#include "funct.hpp"
#include "syntree.hpp"

//Destruktor 
Funct::~Funct()
{
  delete _code;
}

// Registar funkcija
map<string, Funct*> Funct::_functions;

// Poziv funkcije za date vrednosti argumenata
int Funct::Call(const vector<int>& values)
{
  // Proveravamo korektnost broja argumenata
  if (values.size() != _args.size())
    throw "Wrong number of arguments in function call";
  
  // Formalnim argumentima dodeljujemo lokalne promenljive
  map<string, int> variables;
  for (size_t i = 0; i<values.size(); i++)
    variables[_args[i]] = values[i];
  
  // Vrsimo interpretaciju koda
  _code->Interpret(variables);
  
  // Rezultat se nalazi u promenljivoj sa imenom _result
  return variables[_result];
}

Function* Funct::Codegen() const
{
  Function *theFunction = theModule->getFunction(_name);
  if (theFunction != nullptr)
    throw "Nije dozvoljeno redefinisanje fje" + _name;

    
  vector<Type*> Ints(_args.size(), Type::getInt32Ty(theContext));
  FunctionType *FT;
  if (HasReturn())
    FT = FunctionType::get(Type::getInt32Ty(theContext), Ints, false);
  else
    FT = FunctionType::get(Type::getVoidTy(theContext), Ints, false);

  theFunction = Function::Create(FT, Function::ExternalLinkage, _name, theModule);

  unsigned idx = 0;
  for (auto &arg : theFunction->args())
    arg.setName(_args[idx++]);
  
  if (!theFunction)
    return nullptr;

  BasicBlock *BB = BasicBlock::Create(theContext, "entry", theFunction);
  builder.SetInsertPoint(BB);
  
  
  namedValues.clear();
  for (auto &arg : theFunction->args()) {
    AllocaInst* alloca = createEntryBlockAlloca(theFunction, arg.getName());
    builder.CreateStore(&arg, alloca);
    namedValues[arg.getName()] = alloca;
  }

  if (_code->Codegen()) {
    if (HasReturn()) {
      AllocaInst* alloca = namedValues[_result];
      if (alloca == nullptr)
	throw "Nije postavljen rezultat " + _result + " fje " + _name;
      Value *v = builder.CreateLoad(alloca, _result);
      builder.CreateRet(v);
    }
    else
      builder.CreateRetVoid();
    
    verifyFunction(*theFunction);
    
    theFPM->run(*theFunction);
    
    return theFunction;
  }

  theFunction->eraseFromParent();
  return nullptr;
}