/*---------------------------------------------------------------------------*
  Project:  NintendoWare
  File:     lyt_Arc.cpp
  
  Copyright (C)2009-2011 Nintendo/HAL Laboratory, Inc.  All rights reserved.
  
  These coded instructions, statements, and computer programs contain proprietary
  information of Nintendo and/or its licensed developers and are protected by
  national and international copyright laws. They may not be disclosed to third
  parties or copied or duplicated in any form, in whole or in part, without the
  prior written consent of Nintendo.
  
  The content herein is highly confidential and should be handled accordingly.
  
  $Revision: 31311 $
 *---------------------------------------------------------------------------*/

#include "precompiled.h"

#include <nw/lyt/lyt_Arc.h>
#include <ctype.h>          // for tolower

namespace nw
{
namespace lyt
{

typedef struct FSTEntry FSTEntry;

struct FSTEntry
{
    unsigned int    isDirAndStringOff;    // the first byte is for isDir
                                          // the next 3bytes: name offset
    unsigned int    parentOrPosition;     // parent entry (dir entry)
                                          // position (file entry)
    unsigned int    nextEntryOrLength;    // next entry (dir entry)
                                          // length (file entry)
};

#define entryIsDir(fstStart, i)     \
    ( ( ( fstStart[i].isDirAndStringOff & 0xff000000 ) == 0 )? false:true )
#define stringOff(fstStart, i)      \
        ( fstStart[i].isDirAndStringOff & 0x00ffffff )
#define parentDir(fstStart, i)       \
        ( fstStart[i].parentOrPosition )
#define nextDir(fstStart, i)        \
        ( fstStart[i].nextEntryOrLength )
#define filePosition(fstStart, i)       \
        ( fstStart[i].parentOrPosition )
#define fileLength(fstStart, i)         \
        ( fstStart[i].nextEntryOrLength )

namespace
{

inline
wchar_t*
GetStringPtr(
    wchar_t*    str,
    size_t      offset
)
{
    return
        reinterpret_cast<wchar_t*>(
            reinterpret_cast<u8*>(str) + offset
        );
}

inline
const wchar_t*
GetStringPtr(
    const wchar_t*  str,
    size_t          offset
)
{
    return
        reinterpret_cast<const wchar_t*>(
            reinterpret_cast<const u8*>(str) + offset
        );
}

#if defined(_MSC_VER) && _MSC_VER >= 1500
    #pragma warning(push)
    #pragma warning(disable: 4996)
#endif

inline
size_t
WcsToMbs(
   char*            mbstr,
   const wchar_t*   wcstr,
   size_t           count
)
{
    return std::wcstombs(mbstr, wcstr, count);
}

#if defined(_MSC_VER) && _MSC_VER >= 1500
    #pragma warning(pop)
#endif

}   // namespace

bool ARCInitHandle(void* arcStart, ARCHandle* handle)
{
    FSTEntry*           FSTEntries;
    ARCHeader*          arcHeader;

    arcHeader = (ARCHeader*)arcStart;

    NN_ASSERTMSG(arcHeader->signature == DARCH_SIGNATURE,       "ARCInitHandle: bad archive format");
    NN_ASSERTMSG(arcHeader->byteOrder == DARCH_BYTE_ORDER_MARK, "ARCInitHandle: bad archive format");
    NN_ASSERTMSG(arcHeader->version   == DARCH_VERSION,         "ARCInitHandle: bad archive format");
    
    handle->archiveStartAddr = arcStart;
    handle->FSTStart = FSTEntries = reinterpret_cast<FSTEntry*>((u32)arcStart + arcHeader->fstStart);
    handle->fileStart = (void*)((u32)arcStart + arcHeader->fileStart);

    NN_ASSERTMSG(FSTEntries != NULL, "ARCInitHandle: bad archive format");

    handle->entryNum = nextDir(FSTEntries, 0);
    handle->FSTStringStart = reinterpret_cast<wchar_t*>(&(FSTEntries[handle->entryNum]));
    handle->FSTLength = (u32)arcHeader->fstSize;
    handle->currDir = 0;

    return true;
}

bool ARCOpen(ARCHandle* handle, const wchar_t* fileName, ARCFileInfo* af)
{
    s32         entry;
    FSTEntry*   FSTEntries;
    
    NN_ASSERTMSG( handle, "ARCOpen(): NULL pointer is specified to ARCHandle structure" );
    NN_ASSERTMSG( fileName, "ARCOpen(): NULL pointer is specified to fileName" );
    NN_ASSERTMSG( af, "ARCOpen(): NULL pointer is specified to ARCFileInfo structure" );

    FSTEntries = (FSTEntry*)handle->FSTStart;

    entry = ARCConvertPathToEntrynum(handle, fileName);

#if defined(NW_DEBUG)
    if (0 > entry)
    {
        const size_t BufMax = 127;
        wchar_t     currentDir[BufMax + 1];
        char chBuf[BufMax + 1];
        WcsToMbs(chBuf, fileName, BufMax);
        chBuf[BufMax] = '\0';
        NN_LOG("Warning: ARCOpen(): file '%s' was not found", chBuf);
        ARCGetCurrentDir(handle, currentDir, BufMax + 1);
        WcsToMbs(chBuf, currentDir, BufMax);
        chBuf[BufMax] = '\0';
        NN_LOG(" under %s in the archive.\n", chBuf);
        NN_ASSERT(false);
    }
#endif

    NN_ASSERTMSG( !entryIsDir(FSTEntries, entry), "ARCOpen(): %s is a directory", fileName );

    if ( (entry < 0) || entryIsDir(FSTEntries, entry) )
    {
        return false;
    }

    af->handle      = handle;
    af->startOffset = filePosition(FSTEntries, entry);
    af->length      = fileLength(FSTEntries, entry);

    return true;
}

bool ARCFastOpen(ARCHandle* handle, s32 entrynum, ARCFileInfo* af)
{
    FSTEntry*           FSTEntries;

    NN_ASSERTMSG(handle, "ARCFastOpen(): null pointer is specified to ARCHandle address  ");
    NN_ASSERTMSG(af,
              "ARCFastOpen(): null pointer is specified to ARCFileInfo address  ");
    NN_ASSERTMSG((0 <= entrynum) && (entrynum < static_cast<s32>(handle->entryNum)),
               "ARCFastOpen(): specified entry number '%d' is out of range  ",
               entrynum);

    FSTEntries = (FSTEntry*)handle->FSTStart;

    NN_ASSERTMSG(!entryIsDir(FSTEntries, entrynum),
               "ARCFastOpen(): entry number '%d' is assigned to a directory  ",
               entrynum);

    if ( (entrynum < 0) || (entrynum >= static_cast<s32>(handle->entryNum)) ||
         entryIsDir(FSTEntries, entrynum) )
    {
        return false;
    }

    af->handle      = handle;
    af->startOffset = filePosition(FSTEntries, entrynum);
    af->length      = fileLength(FSTEntries, entrynum);

    return true;
}

 /*---------------------------------------------------------------------------*
    Description:        compare two strings up to the first string hits '/' or
                        '\0'

    Arguments:          path     path name
                        string   directory or file name

    Returns:            true if same, false if not
 *---------------------------------------------------------------------------*/
static bool isSame(const wchar_t* path, const wchar_t* string)
{
    while(*string != '\0')
    {
        // compare in case-insensitive
        if (tolower(*path++) != tolower(*string++))
        {
            return false;
        }
    }

    if ( (*path == '/') || (*path == '\0') )
    {
        return true;
    }

    return false;
}


s32 ARCConvertPathToEntrynum(ARCHandle* handle, const wchar_t* pathPtr)
{
    const wchar_t* ptr;
    wchar_t*     stringPtr;
    bool         isDir;
    s32          length; // must be signed
    u32          dirLookAt;
    u32          i;
    const wchar_t*  origPathPtr = pathPtr;
    FSTEntry*    FSTEntries;


    NN_ASSERTMSG(handle, "ARCConvertPathToEntrynum(): null pointer is specified to ARCHandle structure");
    NN_ASSERTMSG(pathPtr, "ARCConvertPathToEntrynum(): null pointer is specified to file name");
    

    dirLookAt = handle->currDir;
    FSTEntries = (FSTEntry*)handle->FSTStart;

    while (1)
    {

        // check /, ./, ../
        if (*pathPtr == '\0')
        {
            return (s32)dirLookAt;
        } else if (*pathPtr == '/')
        {
            dirLookAt = 0;
            pathPtr++;
            continue;
        }
        else if (*pathPtr == '.')
        {
            if (*(pathPtr + 1) == '.')
            {
                if (*(pathPtr + 2) == '/')
                {
                    dirLookAt = parentDir(FSTEntries, dirLookAt);
                    pathPtr += 3;
                    continue;
                }
                else if (*(pathPtr + 2) == '\0')
                {
                    return (s32)parentDir(FSTEntries, dirLookAt);
                }
            }
            else if (*(pathPtr + 1) == '/')
            {
                pathPtr += 2;
                continue;
            }
            else if (*(pathPtr + 1) == '\0')
            {
                return (s32)dirLookAt;
            }
        }

        // directory or file? Can be checked by the endmark
        for(ptr = pathPtr; (*ptr != '\0') && (*ptr != '/'); ptr++)
            ;
            
        // it's true that one ends with '/' should be a directory name,
        // but one ends with '\0' is not always a file name.
        isDir = (*ptr == '\0')? false : true;
        length = (s32)(ptr - pathPtr);

        ptr = pathPtr;

        for(i = dirLookAt + 1; i < nextDir(FSTEntries, dirLookAt);
            i = entryIsDir(FSTEntries, i)? nextDir(FSTEntries, i): (i+1) )
        {
dot:
            // isDir == false doesn't mean it's a file.
            // so it's legal to compare it to a directory
            if ( ( entryIsDir(FSTEntries, i) == false ) &&
                 (isDir == true) )
            {
                continue;
            }

            stringPtr = GetStringPtr(handle->FSTStringStart, stringOff(FSTEntries, i));

            // check "."
            // support archive files created by "darch[D] -c ."
            if (*stringPtr == '.' && *(stringPtr + 1) == '\0') {
                i++;
                goto dot;
            }

            if ( isSame(ptr, stringPtr) == true )
            {
                goto next_hier;
            }

        } // for()

        return -1;

      next_hier:
        if (! isDir)
        {
            return (s32)i;
        }

        dirLookAt = i;
        pathPtr += length + 1;

    } // while (1)

    // NOT REACHED
}

bool  ARCEntrynumIsDir( const ARCHandle * handle, s32 entrynum )
{
    FSTEntry*           FSTEntries;
    
    NN_ASSERTMSG(handle, "ARCEntrynumIsDir(): null pointer is specified to ARCHandle structure");
    NN_ASSERTMSG((entrynum >= 0) , "ARCEntrynumIsDir(): no file/directory is specified to entrynum");
    FSTEntries = (FSTEntry*)handle->FSTStart;
    
    return entryIsDir( FSTEntries, entrynum );
}

/*---------------------------------------------------------------------------*
  Name:         myStrncpy

  Description:  copy a string. Difference from standard strncpy is:
                    1. do not pad dest with null characters 
                    2. do not terminate dest with a null
                    3. return the number of chars copied

  Arguments:    dest        destination
                src         source
                maxlen      maximum length of copy

  Returns:      Num of chars copied
 *---------------------------------------------------------------------------*/
static u32 myStrncpy(wchar_t* dest, wchar_t* src, u32 maxlen)
{
    u32         i = maxlen;

    while( (i > 0) && (*src != 0) )
    {
        *dest++ = *src++;
        i--;
    }
    
    return (maxlen - i);
}

/*---------------------------------------------------------------------------*
  Name:         entryToPath

  Description:  Convert from fst entry to path. The result is not null
                terminated.

  Arguments:    entry       FST entry
                path        pointer to store the result
                maxlen      size of the buffer start from path

  Returns:      Num of chars copied
 *---------------------------------------------------------------------------*/
static u32 entryToPath(ARCHandle* handle, u32 entry, wchar_t* path, u32 maxlen)
{
    wchar_t*    name;
    u32         loc;
    FSTEntry*    FSTEntries;

    FSTEntries = (FSTEntry*)handle->FSTStart;

    if (entry == 0)
    {
        return 0;
    }

    name = GetStringPtr(handle->FSTStringStart, stringOff(FSTEntries, entry));

    loc = entryToPath(handle, parentDir(FSTEntries, entry), path, maxlen);
    
    if (loc == maxlen)
    {
        return loc;
    }

    *(path + loc++) = '/';

    loc += myStrncpy(path + loc, name, maxlen - loc);
    
    return loc;
}


/*---------------------------------------------------------------------------*
  Name:         ARCConvertEntrynumToPath

  Description:  Convert from fst entry to path.

  Arguments:    entrynum    FST entry
                path        pointer to store the result
                maxlen      size of the buffer start from path

  Returns:      true if all the path fits in maxlen. false if not (in this
                case, it's truncated to fit maxlen).
 *---------------------------------------------------------------------------*/
static bool ARCConvertEntrynumToPath(ARCHandle* handle, s32 entrynum, wchar_t* path, u32 maxlen)
{
    u32         loc;
    FSTEntry*    FSTEntries;


    FSTEntries = (FSTEntry*)handle->FSTStart;
    NN_ASSERTMSG((0 <= entrynum) && (entrynum < static_cast<s32>(handle->entryNum)),
               "ARCConvertEntrynumToPath: specified entrynum(%d) is out of range  ",
                entrynum );
    NN_ASSERTMSG(1 < maxlen, "ARCConvertEntrynumToPath: maxlen should be more than 1 (%d is specified)",
               maxlen );
    // currently only directories can be converted to path
    // finding the directory where a file is located is not so easy
    // while finding the parent directory of a directory is a piece of cake.
    NN_ASSERTMSG(entryIsDir(FSTEntries, entrynum),
              "ARCConvertEntrynumToPath: cannot convert an entry num for a file to path  ");

    loc = entryToPath(handle, (u32)entrynum, path, maxlen);

    if (loc == maxlen)
    {
        // Overwrite the last char with NULL
        path[maxlen - 1] = '\0';
        return false;
    }

    // For directories, put '/' at the last
    if (entryIsDir(FSTEntries, entrynum))
    {
        if (loc == maxlen - 1)
        {
            // There's no room to put the last '/', so just put '\0' and return false
            path[loc] = '\0';
            return false;
        }

        path[loc++] = '/';
    }
    
    path[loc] = '\0';
    return true;
}

/*---------------------------------------------------------------------------*
  Name:         ARCGetCurrentDir

  Description:  Get current directory

  Arguments:    path        pointer to store the result
                maxlen      size of the buffer start from path

  Returns:      true if all the path fits in maxlen. false if not (in this
                case, it's truncated to fit maxlen).
 *---------------------------------------------------------------------------*/
bool ARCGetCurrentDir(ARCHandle* handle, wchar_t* path, u32 maxlen)
{
    NN_ASSERTMSG( 1 < maxlen, "ARCGetCurrentDir: maxlen should be more than 1 (%d is specified)",
                maxlen );

    return ARCConvertEntrynumToPath(handle, (s32)handle->currDir, path, maxlen);
}

void* ARCGetStartAddrInMem(ARCFileInfo* af)
{
    ARCHandle* handle;

    handle = af->handle;

    NN_ASSERTMSG(handle, "ARCGetFileAddr(): af->handle is null pointer. Maybe it's not initialized properly");
    NN_ASSERTMSG(af, "ARCGetFileAddr(): null pointer is specified to ARCFileInfo structure");
    
    return (void*)( (u32)handle->archiveStartAddr + af->startOffset );
}

u32 ARCGetStartOffset(ARCFileInfo* af)
{
    return af->startOffset;
}

u32 ARCGetLength(ARCFileInfo* af)
{
    return af->length;
}


bool ARCClose(ARCFileInfo* af)
{
    NN_UNUSED_VAR(af);

    return true;
}

bool ARCChangeDir(ARCHandle* handle, const wchar_t* dirName)
{
    s32         entry;
    FSTEntry*   FSTEntries;

    NN_ASSERTMSG(handle, "ARCChangeDir(): null pointer is specified to ARCHandle");
    NN_ASSERTMSG(dirName, "ARCChangeDir(): null pointer is specified to dirname");

    entry = ARCConvertPathToEntrynum(handle, dirName);
    FSTEntries = (FSTEntry*)handle->FSTStart;

#if defined(NW_DEBUG)
    if (0 > entry)
    {
        const size_t BufMax = 127;
        wchar_t currentDir[BufMax + 1];
        char chBuf[BufMax + 1];
        WcsToMbs(chBuf, dirName, BufMax);
        chBuf[BufMax] = '\0';
        NN_LOG("ARCOpendir(): directory '%s' is not found", chBuf);
        ARCGetCurrentDir(handle, currentDir, BufMax + 1);
        WcsToMbs(chBuf, currentDir, BufMax);
        chBuf[BufMax] = '\0';
        NN_LOG(" under %s  ", chBuf);
        NN_ASSERT(false);
    }
#endif
    NN_ASSERTMSG(entryIsDir(FSTEntries, entry), "ARCChangeDir(): %s is not a directory", dirName );

    if ( (entry < 0) || (entryIsDir(FSTEntries, entry) == false) )
    {
        return false;
    }

    handle->currDir = (u32)entry;

    return true;
}

bool ARCChangeDir(ARCHandle* handle, s32 entrynum)
{
    NN_ASSERTMSG(
        handle != NULL,
        "ARCChangeDir(): null pointer is specified to ARCHandle address");

    NN_ASSERTMSG(
        (0 <= entrynum) && (entrynum < static_cast<s32>(handle->entryNum)),
        "ARCChangeDir(): specified entry number '%d' is out of range",
        entrynum);

    FSTEntry* FSTEntries = (FSTEntry*)handle->FSTStart;

    NN_ASSERTMSG(
        entryIsDir(FSTEntries, entrynum),
        "ARCChangeDir(): %s entry[%d] a regular file", entrynum);

    if (handle == NULL)
    {
        return false;
    }

    if (entrynum < 0 || static_cast<s32>(handle->entryNum) <= entrynum)
    {
        return false;
    }

    if (!entryIsDir(FSTEntries, entrynum))
    {
        return false;
    }

    handle->currDir = (u32)entrynum;

    return true;
}

bool ARCOpenDir(ARCHandle* handle, const wchar_t* dirName, ARCDir* dir)
{
    s32         entry;
    FSTEntry*   FSTEntries;

    NN_ASSERTMSG(handle, "ARCOpenDir(): null pointer is specified to ARCHandle");
    NN_ASSERTMSG(dirName, "ARCOpenDir(): null pointer is specified to ARCDir");

    entry = ARCConvertPathToEntrynum(handle, dirName);
    FSTEntries = (FSTEntry*)handle->FSTStart;

#if defined(NW_DEBUG)
    if (entry < 0)
    {
        const size_t BufMax = 127;
        wchar_t currentDir[BufMax + 1];
        char chBuf[BufMax + 1];
        WcsToMbs(chBuf, dirName, BufMax);
        chBuf[BufMax] = '\0';
        NN_LOG("ARCOpenDir(): directory '%s' is not found", chBuf);
        ARCGetCurrentDir(handle, currentDir, BufMax + 1);
        WcsToMbs(chBuf, currentDir, BufMax);
        chBuf[BufMax] = '\0';
        NN_LOG(" under %s  ", chBuf);
        NN_ASSERT(false);
    }
#endif

    NN_ASSERTMSG( entryIsDir(FSTEntries, entry), "ARCOpenDir(): %s is a regular file", dirName );

    if ( (entry < 0) || (entryIsDir(FSTEntries, entry) == false) )
        return false;

    dir->handle = handle;
    dir->entryNum = (u32)entry;
    dir->location = (u32)entry + 1;
    dir->next = nextDir(FSTEntries, entry);

    return true;
}

bool ARCOpenDir(ARCHandle* handle, s32 entrynum, ARCDir* dir)
{
    NN_ASSERTMSG(
        handle != NULL,
        "ARCOpenDir(): null pointer is specified to ARCHandle address");

    NN_ASSERTMSG(
        (0 <= entrynum) && (entrynum < static_cast<s32>(handle->entryNum)),
        "ARCOpenDir(): specified entry number '%d' is out of range",
        entrynum);

    FSTEntry* FSTEntries = (FSTEntry*)handle->FSTStart;

    NN_ASSERTMSG(
        entryIsDir(FSTEntries, entrynum),
        "ARCOpenDir(): %s entry[%d] a regular file", entrynum);

    if (handle == NULL)
    {
        return false;
    }

    if (entrynum < 0 || static_cast<s32>(handle->entryNum) <= entrynum)
    {
        return false;
    }

    if (!entryIsDir(FSTEntries, entrynum))
    {
        return false;
    }

    dir->handle = handle;
    dir->entryNum = (u32)entrynum;
    dir->location = (u32)entrynum + 1;
    dir->next = nextDir(FSTEntries, entrynum);

    return true;
}

bool ARCReadDir(ARCDir* dir, ARCDirEntry* dirent)
{
    u32         loc;
    FSTEntry*   FSTEntries;
    ARCHandle*  handle;

    handle = dir->handle;

    NN_ASSERTMSG(handle, "ARCReadDir: dir->handle is null pointer. Maybe it's not initialized properly");
    
    FSTEntries = (FSTEntry*)handle->FSTStart;

    // Check the next location. loc == dir->next means it reached the
    // end of the directory. Other check is for illegal setting by ARCSeekDir.
    loc = dir->location;
retry:
    if ( (loc <= dir->entryNum) || (dir->next <= loc) )
        return false;

    dirent->handle = handle;
    dirent->entryNum = loc;
    dirent->isDir = entryIsDir(FSTEntries, loc);
    dirent->name = GetStringPtr(handle->FSTStringStart, stringOff(FSTEntries, loc));

    // check "."
    // support archive files created by "darch[D] -c ."
    if (dirent->name[0] == '.' && dirent->name[1] == '\0') {
        loc++;
        goto retry;
    }

    dir->location = entryIsDir(FSTEntries, loc)? nextDir(FSTEntries, loc) : (loc+1);

    return true;
}

bool ARCCloseDir(ARCDir* dir)
{
    NN_UNUSED_VAR(dir);

    return true;
}

} // namespace lyt
} // namespace nw