// 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

#ifndef CORE_FXCODEC_JBIG2_JBIG2_CONTEXT_H_
#define CORE_FXCODEC_JBIG2_JBIG2_CONTEXT_H_

#include <list>
#include <memory>
#include <utility>
#include <vector>

#include "core/fxcodec/fx_codec_def.h"
#include "core/fxcodec/jbig2/JBig2_Page.h"
#include "core/fxcodec/jbig2/JBig2_Segment.h"
#include "core/fxcrt/fx_safe_types.h"
#include "third_party/base/span.h"

class CJBig2_ArithDecoder;
class CJBig2_GRDProc;
class CPDF_StreamAcc;
class PauseIndicatorIface;

// Cache is keyed by the ObjNum of a stream and an index within the stream.
using CJBig2_CacheKey = std::pair<uint32_t, uint32_t>;
using CJBig2_CachePair =
    std::pair<CJBig2_CacheKey, std::unique_ptr<CJBig2_SymbolDict>>;

#define JBIG2_MIN_SEGMENT_SIZE 11

enum class JBig2_Result { kSuccess, kFailure, kEndReached };

class CJBig2_Context {
 public:
  static std::unique_ptr<CJBig2_Context> Create(
      pdfium::span<const uint8_t> pGlobalSpan,
      uint32_t dwGlobalObjNum,
      pdfium::span<const uint8_t> pSrcSpan,
      uint32_t dwSrcObjNum,
      std::list<CJBig2_CachePair>* pSymbolDictCache);

  ~CJBig2_Context();

  static bool HuffmanAssignCode(JBig2HuffmanCode* SBSYMCODES, uint32_t NTEMP);

  bool GetFirstPage(uint8_t* pBuf,
                    int32_t width,
                    int32_t height,
                    int32_t stride,
                    PauseIndicatorIface* pPause);

  bool Continue(PauseIndicatorIface* pPause);
  FXCODEC_STATUS GetProcessingStatus() const { return m_ProcessingStatus; }

 private:
  CJBig2_Context(pdfium::span<const uint8_t> pSrcSpan,
                 uint32_t dwObjNum,
                 std::list<CJBig2_CachePair>* pSymbolDictCache,
                 bool bIsGlobal);

  JBig2_Result DecodeSequential(PauseIndicatorIface* pPause);

  CJBig2_Segment* FindSegmentByNumber(uint32_t dwNumber);
  CJBig2_Segment* FindReferredTableSegmentByIndex(CJBig2_Segment* pSegment,
                                                  int32_t nIndex);

  JBig2_Result ParseSegmentHeader(CJBig2_Segment* pSegment);
  JBig2_Result ParseSegmentData(CJBig2_Segment* pSegment,
                                PauseIndicatorIface* pPause);
  JBig2_Result ProcessingParseSegmentData(CJBig2_Segment* pSegment,
                                          PauseIndicatorIface* pPause);
  JBig2_Result ParseSymbolDict(CJBig2_Segment* pSegment);
  JBig2_Result ParseTextRegion(CJBig2_Segment* pSegment);
  JBig2_Result ParsePatternDict(CJBig2_Segment* pSegment,
                                PauseIndicatorIface* pPause);
  JBig2_Result ParseHalftoneRegion(CJBig2_Segment* pSegment,
                                   PauseIndicatorIface* pPause);
  JBig2_Result ParseGenericRegion(CJBig2_Segment* pSegment,
                                  PauseIndicatorIface* pPause);
  JBig2_Result ParseGenericRefinementRegion(CJBig2_Segment* pSegment);
  JBig2_Result ParseTable(CJBig2_Segment* pSegment);
  JBig2_Result ParseRegionInfo(JBig2RegionInfo* pRI);

  std::vector<JBig2HuffmanCode> DecodeSymbolIDHuffmanTable(uint32_t SBNUMSYMS);
  const CJBig2_HuffmanTable* GetHuffmanTable(size_t idx);

  std::unique_ptr<CJBig2_Context> m_pGlobalContext;
  std::unique_ptr<CJBig2_BitStream> m_pStream;
  std::vector<std::unique_ptr<CJBig2_Segment>> m_SegmentList;
  std::vector<std::unique_ptr<JBig2PageInfo>> m_PageInfoList;
  std::unique_ptr<CJBig2_Image> m_pPage;
  std::vector<std::unique_ptr<CJBig2_HuffmanTable>> m_HuffmanTables;
  const bool m_bIsGlobal;
  bool m_bInPage = false;
  bool m_bBufSpecified = false;
  int32_t m_PauseStep = 10;
  FXCODEC_STATUS m_ProcessingStatus = FXCODEC_STATUS_FRAME_READY;
  std::vector<JBig2ArithCtx> m_gbContext;
  std::unique_ptr<CJBig2_ArithDecoder> m_pArithDecoder;
  std::unique_ptr<CJBig2_GRDProc> m_pGRD;
  std::unique_ptr<CJBig2_Segment> m_pSegment;
  FX_SAFE_UINT32 m_dwOffset = 0;
  JBig2RegionInfo m_ri;
  std::list<CJBig2_CachePair>* const m_pSymbolDictCache;
};

#endif  // CORE_FXCODEC_JBIG2_JBIG2_CONTEXT_H_