// Copyright 2014 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 <list>

#include "core/fxcodec/codec/codec_int.h"
#include "core/fxcodec/include/fx_codec.h"

namespace {

class CCodec_Jbig2Context {
 public:
  CCodec_Jbig2Context();
  ~CCodec_Jbig2Context() {}

  uint32_t m_width;
  uint32_t m_height;
  CPDF_StreamAcc* m_pGlobalStream;
  CPDF_StreamAcc* m_pSrcStream;
  uint8_t* m_dest_buf;
  uint32_t m_dest_pitch;
  IFX_Pause* m_pPause;
  CJBig2_Context* m_pContext;
  CJBig2_Image* m_dest_image;
};

}  // namespace

// Holds per-document JBig2 related data.
class JBig2DocumentContext : public CFX_Deletable {
 public:
  std::list<CJBig2_CachePair>* GetSymbolDictCache() {
    return &m_SymbolDictCache;
  }

  ~JBig2DocumentContext() override {
    for (auto it : m_SymbolDictCache) {
      delete it.second;
    }
  }

 private:
  std::list<CJBig2_CachePair> m_SymbolDictCache;
};

JBig2DocumentContext* GetJBig2DocumentContext(
    std::unique_ptr<CFX_Deletable>* pContextHolder) {
  if (!pContextHolder->get())
    pContextHolder->reset(new JBig2DocumentContext());
  return static_cast<JBig2DocumentContext*>(pContextHolder->get());
}

CCodec_Jbig2Context::CCodec_Jbig2Context() {
  FXSYS_memset(this, 0, sizeof(CCodec_Jbig2Context));
}

CCodec_Jbig2Module::~CCodec_Jbig2Module() {}

void* CCodec_Jbig2Module::CreateJbig2Context() {
  return new CCodec_Jbig2Context();
}
void CCodec_Jbig2Module::DestroyJbig2Context(void* pJbig2Content) {
  if (pJbig2Content) {
    CJBig2_Context::DestroyContext(
        ((CCodec_Jbig2Context*)pJbig2Content)->m_pContext);
    delete (CCodec_Jbig2Context*)pJbig2Content;
  }
  pJbig2Content = nullptr;
}
FXCODEC_STATUS CCodec_Jbig2Module::StartDecode(
    void* pJbig2Context,
    std::unique_ptr<CFX_Deletable>* pContextHolder,
    uint32_t width,
    uint32_t height,
    CPDF_StreamAcc* src_stream,
    CPDF_StreamAcc* global_stream,
    uint8_t* dest_buf,
    uint32_t dest_pitch,
    IFX_Pause* pPause) {
  if (!pJbig2Context) {
    return FXCODEC_STATUS_ERR_PARAMS;
  }
  JBig2DocumentContext* pJBig2DocumentContext =
      GetJBig2DocumentContext(pContextHolder);
  CCodec_Jbig2Context* m_pJbig2Context = (CCodec_Jbig2Context*)pJbig2Context;
  m_pJbig2Context->m_width = width;
  m_pJbig2Context->m_height = height;
  m_pJbig2Context->m_pSrcStream = src_stream;
  m_pJbig2Context->m_pGlobalStream = global_stream;
  m_pJbig2Context->m_dest_buf = dest_buf;
  m_pJbig2Context->m_dest_pitch = dest_pitch;
  m_pJbig2Context->m_pPause = pPause;
  FXSYS_memset(dest_buf, 0, height * dest_pitch);
  m_pJbig2Context->m_pContext = CJBig2_Context::CreateContext(
      global_stream, src_stream, pJBig2DocumentContext->GetSymbolDictCache(),
      pPause);
  if (!m_pJbig2Context->m_pContext) {
    return FXCODEC_STATUS_ERROR;
  }
  int ret = m_pJbig2Context->m_pContext->getFirstPage(dest_buf, width, height,
                                                      dest_pitch, pPause);
  if (m_pJbig2Context->m_pContext->GetProcessingStatus() ==
      FXCODEC_STATUS_DECODE_FINISH) {
    CJBig2_Context::DestroyContext(m_pJbig2Context->m_pContext);
    m_pJbig2Context->m_pContext = nullptr;
    if (ret != JBIG2_SUCCESS) {
      return FXCODEC_STATUS_ERROR;
    }
    int dword_size = height * dest_pitch / 4;
    uint32_t* dword_buf = (uint32_t*)dest_buf;
    for (int i = 0; i < dword_size; i++) {
      dword_buf[i] = ~dword_buf[i];
    }
    return FXCODEC_STATUS_DECODE_FINISH;
  }
  return m_pJbig2Context->m_pContext->GetProcessingStatus();
}
FXCODEC_STATUS CCodec_Jbig2Module::ContinueDecode(void* pJbig2Context,
                                                  IFX_Pause* pPause) {
  CCodec_Jbig2Context* m_pJbig2Context = (CCodec_Jbig2Context*)pJbig2Context;
  int ret = m_pJbig2Context->m_pContext->Continue(pPause);
  if (m_pJbig2Context->m_pContext->GetProcessingStatus() !=
      FXCODEC_STATUS_DECODE_FINISH) {
    return m_pJbig2Context->m_pContext->GetProcessingStatus();
  }
  CJBig2_Context::DestroyContext(m_pJbig2Context->m_pContext);
  m_pJbig2Context->m_pContext = nullptr;
  if (ret != JBIG2_SUCCESS) {
    return FXCODEC_STATUS_ERROR;
  }
  int dword_size =
      m_pJbig2Context->m_height * m_pJbig2Context->m_dest_pitch / 4;
  uint32_t* dword_buf = (uint32_t*)m_pJbig2Context->m_dest_buf;
  for (int i = 0; i < dword_size; i++) {
    dword_buf[i] = ~dword_buf[i];
  }
  return FXCODEC_STATUS_DECODE_FINISH;
}