/*

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

* All rights reserved.

*

* Redistribution and use in source and binary forms, with or without

* modification, are permitted provided that the following conditions are met:

*

* - Redistributions of source code must retain the above copyright notice,

*   this list of conditions and the following disclaimer.

* - Redistributions in binary form must reproduce the above copyright notice,

*   this list of conditions and the following disclaimer in the documentation

*   and/or other materials provided with the distribution.

* - Neither the name of Nokia Corporation nor the names of its contributors

*   may be used to endorse or promote products derived from this software

*   without specific prior written permission.

*

* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"

* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE

* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR

* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF

* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS

* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN

* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)

* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE

* POSSIBILITY OF SUCH DAMAGE.

* 

* Initial Contributors:

* Nokia Corporation - initial contribution.

*

* Contributors:

*

* Description: 

*

*/

using System;

using System.Collections.Generic;

using System.Text;

using SymbianUtils.RawItems;

using HeapLib.Statistics;

namespace HeapLib.Cells.Descriptors.Implementations.Unicode

{

    internal class DesUnicodeAlgorithmBase : DescriptorAlgorithmBase

    {

        #region Constructors & destructor

        public DesUnicodeAlgorithmBase( HeapStatistics aStats )

            : base( aStats )

        {

        }

        #endregion

        #region Internal constants

        protected const int KDescriptorRawItemOffsetEBufC = KDescriptorRawItemOffsetAfterLengthAndType + 1; // Allows for [Type+Length] + MaxLength

        #endregion

        #region Internal methods

        protected string ConvertToText( int aLengthInUnicodeChars )

        {

            return ConvertToText( aLengthInUnicodeChars, KDescriptorRawItemOffsetAfterLengthAndType );

        }

        protected string ConvertToText( int aLengthInUnicodeChars, int aStartRawItemIndex )

        {

            StringBuilder text = new StringBuilder();

            for ( int i = aStartRawItemIndex; i < RawItems.Count && i < Math.Min( aLengthInUnicodeChars, DescriptorAlgorithmBase.KDescriptorTextMaxLength ); i++ )

            {

                RawItem item = RawItems[ i ];

                //

                text.Append( item.OriginalCharacterisedDataAsUnicode );

            }

            //

            string ret = text.ToString();

            if ( ret.Length > aLengthInUnicodeChars )

            {

                ret = ret.Substring( 0, aLengthInUnicodeChars );

            }

            return ret;

        }

        protected int PrintableCharacterCount( int aMaxNumberOfUnicodeWordsToProcess, out bool aAllWordsWereAsciiCharacters )

        {

            return PrintableCharacterCount( aMaxNumberOfUnicodeWordsToProcess, KDescriptorRawItemOffsetAfterLengthAndType, out aAllWordsWereAsciiCharacters );

        }

        protected int PrintableCharacterCount( int aMaxNumberOfUnicodeWordsToProcess, int aStartRawItemIndex, out bool aAllWordsWereAsciiCharacters )

        {

            int printableCharCount = 0;

            int wordsRemaining = aMaxNumberOfUnicodeWordsToProcess;

            for ( int i = aStartRawItemIndex; i < RawItems.Count && wordsRemaining > 0; i++ )

            {

                RawItem item = RawItems[ i ];

                ushort[] data = item.DataArrayWords;

                //

                bool word1IsPrint = IsPrintableAsciiCharacter( data[ 0 ] );

                if ( word1IsPrint )

                {

                    ++printableCharCount;

                }

                --wordsRemaining;

                //

                if ( wordsRemaining > 0 )

                {

                    bool word2IsPrint = IsPrintableAsciiCharacter( data[ 1 ] );

                    if ( word2IsPrint )

                    {

                        ++printableCharCount;

                    }

                    --wordsRemaining;

                }

            }

            //

            aAllWordsWereAsciiCharacters = ( aMaxNumberOfUnicodeWordsToProcess == printableCharCount );

            return printableCharCount;

        }

        protected static bool IsPrintableAsciiCharacter( ushort aWord )

        {

            bool ret = false;

            //

            if ( aWord >= 32 /*SPACE*/ && aWord < 127 /*DEL*/ || aWord == 0x0D /*CR*/ || aWord == 0x0A /*LF*/ || aWord == 0x09 /*TAB*/ )

            {

                ret = true;

            }

            //

            return ret;

        }

        #endregion

    }

}