/*
 *  catch_xmlwriter.hpp
 *  Catch
 *
 *  Created by Phil on 09/12/2010.
 *  Copyright 2010 Two Blue Cubes Ltd. All rights reserved.
 *
 *  Distributed under the Boost Software License, Version 1.0. (See accompanying
 *  file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
 */
#ifndef TWOBLUECUBES_CATCH_XMLWRITER_HPP_INCLUDED
#define TWOBLUECUBES_CATCH_XMLWRITER_HPP_INCLUDED

namespace Catch
{
    class XmlWriter
    {
    public:
        
        class ScopedElement
        {
        public:
            ScopedElement( XmlWriter* writer )
            :   m_writer( writer )
            {
            }
            
            ScopedElement( const ScopedElement& other )
            :   m_writer( other.m_writer )
            {
                other.m_writer = NULL;
            }
            
            ~ScopedElement()
            {
                if( m_writer )
                    m_writer->endElement();
            }

            ScopedElement& writeText( const std::string& text )
            {
                m_writer->writeText( text );
                return *this;
            }
            
        private:
            mutable XmlWriter* m_writer;
        };
        
        XmlWriter( std::ostream& os)
        :   m_tagIsOpen( false ),
            m_needsNewline( false ),
            m_os( os )
        {
        }
        
        ~XmlWriter()
        {
            while( !m_tags.empty() )
            {
                endElement();
            }
        }
        
        XmlWriter& startElement( const std::string& name )
        {
            ensureTagClosed();
            newlineIfNecessary();
            m_os << m_indent << "<" << name;
            m_tags.push_back( name );
            m_indent += "  ";
            m_tagIsOpen = true;
            return *this;
        }

        ScopedElement scopedElement( const std::string& name )
        {
            ScopedElement scoped( this );
            startElement( name );
            return scoped;
        }

        XmlWriter& endElement()
        {
            newlineIfNecessary();
            m_indent = m_indent.substr( 0, m_indent.size()-2 );
            if( m_tagIsOpen )
            {
                m_os << "/>\n";
                m_tagIsOpen = false;
            }
            else
            {
                m_os << m_indent << "</" << m_tags.back() << ">\n";
            } 
            m_tags.pop_back();
            return *this;
        }
        
        XmlWriter& writeAttribute( const std::string& name, const std::string& attribute )
        {
            if( !name.empty() && !attribute.empty() )
            {
                m_os << " " << name << "=\"";
                writeEncodedText( attribute );
                m_os << "\"";
            }
            return *this;
        }
        
        template<typename T>
        XmlWriter& writeAttribute( const std::string& name, const T& attribute )
        {
            if( !name.empty() )
            {
                m_os << " " << name << "=\"" << attribute << "\"";
            }
            return *this;
        }
        
        XmlWriter& writeText( const std::string& text )
        {
            if( !text.empty() )
            {
                bool tagWasOpen = m_tagIsOpen;
                ensureTagClosed();
                if( tagWasOpen )
                    m_os << m_indent;
                writeEncodedText( text );
                m_needsNewline = true;
            }
            return *this;
        }
        
        XmlWriter& writeComment( const std::string& text )
        {
            ensureTagClosed();
            m_os << m_indent << "<!--" << text << "-->";
            m_needsNewline = true;
            return *this;
        }
        
        XmlWriter& writeBlankLine()
        {
            ensureTagClosed();
            m_os << "\n";
            return *this;
        }
        
    private:
        
        void ensureTagClosed()
        {
            if( m_tagIsOpen )
            {
                m_os << ">\n";
                m_tagIsOpen = false;
            }
        }
        
        void newlineIfNecessary()
        {
            if( m_needsNewline )
            {
                m_os << "\n";
                m_needsNewline = false;
            }
        }
        
        void writeEncodedText( const std::string& text )
        {
            // !TBD finish this
            if( !findReplaceableString( text, "<", "&lt;" ) &&
               !findReplaceableString( text, "&", "&amp;" ) &&
               !findReplaceableString( text, "\"", "&quote;" ) )
            {
                m_os << text;
            }
        }
        
        bool findReplaceableString( const std::string& text, const std::string& replaceWhat, const std::string& replaceWith )
        {
            std::string::size_type pos = text.find_first_of( replaceWhat );
            if( pos != std::string::npos )
            {
                m_os << text.substr( 0, pos ) << replaceWith;
                writeEncodedText( text.substr( pos+1 ) );
                return true;
            }
            return false;
        }
        
        bool m_tagIsOpen;
        bool m_needsNewline;
        std::vector<std::string> m_tags;
        std::string m_indent;
        std::ostream& m_os;
    };
    
}
#endif