/* -*- mode: objc; coding: utf-8 -*- */

#import "libobjcl.h"
#import "libffi_support.h"
#import "objc_support.h"

#import <Foundation/Foundation.h>
#include <stdarg.h>
#include <objc/objc-api.h>

#ifdef __NEXT_RUNTIME__
#include <objc/objc-class.h>
#endif


static NSAutoreleasePool *objcl_autorelease_pool = NULL;

/* Preallocate an exception to throw when memory is all used up. */
NSException *objcl_oom_exception;


void
objcl_initialise_runtime (void)
{
  objcl_autorelease_pool = [[NSAutoreleasePool alloc] init];
  objcl_oom_exception = [NSException exceptionWithName: @"MLKOutOfMemoryException"
                                     reason: @"Out of memory"
                                     userInfo: nil];
}


void
objcl_shutdown_runtime (void)
{
  [objcl_autorelease_pool release];
}


#ifdef USE_LIBFFI
id
objcl_invoke_with_types (int argc,
                         char *return_typespec,
                         char *arg_typespecs[],
                         void *return_value,
                         void **argv)
{
  IMP method;
  int i;
  ffi_cif cif;
  ffi_type *return_type;
  ffi_type *arg_types[argc + 2];
  ffi_status status;

  id receiver = *((id*)argv[0]);
  SEL method_selector = *((SEL*)argv[1]);

  static ffi_type *id_type = NULL;
  static ffi_type *sel_type = NULL;

  if (!id_type)
    id_type = objcl_pyobjc_arg_signature_to_ffi_type ("@");
  if (!sel_type)
    sel_type = objcl_pyobjc_arg_signature_to_ffi_type (":");

  NS_DURING
    {
#ifdef __NEXT_RUNTIME__
      method = class_getInstanceMethod ([receiver class], method_selector)->method_imp;
#else
      method = objc_msg_lookup (receiver, method_selector);
      /* Alternatively:
         method = [receiver methodForSelector: method_selector];
      */
#endif

      if (method == NULL)
        [[NSException exceptionWithName: @"MLKNoApplicableMethod"
                      reason: @"Tried to call a non-existent method."
                      userInfo: nil] raise];

      return_type = objcl_pyobjc_signature_to_ffi_return_type (return_typespec);
      arg_types[0] = id_type;
      arg_types[1] = sel_type;

      for (i = 0; i < argc; i++)
        arg_types[i + 2] = objcl_pyobjc_arg_signature_to_ffi_type (arg_typespecs[i]);

      status = ffi_prep_cif (&cif, FFI_DEFAULT_ABI, argc + 2, return_type, arg_types);
      if (status != FFI_OK)
        {
          [[NSException exceptionWithName: @"MLKInvalidFFITypeException"
                        reason: @"FFI type is invalid (this is probably a bug)."
                        userInfo: nil] raise];
        }

      ffi_call (&cif, FFI_FN (method), return_value, argv);
    }
  NS_HANDLER
    {
      NS_VALUERETURN (localException, id);
    }
  NS_ENDHANDLER

  return NULL;
}
#endif


Class
objcl_find_class (const char *class_name)
{
  return NSClassFromString ([NSString stringWithUTF8String: class_name]);
}


SEL
objcl_find_selector (const char *class_name)
{
  return NSSelectorFromString ([NSString stringWithUTF8String: class_name]);
}


const char *
objcl_class_name (Class class)
{
  const char *ns_name;
  char *name;

  ns_name = [(NSStringFromClass (class)) UTF8String];
  name = malloc (strlen (ns_name) + 1);
  strcpy (name, ns_name);

  return name;
}


const char *
objcl_selector_name (SEL selector)
{
  const char *ns_name;
  char *name;

  ns_name = [(NSStringFromSelector (selector)) UTF8String];
  name = malloc (strlen (ns_name) + 1);
  strcpy (name, ns_name);

  return name;
}


IMP
objcl_get_method_implementation (id object,
                                 SEL selector)
{
#ifdef __NEXT_RUNTIME__
  if (objcl_object_is_class (object))
    {
      return class_getClassMethod (object, selector)->method_imp;
    }
  else
    {
      return class_getInstanceMethod ([object class], selector)->method_imp;
    }
#else
  return objc_msg_lookup (object, selector);
#endif
}


BOOL
objcl_object_is_class (id obj)
{
#ifdef __NEXT_RUNTIME__
  return [obj class] == obj;
#else
  /* return CLS_ISCLASS (obj); */
  return object_is_class (obj);
#endif
}


BOOL
objcl_object_is_meta_class (id obj)
{
#ifdef __NEXT_RUNTIME__
  /* FIXME: What to do here? */
  return objcl_object_get_meta_class (obj) == obj;
#else
  /* return CLS_ISMETA (ptr); */
  if (objcl_object_is_class (obj))
    return class_is_meta_class (obj);
  else
    return object_is_meta_class (obj);
#endif
}


Class
objcl_object_get_class (id obj)
{
#ifdef __NEXT_RUNTIME__
  /* XXX? return obj->isa; */
  return [obj class];
#else
  return object_get_class (obj);
#endif
}


Class
objcl_object_get_meta_class (id obj)
{
#ifdef __NEXT_RUNTIME__
  /* FIXME: What to do here? */
  return objc_getMetaClass ([(NSStringFromClass ([obj class])) UTF8String]);
#else
  if (objcl_object_is_class (obj))
    return class_get_meta_class (obj);
  else
    return object_get_meta_class (obj);
#endif
}


id
objcl_get_nil (void)
{
  return nil;
}


long
objcl_get_yes ()
{
  if (sizeof (YES) > sizeof (long))
    fprintf (stderr, "WARNING: objcl_get_yes: YES might not fit into a long.\n");
  return YES;
}


long
objcl_get_no ()
{
  if (sizeof (NO) > sizeof (long))
    fprintf (stderr, "WARNING: objcl_get_no: NO might not fit into a long.\n");
  return NO;
}