/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
 * This file is part of the LibreOffice project.
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 */

#include "units.hxx"
#include <basegfx/range/b2drange.hxx>
#include <gfxtypes.hxx>
#include <rtl/ustring.hxx>
#include <boost/spirit/include/classic.hpp>

namespace svgi
{

double convLength( const OUString& value, SvgUnit unit, const State& rState, char dir )
{
    // convert svg unit to internal coordinates ("pixel"). Since the
    // OOo drawing layer is still largely integer-based, the initial
    // viewport transformation includes a certain scale factor
    double fRet(value.toDouble());
    switch ( unit )
    {
        case SVG_LENGTH_UNIT_CM: fRet *= F_SVG_PIXEL_PER_INCH/2.54; break;
        case SVG_LENGTH_UNIT_IN: fRet *= F_SVG_PIXEL_PER_INCH; break;
        case SVG_LENGTH_UNIT_MM: fRet *= F_SVG_PIXEL_PER_INCH/25.4; break;
        case SVG_LENGTH_UNIT_PC: fRet *= F_SVG_PIXEL_PER_INCH/6.0; break;
        case SVG_LENGTH_UNIT_PT: fRet *= F_SVG_PIXEL_PER_INCH/72.0; break;
        case SVG_LENGTH_UNIT_EM: fRet *= rState.mnFontSize; break;
        case SVG_LENGTH_UNIT_EX: fRet *= rState.mnFontSize / 2.0; break;
        case SVG_LENGTH_UNIT_USER:
        case SVG_LENGTH_UNIT_PX:
            // no unit defaults to PX in svg, assume display to have 90DPI
            break;
        case SVG_LENGTH_FONT_SIZE:
        {
            //In CSS2, the suggested scaling factor between adjacent indexes is 1.2
            if ( value == "xx-small" )
                fRet = rState.mnFontSize / 1.728;
            else if ( value == "x-small" )
                fRet = rState.mnFontSize / 1.44;
            else if ( value == "small" )
                fRet = rState.mnFontSize / 1.2;
            else if ( value == "smaller" )
                fRet = rState.mnParentFontSize / 1.2;
            else if ( value == "initial" || value == "medium" )
                fRet = rState.mnFontSize;
            else if ( value == "larger" )
                fRet = rState.mnParentFontSize * 1.2;
            else if ( value == "large" )
                fRet = rState.mnFontSize * 1.2;
            else if ( value == "x-large" )
                fRet = rState.mnFontSize * 1.44;
            else if ( value == "xx-large" )
                fRet = rState.mnFontSize * 1.728;

            break;
        }
        case SVG_LENGTH_UNIT_PERCENTAGE:
        {
            double fBoxLen;
            if (rState.maViewBox.isEmpty())
            {
                basegfx::B2DRange aDefaultBox(0, 0,
                  convLength("210", SVG_LENGTH_UNIT_MM, rState, 'h'),
                  convLength("297", SVG_LENGTH_UNIT_MM, rState, 'v'));
                fBoxLen = (dir=='h' ? aDefaultBox.getWidth() :
                          (dir=='v' ? aDefaultBox.getHeight() :
                           aDefaultBox.getRange().getLength()));
            }
            else
            {
                fBoxLen = (dir=='h' ? rState.maViewBox.getWidth() :
                          (dir=='v' ? rState.maViewBox.getHeight() :
                           rState.maViewBox.getRange().getLength()));
            }

            fRet *= fBoxLen/100.0;
        }
        break;
        default: SAL_WARN("filter.svg", "Unknown length type" ); break;
    }

    return fRet;
}

double convLength( const OUString& sValue, const State& rState, char dir )
{
    //FIXME: convert deprecated spirit::classic to use spirit::qi
    using namespace ::boost::spirit::classic;

    OString aUTF8 = OUStringToOString( sValue,
                                                 RTL_TEXTENCODING_UTF8 );

    std::string sVal;
    SvgUnit eUnit=SVG_LENGTH_UNIT_PX;
    const bool bRes = parse(aUTF8.getStr(),
        //  Begin grammar
        (
            //parse font-size keywords (ie: xx-large, medium )
            ( +alpha_p >> !(str_p("-") >> +alpha_p) )[assign_a(sVal)]
                >> str_p("")[assign_a(eUnit,SVG_LENGTH_FONT_SIZE)] |
            //take the first part and ignore the units
            ( +(anychar_p -
             (str_p("cm") |
             str_p("em") |
             str_p("ex") |
             str_p("in") |
             str_p("mm") |
             str_p("pc") |
             str_p("pt") |
             str_p("px") |
             str_p("%")))
            )[assign_a(sVal)]
            >> (  str_p("cm") [assign_a(eUnit,SVG_LENGTH_UNIT_CM)]
                | str_p("em") [assign_a(eUnit,SVG_LENGTH_UNIT_EM)]
                | str_p("ex") [assign_a(eUnit,SVG_LENGTH_UNIT_EX)]
                | str_p("in") [assign_a(eUnit,SVG_LENGTH_UNIT_IN)]
                | str_p("mm") [assign_a(eUnit,SVG_LENGTH_UNIT_MM)]
                | str_p("pc") [assign_a(eUnit,SVG_LENGTH_UNIT_PC)]
                | str_p("pt") [assign_a(eUnit,SVG_LENGTH_UNIT_PT)]
                | str_p("px") [assign_a(eUnit,SVG_LENGTH_UNIT_PX)]
                | str_p("%") [assign_a(eUnit,SVG_LENGTH_UNIT_PERCENTAGE)]
                | str_p("") [assign_a(eUnit,SVG_LENGTH_UNIT_USER)]
                | end_p)
        ),
        //  End grammar
        space_p).full;

    if( !bRes )
        return 0.0;

    OUString oVal = OUString::createFromAscii(sVal.c_str()).replaceAll(",",".");

    return convLength(oVal,eUnit,rState,dir);
}

} // namespace svgi

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