#!/usr/bin/python3

# -*- coding: utf-8 -*-

# Time-stamp: <2008-06-23 22:21:26 ah>

"""

Provide an encoder for a font specification configuration: the encoder is fed

with Unicode characters one by one and determines the needed font switches

between the preceding and the current character.

"""

import re

import xml.dom.minidom

import logging

from dbtexmf.dblatex.xetex.fcfallback import FcFallbackFontSpec, DefaultFontSpec

from dbtexmf.dblatex.xetex.fontspec import FontSpec, _indent

class FontSpecConfig:

    """

    This object parses an XML fontspec configuration file and build the

    resulting fontspec tree, the root fontspec being the default font

    to apply.

    The fontspec configuration file defines the fonts to apply in order

    of precedence (and for some Unicode ranges) and the font levels (or

    subfonts) thanks to the 'refmode' attribute that links a font to its

    parent.

    """

    def __init__(self, conf_file):

        """Create a font specification configuration from the specified file

        (file name or file-like object).

        """

        self.log = logging.getLogger("dblatex")

        self.fontspecs = []

        self.fontnames = {}

        dom_document = xml.dom.minidom.parse(conf_file)

        for dom_fontspec in dom_document.getElementsByTagName('fontspec'):

            default = dom_fontspec.getAttribute('default')

            if default:

                self.log.debug("has default")

                fallback = dom_fontspec.getAttribute('fallback')

                if fallback == "fontconfig":

                    self.default_fontspec = FcFallbackFontSpec()

                else:

                    self.default_fontspec = DefaultFontSpec()

                fontspec = self.default_fontspec

            else:

                fontspec = FontSpec()

            fontspec.fromnode(dom_fontspec)

            if fontspec != self.default_fontspec:

                self.fontspecs.append(fontspec)

            if fontspec.id:

                self.fontnames[fontspec.id] = fontspec

        dom_document.unlink()

        if not(self.default_fontspec):

            self.default_fontspec = DefaultFontSpec()

        self.build_tree()

    def build_tree(self):

        """

        Build the fontspec tree, the root node being the default font

        to apply. The fontspecs without a refmode (i.e. not being

        explicitely a subfont) are direct children of the default font.

        """

        to_ignore = []

        for fontspec in self.fontspecs:

            if fontspec.type == "ignore":

                to_ignore.append(fontspec)

                continue

            if not(fontspec.refmode):

                f = self.default_fontspec

            else:

                f = self.fontnames.get(fontspec.refmode, None)

            if (f):

                f.add_subfont(fontspec)

            else:

                raise ValueError("wrong fontspec tree")

        # Insert the characters to ignore in fontspecs

        for f in to_ignore:

            self.default_fontspec.add_ignored(f.get_uranges())

    def __str__(self):

        """Dump the instance's data attributes."""

        string = 'FontSpecConfig:'

        string += '\n  Fontspec list:'

        for fontspec in self.fontspecs:

            string += '\n' + _indent(str(fontspec), 4)

        return string