/* 7z.h -- 7z interface
2017-04-03 : Igor Pavlov : Public domain */

#ifndef __7Z_H
#define __7Z_H

#include "7zTypes.h"

EXTERN_C_BEGIN

#define k7zStartHeaderSize 0x20
#define k7zSignatureSize 6

extern const Byte k7zSignature[k7zSignatureSize];

typedef struct
{
  const Byte *Data;
  size_t Size;
} CSzData;

/* CSzCoderInfo & CSzFolder support only default methods */

typedef struct
{
  size_t PropsOffset;
  uint32_t MethodID;
  Byte NumStreams;
  Byte PropsSize;
} CSzCoderInfo;

typedef struct
{
  uint32_t InIndex;
  uint32_t OutIndex;
} CSzBond;

#define SZ_NUM_CODERS_IN_FOLDER_MAX 4
#define SZ_NUM_BONDS_IN_FOLDER_MAX 3
#define SZ_NUM_PACK_STREAMS_IN_FOLDER_MAX 4

typedef struct
{
  uint32_t NumCoders;
  uint32_t NumBonds;
  uint32_t NumPackStreams;
  uint32_t UnpackStream;
  uint32_t PackStreams[SZ_NUM_PACK_STREAMS_IN_FOLDER_MAX];
  CSzBond Bonds[SZ_NUM_BONDS_IN_FOLDER_MAX];
  CSzCoderInfo Coders[SZ_NUM_CODERS_IN_FOLDER_MAX];
} CSzFolder;


SRes SzGetNextFolderItem(CSzFolder *f, CSzData *sd);

typedef struct
{
  uint32_t Low;
  uint32_t High;
} CNtfsFileTime;

typedef struct
{
  Byte *Defs; /* MSB 0 bit numbering */
  uint32_t *Vals;
} CSzBitUi32s;

typedef struct
{
  Byte *Defs; /* MSB 0 bit numbering */
  /* uint64_t *Vals; */
  CNtfsFileTime *Vals;
} CSzBitUi64s;

#define SzBitArray_Check(p, i) (((p)[(i) >> 3] & (0x80 >> ((i) & 7))) != 0)

#define SzBitWithVals_Check(p, i) ((p)->Defs && ((p)->Defs[(i) >> 3] & (0x80 >> ((i) & 7))) != 0)

typedef struct
{
  uint32_t NumPackStreams;
  uint32_t NumFolders;

  uint64_t *PackPositions;          /* NumPackStreams + 1 */
  CSzBitUi32s FolderCRCs;         /* NumFolders */

  size_t *FoCodersOffsets;        /* NumFolders + 1 */
  uint32_t *FoStartPackStreamIndex; /* NumFolders + 1 */
  uint32_t *FoToCoderUnpackSizes;   /* NumFolders + 1 */
  Byte *FoToMainUnpackSizeIndex;  /* NumFolders */
  uint64_t *CoderUnpackSizes;       /* for all coders in all folders */

  Byte *CodersData;
} CSzAr;

uint64_t SzAr_GetFolderUnpackSize(const CSzAr *p, uint32_t folderIndex);

SRes SzAr_DecodeFolder(const CSzAr *p, uint32_t folderIndex,
    ILookInStream *stream, uint64_t startPos,
    Byte *outBuffer, size_t outSize,
    ISzAllocPtr allocMain);

typedef struct
{
  CSzAr db;

  uint64_t startPosAfterHeader;
  uint64_t dataPos;
  
  uint32_t NumFiles;

  uint64_t *UnpackPositions;  /* NumFiles + 1 */
  /* Byte *IsEmptyFiles; */
  Byte *IsDirs;
  CSzBitUi32s CRCs;

  CSzBitUi32s Attribs;
  /* CSzBitUi32s Parents; */
  CSzBitUi64s MTime;
  CSzBitUi64s CTime;

  uint32_t *FolderToFile;   /* NumFolders + 1 */
  uint32_t *FileToFolder;   /* NumFiles */

  size_t *FileNameOffsets; /* in 2-byte steps */
  Byte *FileNames;  /* UTF-16-LE */
} CSzArEx;

#define SzArEx_IsDir(p, i) (SzBitArray_Check((p)->IsDirs, i))

#define SzArEx_GetFileSize(p, i) ((p)->UnpackPositions[(i) + 1] - (p)->UnpackPositions[i])

void SzArEx_Init(CSzArEx *p);
void SzArEx_Free(CSzArEx *p, ISzAllocPtr alloc);
uint64_t SzArEx_GetFolderStreamPos(const CSzArEx *p, uint32_t folderIndex, uint32_t indexInFolder);
int SzArEx_GetFolderFullPackSize(const CSzArEx *p, uint32_t folderIndex, uint64_t *resSize);

/*
if dest == NULL, the return value specifies the required size of the buffer,
  in 16-bit characters, including the null-terminating character.
if dest != NULL, the return value specifies the number of 16-bit characters that
  are written to the dest, including the null-terminating character. */

size_t SzArEx_GetFileNameUtf16(const CSzArEx *p, size_t fileIndex, uint16_t *dest);

/*
size_t SzArEx_GetFullNameLen(const CSzArEx *p, size_t fileIndex);
uint16_t *SzArEx_GetFullNameUtf16_Back(const CSzArEx *p, size_t fileIndex, uint16_t *dest);
*/



/*
  SzArEx_Extract extracts file from archive

  *outBuffer must be 0 before first call for each new archive.

  Extracting cache:
    If you need to decompress more than one file, you can send
    these values from previous call:
      *blockIndex,
      *outBuffer,
      *outBufferSize
    You can consider "*outBuffer" as cache of solid block. If your archive is solid,
    it will increase decompression speed.
  
    If you use external function, you can declare these 3 cache variables
    (blockIndex, outBuffer, outBufferSize) as static in that external function.
    
    Free *outBuffer and set *outBuffer to 0, if you want to flush cache.
*/

SRes SzArEx_Extract(
    const CSzArEx *db,
    ILookInStream *inStream,
    uint32_t fileIndex,         /* index of file */
    uint32_t *blockIndex,       /* index of solid block */
    Byte **outBuffer,         /* pointer to pointer to output buffer (allocated with allocMain) */
    size_t *outBufferSize,    /* buffer size for output buffer */
    size_t *offset,           /* offset of stream for required file in *outBuffer */
    size_t *outSizeProcessed, /* size of file in *outBuffer */
    ISzAllocPtr allocMain,
    ISzAllocPtr allocTemp);


/*
SzArEx_Open Errors:
SZ_ERROR_NO_ARCHIVE
SZ_ERROR_ARCHIVE
SZ_ERROR_UNSUPPORTED
SZ_ERROR_MEM
SZ_ERROR_CRC
SZ_ERROR_INPUT_EOF
SZ_ERROR_FAIL
*/

SRes SzArEx_Open(CSzArEx *p, ILookInStream *inStream,
    ISzAllocPtr allocMain, ISzAllocPtr allocTemp);

EXTERN_C_END

#endif