/*

* Copyright (c) 2010 Nokia Corporation and/or its subsidiary(-ies).

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of the License "Eclipse Public License v1.0"

* which accompanies this distribution, and is available

* at the URL "http://www.eclipse.org/legal/epl-v10.html".

*

* Initial Contributors:

* Nokia Corporation - initial contribution.

*

* Contributors:

*

* Description: 

*

*/

#include "fsnode.h"

#include "fatdefines.h"

#include "utf16string.h"

#include <stdio.h> 

#include <iostream>

#include <iomanip>

#include <stdio.h> 

#include <stdlib.h> 

#include <ctype.h> 

using namespace std;

const TUint KBytesPerEntry = 13 ;

static inline bool is_a_long_file_name_char(unsigned char ch){

	return ( ch >= ' ' && ch != '"' && ch != '*' && ch != ':' && ch != '<' \

		&& ch != '>' && ch != '?' && ch != '|' && ch != 127) ; 

}

//

TFSNode::TFSNode(TFSNode* aParent, const char* aFileName, TUint8 aAttrs, const char* aPCSideName)  :

iParent(aParent),iFirstChild(0),iSibling(0),iAttrs(aAttrs), iPCSideName(0), iWideName(0){

  // According to the FAT specification, short name should be inited with empty string (' ' string)

	memset(iShortName,0x20,11);  

	iShortName[11] = 0 ; 

	if(aFileName) {

		const unsigned char* ptr = reinterpret_cast<const unsigned char*>(aFileName);

		bool allSpaces = true ;

		while(*ptr){

			if( !is_a_long_file_name_char(*ptr))

				throw "Illegal filename or dir name! \n";		

			if(*ptr != ' ')

				allSpaces = false ;		

			ptr++ ;

		}

		if(allSpaces)

			throw "Illegal filename or dir name(all spaces)!\n";

		iFileName = strdup(aFileName); 

		GenerateBasicName() ;	

	} 

	if(aPCSideName) {

		iPCSideName = strdup(aPCSideName);

	}

	iFATEntry = 0;

	iCrtTimeTenth  = 0;

	iCrtTime.iImageTime = 0 ;

	iCrtDate.iImageDate = 0 ;

	iLstAccDate.iImageDate = 0  ;

	iWrtTime.iImageTime = 0 ;

	iWrtDate.iImageDate = 0  ;

	iFileSize = 0;

	if(!iParent) return ;

	if(!iParent->iFirstChild)

	    iParent->iFirstChild = this ;

    else {

        TFSNode* sibling = iParent->iFirstChild;

        while(sibling->iSibling)

            sibling = sibling->iSibling ;

        sibling->iSibling = this ;

    } 

}

TFSNode::~TFSNode(){

	if(iFirstChild)

		delete iFirstChild ;

	if(iSibling)

		delete iSibling ;

	if(iFileName)

		free(iFileName) ;

	if(iWideName)

		delete iWideName;

	if(iPCSideName)

		free(iPCSideName);

}

/** GenerateBasicName : Generate the short name according to long name 

	* 

	* algorithm :

	* 

	* 1.	The UNICODE name passed to the file system is converted to upper case.

	* 2.	The upper cased UNICODE name is converted to OEM.

	*     if (the uppercased UNICODE glyph does not exist as an OEM glyph in the OEM code page)

	*				or	(the OEM glyph is invalid in an 8.3 name)

	*			{

	*				Replace the glyph to an OEM '_' (underscore) character.

	*				Set a "lossy conversion" flag.

	*			}

	* 3.	Strip all leading and embedded spaces from the long name.

	* 4.	Strip all leading periods from the long name.

	* 5.	While		(not at end of the long name)

	*					and	(char is not a period)

	*					and	(total chars copied < 8)

	*			{

	*				Copy characters into primary portion of the basis name

	*			}

	*	6.	Insert a dot at the end of the primary components of the basis-name 

	*     if the basis name has an extension after the last period in the name.

	*

	* 7.	Scan for the last embedded period in the long name.

	*     If	(the last embedded period was found)

	*     {

	*     	While		(not at end of the long name) and	(total chars copied < 3)

	*     	{

	*     		Copy characters into extension portion of the basis name

	*     	}

	*     }

  *

  */

void TFSNode::GenerateBasicName() { 

	const char* filename =  iFileName ;	 

	TUint length = strlen(filename);

	if(0 == length)

	    return ;

	if(0 == strcmp(filename,".")){

        iShortName[0] = '.' ;

        return ;

	}

	if(0 == strcmp(filename,"..")){

        iShortName[0] = '.' ;

        iShortName[1] = '.' ;

        return ;

	} 

	iWideName = new UTF16String(filename,length); // The unicode string

	char base[10];

	const char* ext = filename + length;

	//Strip all leading periods and spaces from the long name.

	while(*filename == '.' || *filename == ' ' || *filename == '\t') {

		filename ++ ;

		length -- ;

	}

	//find the extension

	while(ext > filename && *ext != '.')

		ext -- ;

	if(ext == filename){

		ext = "" ; 

	}

	else {

		length = ext - filename;

		ext ++ ;

	} 

	bool lossyConv = false ;

	TUint bl = 0;

	for(TUint i = 0 ; i < length ; i++) {

		if(filename[i] >= 'a' && filename[i] <= 'z')

			base[bl++] = filename[i] + 'A' - 'a';

		else if(filename[i] >= 'A' && filename[i] <= 'Z')

			base[bl++] = filename[i];

		else if(filename[i] == '$' || filename[i] == '%' ||

			filename[i] == '-' || filename[i] == '_' || filename[i] == '@' ||

			filename[i] == '~' || filename[i] == '`' || filename[i] == '!' ||

			filename[i] == '(' || filename[i] == ')' || filename[i] == '{' ||

			filename[i] == '}' || filename[i] == '^' || filename[i] == '#' ||

			filename[i] == '&' ||filename[i] == '\'')

			base[bl++] = filename[i];

		else if(filename[i] != ' ' && filename[i] != '.'){

			base[bl++] = '_';

			lossyConv = true ;

		}

		if(bl > 8){

			bl -- ;

			lossyConv = true ;

			break ;

		}		

	}

	if(lossyConv){

		if(bl > 6) bl = 6 ;		

		iShortName[bl] = '~';

		iShortName[bl+1] = '1';		

	}

	memcpy(iShortName,base,bl);

	//Copy the extension part.	

	TUint ei = 8;

	for(TUint e = 0; ei < 11 && ext[e] != 0 ; e++){

		if(ext[e] >= 'a' && ext[e] <= 'z')

			iShortName[ei++] = ext[e] + 'A' - 'a';

		else if(ext[e] >= 'A' && ext[e] <= 'Z')

			iShortName[ei++] = ext[e] ;

		else if(ext[e] == '$' || ext[e] == '%' || ext[e] == '-' || ext[e] == '_' || 

			ext[e] == '@' || ext[e] == '~' || ext[e] == '`' || ext[e] == '!' || 

			ext[e] == '(' || ext[e] == ')' || ext[e] == '{' || ext[e] == '}' || 

			ext[e] == '^' || ext[e] == '#' || ext[e] == '&' ||ext[e] == '\'')

			iShortName[ei++] = ext[e] ;

	}

	if(iParent) 

		iParent->MakeUniqueShortName(iShortName,bl); 

}

#ifdef _DEBUG

void TFSNode::PrintTree(int nTab) {

	for( int i = 0 ; i < nTab ; i++ )

		cout << " " ;

	cout << (iFileName ? iFileName : "") << " [" << hex << setw(2) << setfill('0') << (unsigned short)iAttrs << "] \n" ;

	if(iFirstChild)

		iFirstChild->PrintTree(nTab + 2);

	if(iSibling)

		iSibling->PrintTree(nTab);

}

#endif

bool TFSNode::IsDirectory() const {

	return (0 != (iAttrs & ATTR_DIRECTORY) || ATTR_VOLUME_ID == iAttrs) ;

}

int TFSNode::GetWideNameLength() const {

	if(!iWideName)

		return 0 ;

	return iWideName->length() ;

}

TUint TFSNode::GetSize() const {

	if( !IsDirectory())

		return iFileSize ;

	TUint retVal = sizeof(TShortDirEntry) ; // the tailed entry 

	if(iParent)

		retVal += sizeof(TShortDirEntry) * 2 ;

	TFSNode* child = iFirstChild ;

	while(child) {

		TUint longNameEntries =  (child->GetWideNameLength() + KBytesPerEntry) / KBytesPerEntry  ;

		retVal += longNameEntries * sizeof(TLongDirEntry) ;

		retVal += sizeof(TShortDirEntry);

		child = child->iSibling ;

	}

	return retVal ;

}

void TFSNode::Init(time_t aCreateTime, time_t aAccessTime, time_t aWriteTime, TUint aSize ) {

	struct tm* temp = localtime(&aCreateTime);

	iCrtDate.iCurrentDate.Day = temp->tm_mday;

	iCrtDate.iCurrentDate.Month = temp->tm_mon+1; //As per FAT spec

	iCrtDate.iCurrentDate.Year = temp->tm_year - 80;//As per FAT spec

	iCrtTime.iCurrentTime.Hour = temp->tm_hour;

	iCrtTime.iCurrentTime.Minute = temp->tm_min;

	iCrtTime.iCurrentTime.Seconds = temp->tm_sec / 2;//As per FAT spec

	iCrtTimeTenth = 0;

	temp = localtime(&aAccessTime);	

	iLstAccDate.iCurrentDate.Day = temp->tm_mday;

	iLstAccDate.iCurrentDate.Month = temp->tm_mon+1; //As per FAT spec

	iLstAccDate.iCurrentDate.Year = temp->tm_year - 80;//As per FAT spec

	temp = localtime(&aWriteTime);

	iWrtDate.iCurrentDate.Day = temp->tm_mday;

	iWrtDate.iCurrentDate.Month = temp->tm_mon+1; //As per FAT spec

	iWrtDate.iCurrentDate.Year = temp->tm_year - 80;//As per FAT spec

	iWrtTime.iCurrentTime.Hour = temp->tm_hour;

	iWrtTime.iCurrentTime.Minute = temp->tm_min;

	iWrtTime.iCurrentTime.Seconds = temp->tm_sec / 2;//As per FAT spec 

	iFileSize = aSize ; 

}

/** WriteDirEntries : Write FAT information for this node to a cluster buffer

	* aStartIndex : [in],the beginning index of the outputed cluster  

  * aClusterData : [in,out] the cluster buffer

  * 

  * notice, aClusterData is only required if node is a directory node.

  * for a file node, no data will be written out.

  * in this case, only corresponding cluster index information is updated.

  */ 

void TFSNode::WriteDirEntries(TUint aStartIndex,TUint8* aClusterData){

	if(iFATEntry){

		*((TUint16*)iFATEntry->DIR_FstClusHI) = (aStartIndex >> 16) ;

		*((TUint16*)iFATEntry->DIR_FstClusLO) = (aStartIndex & 0xFFFF) ;

	}

	if(IsDirectory()) { // Directory , write dir entries ; 

		TShortDirEntry* entry = reinterpret_cast<TShortDirEntry*>(aClusterData);

		if(iParent != NULL) {

			//Make 

			GetShortEntry(entry); 

			//TODO: Add comments to avoid mistaken deleting.			

			memcpy(entry->DIR_Name,".            ",sizeof(entry->DIR_Name));

			entry ++ ;

			iParent->GetShortEntry(entry);

			memcpy(entry->DIR_Name,"..           ",sizeof(entry->DIR_Name));

			entry ++ ; 

		}		 

		TFSNode* child = iFirstChild ;

		while(child){			

			int items = child->GetLongEntries(reinterpret_cast<TLongDirEntry*>(entry));

			entry += items ;

			child->GetShortEntry(entry);

			child->iFATEntry = entry ;

			entry ++ ;

			child = child->iSibling ; 

		}

	}

}

/** GetShortEntry : Make a short directory entry (FAT16/32 conception)

  * aEntry : the entry buffer   

  */ 

void TFSNode::GetShortEntry(TShortDirEntry* aEntry) {

  if(!aEntry) return ;

	if(iFATEntry){

		if(iFATEntry != aEntry)

			memcpy(aEntry,iFATEntry,sizeof(TShortDirEntry));

		return ;

	}

	memcpy(aEntry->DIR_Name,iShortName,sizeof(aEntry->DIR_Name)); 

	aEntry->DIR_Attr = iAttrs;

	aEntry->DIR_NTRes = 0 ;

	aEntry->DIR_CrtTimeTenth = 0 ;        

	memcpy(aEntry->DIR_CrtTime,&iCrtTime,sizeof(aEntry->DIR_CrtTime)); 

	memcpy(aEntry->DIR_CrtDate,&iCrtDate,sizeof(aEntry->DIR_CrtDate));

	memcpy(aEntry->DIR_LstAccDate,&iLstAccDate,sizeof(aEntry->DIR_LstAccDate));

	memset(aEntry->DIR_FstClusHI,0,sizeof(aEntry->DIR_FstClusHI));

	memcpy(aEntry->DIR_WrtTime,&iWrtTime,sizeof(aEntry->DIR_WrtTime)); 

	memcpy(aEntry->DIR_WrtDate,&iWrtDate,sizeof(aEntry->DIR_WrtDate)); 

	memset(aEntry->DIR_FstClusLO,0,sizeof(aEntry->DIR_FstClusLO)); 

	memcpy(aEntry->DIR_FileSize,&iFileSize,sizeof(aEntry->DIR_FileSize));  

}

TUint8 FATChkSum(const char* pFcbName) {

    short fcbNameLen ;

    TUint8 sum = 0 ;

    for(fcbNameLen = 11 ; fcbNameLen != 0 ; fcbNameLen --) {

        sum = ((sum & 1) ? 0x80 : 0 ) + (sum >> 1 ) + *pFcbName++ ; 

    }

    return sum ;        

}

/** GetLongEntries : Make a series of long directory entries (FAT16/32 conception)

  * aEntries : the start addr of the long directory entries buffer

  *

  * return value : actual entris count.   

  */ 

int TFSNode::GetLongEntries(TLongDirEntry* aEntries) {

  if(!aEntries) return 0;

	int packs = (GetWideNameLength() + KBytesPerEntry) / KBytesPerEntry  ;

	TUint buflen = packs * KBytesPerEntry;

	TUint16* buffer = new(std::nothrow) TUint16[buflen];

	if(!buffer)

	return 0 ;

	memset(buffer,0xff,(buflen << 1));    

	if(iWideName) {

	    memcpy(buffer,iWideName->c_str(),iWideName->bytes()); 

	    buffer[iWideName->length()] = 0;

	}

	TUint8 chkSum = FATChkSum(iShortName);;

	TUint16* ptr = buffer ;

	TLongDirEntry* entry = aEntries +(packs - 1);

  for(int i = 1 ; i <= packs ; i++, entry--) {		

		entry->LDIR_Ord = i ;

		entry->LDIR_Chksum = chkSum ;

		entry->LDIR_Attr = (TUint8)ATTR_LONG_NAME;    

		*((TUint16*)(entry->LDIR_FstClusLO)) = 0;

		entry->LDIR_Type = 0;         

		memcpy(entry->LDIR_Name1,ptr,10); 

		memcpy(entry->LDIR_Name2,&ptr[5],12); 

		memcpy(entry->LDIR_Name3,&ptr[11],4);

		ptr += 13; 

  }

	aEntries->LDIR_Ord |= 0x40 ;

	delete []buffer ;

	return packs ; 

}

/** Make a unique name for a new child which has not been added.

  * to avoid same short names under a directory

  * rShortName : [in,out] , The new short name to be checked and changed.

  * baseNameLength: [in], the length of the base part of the short name 

  * not including the "~n"

  * for example, 

  *  "ABC.LOG" => baseNameLength == 3 ("ABC")

  *  "AB~1.TXT" => baseNameLength == 2 ("AB")

  *

  *

  *The Numeric-Tail Generation Algorithm

  * If (a "lossy conversion" was not flagged)

  * 		and	(the long name fits within the 8.3 naming conventions)

  * 		and	(the basis-name does not collide with any existing short name)

  * {

  * 	The short name is only the basis-name without the numeric tail.

  * }

  * else {

  * 	Insert a numeric-tail "~n" to the end of the primary name such that the value of 

  *		the "~n" is chosen so that the name thus formed does not collide with 

  *		any existing short name and that the primary name does not exceed eight

  *		characters in length.

  * }

  * The "~n" string can range from "~1" to "~999999". 

  *

  */

void TFSNode::MakeUniqueShortName(char rShortName[12],TUint baseNameLength) const { 

	bool dup ;

	char nstring[10];

	int n = 0 ;	

	do {

		TFSNode* child = iFirstChild ; 

		dup = false ;

		while(child){		 

			if(0 == memcmp(rShortName,child->iShortName,11)) {

				dup = true ;

				break ;

			}

			child = child->iSibling ;

		}

		if(dup){ //duplex , increase the index , make a new name 

			int nlen = sprintf(nstring,"~%u",++n);

			while((baseNameLength + nlen > 8) && baseNameLength > 1)

				baseNameLength -- ;

			memcpy(&rShortName[baseNameLength],nstring,nlen);

		}

	}while(dup) ;

}