// 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_INCLUDE_FXCRT_FX_BASIC_H_
#define CORE_INCLUDE_FXCRT_FX_BASIC_H_

#include <algorithm>

#include "fx_memory.h"
#include "fx_stream.h"
#include "fx_string.h"
#include "fx_system.h"

// The FX_ArraySize(arr) macro returns the # of elements in an array arr.
// The expression is a compile-time constant, and therefore can be
// used in defining new arrays, for example.  If you use FX_ArraySize on
// a pointer by mistake, you will get a compile-time error.
//
// One caveat is that FX_ArraySize() doesn't accept any array of an
// anonymous type or a type defined inside a function.
#define FX_ArraySize(array) (sizeof(ArraySizeHelper(array)))

// This template function declaration is used in defining FX_ArraySize.
// Note that the function doesn't need an implementation, as we only
// use its type.
template <typename T, size_t N>
char(&ArraySizeHelper(T(&array)[N]))[N];

class CFX_BinaryBuf {
 public:
  CFX_BinaryBuf();
  CFX_BinaryBuf(FX_STRSIZE size);

  ~CFX_BinaryBuf();

  void Clear();

  void EstimateSize(FX_STRSIZE size, FX_STRSIZE alloc_step = 0);

  void AppendBlock(const void* pBuf, FX_STRSIZE size);

  void AppendFill(uint8_t byte, FX_STRSIZE count);

  void AppendString(const CFX_ByteStringC& str) {
    AppendBlock(str.GetPtr(), str.GetLength());
  }

  inline void AppendByte(uint8_t byte) {
    if (m_AllocSize <= m_DataSize) {
      ExpandBuf(1);
    }
    m_pBuffer[m_DataSize++] = byte;
  }

  void InsertBlock(FX_STRSIZE pos, const void* pBuf, FX_STRSIZE size);

  void AttachData(void* pBuf, FX_STRSIZE size);

  void CopyData(const void* pBuf, FX_STRSIZE size);

  void TakeOver(CFX_BinaryBuf& other);

  void Delete(int start_index, int count);

  uint8_t* GetBuffer() const { return m_pBuffer; }

  FX_STRSIZE GetSize() const { return m_DataSize; }

  CFX_ByteStringC GetByteString() const;

  void DetachBuffer();

 protected:
  FX_STRSIZE m_AllocStep;

  uint8_t* m_pBuffer;

  FX_STRSIZE m_DataSize;

  FX_STRSIZE m_AllocSize;

  void ExpandBuf(FX_STRSIZE size);
};
class CFX_ByteTextBuf : public CFX_BinaryBuf {
 public:
  void operator=(const CFX_ByteStringC& str);

  void AppendChar(int ch) { AppendByte((uint8_t)ch); }

  CFX_ByteTextBuf& operator<<(int i);

  CFX_ByteTextBuf& operator<<(FX_DWORD i);

  CFX_ByteTextBuf& operator<<(double f);

  CFX_ByteTextBuf& operator<<(const CFX_ByteStringC& lpsz);

  CFX_ByteTextBuf& operator<<(const CFX_ByteTextBuf& buf);

  FX_STRSIZE GetLength() const { return m_DataSize; }
};
class CFX_WideTextBuf : public CFX_BinaryBuf {
 public:
  void operator=(const FX_WCHAR* lpsz);

  void operator=(const CFX_WideStringC& str);

  void AppendChar(FX_WCHAR wch);

  CFX_WideTextBuf& operator<<(int i);

  CFX_WideTextBuf& operator<<(double f);

  CFX_WideTextBuf& operator<<(const FX_WCHAR* lpsz);

  CFX_WideTextBuf& operator<<(const CFX_WideStringC& str);
  CFX_WideTextBuf& operator<<(const CFX_WideString& str);

  CFX_WideTextBuf& operator<<(const CFX_WideTextBuf& buf);

  FX_STRSIZE GetLength() const { return m_DataSize / sizeof(FX_WCHAR); }

  FX_WCHAR* GetBuffer() const { return (FX_WCHAR*)m_pBuffer; }

  void Delete(int start_index, int count) {
    CFX_BinaryBuf::Delete(start_index * sizeof(FX_WCHAR),
                          count * sizeof(FX_WCHAR));
  }

  CFX_WideStringC GetWideString() const;
};

class IFX_BufferArchive {
 public:
  IFX_BufferArchive(FX_STRSIZE size);
  virtual ~IFX_BufferArchive() {}

  virtual void Clear();

  FX_BOOL Flush();

  int32_t AppendBlock(const void* pBuf, size_t size);

  int32_t AppendByte(uint8_t byte);

  int32_t AppendDWord(FX_DWORD i);

  int32_t AppendString(const CFX_ByteStringC& lpsz);

 protected:
  virtual FX_BOOL DoWork(const void* pBuf, size_t size) = 0;

  FX_STRSIZE m_BufSize;

  uint8_t* m_pBuffer;

  FX_STRSIZE m_Length;
};

class CFX_FileBufferArchive : public IFX_BufferArchive {
 public:
  CFX_FileBufferArchive(FX_STRSIZE size = 32768);
  ~CFX_FileBufferArchive() override;

  void Clear() override;
  FX_BOOL AttachFile(IFX_StreamWrite* pFile, FX_BOOL bTakeover = FALSE);

 private:
  FX_BOOL DoWork(const void* pBuf, size_t size) override;

  IFX_StreamWrite* m_pFile;
  FX_BOOL m_bTakeover;
};

struct CFX_CharMap {
  static CFX_CharMap* GetDefaultMapper(int32_t codepage = 0);

  CFX_WideString (*m_GetWideString)(CFX_CharMap* pMap,
                                    const CFX_ByteString& bstr);

  CFX_ByteString (*m_GetByteString)(CFX_CharMap* pMap,
                                    const CFX_WideString& wstr);

  int32_t (*m_GetCodePage)();
};
class CFX_UTF8Decoder {
 public:
  CFX_UTF8Decoder() { m_PendingBytes = 0; }

  void Clear();

  void Input(uint8_t byte);

  void AppendChar(FX_DWORD ch);

  void ClearStatus() { m_PendingBytes = 0; }

  CFX_WideStringC GetResult() const { return m_Buffer.GetWideString(); }

 protected:
  int m_PendingBytes;

  FX_DWORD m_PendingChar;

  CFX_WideTextBuf m_Buffer;
};

class CFX_UTF8Encoder {
 public:
  CFX_UTF8Encoder() {}

  void Input(FX_WCHAR unicode);
  void AppendStr(const CFX_ByteStringC& str) { m_Buffer << str; }
  CFX_ByteStringC GetResult() const { return m_Buffer.GetByteString(); }

 protected:
  CFX_ByteTextBuf m_Buffer;
};

class CFX_BasicArray {
 protected:
  CFX_BasicArray(int unit_size);

  ~CFX_BasicArray();

  FX_BOOL SetSize(int nNewSize);

  FX_BOOL Append(const CFX_BasicArray& src);

  FX_BOOL Copy(const CFX_BasicArray& src);

  uint8_t* InsertSpaceAt(int nIndex, int nCount);

  FX_BOOL RemoveAt(int nIndex, int nCount);

  FX_BOOL InsertAt(int nStartIndex, const CFX_BasicArray* pNewArray);

  const void* GetDataPtr(int index) const;

 protected:
  uint8_t* m_pData;

  int m_nSize;

  int m_nMaxSize;

  int m_nUnitSize;
};
template <class TYPE>
class CFX_ArrayTemplate : public CFX_BasicArray {
 public:
  CFX_ArrayTemplate() : CFX_BasicArray(sizeof(TYPE)) {}

  int GetSize() const { return m_nSize; }

  int GetUpperBound() const { return m_nSize - 1; }

  FX_BOOL SetSize(int nNewSize) { return CFX_BasicArray::SetSize(nNewSize); }

  void RemoveAll() { SetSize(0); }

  const TYPE GetAt(int nIndex) const {
    if (nIndex < 0 || nIndex >= m_nSize) {
      return (const TYPE&)(*(volatile const TYPE*)NULL);
    }
    return ((const TYPE*)m_pData)[nIndex];
  }

  FX_BOOL SetAt(int nIndex, TYPE newElement) {
    if (nIndex < 0 || nIndex >= m_nSize) {
      return FALSE;
    }
    ((TYPE*)m_pData)[nIndex] = newElement;
    return TRUE;
  }

  TYPE& ElementAt(int nIndex) {
    if (nIndex < 0 || nIndex >= m_nSize) {
      return *(TYPE*)NULL;
    }
    return ((TYPE*)m_pData)[nIndex];
  }

  const TYPE* GetData() const { return (const TYPE*)m_pData; }

  TYPE* GetData() { return (TYPE*)m_pData; }

  FX_BOOL SetAtGrow(int nIndex, TYPE newElement) {
    if (nIndex < 0) {
      return FALSE;
    }
    if (nIndex >= m_nSize)
      if (!SetSize(nIndex + 1)) {
        return FALSE;
      }
    ((TYPE*)m_pData)[nIndex] = newElement;
    return TRUE;
  }

  FX_BOOL Add(TYPE newElement) {
    if (m_nSize < m_nMaxSize) {
      m_nSize++;
    } else if (!SetSize(m_nSize + 1)) {
      return FALSE;
    }
    ((TYPE*)m_pData)[m_nSize - 1] = newElement;
    return TRUE;
  }

  FX_BOOL Append(const CFX_ArrayTemplate& src) {
    return CFX_BasicArray::Append(src);
  }

  FX_BOOL Copy(const CFX_ArrayTemplate& src) {
    return CFX_BasicArray::Copy(src);
  }

  TYPE* GetDataPtr(int index) {
    return (TYPE*)CFX_BasicArray::GetDataPtr(index);
  }

  TYPE* AddSpace() { return (TYPE*)CFX_BasicArray::InsertSpaceAt(m_nSize, 1); }

  TYPE* InsertSpaceAt(int nIndex, int nCount) {
    return (TYPE*)CFX_BasicArray::InsertSpaceAt(nIndex, nCount);
  }

  const TYPE operator[](int nIndex) const {
    if (nIndex < 0 || nIndex >= m_nSize) {
      *(volatile char*)0 = '\0';
    }
    return ((const TYPE*)m_pData)[nIndex];
  }

  TYPE& operator[](int nIndex) {
    if (nIndex < 0 || nIndex >= m_nSize) {
      *(volatile char*)0 = '\0';
    }
    return ((TYPE*)m_pData)[nIndex];
  }

  FX_BOOL InsertAt(int nIndex, TYPE newElement, int nCount = 1) {
    if (!InsertSpaceAt(nIndex, nCount)) {
      return FALSE;
    }
    while (nCount--) {
      ((TYPE*)m_pData)[nIndex++] = newElement;
    }
    return TRUE;
  }

  FX_BOOL RemoveAt(int nIndex, int nCount = 1) {
    return CFX_BasicArray::RemoveAt(nIndex, nCount);
  }

  FX_BOOL InsertAt(int nStartIndex, const CFX_BasicArray* pNewArray) {
    return CFX_BasicArray::InsertAt(nStartIndex, pNewArray);
  }

  int Find(TYPE data, int iStart = 0) const {
    if (iStart < 0) {
      return -1;
    }
    for (; iStart < (int)m_nSize; iStart++)
      if (((TYPE*)m_pData)[iStart] == data) {
        return iStart;
      }
    return -1;
  }
};
typedef CFX_ArrayTemplate<uint8_t> CFX_ByteArray;
typedef CFX_ArrayTemplate<FX_WORD> CFX_WordArray;
typedef CFX_ArrayTemplate<FX_DWORD> CFX_DWordArray;
typedef CFX_ArrayTemplate<void*> CFX_PtrArray;
typedef CFX_ArrayTemplate<FX_FILESIZE> CFX_FileSizeArray;

template <class ObjectClass>
class CFX_ObjectArray : public CFX_BasicArray {
 public:
  CFX_ObjectArray() : CFX_BasicArray(sizeof(ObjectClass)) {}

  ~CFX_ObjectArray() { RemoveAll(); }

  void Add(const ObjectClass& data) {
    new ((void*)InsertSpaceAt(m_nSize, 1)) ObjectClass(data);
  }

  ObjectClass& Add() {
    return *(ObjectClass*)new ((void*)InsertSpaceAt(m_nSize, 1)) ObjectClass();
  }

  void* AddSpace() { return InsertSpaceAt(m_nSize, 1); }

  int32_t Append(const CFX_ObjectArray& src,
                 int32_t nStart = 0,
                 int32_t nCount = -1) {
    if (nCount == 0) {
      return 0;
    }
    int32_t nSize = src.GetSize();
    if (!nSize) {
      return 0;
    }
    FXSYS_assert(nStart > -1 && nStart < nSize);
    if (nCount < 0) {
      nCount = nSize;
    }
    if (nStart + nCount > nSize) {
      nCount = nSize - nStart;
    }
    if (nCount < 1) {
      return 0;
    }
    nSize = m_nSize;
    InsertSpaceAt(m_nSize, nCount);
    ObjectClass* pStartObj = (ObjectClass*)GetDataPtr(nSize);
    nSize = nStart + nCount;
    for (int32_t i = nStart; i < nSize; i++, pStartObj++) {
      new ((void*)pStartObj) ObjectClass(src[i]);
    }
    return nCount;
  }

  int32_t Copy(const CFX_ObjectArray& src,
               int32_t nStart = 0,
               int32_t nCount = -1) {
    if (nCount == 0) {
      return 0;
    }
    int32_t nSize = src.GetSize();
    if (!nSize) {
      return 0;
    }
    FXSYS_assert(nStart > -1 && nStart < nSize);
    if (nCount < 0) {
      nCount = nSize;
    }
    if (nStart + nCount > nSize) {
      nCount = nSize - nStart;
    }
    if (nCount < 1) {
      return 0;
    }
    RemoveAll();
    SetSize(nCount);
    ObjectClass* pStartObj = (ObjectClass*)m_pData;
    nSize = nStart + nCount;
    for (int32_t i = nStart; i < nSize; i++, pStartObj++) {
      new ((void*)pStartObj) ObjectClass(src[i]);
    }
    return nCount;
  }

  int GetSize() const { return m_nSize; }

  ObjectClass& operator[](int index) const {
    FXSYS_assert(index < m_nSize);
    return *(ObjectClass*)CFX_BasicArray::GetDataPtr(index);
  }

  ObjectClass* GetDataPtr(int index) {
    return (ObjectClass*)CFX_BasicArray::GetDataPtr(index);
  }

  void RemoveAt(int index) {
    FXSYS_assert(index < m_nSize);
    ((ObjectClass*)GetDataPtr(index))->~ObjectClass();
    CFX_BasicArray::RemoveAt(index, 1);
  }

  void RemoveAll() {
    for (int i = 0; i < m_nSize; i++) {
      ((ObjectClass*)GetDataPtr(i))->~ObjectClass();
    }
    CFX_BasicArray::SetSize(0);
  }
};
typedef CFX_ObjectArray<CFX_ByteString> CFX_ByteStringArray;
typedef CFX_ObjectArray<CFX_WideString> CFX_WideStringArray;
template <class DataType, int FixedSize>
class CFX_FixedBufGrow {
 public:
  CFX_FixedBufGrow() : m_pData(NULL) {}
  CFX_FixedBufGrow(int data_size) : m_pData(NULL) {
    if (data_size > FixedSize) {
      m_pData = FX_Alloc(DataType, data_size);
    } else {
      FXSYS_memset(m_Data, 0, sizeof(DataType) * FixedSize);
    }
  }
  void SetDataSize(int data_size) {
    FX_Free(m_pData);
    m_pData = NULL;
    if (data_size > FixedSize) {
      m_pData = FX_Alloc(DataType, data_size);
    } else {
      FXSYS_memset(m_Data, 0, sizeof(DataType) * FixedSize);
    }
  }
  ~CFX_FixedBufGrow() { FX_Free(m_pData); }
  operator DataType*() { return m_pData ? m_pData : m_Data; }

 private:
  DataType m_Data[FixedSize];
  DataType* m_pData;
};

class CFX_PtrList {
 protected:
  struct CNode {
    CNode* pNext;

    CNode* pPrev;

    void* data;
  };

 public:
  CFX_PtrList(int nBlockSize = 10);

  FX_POSITION GetHeadPosition() const { return (FX_POSITION)m_pNodeHead; }

  FX_POSITION GetTailPosition() const { return (FX_POSITION)m_pNodeTail; }

  void* GetNext(FX_POSITION& rPosition) const {
    CNode* pNode = (CNode*)rPosition;
    rPosition = (FX_POSITION)pNode->pNext;
    return pNode->data;
  }

  void* GetPrev(FX_POSITION& rPosition) const {
    CNode* pNode = (CNode*)rPosition;
    rPosition = (FX_POSITION)pNode->pPrev;
    return pNode->data;
  }

  FX_POSITION GetNextPosition(FX_POSITION pos) const {
    return ((CNode*)pos)->pNext;
  }

  FX_POSITION GetPrevPosition(FX_POSITION pos) const {
    return ((CNode*)pos)->pPrev;
  }

  void* GetAt(FX_POSITION rPosition) const {
    CNode* pNode = (CNode*)rPosition;
    return pNode->data;
  }

  int GetCount() const { return m_nCount; }

  FX_POSITION AddTail(void* newElement);

  FX_POSITION AddHead(void* newElement);

  void SetAt(FX_POSITION pos, void* newElement) {
    CNode* pNode = (CNode*)pos;
    pNode->data = newElement;
  }

  FX_POSITION InsertAfter(FX_POSITION pos, void* newElement);

  FX_POSITION Find(void* searchValue, FX_POSITION startAfter = NULL) const;

  FX_POSITION FindIndex(int index) const;

  void RemoveAt(FX_POSITION pos);

  void RemoveAll();

 protected:
  CNode* m_pNodeHead;

  CNode* m_pNodeTail;

  int m_nCount;

  CNode* m_pNodeFree;

  struct CFX_Plex* m_pBlocks;

  int m_nBlockSize;

  CNode* NewNode(CNode* pPrev, CNode* pNext);

  void FreeNode(CNode* pNode);

 public:
  ~CFX_PtrList();
};
typedef void (*PD_CALLBACK_FREEDATA)(void* pData);
struct FX_PRIVATEDATA {
  void FreeData();

  void* m_pModuleId;

  void* m_pData;

  PD_CALLBACK_FREEDATA m_pCallback;

  FX_BOOL m_bSelfDestruct;
};
class CFX_PrivateData {
 public:
  ~CFX_PrivateData();

  void ClearAll();

  void SetPrivateData(void* module_id,
                      void* pData,
                      PD_CALLBACK_FREEDATA callback);

  void SetPrivateObj(void* module_id, CFX_DestructObject* pObj);

  void* GetPrivateData(void* module_id);

  FX_BOOL LookupPrivateData(void* module_id, void*& pData) const {
    if (!module_id) {
      return FALSE;
    }
    FX_DWORD nCount = m_DataList.GetSize();
    for (FX_DWORD n = 0; n < nCount; n++) {
      if (m_DataList[n].m_pModuleId == module_id) {
        pData = m_DataList[n].m_pData;
        return TRUE;
      }
    }
    return FALSE;
  }

  FX_BOOL RemovePrivateData(void* module_id);

 protected:
  CFX_ArrayTemplate<FX_PRIVATEDATA> m_DataList;

  void AddData(void* module_id,
               void* pData,
               PD_CALLBACK_FREEDATA callback,
               FX_BOOL bSelfDestruct);
};
class CFX_BitStream {
 public:
  void Init(const uint8_t* pData, FX_DWORD dwSize);

  FX_DWORD GetBits(FX_DWORD nBits);

  void ByteAlign();

  FX_BOOL IsEOF() { return m_BitPos >= m_BitSize; }

  void SkipBits(FX_DWORD nBits) { m_BitPos += nBits; }

  void Rewind() { m_BitPos = 0; }

  FX_DWORD GetPos() const { return m_BitPos; }

  FX_DWORD BitsRemaining() const {
    return m_BitSize >= m_BitPos ? m_BitSize - m_BitPos : 0;
  }

 protected:
  FX_DWORD m_BitPos;

  FX_DWORD m_BitSize;

  const uint8_t* m_pData;
};
template <class ObjClass>
class CFX_CountRef {
 public:
  typedef CFX_CountRef<ObjClass> Ref;

  class CountedObj : public ObjClass {
   public:
    CountedObj() {}

    CountedObj(const CountedObj& src) : ObjClass(src) {}

    int m_RefCount;
  };

  CFX_CountRef() { m_pObject = NULL; }

  CFX_CountRef(const Ref& ref) {
    m_pObject = ref.m_pObject;
    if (m_pObject) {
      m_pObject->m_RefCount++;
    }
  }

  ~CFX_CountRef() {
    if (!m_pObject) {
      return;
    }
    m_pObject->m_RefCount--;
    if (m_pObject->m_RefCount <= 0) {
      delete m_pObject;
    }
  }

  ObjClass* New() {
    if (m_pObject) {
      m_pObject->m_RefCount--;
      if (m_pObject->m_RefCount <= 0) {
        delete m_pObject;
      }
    }
    m_pObject = new CountedObj;
    m_pObject->m_RefCount = 1;
    return m_pObject;
  }

  void operator=(const Ref& ref) {
    if (ref.m_pObject) {
      ref.m_pObject->m_RefCount++;
    }
    if (m_pObject) {
      m_pObject->m_RefCount--;
      if (m_pObject->m_RefCount <= 0) {
        delete m_pObject;
      }
    }
    m_pObject = ref.m_pObject;
  }

  void operator=(void* p) {
    FXSYS_assert(p == 0);
    if (!m_pObject) {
      return;
    }
    m_pObject->m_RefCount--;
    if (m_pObject->m_RefCount <= 0) {
      delete m_pObject;
    }
    m_pObject = NULL;
  }

  const ObjClass* GetObject() const { return m_pObject; }

  operator const ObjClass*() const { return m_pObject; }

  FX_BOOL IsNull() const { return !m_pObject; }

  FX_BOOL NotNull() const { return !IsNull(); }

  ObjClass* GetModify() {
    if (!m_pObject) {
      m_pObject = new CountedObj;
      m_pObject->m_RefCount = 1;
    } else if (m_pObject->m_RefCount > 1) {
      m_pObject->m_RefCount--;
      CountedObj* pOldObject = m_pObject;
      m_pObject = new CountedObj(*pOldObject);
      m_pObject->m_RefCount = 1;
    }
    return m_pObject;
  }

  void SetNull() {
    if (!m_pObject) {
      return;
    }
    m_pObject->m_RefCount--;
    if (m_pObject->m_RefCount <= 0) {
      delete m_pObject;
    }
    m_pObject = NULL;
  }

  FX_BOOL operator==(const Ref& ref) const {
    return m_pObject == ref.m_pObject;
  }

 protected:
  CountedObj* m_pObject;
};
class IFX_Pause {
 public:
  virtual ~IFX_Pause() {}
  virtual FX_BOOL NeedToPauseNow() = 0;
};

template <typename T>
class CFX_AutoRestorer {
 public:
  explicit CFX_AutoRestorer(T* location)
      : m_Location(location), m_OldValue(*location) {}
  ~CFX_AutoRestorer() { *m_Location = m_OldValue; }

 private:
  T* const m_Location;
  const T m_OldValue;
};

struct FxFreeDeleter {
  inline void operator()(void* ptr) const { FX_Free(ptr); }
};

// Used with std::unique_ptr to Release() objects that can't be deleted.
template <class T>
struct ReleaseDeleter {
  inline void operator()(T* ptr) const { ptr->Release(); }
};

#define FX_DATALIST_LENGTH 1024
template <size_t unit>
class CFX_SortListArray {
 protected:
  struct DataList {
    int32_t start;

    int32_t count;
    uint8_t* data;
  };

 public:
  CFX_SortListArray() : m_CurList(0) {}

  ~CFX_SortListArray() { Clear(); }

  void Clear() {
    for (int32_t i = m_DataLists.GetUpperBound(); i >= 0; i--) {
      DataList list = m_DataLists.ElementAt(i);
      FX_Free(list.data);
    }
    m_DataLists.RemoveAll();
    m_CurList = 0;
  }

  void Append(int32_t nStart, int32_t nCount) {
    if (nStart < 0) {
      return;
    }
    while (nCount > 0) {
      int32_t temp_count = std::min(nCount, FX_DATALIST_LENGTH);
      DataList list;
      list.data = FX_Alloc2D(uint8_t, temp_count, unit);
      list.start = nStart;
      list.count = temp_count;
      Append(list);
      nCount -= temp_count;
      nStart += temp_count;
    }
  }

  uint8_t* GetAt(int32_t nIndex) {
    if (nIndex < 0) {
      return NULL;
    }
    if (m_CurList < 0 || m_CurList >= m_DataLists.GetSize()) {
      return NULL;
    }
    DataList* pCurList = m_DataLists.GetDataPtr(m_CurList);
    if (!pCurList || nIndex < pCurList->start ||
        nIndex >= pCurList->start + pCurList->count) {
      pCurList = NULL;
      int32_t iStart = 0;
      int32_t iEnd = m_DataLists.GetUpperBound();
      int32_t iMid = 0;
      while (iStart <= iEnd) {
        iMid = (iStart + iEnd) / 2;
        DataList* list = m_DataLists.GetDataPtr(iMid);
        if (nIndex < list->start) {
          iEnd = iMid - 1;
        } else if (nIndex >= list->start + list->count) {
          iStart = iMid + 1;
        } else {
          pCurList = list;
          m_CurList = iMid;
          break;
        }
      }
    }
    return pCurList ? pCurList->data + (nIndex - pCurList->start) * unit : NULL;
  }

 protected:
  void Append(const DataList& list) {
    int32_t iStart = 0;
    int32_t iEnd = m_DataLists.GetUpperBound();
    int32_t iFind = 0;
    while (iStart <= iEnd) {
      int32_t iMid = (iStart + iEnd) / 2;
      DataList* cur_list = m_DataLists.GetDataPtr(iMid);
      if (list.start < cur_list->start + cur_list->count) {
        iEnd = iMid - 1;
      } else {
        if (iMid == iEnd) {
          iFind = iMid + 1;
          break;
        }
        DataList* next_list = m_DataLists.GetDataPtr(iMid + 1);
        if (list.start < next_list->start) {
          iFind = iMid + 1;
          break;
        } else {
          iStart = iMid + 1;
        }
      }
    }
    m_DataLists.InsertAt(iFind, list);
  }
  int32_t m_CurList;
  CFX_ArrayTemplate<DataList> m_DataLists;
};
template <typename T1, typename T2>
class CFX_ListArrayTemplate {
 public:
  void Clear() { m_Data.Clear(); }

  void Add(int32_t nStart, int32_t nCount) { m_Data.Append(nStart, nCount); }

  T2& operator[](int32_t nIndex) {
    uint8_t* data = m_Data.GetAt(nIndex);
    FXSYS_assert(data);
    return (T2&)(*(volatile T2*)data);
  }

  T2* GetPtrAt(int32_t nIndex) { return (T2*)m_Data.GetAt(nIndex); }

 protected:
  T1 m_Data;
};
typedef CFX_ListArrayTemplate<CFX_SortListArray<sizeof(FX_FILESIZE)>,
                              FX_FILESIZE> CFX_FileSizeListArray;

class CFX_Vector_3by1 {
 public:
  CFX_Vector_3by1() : a(0.0f), b(0.0f), c(0.0f) {}

  CFX_Vector_3by1(FX_FLOAT a1, FX_FLOAT b1, FX_FLOAT c1)
      : a(a1), b(b1), c(c1) {}

  FX_FLOAT a;
  FX_FLOAT b;
  FX_FLOAT c;
};
class CFX_Matrix_3by3 {
 public:
  CFX_Matrix_3by3()
      : a(0.0f),
        b(0.0f),
        c(0.0f),
        d(0.0f),
        e(0.0f),
        f(0.0f),
        g(0.0f),
        h(0.0f),
        i(0.0f) {}

  CFX_Matrix_3by3(FX_FLOAT a1,
                  FX_FLOAT b1,
                  FX_FLOAT c1,
                  FX_FLOAT d1,
                  FX_FLOAT e1,
                  FX_FLOAT f1,
                  FX_FLOAT g1,
                  FX_FLOAT h1,
                  FX_FLOAT i1)
      : a(a1), b(b1), c(c1), d(d1), e(e1), f(f1), g(g1), h(h1), i(i1) {}

  CFX_Matrix_3by3 Inverse();

  CFX_Matrix_3by3 Multiply(const CFX_Matrix_3by3& m);

  CFX_Vector_3by1 TransformVector(const CFX_Vector_3by1& v);

  FX_FLOAT a;
  FX_FLOAT b;
  FX_FLOAT c;
  FX_FLOAT d;
  FX_FLOAT e;
  FX_FLOAT f;
  FX_FLOAT g;
  FX_FLOAT h;
  FX_FLOAT i;
};

#endif  // CORE_INCLUDE_FXCRT_FX_BASIC_H_