/*

* Copyright (c) 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:

*

*/

using System;

using System.Collections.Generic;

using System.Text;

using SymbianUtils.SourceParser.Objects;

using SymbianUtils.SourceParser.Parsers;

namespace SymbianUtils.SourceParser.Parsers

{

    public class ParserSrcMethod

    {

        #region Constructors

        public ParserSrcMethod()

        {

        }

        #endregion

        #region API

        public SrcMethod Parse( ref string aText )

        {

            SrcMethod ret = null;

            //

            if ( aText.Length > 0 )

            {

                string parameters = string.Empty;

                //

                if ( ContainsParameters( aText ) )

                {

                    // This leaves modifiers intact

                    parameters = ExtractParameters( ref aText );

                }

                // Look for the class separator. If we find that, then everything after

                // it is the method name.

                //

                // If no class separator exists, then we treat the whole thing as the method

                // name.

                int pos = aText.IndexOf( SrcClass.KClassSeparator );

                // By default, treat the whole text as the class name

                string methodText = aText;

                if ( pos >= 0 )

                {

                    methodText = aText.Substring( pos + SrcClass.KClassSeparator.Length );

                    aText = aText.Substring( 0, pos + SrcClass.KClassSeparator.Length );

                }

                else

                {

                    // Everything was consumed...

                    aText = string.Empty;

                }

                // Make a new method. Work out if the method text

                // actually has any parameters

                ret = new SrcMethod();

                // Try to parse the modifiers. We extract that first

                // to leave us with just the method name and the parameters.

                bool hasModifier = ContainsModifier( methodText );

                if ( hasModifier )

                {

                    ParserSrcMethodModifier parser = new ParserSrcMethodModifier();

                    SrcMethodModifier modifier = parser.Parse( ref methodText );

                    if ( modifier != null )

                    {

                        ret.Modifier = modifier;

                    }

                }

                // Try to parse the parameters. We can also use this

                // to calculate the exact method name.

                if ( parameters.Length > 0 )

                {

                    ParserSrcMethodParameter parser = new ParserSrcMethodParameter();

                    parser.Parse( ref parameters, ret );

                }

                // What's left should be the method name followed by "()" if the

                // 'method' wasn't a label.

                if ( ContainsParameters( methodText ) )

                {

                    // Discard "()";

                    pos = methodText.LastIndexOf( "(" );

                    methodText = methodText.Substring( 0, pos );

                }

                ret.Name = methodText;

            }

            //

            return ret;

        }

        #endregion

        #region Properties

        #endregion

        #region Internal methods

        private static bool ContainsParameters( string aText )

        {

            // Search initiall for '(' - if that is found, then

            // we should also find a closing bracket.

            bool parameters = false;

            int openingBracketPos = aText.IndexOf( "(" );

            //

            if ( openingBracketPos > 0 )

            {

                // Should also be a closing bracket and it should

                // appear after the opening bracket

                int closingBracketPos = aText.LastIndexOf( ")" );

                parameters = ( closingBracketPos > openingBracketPos );

            }

            //

            return parameters;

        }

        private static bool ContainsModifier( string aText )

        {

            bool modifiers = false;

            int openingBracketPos = aText.IndexOf( "(" );

            if ( openingBracketPos >= 0 )

            {

                int closingBracketPos = openingBracketPos;

                SymbianUtils.Strings.StringParsingUtils.SkipToEndOfSection( ref aText, ref closingBracketPos, '(', ')' );

                if ( closingBracketPos > openingBracketPos )

                {

                    // everything here on is the modifier text;

                    string modifierText = aText.Substring( closingBracketPos + 1 );

                    modifiers = ( modifierText.Trim().Length > 0 );

                }

            }

            //

            return modifiers;

        }

        private static string ExtractParameters( ref string aText )

        {

            const string KOperatorChevronText = "operator <<";

            // DoAppendFormatList<TDes16, (int)2>(T1&, const T3&, std::__va_list, T2*)

            // DoAppendFormatList<TDes16, (int)2>(T1&, TBuf<(int)256>, std::__va_list, T2*)

            // Method<TDes16>::Wibble( something )

            // Method::Wibble( RPointerArray<HBufC> )

            // RTest::operator ()(int, int, const unsigned short*)

            // TDesC16::Left(int) const

            // CObjectCon::AtL(int) const

            // User::Panic(const TDesC16&, int)

            // operator <<(RWriteStream&, const unsigned char&)

            // Handle special case of "operator <<" confusing matters

            string workingText = aText;

            int operatorOpeningChevronPos = aText.IndexOf( KOperatorChevronText );

            if ( operatorOpeningChevronPos >= 0 )

            {

                aText = aText.Substring( 0, operatorOpeningChevronPos + KOperatorChevronText.Length );

                workingText = workingText.Substring( operatorOpeningChevronPos + KOperatorChevronText.Length );

            }

            else

            {

                aText = string.Empty;

            }

            string ret = string.Empty;

            //

            int closingPos = 0;

            int openingPos = 0;

            int templatePos = 0;

            //

            while ( openingPos >= 0 )

            {

                if ( templatePos >= 0 )

                    templatePos = workingText.IndexOf( "<", templatePos );

                openingPos = workingText.IndexOf( "(", openingPos );

                if ( templatePos >= 0 && templatePos < openingPos )

                {

                    // Template region appears before the next bracket. Skip

                    // over all characters until we hit the end of the template

                    // section

                    int endingPos = templatePos;

                    SymbianUtils.Strings.StringParsingUtils.SkipToEndOfSection( ref workingText, ref endingPos, '<', '>' );

                    if ( endingPos < 0 )

                    {

                        // Matching closing brace was never found - dealing with operator << ?

                        templatePos = -1;

                    }

                    else

                    {

                        // Something like DoAppendFormatList<TDes16, (int)2>(T1&, const T3&, std::__va_list, T2*) ???

                        templatePos = endingPos;

                        openingPos = endingPos;

                    }

                }

                else if ( openingPos >= 0 )

                {

                    // Skipped over any template nonsense. Work backward from the end 

                    // in order to locate start of parameters.

                    closingPos = workingText.LastIndexOf( ')' );

                    openingPos = closingPos;

                    SymbianUtils.Strings.StringParsingUtils.SkipToBeginningOfSection( ref workingText, ref openingPos, '(', ')' );

                    string parameters = workingText.Substring( openingPos + 1, ( closingPos - openingPos ) - 1 ).Trim();

                    ret = parameters;

                    workingText = workingText.Substring( 0, openingPos + 1 ) + workingText.Substring( closingPos );

                    aText = aText + workingText;

                    break;

                }

            }

            //

            return ret;

        }

        #endregion

        #region Data members

        #endregion

    }

}