# -*- encoding: utf-8 -*-
#
#
# Copyright (C) 2005-2011 Jörg Lehmann <joergl@users.sourceforge.net>
# Copyright (C) 2006-2011 Michael Schindler <m-schindler@users.sourceforge.net>
# Copyright (C) 2005-2011 André Wobst <wobsta@users.sourceforge.net>
#
# This file is part of PyX (http://pyx.sourceforge.net/).
#
# PyX is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# PyX is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with PyX; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA

import logging
from pyx import bbox, baseclasses, deco, path, pswriter, pdfwriter, svgwriter, trafo, unit
from . import t1file, afmfile

logger = logging.getLogger("pyx")

##############################################################################
# PS resources
##############################################################################

class PST1file(pswriter.PSresource):

    """ PostScript font definition included in the prolog """

    def __init__(self, t1file, glyphnames, charcodes):
        """ include type 1 font t1file stripped to the given glyphnames"""
        self.type = "t1file"
        self.t1file = t1file
        self.id = t1file.name
        self.glyphnames = set(glyphnames)
        self.charcodes = set(charcodes)

    def merge(self, other):
        self.glyphnames.update(other.glyphnames)
        self.charcodes.update(other.charcodes)

    def output(self, file, writer, registry):
        file.write("%%%%BeginFont: %s\n" % self.t1file.name)
        if writer.strip_fonts:
            if self.glyphnames:
                file.write("%%Included glyphs: %s\n" % " ".join(self.glyphnames))
            if self.charcodes:
                file.write("%%Included charcodes: %s\n" % " ".join([str(charcode) for charcode in self.charcodes]))
            self.t1file.getstrippedfont(self.glyphnames, self.charcodes).outputPS(file, writer)
        else:
            self.t1file.outputPS(file, writer)
        file.write("\n%%EndFont\n")


_ReEncodeFont = pswriter.PSdefinition("ReEncodeFont", b"""{
  5 dict
  begin
    /newencoding exch def
    /newfontname exch def
    /basefontname exch def
    /basefontdict basefontname findfont def
    /newfontdict basefontdict maxlength dict def
    basefontdict {
      exch dup dup /FID ne exch /Encoding ne and
      { exch newfontdict 3 1 roll put }
      { pop pop }
      ifelse
    } forall
    newfontdict /FontName newfontname put
    newfontdict /Encoding newencoding put
    newfontname newfontdict definefont pop
  end
}""")


class PSreencodefont(pswriter.PSresource):

    """ reencoded PostScript font"""

    def __init__(self, basefontname, newfontname, encoding):
        """ reencode the font """

        self.type = "reencodefont"
        self.basefontname = basefontname
        self.id = self.newfontname = newfontname
        self.encoding = encoding

    def output(self, file, writer, registry):
        file.write("%%%%BeginResource: %s\n" % self.newfontname)
        file.write("/%s /%s\n[" % (self.basefontname, self.newfontname))
        vector = [None] * len(self.encoding)
        for glyphname, charcode in list(self.encoding.items()):
            vector[charcode] = glyphname
        for i, glyphname in enumerate(vector):
            if i:
                if not (i % 8):
                    file.write("\n")
                else:
                    file.write(" ")
            file.write("/%s" % glyphname)
        file.write("]\n")
        file.write("ReEncodeFont\n")
        file.write("%%EndResource\n")


_ChangeFontMatrix = pswriter.PSdefinition("ChangeFontMatrix", b"""{
  5 dict
  begin
    /newfontmatrix exch def
    /newfontname exch def
    /basefontname exch def
    /basefontdict basefontname findfont def
    /newfontdict basefontdict maxlength dict def
    basefontdict {
      exch dup dup /FID ne exch /FontMatrix ne and
      { exch newfontdict 3 1 roll put }
      { pop pop }
      ifelse
    } forall
    newfontdict /FontName newfontname put
    newfontdict /FontMatrix newfontmatrix readonly put
    newfontname newfontdict definefont pop
  end
}""")


class PSchangefontmatrix(pswriter.PSresource):

    """ change font matrix of a PostScript font"""

    def __init__(self, basefontname, newfontname, newfontmatrix):
        """ change the font matrix """

        self.type = "changefontmatrix"
        self.basefontname = basefontname
        self.id = self.newfontname = newfontname
        self.newfontmatrix = newfontmatrix

    def output(self, file, writer, registry):
        file.write("%%%%BeginResource: %s\n" % self.newfontname)
        file.write("/%s /%s\n" % (self.basefontname, self.newfontname))
        file.write(str(self.newfontmatrix))
        file.write("\nChangeFontMatrix\n")
        file.write("%%EndResource\n")


##############################################################################
# PDF resources
##############################################################################

class PDFfont(pdfwriter.PDFobject):

    def __init__(self, fontname, basefontname, charcodes, fontdescriptor, encoding, metric):
        pdfwriter.PDFobject.__init__(self, "font", fontname)

        self.fontname = fontname
        self.basefontname = basefontname
        self.charcodes = set(charcodes)
        self.fontdescriptor = fontdescriptor
        self.encoding = encoding
        self.metric = metric

    def merge(self, other):
        self.charcodes.update(other.charcodes)

    def write(self, file, writer, registry):
        file.write("<<\n"
                   "/Type /Font\n"
                   "/Subtype /Type1\n")
        file.write("/Name /%s\n" % self.fontname)
        file.write("/BaseFont /%s\n" % self.basefontname)
        firstchar = min(self.charcodes)
        lastchar = max(self.charcodes)
        file.write("/FirstChar %d\n" % firstchar)
        file.write("/LastChar %d\n" % lastchar)
        file.write("/Widths\n"
                   "[")
        if self.encoding:
            encoding = self.encoding.getvector()
        else:
            if self.fontdescriptor.fontfile.t1file.encoding is None:
                self.fontdescriptor.fontfile.t1file._encoding()
            encoding = self.fontdescriptor.fontfile.t1file.encoding
        for i in range(firstchar, lastchar+1):
            if i:
                if not (i % 8):
                    file.write("\n")
                else:
                    file.write(" ")
            if i in self.charcodes:
                if self.metric is not None:
                    file.write("%i" % self.metric.width_ds(encoding[i]))
                else:
                    file.write("%i" % self.fontdescriptor.fontfile.t1file.getglyphinfo(encoding[i])[0])
            else:
                file.write("0")
        file.write(" ]\n")
        file.write("/FontDescriptor %d 0 R\n" % registry.getrefno(self.fontdescriptor))
        if self.encoding:
            file.write("/Encoding %d 0 R\n" % registry.getrefno(self.encoding))
        file.write(">>\n")


class PDFstdfont(pdfwriter.PDFobject):

    def __init__(self, basename):
        pdfwriter.PDFobject.__init__(self, "font", "stdfont-%s" % basename)
        self.name = basename # name is ignored by acroread
        self.basename = basename

    def write(self, file, writer, registry):
        file.write("<</BaseFont /%s\n" % self.basename)
        file.write("/Name /%s\n" % self.name)
        file.write("/Type /Font\n")
        file.write("/Subtype /Type1\n")
        file.write(">>\n")

# the 14 standard fonts that are always available in PDF
PDFTimesRoman           = PDFstdfont("Times-Roman")
PDFTimesBold            = PDFstdfont("Times-Bold")
PDFTimesItalic          = PDFstdfont("Times-Italic")
PDFTimesBoldItalic      = PDFstdfont("Times-BoldItalic")
PDFHelvetica            = PDFstdfont("Helvetica")
PDFHelveticaBold        = PDFstdfont("Helvetica-Bold")
PDFHelveticaOblique     = PDFstdfont("Helvetica-Oblique")
PDFHelveticaBoldOblique = PDFstdfont("Helvetica-BoldOblique")
PDFCourier              = PDFstdfont("Courier")
PDFCourierBold          = PDFstdfont("Courier-Bold")
PDFCourierOblique       = PDFstdfont("Courier-Oblique")
PDFCourierBoldOblique   = PDFstdfont("Courier-BoldOblique")
PDFSymbol               = PDFstdfont("Symbol")
PDFZapfDingbats         = PDFstdfont("ZapfDingbats")


class PDFfontdescriptor(pdfwriter.PDFobject):

    def __init__(self, fontname, fontfile, metric):
        pdfwriter.PDFobject.__init__(self, "fontdescriptor", fontname)
        self.fontname = fontname
        self.fontfile = fontfile
        self.metric = metric

    def write(self, file, writer, registry):
        file.write("<<\n"
                   "/Type /FontDescriptor\n"
                   "/FontName /%s\n" % self.fontname)
        if self.metric is not None:
            self.metric.writePDFfontinfo(file)
        else:
            self.fontfile.t1file.writePDFfontinfo(file)
        if self.fontfile is not None:
            file.write("/FontFile %d 0 R\n" % registry.getrefno(self.fontfile))
        file.write(">>\n")


class PDFfontfile(pdfwriter.PDFobject):

    def __init__(self, t1file, glyphnames, charcodes):
        pdfwriter.PDFobject.__init__(self, "fontfile", t1file.name)
        self.t1file = t1file
        self.glyphnames = set(glyphnames)
        self.charcodes = set(charcodes)

    def merge(self, other):
        self.glyphnames.update(other.glyphnames)
        self.charcodes.update(other.charcodes)

    def write(self, file, writer, registry):
        if writer.strip_fonts:
            self.t1file.getstrippedfont(self.glyphnames, self.charcodes).outputPDF(file, writer)
        else:
            self.t1file.outputPDF(file, writer)


class PDFencoding(pdfwriter.PDFobject):

    def __init__(self, encoding, name):
        pdfwriter.PDFobject.__init__(self, "encoding", name)
        self.encoding = encoding

    def getvector(self):
        # As self.encoding might be appended after the constructur has set it,
        # we need to defer the calculation until the whole content was constructed.
        vector = [None] * len(self.encoding)
        for glyphname, charcode in list(self.encoding.items()):
            vector[charcode] = glyphname
        return vector

    def write(self, file, writer, registry):
        file.write("<<\n"
                   "/Type /Encoding\n"
                   "/Differences\n"
                   "[0")
        for i, glyphname in enumerate(self.getvector()):
            if i:
                if not (i % 8):
                    file.write("\n")
                else:
                    file.write(" ")
            file.write("/%s" % glyphname)
        file.write("]\n"
                   ">>\n")


##############################################################################
# SVG resources
##############################################################################


_glyphnames = {glyphname: str for str, glyphname in afmfile.unicodestring.items()}
_charcodes = {i: chr(i) for i in range(32, 127)} # 0x20 (space) to 0x7e (tilde)


class SVGT1mapping:

    def __init__(self, glyphnames, charcodes):
        # glyphnames and charcodes are not stored as sets, but are dicts
        # mapping the values to unicode characters. If the glyphnames and
        # charcodes are contained in _glyphnames and _charcodes, use those
        # values, otherwise use the private use areas A and B.
        self.private_glyphname = 0xf0000
        self.private_charcode = 0x100000
        self.glyphnames = {}
        self.charcodes = {}
        self.merge_glyphnames(glyphnames)
        self.merge_charcodes(charcodes)

    def merge_glyphnames(self, glyphnames):
        for glyphname in glyphnames:
            if glyphname not in self.glyphnames:
                if glyphname in _glyphnames:
                    self.glyphnames[glyphname] = _glyphnames[glyphname]
                else:
                    self.glyphnames[glyphname] = chr(self.private_glyphname)
                    self.private_glyphname += 1

    def merge_charcodes(self, charcodes):
        for charcode in charcodes:
            if charcode not in self.charcodes:
                if charcode in _charcodes:
                    self.charcodes[charcode] = _charcodes[charcode]
                else:
                    self.charcodes[charcode] = chr(self.private_charcode)
                    self.private_charcode += 1


class SVGT1file(svgwriter.SVGresource, SVGT1mapping):

    """ PostScript font definition included in the prolog """

    def __init__(self, t1file, glyphnames, charcodes):
        """ include type 1 font t1file stripped to the given glyphnames"""
        self.t1file = t1file
        svgwriter.SVGresource.__init__(self, "t1file", t1file.name)
        SVGT1mapping.__init__(self, glyphnames, charcodes)

    def merge(self, other):
        # Note that merging the glyphnames and charcodes does not alter
        # any existing mapping to the private use areas for self (but for
        # other). If you merge before use, the mapping by self.glyphnames
        # and self.charcodes is already updated and also copied to "other".
        self.merge_glyphnames(other.glyphnames.keys())
        self.merge_charcodes(other.charcodes.keys())
        other.glyphnames = self.glyphnames
        other.charcodes = self.charcodes

    def output(self, xml, writer, registry):
        xml.startSVGElement("font", {})
        xml.startSVGElement("font-face", {"font-family": self.t1file.name})
        xml.endSVGElement("font-face")
        for glyphname in self.glyphnames:
            glyphpath = self.t1file.getglyphpath_pt(0, 0, glyphname, 1000, convertcharcode=False)
            attrs = {"unicode": self.glyphnames[glyphname],
                     "horiz-adv-x": "%f" % glyphpath.wx_pt,
                     "d": glyphpath.path.returnSVGdata(inverse_y=False)}
            xml.startSVGElement("glyph", attrs)
            xml.endSVGElement("glyph")
        for charcode in self.charcodes:
            glyphpath = self.t1file.getglyphpath_pt(0, 0, charcode, 1000, convertcharcode=True)
            attrs = {"unicode": self.charcodes[charcode],
                     "horiz-adv-x": "%f" % glyphpath.wx_pt,
                     "d": glyphpath.path.returnSVGdata(inverse_y=False)}
            xml.startSVGElement("glyph", attrs)
            xml.endSVGElement("glyph")
        xml.endSVGElement("font")


##############################################################################
# basic PyX text output
##############################################################################

class font:

    def text(self, x, y, charcodes, size_pt, **kwargs):
        return self.text_pt(unit.topt(x), unit.topt(y), charcodes, size_pt, **kwargs)


class T1font(font):

    def __init__(self, t1file, metric=None):
        self.t1file = t1file
        self.name = t1file.name
        self.metric = metric

    def text_pt(self, x, y, charcodes, size_pt, **kwargs):
        return T1text_pt(self, x, y, charcodes, size_pt, **kwargs)


class T1builtinfont(T1font):

    def __init__(self, name, metric):
        self.name = name
        self.t1file = None
        self.metric = metric


class selectedfont:

    def __init__(self, name, size_pt):
        self.name = name
        self.size_pt = size_pt

    def __ne__(self, other):
        return self.name != other.name or self.size_pt != other.size_pt

    def outputPS(self, file, writer):
        file.write("/%s %f selectfont\n" % (self.name, self.size_pt))

    def outputPDF(self, file, writer):
        file.write("/%s %f Tf\n" % (self.name, self.size_pt))


class text_pt(baseclasses.canvasitem):

    def requiretextregion(self):
        return True


class T1text_pt(text_pt):

    def __init__(self, font, x_pt, y_pt, charcodes, size_pt, decoding=afmfile.unicodestring, slant=None, ignorebbox=False, kerning=False, ligatures=False, spaced_pt=0):
        if decoding is not None:
            self.glyphnames = [decoding[character] for character in charcodes]
            self.decode = True
        else:
            self.charcodes = charcodes
            self.decode = False
        self.font = font
        self.x_pt = x_pt
        self.y_pt = y_pt
        self.size_pt = size_pt
        self.slant = slant
        self.ignorebbox = ignorebbox
        self.kerning = kerning
        self.ligatures = ligatures
        self.spaced_pt = spaced_pt
        self._textpath = None

        if self.kerning and not self.decode:
            raise ValueError("decoding required for font metric access (kerning)")
        if self.ligatures and not self.decode:
            raise ValueError("decoding required for font metric access (ligatures)")
        if self.ligatures:
            self.glyphnames = self.font.metric.resolveligatures(self.glyphnames)

    def bbox(self):
        if self.font.metric is None:
            logger.warning("We are about to extract the bounding box from the path of the text. This is slow and differs from the font metric information. You should provide an afm file whenever possible.")
            return self.textpath().bbox()
        if not self.decode:
            raise ValueError("decoding required for font metric access (bbox)")
        if self.kerning:
            kerning_correction = sum(value or 0 for i, value in enumerate(self.font.metric.resolvekernings(self.glyphnames, self.size_pt)) if i%2)
        else:
            kerning_correction = 0
        return bbox.bbox_pt(self.x_pt,
                            self.y_pt+self.font.metric.depth_pt(self.glyphnames, self.size_pt),
                            self.x_pt+self.font.metric.width_pt(self.glyphnames, self.size_pt) + (len(self.glyphnames)-1)*self.spaced_pt + kerning_correction,
                            self.y_pt+self.font.metric.height_pt(self.glyphnames, self.size_pt))

    def getencodingname(self, encodings):
        """returns the name of the encoding (in encodings) mapping self.glyphnames to codepoints
        If no such encoding can be found or extended, a new encoding is added to encodings
        """
        glyphnames = set(self.glyphnames)
        if len(glyphnames) > 256:
            raise ValueError("glyphs do not fit into one single encoding")
        for encodingname, encoding in list(encodings.items()):
            glyphsmissing = []
            for glyphname in glyphnames:
                if glyphname not in list(encoding.keys()):
                    glyphsmissing.append(glyphname)

            if len(glyphsmissing) + len(encoding) < 256:
                # new glyphs fit in existing encoding which will thus be extended
                for glyphname in glyphsmissing:
                    encoding[glyphname] = len(encoding)
                return encodingname
        # create a new encoding for the glyphnames
        encodingname = "encoding%d" % len(encodings)
        encodings[encodingname] = dict([(glyphname, i) for i, glyphname in enumerate(glyphnames)])
        return encodingname

    def textpath(self):
        if self._textpath is None:
            if self.decode:
                if self.kerning:
                    data = self.font.metric.resolvekernings(self.glyphnames, self.size_pt)
                else:
                    data = self.glyphnames
            else:
                data = self.charcodes
            self._textpath = path.path()
            x_pt = self.x_pt
            y_pt = self.y_pt
            for i, value in enumerate(data):
                if self.kerning and i % 2:
                    if value is not None:
                        x_pt += value
                else:
                    if i:
                        x_pt += self.spaced_pt
                    glyphpath = self.font.t1file.getglyphpath_pt(x_pt, y_pt, value, self.size_pt, convertcharcode=not self.decode)
                    self._textpath += glyphpath.path
                    x_pt += glyphpath.wx_pt
                    y_pt += glyphpath.wy_pt
        return self._textpath

    def processPS(self, file, writer, context, registry, bbox):
        if not self.ignorebbox:
            bbox += self.bbox()

        if writer.text_as_path and not self.font.t1file:
            logger.warning("Cannot output text as path when font not given by a font file (like for builtin fonts).")
        if writer.text_as_path and self.font.t1file:
            deco.decoratedpath(self.textpath(), fillstyles=[]).processPS(file, writer, context, registry, bbox)
        else:
            # register resources
            if self.font.t1file is not None:
                if self.decode:
                    registry.add(PST1file(self.font.t1file, self.glyphnames, []))
                else:
                    registry.add(PST1file(self.font.t1file, [], self.charcodes))

            fontname = self.font.name
            if self.decode:
                encodingname = self.getencodingname(writer.encodings.setdefault(self.font.name, {}))
                encoding = writer.encodings[self.font.name][encodingname]
                newfontname = "%s-%s" % (fontname, encodingname)
                registry.add(_ReEncodeFont)
                registry.add(PSreencodefont(fontname, newfontname, encoding))
                fontname = newfontname

            if self.slant:
                newfontmatrix = trafo.trafo_pt(matrix=((1, self.slant), (0, 1)))
                if self.font.t1file is not None:
                    newfontmatrix = newfontmatrix * self.font.t1file.fontmatrix
                newfontname = "%s-slant%f" % (fontname, self.slant)
                registry.add(_ChangeFontMatrix)
                registry.add(PSchangefontmatrix(fontname, newfontname, newfontmatrix))
                fontname = newfontname

            # select font if necessary
            sf = selectedfont(fontname, self.size_pt)
            if context.selectedfont is None or sf != context.selectedfont:
                context.selectedfont = sf
                sf.outputPS(file, writer)

            file.write("%f %f moveto (" % (self.x_pt, self.y_pt))
            if self.decode:
                if self.kerning:
                    data = self.font.metric.resolvekernings(self.glyphnames, self.size_pt)
                else:
                    data = self.glyphnames
            else:
                data = self.charcodes
            for i, value in enumerate(data):
                if self.kerning and i % 2:
                    if value is not None:
                        file.write(") show\n%f 0 rmoveto (" % (value+self.spaced_pt))
                    elif self.spaced_pt:
                        file.write(") show\n%f 0 rmoveto (" % self.spaced_pt)
                else:
                    if i and not self.kerning and self.spaced_pt:
                        file.write(") show\n%f 0 rmoveto (" % self.spaced_pt)
                    if self.decode:
                        value = encoding[value]
                    if 32 < value < 127 and chr(value) not in "()[]<>\\":
                        file.write("%s" % chr(value))
                    else:
                        file.write("\\%03o" % value)
            file.write(") show\n")

    def processPDF(self, file, writer, context, registry, bbox):
        if not self.ignorebbox:
            bbox += self.bbox()

        if writer.text_as_path and not self.font.t1file:
            logger.warning("Cannot output text as path when font not given by a font file (like for builtin fonts).")
        if writer.text_as_path and self.font.t1file:
            deco.decoratedpath(self.textpath(), fillstyles=[]).processPDF(file, writer, context, registry, bbox)
        else:
            if self.decode:
                encodingname = self.getencodingname(writer.encodings.setdefault(self.font.name, {}))
                encoding = writer.encodings[self.font.name][encodingname]
                charcodes = [encoding[glyphname] for glyphname in self.glyphnames]
            else:
                charcodes = self.charcodes

            # create resources
            fontname = self.font.name
            if self.decode:
                newfontname = "%s-%s" % (fontname, encodingname)
                _encoding = PDFencoding(encoding, newfontname)
                fontname = newfontname
            else:
                _encoding = None
            if self.font.t1file is not None:
                if self.decode:
                    fontfile = PDFfontfile(self.font.t1file, self.glyphnames, [])
                else:
                    fontfile = PDFfontfile(self.font.t1file, [], self.charcodes)
            else:
                fontfile = None
            fontdescriptor = PDFfontdescriptor(self.font.name, fontfile, self.font.metric)
            font = PDFfont(fontname, self.font.name, charcodes, fontdescriptor, _encoding, self.font.metric)

            # register resources
            if fontfile is not None:
                registry.add(fontfile)
            registry.add(fontdescriptor)
            if _encoding is not None:
                registry.add(_encoding)
            registry.add(font)

            registry.addresource("Font", fontname, font, procset="Text")

            if self.slant is None:
                slantvalue = 0
            else:
                slantvalue = self.slant

            # select font if necessary
            sf = selectedfont(fontname, self.size_pt)
            if context.selectedfont is None or sf != context.selectedfont:
                context.selectedfont = sf
                sf.outputPDF(file, writer)

            # convert inter-character spacing to font units
            spaced = self.spaced_pt*1000/self.size_pt

            if self.kerning or spaced:
                file.write("1 0 %f 1 %f %f Tm [(" % (slantvalue, self.x_pt, self.y_pt))
            else:
                file.write("1 0 %f 1 %f %f Tm (" % (slantvalue, self.x_pt, self.y_pt))
            if self.decode:
                if self.kerning:
                    data = self.font.metric.resolvekernings(self.glyphnames)
                else:
                    data = self.glyphnames
            else:
                data = self.charcodes

            for i, value in enumerate(data):
                if self.kerning and i % 2:
                    if value is not None:
                        file.write(")%f(" % (-value-spaced))
                    elif spaced:
                        file.write(")%f(" % (-spaced))
                else:
                    if i and not self.kerning and spaced:
                        file.write(")%f(" % (-spaced))
                    if self.decode:
                        value = encoding[value]
                    if 32 <= value <= 127 and chr(value) not in "()[]<>\\":
                        file.write("%s" % chr(value))
                    else:
                        file.write("\\%03o" % value)
            if self.kerning or spaced:
                file.write(")] TJ\n")
            else:
                file.write(") Tj\n")

    def processSVG(self, xml, writer, context, registry, bbox):
        if not self.ignorebbox:
            bbox += self.bbox()

        # this is too common to be warned about as text_as_path is the
        # default for svg due to the missing font support by current browsers
        #
        # if writer.text_as_path and not self.font.t1file:
        #     logger.warning("Cannot output text as path when font not given by a font file (like for builtin fonts).")

        if writer.text_as_path and self.font.t1file:
            deco.decoratedpath(self.textpath(), fillstyles=[]).processSVG(xml, writer, context, registry, bbox)
        else:
            if self.font.t1file is not None:
                if self.decode:
                    t1mapping = SVGT1file(self.font.t1file, self.glyphnames, [])
                else:
                    t1mapping = SVGT1file(self.font.t1file, [], self.charcodes)
                registry.add(t1mapping)
            else:
                if self.decode:
                    t1mapping = SVGT1mapping(self.glyphnames, [])
                else:
                    t1mapping = SVGT1mapping([], self.charcodes)

            fontname = self.font.name

            if self.decode:
                if self.kerning:
                    data = self.font.metric.resolvekernings(self.glyphnames, self.size_pt)
                else:
                    data = self.glyphnames
            else:
                data = self.charcodes
            attrs = {"x": "%f" % self.x_pt,
                     "y": "%f" % -self.y_pt,
                     "font-size": "%f" % self.size_pt,
                     "font-family": fontname,
                     "fill": context.fillcolor}
            if context.fillopacity:
                attrs["opacity"] = "%f" % context.fillopacity
            if self.slant:
                trafo.trafo_pt(matrix=((1, self.slant), (0, 1))).outputSVGattrs(attrs, writer, context, registry)
            xml.startSVGElement("text", attrs)
            tspan = False
            for i, value in enumerate(data):
                if self.kerning and i % 2:
                    if value is not None:
                        if tspan:
                            xml.endSVGElement("tspan")
                        xml.startSVGElement("tspan", {"dx": "%f" % (value + self.spaced_pt)})
                        tspan = True
                    elif self.spaced_pt:
                        if tspan:
                            xml.endSVGElement("tspan")
                        xml.startSVGElement("tspan", {"dx": "%f" % (self.spaced_pt)})
                        tspan = True
                else:
                    if i and not self.kerning and self.spaced_pt:
                        if tspan:
                            xml.endSVGElement("tspan")
                        xml.startSVGElement("tspan", {"dx": "%f" % (self.spaced_pt)})
                        tspan = True
                    if self.decode:
                        xml.characters(t1mapping.glyphnames[value])
                    else:
                        xml.characters(t1mapping.charcodes[value])
            if tspan:
                xml.endSVGElement("tspan")
            xml.endSVGElement("text")
