/*
 * Copyright (c) 1999-2004 Sourceforge JACOB Project.
 * All rights reserved. Originator: Dan Adler (http://danadler.com).
 * Get more information about JACOB at http://sourceforge.net/projects/jacob-project
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
#include "stdafx.h"
#include <objbase.h>
#include "Dispatch.h"
// Win32 support for Ole Automation
#include <wchar.h>
#include <string.h>
#include <atlbase.h>
#include <oleauto.h>
#include <olectl.h>
#include "util.h"

/**
 * An implementation of IEnumVariant based on code submitted by
 * Thomas Hallgren (mailto:Thomas.Hallgren@eoncompany.com)
 */
extern "C"
{

// extract a IDispatch from a jobject
IEnumVARIANT* extractEnumVariant(JNIEnv* env, jobject arg)
{
  jfieldID FID_pIEnumVARIANT = 0;
  jclass clazz = env->GetObjectClass(arg);
  FID_pIEnumVARIANT = env->GetFieldID(clazz, "m_pIEnumVARIANT", "I");
  return (IEnumVARIANT*)env->GetIntField(arg, FID_pIEnumVARIANT);
}

JNIEXPORT jint JNICALL
Java_com_jacob_com_EnumVariant_Next(JNIEnv* env, jobject _this, jobjectArray vars)
{
  IEnumVARIANT* self = extractEnumVariant(env, _this);
	//printf("self=%x\n", self);
  if(self == NULL)
    return 0;

  ULONG count = (ULONG)env->GetArrayLength(vars);
  if(count == 0)
    return 0;

  VARIANT* sink = (VARIANT*)CoTaskMemAlloc(count * sizeof(VARIANT));
  ULONG fetchCount = 0;

  HRESULT hr = self->Next(count, sink, &fetchCount);
  if(FAILED(hr))
  {
    CoTaskMemFree(sink);
    ThrowComFail(env, "IEnumVARIANT::Next", hr);
    return 0;
  }

  // prepare a new return value array
  //
  jclass    clazz = env->FindClass("com/jacob/com/Variant");
  jmethodID ctor  = env->GetMethodID(clazz, "<init>", "()V");

  for(ULONG idx = 0; idx < fetchCount; ++idx)
  {
    // construct a variant to return
    //
    jobject newVariant = env->NewObject(clazz, ctor);
    VARIANT* v = extractVariant(env, newVariant);
    VariantCopy(v, sink + idx);
    env->SetObjectArrayElement(vars, idx, newVariant);
    env->DeleteLocalRef(newVariant);
    //Sourceforge-1674179 fix memory leak
    // Variants received while iterating IEnumVARIANT must be cleared when no longer needed
    // The variant has been copied so no longer needed
    VariantClear(sink);
  }
  CoTaskMemFree(sink);
  return (jint)fetchCount;
}

JNIEXPORT void JNICALL
Java_com_jacob_com_EnumVariant_release(JNIEnv* env, jobject _this)
{
  IEnumVARIANT* self = extractEnumVariant(env, _this);
  if(self != NULL)
  {
    self->Release();
    jfieldID FID_pIEnumVARIANT = 0;
    jclass clazz = env->GetObjectClass(_this);
    FID_pIEnumVARIANT = env->GetFieldID(clazz, "m_pIEnumVARIANT", "I");
    env->SetIntField(_this, FID_pIEnumVARIANT, (unsigned int)0);
  }
}

JNIEXPORT void JNICALL
Java_com_jacob_com_EnumVariant_Reset(JNIEnv* env, jobject _this)
{
  IEnumVARIANT* self = extractEnumVariant(env, _this);
  if(self == NULL)
    return;

  HRESULT hr = self->Reset();
  if(FAILED(hr))
    ThrowComFail(env, "IEnumVARIANT::Reset", hr);
}

JNIEXPORT void JNICALL
Java_com_jacob_com_EnumVariant_Skip(JNIEnv* env, jobject _this, jint count)
{
  IEnumVARIANT* self = extractEnumVariant(env, _this);
  if(self == NULL)
    return;

  HRESULT hr = self->Skip((ULONG)count);
  if(FAILED(hr))
    ThrowComFail(env, "IEnumVARIANT::Skip", hr);
}

}