Code);
 553                         code.numParams = 2;
 554                         ++i;
 555                         const string &reg((*i)->RegisterName());
 556                         switch (reg[0]) {
 557                                 case 'i':
 558                                         code.type = Script::TYPE_INTEGER;
 559                                         break;
 560                                 case 'v':
 561                                         code.type = Script::TYPE_VECTOR;
 562                                         break;
 563                                 default:
 564                                         throw Error("invalid register " + reg);
 565                         }
 566                         int regnum(reg[1] - '0');
 567                         if (regnum < 0 || regnum > 6) {
 568                                 throw Error("invalid register " + reg);
 569                         }
 570                         code.reg1 = regnum;
 571                         ++i;
 572
 573                         if ((*i)->GetType() == ScriptToken::REGISTER) {
 574                                 string reg2((*i)->RegisterName());
 575                                 if (reg[0] != reg2[0]) {
 576                                         throw Error("mixed-type commands not allowed");
 577                                 }
 578                                 int reg2num(reg[1] - '0');
 579                                 if (reg2num < 0 || reg2num > 6) {
 580                                         throw Error("invalid register name " + reg2);
 581                                 }
 582                                 code.reg2 = reg2num;
 583                         } else {
 584                                 code.reg2 = 7;
 585                                 switch (code.type) {
 586                                         case Script::TYPE_INTEGER:
 587                                                 ReadScriptInteger(**i, text + cursor);
 588                                                 cursor += sizeof(int);
 589                                                 break;
 590                                         case Script::TYPE_VECTOR:
 591                                                 ReadScriptVector(**i, text + cursor);
 592                                                 cursor += sizeof(Vector<int>);
 593                                                 break;
 594                                 }
 595                         }
 596                 } else if (cmd == "mod") {
 597                         Script::Code &code(CreateScriptCode(Script::COMMAND_MOD, text + cursor));
 598                         cursor += sizeof(Script::Code);
 599                         code.numParams = 2;
 600                         ++i;
 601                         const string &reg((*i)->RegisterName());
 602                         if (reg[0] != 'i') {
 603                                 throw Error("invalid register " + reg);
 604                         }
 605                         code.type = Script::TYPE_INTEGER;
 606                         int regnum(reg[1] - '0');
 607                         if (regnum < 0 || regnum > 6) {
 608                                 throw Error("invalid register " + reg);
 609                         }
 610                         code.reg1 = regnum;
 611                         ++i;
 612
 613                         if ((*i)->GetType() == ScriptToken::REGISTER) {
 614                                 string reg2((*i)->RegisterName());
 615                                 if (reg[0] != reg2[0]) {
 616                                         throw Error("mixed-type commands not allowed");
 617                                 }
 618                                 int reg2num(reg[1] - '0');
 619                                 if (reg2num < 0 || reg2num > 6) {
 620                                         throw Error("invalid register name " + reg2);
 621                                 }
 622                                 code.reg2 = reg2num;
 623                         } else {
 624                                 code.reg2 = 7;
 625                                 ReadScriptInteger(**i, text + cursor);
 626                                 cursor += sizeof(int);
 627                         }
 628                 } else if (cmd == "rand") {
 629                         Script::Code &code(CreateScriptCode(Script::COMMAND_RAND, text + cursor));
 630                         cursor += sizeof(Script::Code);
 631                         code.numParams = 1;
 632                         ++i;
 633                         const string &reg((*i)->RegisterName());
 634                         if (reg[0] != 'i') {
 635                                 throw Error("invalid register " + reg);
 636                         }
 637                         code.type = Script::TYPE_INTEGER;
 638                         int regnum(reg[1] - '0');
 639                         if (regnum < 0 || regnum > 6) {
 640                                 throw Error("invalid register " + reg);
 641                         }
 642                         code.reg1 = regnum;
 643                 } else if (cmd == "cmp") {
 644                         Script::Code &code(CreateScriptCode(Script::COMMAND_CMP, text + cursor));
 645                         cursor += sizeof(Script::Code);
 646                         code.numParams = 2;
 647                         ++i;
 648                         const string &reg((*i)->RegisterName());
 649                         if (reg[0] != 'i') {
 650                                 throw Error("invalid register " + reg);
 651                         }
 652                         code.type = Script::TYPE_INTEGER;
 653                         int regnum(reg[1] - '0');
 654                         if (regnum < 0 || regnum > 6) {
 655                                 throw Error("invalid register " + reg);
 656                         }
 657                         code.reg1 = regnum;
 658                         ++i;
 659
 660                         if ((*i)->GetType() == ScriptToken::REGISTER) {
 661                                 string reg2((*i)->RegisterName());
 662                                 if (reg[0] != reg2[0]) {
 663                                         throw Error("mixed-type commands not allowed");
 664                                 }
 665                                 int reg2num(reg[1] - '0');
 666                                 if (reg2num < 0 || reg2num > 6) {
 667                                         throw Error("invalid register name " + reg2);
 668                                 }
 669                                 code.reg2 = reg2num;
 670                         } else {
 671                                 code.reg2 = 7;
 672                                 ReadScriptInteger(**i, text + cursor);
 673                                 cursor += sizeof(int);
 674                         }
 675                 } else if (cmd == "jmp") {
 676                         Script::Code &code(CreateScriptCode(Script::COMMAND_JMP, text + cursor));
 677                         cursor += sizeof(Script::Code);
 678                         code.numParams = 1;
 679                         ++i;
 680                         if (!labels.count((*i)->Identifier())) {
 681                                 throw Error("use of undefined label " + (*i)->Identifier());
 682                         }
 683                         *reinterpret_cast<int *>(text + cursor) = labels[(*i)->Identifier()];
 684                         cursor += sizeof(int);
 685                 } else if (cmd == "jeq") {
 686                         Script::Code &code(CreateScriptCode(Script::COMMAND_JEQ, text + cursor));
 687                         cursor += sizeof(Script::Code);
 688                         code.numParams = 1;
 689                         ++i;
 690                         if (!labels.count((*i)->Identifier())) {
 691                                 throw Error("use of undefined label " + (*i)->Identifier());
 692                         }
 693                         *reinterpret_cast<int *>(text + cursor) = labels[(*i)->Identifier()];
 694                         cursor += sizeof(int);
 695                 } else if (cmd == "jne") {
 696                         Script::Code &code(CreateScriptCode(Script::COMMAND_JNE, text + cursor));
 697                         cursor += sizeof(Script::Code);
 698                         code.numParams = 1;
 699                         ++i;
 700                         if (!labels.count((*i)->Identifier())) {
 701                                 throw Error("use of undefined label " + (*i)->Identifier());
 702                         }
 703                         *reinterpret_cast<int *>(text + cursor) = labels[(*i)->Identifier()];
 704                         cursor += sizeof(int);
 705                 } else if (cmd == "jl") {
 706                         Script::Code &code(CreateScriptCode(Script::COMMAND_JL, text + cursor));
 707                         cursor += sizeof(Script::Code);
 708                         code.numParams = 1;
 709                         ++i;
 710                         if (!labels.count((*i)->Identifier())) {
 711                                 throw Error("use of undefined label " + (*i)->Identifier());
 712                         }
 713                         *reinterpret_cast<int *>(text + cursor) = labels[(*i)->Identifier()];
 714                         cursor += sizeof(int);
 715                 } else if (cmd == "jle") {
 716                         Script::Code &code(CreateScriptCode(Script::COMMAND_JLE, text + cursor));
 717                         cursor += sizeof(Script::Code);
 718                         code.numParams = 1;
 719                         ++i;
 720                         if (!labels.count((*i)->Identifier())) {
 721                                 throw Error("use of undefined label " + (*i)->Identifier());
 722                         }
 723                         *reinterpret_cast<int *>(text + cursor) = labels[(*i)->Identifier()];
 724                         cursor += sizeof(int);
 725                 } else if (cmd == "jg") {
 726                         Script::Code &code(CreateScriptCode(Script::COMMAND_JG, text + cursor));
 727                         cursor += sizeof(Script::Code);
 728                         code.numParams = 1;
 729                         ++i;
 730                         if (!labels.count((*i)->Identifier())) {
 731                                 throw Error("use of undefined label " + (*i)->Identifier());
 732                         }
 733                         *reinterpret_cast<int *>(text + cursor) = labels[(*i)->Identifier()];
 734                         cursor += sizeof(int);
 735                 } else if (cmd == "jge") {
 736                         Script::Code &code(CreateScriptCode(Script::COMMAND_JGE, text + cursor));
 737                         cursor += sizeof(Script::Code);
 738                         code.numParams = 1;
 739                         ++i;
 740                         if (!labels.count((*i)->Identifier())) {
 741                                 throw Error("use of undefined label " + (*i)->Identifier());
 742                         }
 743                         *reinterpret_cast<int *>(text + cursor) = labels[(*i)->Identifier()];
 744                         cursor += sizeof(int);
 745                 } else if (cmd == "sysc") {
 746                         Script::Code &code(CreateScriptCode(Script::COMMAND_SYSC, text + cursor));
 747                         cursor += sizeof(Script::Code);
 748                         code.numParams = 0;
 749                 } else {
 750                         throw Error("unknown command " + cmd);
 751                 }
 752         }
 753
 754         script->text = text;
 755         script->textlen = size;
 756 }
 757
 758 char *Interpreter::ReadScript(const vector<ScriptToken *> &s) {
 759         char *mem(alloc.Alloc(sizeof(Script)));
 760         new (mem) Script;
 761         Script *script(reinterpret_cast<Script *>(mem));
 762         ReadScript(s, script);
 763         return mem;
 764 }
 765
 766 Script::Code &Interpreter::CreateScriptCode(Script::Command c, char *dest) {
 767         Script::Code &code(*reinterpret_cast<Script::Code *>(dest));
 768         code.command = c;
 769         code.numParams = 0;
 770         code.type = Script::TYPE_NONE;
 771         code.reg1 = 7;
 772         code.reg2 = 7;
 773         return code;
 774 }
 775
 776 void Interpreter::ReadScriptAddress(const ScriptToken &t, char *dest) {
 777         if (t.GetType() != ScriptToken::IDENTIFIER) {
 778                 throw Error("expected identifier for address");
 779         }
 780         if (source.IsDefined(t.Identifier())) {
 781                 const ParsedDefinition &def(GetDefinition(t.Identifier()));
 782                 void *addr(GetObject(def.type, t.Identifier()));
 783                 *reinterpret_cast<void **>(dest) = addr;
 784         } else {
 785                 throw Error("postponing values in scripts not implemented");
 786         }
 787 }
 788
 789 void Interpreter::ReadScriptInteger(const ScriptToken &t, char *dest) {
 790         if (t.GetType() == ScriptToken::IDENTIFIER) {
 791                 if (source.IsDefined(t.Identifier())) {
 792                         void *num(GetObject(TypeDescription::GetTypeId("Number"), t.Identifier()));
 793                         *reinterpret_cast<int *>(dest) = *reinterpret_cast<int *>(num);
 794                 } else {
 795                         throw Error("postponing values in scripts not implemented");
 796                 }
 797         } else if (t.GetType() == ScriptToken::LITERAL) {
 798                 *reinterpret_cast<int *>(dest) = t.GetLiteral()->GetNumber();
 799         } else {
 800                 throw Error("expected identifier or integer literal");
 801         }
 802 }
 803
 804 void Interpreter::ReadScriptVector(const ScriptToken &t, char *dest) {
 805         if (t.GetType() == ScriptToken::IDENTIFIER) {
 806                 if (source.IsDefined(t.Identifier())) {
 807                         void *vec(GetObject(TypeDescription::GetTypeId("Vector"), t.Identifier()));
 808                         *reinterpret_cast<Vector<int> *>(dest) = *reinterpret_cast<Vector<int> *>(vec);
 809                 } else {
 810                         throw Error("postponing values in scripts not implemented");
 811                 }
 812         } else if (t.GetType() == ScriptToken::LITERAL) {
 813                 *reinterpret_cast<Vector<int> *>(dest) = Vector<int>(t.GetLiteral()->GetX(), t.GetLiteral()->GetY());
 814         } else {
 815                 throw Error("expected identifier or vector literal");
 816         }
 817 }
 818
 819
 820 SDL_Surface *Interpreter::GetImage(const string &path) {
 821         std::map<string, SDL_Surface *>::const_iterator result(imageCache.find(path));
 822         if (result != imageCache.end()) {
 823                 return result->second;
 824         } else {
 825                 SDL_Surface *image(IMG_Load(path.c_str()));
 826                 imageCache.insert(make_pair(path, image));
 827                 return image;
 828         }
 829 }
 830
 831
 832 bool Interpreter::CanLink(const Value &v) const {
 833         return v.IsLiteral() || source.IsDefined(v.GetIdentifier());
 834 }
 835
 836 void Interpreter::Postpone(int type, int id, std::ptrdiff_t offset, const std::string &identifier, int linkedType, bool inlined) {
 837         char *str(alloc.Alloc(identifier.size() + 1));
 838         std::memcpy(str, identifier.c_str(), identifier.size());
 839         str[identifier.size()] = '\0';
 840         postponedDefinitions.push_back(PostponedDefinition(type, id, offset, str, linkedType, inlined));
 841 }
 842
 843
 844 void Interpreter::CreateTypeDescriptions() {
 845         {
 846                 TypeDescription &td(TypeDescription::Create(BOOLEAN_ID, "Boolean"));
 847                 td.SetDescription("Logical value which can be either true or false.");
 848                 td.SetSize(sizeof(bool));
 849         }
 850         {
 851                 TypeDescription &td(TypeDescription::Create(COLOR_ID, "Color"));
 852                 td.SetDescription(
 853                                 "A color in RGB format with an optional alpha channel.\n"
 854                                 "Components range from 0 to 255.\n"
 855                                 "Alpha defaults to 255 if omitted.");
 856                 td.SetSize(sizeof(Color));
 857         }
 858         {
 859                 TypeDescription &td(TypeDescription::Create(IMAGE_ID, "Image"));
 860                 td.SetDescription("Path to a PNG file with image data.");
 861                 td.SetSize(sizeof(SDL_Surface));
 862         }
 863         {
 864                 TypeDescription &td(TypeDescription::Create(NUMBER_ID, "Number"));
 865                 td.SetDescription("A signed integer.");
 866                 td.SetSize(sizeof(int));
 867         }
 868         {;
 869                 TypeDescription &td(TypeDescription::Create(PATH_ID, "Path"));
 870                 td.SetDescription("A path in the filesystem which is interpreted relative to the source file's location.");
 871                 td.SetSize(1);
 872                 td.AddSupertype(STRING_ID, 0);
 873         }
 874         {
 875                 TypeDescription &td(TypeDescription::Create(SCRIPT_ID, "Script"));
 876                 td.SetDescription("Collection of commands that define a behaviour.");
 877                 td.SetSize(sizeof(Script));
 878         }
 879         {
 880                 TypeDescription &td(TypeDescription::Create(STRING_ID, "String"));
 881                 td.SetDescription("Some characters.");
 882                 td.SetSize(1);
 883         }
 884         {
 885                 TypeDescription &td(TypeDescription::Create(VECTOR_ID, "Vector"));
 886                 td.SetDescription("A pair of numbers usually describing a 2D translation or offset.");
 887                 td.SetSize(sizeof(Vector<int>));
 888         }
 889 }
 890
 891 }