/*

* Copyright (c) 2004-2005 Nokia Corporation and/or its subsidiary(-ies).

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of "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:

*

*/

/**    @file

   @internalComponent */

#include "ImageDisplayResolvrUtils.h"

//

// COpaqueDataParse

//    Class for reading and processing opaque data from the ECOM resource file

//    We store this as follows:

//		Version (1 byte)

// 		flags (2 bytes)

//		Main Uid (4 bytes)

//		Sub Uid (4 bytes)

//		Number extensions (1 byte)

//		{ ".XXX" \r } (x number extensions)

//		Number mime types (1 byte)

//		[ "mimetype" \r ] (for each mimetype)

//

// Note to avoid overhead, we only read the extensions and mime types on demand

// Until EnsureExtnsReadL() is called, ExtnsCount() and Extn is invalid. Similarly

// for mime types.

COpaqueDataParse* COpaqueDataParse::NewL(const TDesC8& aOpaqueData)

	{

	COpaqueDataParse* result = COpaqueDataParse::NewLC(aOpaqueData);

	CleanupStack::Pop(result);

	return result;

	}

COpaqueDataParse* COpaqueDataParse::NewLC(const TDesC8& aOpaqueData)

	{

	COpaqueDataParse* result = new (ELeave) COpaqueDataParse(aOpaqueData);

	CleanupStack::PushL(result);

	result->ConstructL();

	return result;

	}

COpaqueDataParse::COpaqueDataParse(const TDesC8& aOpaqueData):

	iOpaqueData(aOpaqueData)

	{

	}

void COpaqueDataParse::ConstructL()

	{

	ReadVersion();

	if (iVersion < KIclPluginFrameworkVersionOne || 

		iVersion > KIclPluginFrameworkVersionMax)

		User::Leave(KErrNotSupported);

	ReadFlags();

	ReadUids();

	}

COpaqueDataParse::~COpaqueDataParse()

	{

	iArray.Close();

	}

// Extract the Version number 

void COpaqueDataParse::ReadVersion()

	{

	ASSERT(iState<=EVersionProcessed); // should only call this on construction

	ASSERT(iOpaqueData.Length() >= KIndexForVersion + 1);

	//The version is one byte

	iVersion = iOpaqueData[KIndexForVersion];

	iState = EVersionProcessed;

	}

// Extract the (optional) flags

void COpaqueDataParse::ReadFlags()

	{

	ASSERT(iState<EFlagsProcessed);

	switch(iVersion)

		{

		case KIclPluginFrameworkVersionOne:

			ASSERT(iOpaqueData.Length() >= KIndexForFlags + 2); // opaque data not valid otherwise

			iFlags = (iOpaqueData[KIndexForFlags+0] << 8) | (iOpaqueData[KIndexForFlags+1]);

			iLenOfFlags = 2;

			break;

		}

	iStartOfUids = 1 + iLenOfFlags;

	iStartOfNumberOfExtns = 1 + iLenOfFlags + 8;

	iState = EFlagsProcessed;

	}

// Extract the two Uids 

void COpaqueDataParse::ReadUids()

	{

	ASSERT(iState<EUidsProcessed);

	ASSERT(iOpaqueData.Length() >= iStartOfUids + 4); // opaque data not valid otherwise

	// A given OpaqueData should either contain one Uid, in 4 bytes,

	// highest to lowest, with an implied second Uid set to KNullUid,

	// or two consecutive Uids, in 4 bytes each - 8 in all - main type followed by sub-type.

	// The 8 bytes may be followed, for basic types, by info on the file extensions

	// and MIME typesassociated with this plugin but this info is ignored here.

	iImageTypeUid.iUid = (iOpaqueData[iStartOfUids] << 24) | (iOpaqueData[iStartOfUids+1] << 16) | (iOpaqueData[iStartOfUids+2] << 8) | (iOpaqueData[iStartOfUids+3]);

	if (iOpaqueData.Length() == iStartOfUids + 4)

		{

		iImageSubTypeUid = KNullUid;

		}

	else

		{

		ASSERT(iOpaqueData.Length() >= iStartOfUids + 8);

		iImageSubTypeUid.iUid = (iOpaqueData[iStartOfUids+4] << 24) | (iOpaqueData[iStartOfUids+5] << 16) + (iOpaqueData[iStartOfUids+6] << 8) + (iOpaqueData[iStartOfUids+7]);

		}

	iState = EUidsProcessed;

	}

// read in the Extns from the opaque data

void COpaqueDataParse::EnsureExtnsReadL()

	{

	// if we've already read in the extensions, is a NOP

	if (iState>=EExtnsProcessed)

		{

		return;

		}

	ASSERT(iArray.Count()==0); // assume nothing in there at the moment

	iExtnCount = iOpaqueData[iStartOfNumberOfExtns];

	TInt pos = iStartOfNumberOfExtns+1; // start just after the extn count byte	

	for (TInt index=0; index<iExtnCount; index++)

		{

		TPtrC8 restOfData = iOpaqueData.Mid(pos);

		TInt endPos = restOfData.Locate(TChar('\r')); // \r is used to terminate each suffix

		ASSERT(endPos != KErrNotFound); // if we have -1, would not have found the CR

		TPtrC8 extn = restOfData.Left(endPos);

		User::LeaveIfError(iArray.Append(extn));

		pos += endPos + 1; // skip over the CR

		}

	iStartOfMimeTypes = pos;

	iState = EExtnsProcessed;

	ASSERT(iArray.Count()==iExtnCount);

	}

void COpaqueDataParse::EnsureMIMETypesReadL()

	{

	// if we've already read in the mime types, is a NOP

	if (iState>=EMIMETypesProcessed)

		return;

	EnsureExtnsReadL();

	ASSERT(iState==EExtnsProcessed);

	TInt pos = iStartOfMimeTypes;

	const TInt numMimeTypes = iOpaqueData[pos];

	pos += 1;

	for (TInt index=0; index<numMimeTypes; index++)

		{

		TPtrC8 restOfData = iOpaqueData.Mid(pos);

		TInt endPos = restOfData.Locate(TChar('\r')); // \r is used to terminate each suffix

		ASSERT(endPos != KErrNotFound); // if we have -1, would not have found the CR

		TPtrC8 mimeType = restOfData.Left(endPos);

		User::LeaveIfError(iArray.Append(mimeType));

		pos += endPos + 1; // skip over the CR

		}

	iState = EMIMETypesProcessed;

	ASSERT(iArray.Count()==iExtnCount+numMimeTypes);

	}

TBool COpaqueDataParse::CompareMIMETypes(const TDesC8& aMimeType1, const TDesC8& aMimeType2)

	{

	if (aMimeType1.Length() != aMimeType2.Length())

		{

		return EFalse;

		}

	return aMimeType1.CompareF(aMimeType2)==0; // true if exactly the same, if we ignore the case

	}

TBool COpaqueDataParse::CompareFileSuffixL(const TDesC& aFileSuffix1, const TDesC8& aFileSuffix2)

	{

	//First do a quick compare

	if (aFileSuffix1.Length() != aFileSuffix2.Length())

		{

		return EFalse;

		}

	//Change aFileSuffix2 from TDesC8 to TDesC

	HBufC* fileSuffix = HBufC::NewL(aFileSuffix2.Length()); //Not on CleanupStack since nothing can leave

	TPtr fileSuffixPtr(fileSuffix->Des());

	fileSuffixPtr.Copy(aFileSuffix2);

	const TBool result = aFileSuffix1.CompareF(*fileSuffix)==0; // true if exactly the same, if we ignore the case

	delete fileSuffix;

	return result;

	}

/*

 * 

 * Searches for a match of aPluginString in aClientString. Match returns ETrue

 * if aPluginString is found within aImplementationType according to the

 * following rules:

 * 1) All bytes in aClientString are exact but instances of '?' (0x3F) in

 *    aPluginString are treated as wildcards - matching any byte value at that

 *    position in aClientString.

 * 2) If aClientString is longer than aPluginString, ignore any excess bytes.

 * 3) aClientString is treated as a single descriptor - the '||' delimiters

 *    are not recognised.

 * 4) ETrue is returned if aPluginString matches the start of aClientString

 *    exactly, subject to wildcards.

 * 5) aBytesMatched will be filled in with the number of non-wildcard bytes in

 *    aPluginString. This is used to rank matches.

 *

 * @param     "const TDesC8& aClientString"

 *            The string from the client to search for a match

 * @param     "const TDesC8& aPluginString"

 *            The data to search for from the plugin

 * @param     "TInt& aBytesMatched"

 *            The number of non-wildcard bytes matched, or "1" if the match pattern contains only "?"

				i.e. should match any data

 * @return    "TBool"

 *            ETrue if a match was found, EFalse otherwise

 */

TBool CImageDisplayResolverUtils::Match(const TDesC8& aClientString, const TDesC8& aPluginString, TInt& aBytesMatched)

	{

	TInt pluginStringLength = aPluginString.Length();

	aBytesMatched = 0;

	while (pluginStringLength>1 && (aPluginString[pluginStringLength - 1] == '?'))

		{ // Clip extraneous '?' wildcards off the end of the plugin match string

		pluginStringLength--;

		}

	if (pluginStringLength == 0)

		{ // Plugin has no match string

		return EFalse;

		}

	if (aClientString.Length() < pluginStringLength)

		{ // Client string too short - can't match

		return EFalse;

		}

	// Now let's run along the string

	for (TInt index = 0; index < pluginStringLength; index++)

		{

		const TUint8 pluginChar = aPluginString[index];

		if (pluginChar=='?') // just ignore a wildchar

			{

			continue;

			}

		if (aClientString[index] != pluginChar)

			{

			return EFalse;

			}

		// else we've matched expected byte, so keep going

		aBytesMatched += 1;

		}

	aBytesMatched += (aPluginString[0]=='?' && pluginStringLength==1);

	ASSERT(aBytesMatched>0); // if we get this far, must have matched something - since we no match string can't be empty

	return ETrue;

	}