// CHTTPFormEncoder.cpp

// Copyright (c) 2001-2009 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:

//

// System includes

#include <chttpformencoder.h> // Class signature

#include <httperr.h>

// Local includes

const TInt KFormEncoderBufferIncrementSize = 256;

EXPORT_C CHTTPFormEncoder* CHTTPFormEncoder::NewL()

	{

	CHTTPFormEncoder* self = new (ELeave) CHTTPFormEncoder();

	CleanupStack::PushL(self);

	self->ConstructL();

	CleanupStack::Pop(self);

	return self;

	}

EXPORT_C CHTTPFormEncoder::~CHTTPFormEncoder()

	{

	__ASSERT_DEBUG(iState != ESupplyingData,HTTPPanic::Panic(HTTPPanic::EHTTPFormDataUnreleased));

	delete iData;

	}

CHTTPFormEncoder::CHTTPFormEncoder() 

	{}

void CHTTPFormEncoder::ConstructL()

	{

	iData = HBufC8::NewL(KFormEncoderBufferIncrementSize);

	}

TBool CHTTPFormEncoder::GetNextDataPart(TPtrC8& aDataPart)

	{

	aDataPart.Set(*iData);

	iState = ESupplyingData;

	return ETrue;

	}

 void CHTTPFormEncoder::ReleaseData()

	{

	iState = EDataReleased;

	}

TInt CHTTPFormEncoder::OverallDataSize()

	{

	iState = ESuppliedSize;

	return iData->Size();

	}

TInt CHTTPFormEncoder::Reset()

	{

	return KErrNone;

	}

EXPORT_C void CHTTPFormEncoder::AddFieldL(const TDesC8& aFieldName, const TDesC8& aFieldValue)

	{

	__ASSERT_DEBUG(iState==EAllowAppendData, HTTPPanic::Panic(HTTPPanic::EHTTPFormSupplyingData));

	if (!aFieldName.Length())

		User::Leave(KErrArgument);

	// The maximum size is if every single character would have to be encoded as its hex equivalent. 

	// That is %HH. Also need to add room for the '=' and '&' field separator

	TInt reqSize = (aFieldName.Length() + aFieldValue.Length())*3 +2;

	if (!iData)

		iData = HBufC8::NewL(reqSize);

	else

		{

		TInt currentLength = iData->Length();

		if (reqSize + currentLength > iData->Des().MaxLength())

			{

			TInt amountToGrow = reqSize < KFormEncoderBufferIncrementSize? KFormEncoderBufferIncrementSize : reqSize;

			iData = iData->ReAllocL(amountToGrow+currentLength);

			}

		}

	if (iData->Length() >0)

		iData->Des().Append('&');

	AppendData(aFieldName);

	iData->Des().Append('=');

	AppendData(aFieldValue);

	}

TBool CHTTPFormEncoder::IsAlphaNumeric(TUint8 aChar)

	{

	return (aChar >= 'a' && aChar <= 'z') ||

		(aChar >= 'A' && aChar <= 'Z') ||

		(aChar >= '0' && aChar <='9');

	}

/** Appends a non alpha numeric character by converting it to %HH where HH is the Hexadecmial representation

of the character

*/

void CHTTPFormEncoder::AppendSpecialChar(TUint8 aChar)

	{

	TPtr8 dataPtr = iData->Des();

	dataPtr.Append('%');

	TUint hexChar = aChar/16;

	hexChar = hexChar > 9 ? hexChar + 55 : hexChar + 48;

	dataPtr.Append(hexChar);

	hexChar= aChar%16;

	hexChar = hexChar > 9 ? hexChar + 55 : hexChar + 48;

	dataPtr.Append(hexChar);

	}

void CHTTPFormEncoder::AppendData(const TDesC8& aData)

	{

	TBool hadCR  = EFalse;                                

	TInt length = aData.Length();

	for (TInt ii=0; ii<length; ++ii)

		{

		TPtr8 dataPtr = iData->Des();

		TUint8 charToProcess = aData[ii];

		if (charToProcess == 0x0d)	// turn CR into CR/LF

			{

			hadCR = ETrue;

			AppendSpecialChar(charToProcess);

			AppendSpecialChar(0x0a);

			continue;

			}

		if (hadCR)

			{

			hadCR = EFalse;

			if (charToProcess == 0x0a) // LF after a CR, so skip as already appended

				continue;

			}

		// handle spaces -> become +

		if (charToProcess == ' ')

			dataPtr.Append('+');

		// handle normal character

		else if (IsAlphaNumeric(charToProcess))

			dataPtr.Append((TChar)charToProcess);

		else 

			AppendSpecialChar(charToProcess); // encode to %HH

		//

		}

	}