#include "py4yap.h"
#include <VFS.h>

atom_t ATOM_true, ATOM_false, ATOM_colon, ATOM_dot, ATOM_none, ATOM_t,
  ATOM_comma, ATOM_builtin, ATOM_A, ATOM_V, ATOM_self, ATOM_nil, ATOM_brackets, ATOM_curly_brackets;

functor_t FUNCTOR_dollar1, FUNCTOR_abs1, FUNCTOR_all1, FUNCTOR_any1,
  FUNCTOR_bin1, FUNCTOR_brackets1, FUNCTOR_comma2, FUNCTOR_dir1,
  FUNCTOR_float1, FUNCTOR_int1, FUNCTOR_iter1, FUNCTOR_iter2, FUNCTOR_long1,
  FUNCTOR_len1, FUNCTOR_curly1, FUNCTOR_ord1, FUNCTOR_range1, FUNCTOR_range2,
  FUNCTOR_range3, FUNCTOR_sum1, FUNCTOR_pointer1, FUNCTOR_complex2,
  FUNCTOR_plus2, FUNCTOR_sub2, FUNCTOR_mul2, FUNCTOR_div2, FUNCTOR_hat2,
  FUNCTOR_colon2, FUNCTOR_comma2, FUNCTOR_equal2, FUNCTOR_sqbrackets2,
  FUNCTOR_dot2, FUNCTOR_brackets1;

X_API PyObject *py_Builtin;
X_API PyObject *py_Yapex;
X_API PyObject *py_Sys;
PyObject *py_Context;
PyObject *py_ModDict;

VFS_t pystream;

static void *
py_open( const char *name, const char *io_mode) {
#if HAVE_STRCASESTR
  if (strcasestr(name,"//python/")== name)
    name += strlen("//python/");
  #else
  if (strstr(name,"//python/")== name)
    name += strlen("//python/");
#endif
  // we assume object is already open, so there is no need to open it.
  PyObject *stream = string_to_python( name, true, NULL);
  if (stream == Py_None)
    return NULL;
  return stream;
}
		
static bool
py_close(int sno) {
  PyObject *s = YAP_foreign_stream(sno);
  PyObject* fclose = PyObject_GetAttrString(s, "close");
  PyObject* rc= PyObject_CallObject(fclose, NULL);
  bool v = (rc == Py_True);
  return v;
}

static PyObject *  pyw; // buffer
static int pyw_kind;
PyObject *  pyw_data;

static int
py_put(int sno, int ch) {
  PyObject *s = YAP_foreign_stream(sno);
  PyUnicode_WRITE( pyw_kind, pyw_data, 0, ch );
  PyObject* fput = PyObject_GetAttrString(s, "write");
  PyObject_CallFunctionObjArgs(fput, pyw, NULL);
  return ch;
}

static int
py_get(int sno) {
  PyObject *s = YAP_foreign_stream(sno);
  PyObject* fget = PyObject_GetAttrString(s, "read");
  PyObject *pyr = PyObject_CallFunctionObjArgs(fget, PyLong_FromLong(1), NULL);
  return  PyUnicode_READ_CHAR( pyr, 0) ;
}

static int64_t  py_seek(int sno, int64_t where, int how) {
  PyObject *s = YAP_foreign_stream(sno);
  PyObject* fseek = PyObject_GetAttrString(s, "seek");
  PyObject *pyr = PyObject_CallFunctionObjArgs(fseek, PyLong_FromLong(where), PyLong_FromLong(how), NULL);
  return PyLong_AsLong(pyr);
}

static void
py_flush(int sno) {
  PyObject *s = YAP_foreign_stream(sno);
  PyObject* flush = PyObject_GetAttrString(s, "flush");
  PyObject_CallFunction( flush, NULL);
}


		
static bool
init_python_stream(void)
{
  pyw = PyUnicode_FromString("x");
  pyw_kind = PyUnicode_KIND(pyw);
  pyw_data = PyUnicode_DATA(pyw);
  
  pystream.name = "python stream";
  pystream.vflags = VFS_CAN_WRITE|VFS_CAN_EXEC| VFS_CAN_SEEK|VFS_HAS_PREFIX;
  pystream.prefix = "//python/";
  pystream.suffix = NULL;
  pystream.open = py_open;
  pystream.close = py_close;
  pystream.get_char = py_get;
  pystream.put_char = py_put;
  pystream.flush = py_flush;
  pystream.seek = py_seek;
  pystream.next = GLOBAL_VFS;
  GLOBAL_VFS = &pystream;
  // NULL;
  return true;
}

X_API PyObject *py_F2P;

extern X_API bool python_in_python;

static void add_modules(void) {
  py_Main = PyImport_AddModule("__main__");
  Py_INCREF(py_Main);
  py_Sys = PyImport_AddModule("sys");
  Py_INCREF(py_Sys);
  py_Builtin = PyImport_AddModule("__builtin__");
  Py_INCREF(py_Builtin);
  py_ModDict = PyObject_GetAttrString(py_Sys, "modules");
  // py_Yapex = PyImport_ImportModule("yap4py.yapi");
  // PyObject *py_Yap =
  py_Yapex = PyImport_AddModule("yap4py.yapi");
  if (py_Yapex)
    Py_INCREF(py_Yapex);
  //py_F2P = PyObject_GetAttrString(py_Yap, "globals");
  py_F2P = NULL;
  init_python_stream();
}


static void install_py_constants(void) {
  FUNCTOR_dot2 = PL_new_functor(PL_new_atom("."), 2);
  // FUNCTOR_equal2 = PL_new_functor(PL_new_atom("="), 2);
  // FUNCTOR_boolop1 = PL_new_functor(PL_new_atom("@"), 1);
  ATOM_A = PL_new_atom("A");
  ATOM_V = PL_new_atom("V");
  ATOM_builtin = PL_new_atom("__builtin__");
  ATOM_comma = PL_new_atom(",");
  ATOM_colon = PL_new_atom(":");
  ATOM_true = PL_new_atom("true");
  ATOM_false = PL_new_atom("false");
  ATOM_dot = PL_new_atom(".");
  ATOM_self = PL_new_atom("self");
  ATOM_nil = PL_new_atom("[]");
  ATOM_brackets = PL_new_atom("()");
  ATOM_curly_brackets = PL_new_atom("{}");
  FUNCTOR_abs1 = PL_new_functor(PL_new_atom("abs"), 1);
  FUNCTOR_all1 = PL_new_functor(PL_new_atom("all"), 1);
  FUNCTOR_any1 = PL_new_functor(PL_new_atom("any"), 1);
  FUNCTOR_bin1 = PL_new_functor(PL_new_atom("bin"), 1);
  FUNCTOR_ord1 = PL_new_functor(PL_new_atom("ord"), 1);
  FUNCTOR_int1 = PL_new_functor(PL_new_atom("int"), 1);
  FUNCTOR_long1 = PL_new_functor(PL_new_atom("long"), 1);
  FUNCTOR_float1 = PL_new_functor(PL_new_atom("float"), 1);
  FUNCTOR_curly1 = PL_new_functor(PL_new_atom("{}"), 1);
  FUNCTOR_brackets1 = PL_new_functor(PL_new_atom("()"), 1);
  FUNCTOR_dollar1 = PL_new_functor(PL_new_atom("$"), 1);
  FUNCTOR_pointer1 = PL_new_functor(PL_new_atom("__obj__"), 1);
  FUNCTOR_dir1 = PL_new_functor(PL_new_atom("dir"), 1);
  FUNCTOR_iter1 = PL_new_functor(PL_new_atom("iter"), 1);
  FUNCTOR_iter2 = PL_new_functor(PL_new_atom("iter"), 2);
  FUNCTOR_len1 = PL_new_functor(PL_new_atom("len"), 1);
  FUNCTOR_range1 = PL_new_functor(PL_new_atom("range"), 1);
  FUNCTOR_range2 = PL_new_functor(PL_new_atom("range"), 2);
  FUNCTOR_range3 = PL_new_functor(PL_new_atom("range"), 3);
  FUNCTOR_sum1 = PL_new_functor(PL_new_atom("sum"), 1);
  FUNCTOR_complex2 = PL_new_functor(PL_new_atom("i"), 2);
  FUNCTOR_plus2 = PL_new_functor(PL_new_atom("+"), 2);
  FUNCTOR_sub2 = PL_new_functor(PL_new_atom("-"), 2);
  FUNCTOR_mul2 = PL_new_functor(PL_new_atom("*"), 2);
  FUNCTOR_div2 = PL_new_functor(PL_new_atom("/"), 2);
  FUNCTOR_hat2 = PL_new_functor(PL_new_atom("^"), 2);
  FUNCTOR_colon2 = PL_new_functor(PL_new_atom(":"), 2);
  FUNCTOR_comma2 = PL_new_functor(PL_new_atom(","), 2);
  FUNCTOR_equal2 = PL_new_functor(PL_new_atom("="), 2);
  FUNCTOR_sqbrackets2 = PL_new_functor(PL_new_atom("[]"), 2);
 }

foreign_t end_python(void) {
  if (!python_in_python)
    Py_Finalize();

  return true;
}

static bool libpython_initialized = 0;

X_API bool do_init_python(void) {
  //  char **argv;
 if (libpython_initialized)
    return true;
  libpython_initialized = true;

   //  PyGILState_STATE gstate = PyGILState_Ensure();
  term_t t = PL_new_term_ref();
  if (!python_in_python)
    Py_Initialize();
  install_py_constants();
  PL_reset_term_refs(t);
  install_pl2pl();
  // PyGILState_Release(gstate);
    add_modules();
  return true;

}

#ifndef _WIN32


O_API bool init_python_dll(void);


O_API bool init_python_dll(void) {
  do_init_python();
    install_pypreds();
    return 1;
}

#endif