// Copyright 2016 PDFium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com

#include "core/fxcrt/cfx_chariter.h"

#include "third_party/base/ptr_util.h"

CFX_CharIter::CFX_CharIter(const CFX_WideString& wsText)
    : m_wsText(wsText), m_nIndex(0) {
  ASSERT(!wsText.IsEmpty());
}

CFX_CharIter::~CFX_CharIter() {}

bool CFX_CharIter::Next(bool bPrev) {
  if (bPrev) {
    if (m_nIndex <= 0)
      return false;
    m_nIndex--;
  } else {
    if (static_cast<FX_STRSIZE>(m_nIndex + 1) >= m_wsText.GetLength())
      return false;
    m_nIndex++;
  }
  return true;
}

wchar_t CFX_CharIter::GetChar() const {
  return m_wsText[m_nIndex];
}

void CFX_CharIter::SetAt(int32_t nIndex) {
  if (nIndex < 0 || static_cast<FX_STRSIZE>(nIndex) >= m_wsText.GetLength())
    return;
  m_nIndex = nIndex;
}

int32_t CFX_CharIter::GetAt() const {
  return m_nIndex;
}

bool CFX_CharIter::IsEOF(bool bTail) const {
  return bTail ? (static_cast<FX_STRSIZE>(m_nIndex + 1) == m_wsText.GetLength())
               : (m_nIndex == 0);
}

std::unique_ptr<IFX_CharIter> CFX_CharIter::Clone() const {
  auto pIter = pdfium::MakeUnique<CFX_CharIter>(m_wsText);
  pIter->m_nIndex = m_nIndex;
  return pIter;
}