edi = Ziron_ExtractLine(....

//move through tokens etc

mov
  eax,
  ecx

MyFunc(
  a, b, c
  d, e, f
);

mov

  eax,

plugin will take the control from the beginning , of course that will be after program statement , as you have said using event handler for 'program' term will be impossible.   

plugin will parse the source code here , by this sequence
   1- get the line , if it has a ';' then we have a valid line that ziron can execute it,
      else still get the next line and keep searching for ';' trem.
   2- start parse this line and see if we need to modify it then go ahead else pass it
      without changed to Ziron ,EG executes it.
   3- if we get the needed line we can modify it as desired and parse it then we can 
      make new line and execute it.
   4- loop this procedure until we found end of code       

int bufSize;
char* strSource;

procedure emitLine(char* line) {
  if (strAppend(strSource, line, bufSize) = false) {
    //we need to re-alloc strSource and extend buffer size
    edx = strSource;
    add bufSize, 2048
    strSource = new bufSize;    
    strlcpy(strSource, edx, 2048);
    delete edx; //delete old mem
    
    //now append it, maybe should check line is not 2048 bytes long :-p
    strAppend(strSource, line, bufSize);
  }
}

function InitPlugin(pointer pGetF) {
  Ziron_LoadAll(pGetF); //use framework utility function to load all

  //init strSource here
  bufSize = 2048;
  strSource = new 2048;

  return strLoaded;
}

function UnloadPlugin() {
  //free strSource here
  delete strSource;
}

function FileEntry(DWord handle; char* code) {
  uses edi;
  m_strFill(strSource, 1, 0); //set first character as null so we can re-use for strAppend
  
  //your usual code here
  char tmp[2048];
 
  edi = strGetLine(code, @tmp);
  while(edi <> 0) {
    Ziron_ShowMessage(@tmp);
    
    emitLine(@tmp);
    edi = strGetLine(edi, @tmp);
  }  
  
  Ziron_SetFileBuffer(handle, strSource, strLen(strSource));
}

entry function DLLMain(DWord iDLL; DWord iReason; Pointer iResult) {
  if (iReason == DLL_PROCESS_ATTACH) {
    return true;
  }

  return false;
}



exports InitPlugin, UnloadPlugin, FileEntry;