shared_lig.py

from fontTools import ttLib
import xml.etree.ElementTree as ET
from shared import genders

name_map = {
    'u0023': 'numbersign',
    'u002A': 'asterisk',
    'u0030': 'zero',
    'u0031': 'one',
    'u0032': 'two',
    'u0033': 'three',
    'u0034': 'four',
    'u0035': 'five',
    'u0036': 'six',
    'u0037': 'seven',
    'u0038': 'eight',
    'u0039': 'nine',
}

class Lig:
    def __init__(self, f: ttLib.TTFont, bttf: str, bgsubttx: str):
        b = ttLib.TTFont(bttf)
        self.bgsub = ET.parse(bgsubttx).getroot()
        self.blig = {}
        self.icmap = f.get('cmap').buildReversed()
        self.cmap = f.get('cmap').tables[0].cmap
        self.bicmap = b.get('cmap').buildReversed()
        self.bcmap = b.get('cmap').tables[1].cmap

    def get_apple_code(self, code: str):
        code = next(iter(self.bicmap[code]))
        if code == 0x200D:
            return 'u200D'
        if code in self.cmap:
            code = self.cmap[code]
        code = str(code)
        code = code.replace('.0', '')
        return code

    def norm_name(self, name: str):
        name = name.upper()
        tokens = name.split('_')
        s = []
        for t in tokens:
            t = f'uni{t}' if t in genders else f'u{t}'
            s.append(t)
        if s[0] in name_map:
            s[0] = name_map[s[0]]
        return '_'.join(s)

    def build(self):
        print('Building ligatures...')
        self.bicmap_apple = {}
        for key in self.bicmap:
            self.bicmap_apple[self.get_apple_code(key)] = self.bicmap[key]

        for lookup in self.bgsub.iter('Lookup'):
            lookup_type = lookup.find('LookupType').get('value')
            if lookup_type != '4':
                continue
            for ligset in lookup.iter('LigatureSet'):
                glyph = self.get_apple_code(ligset.get('glyph'))
                for lig in ligset.iter('Ligature'):
                    components = str(lig.get('components'))
                    tokens = components.split(',')
                    s = []
                    for t in tokens:
                        s.append(self.get_apple_code(t))
                    remaining = '_'.join(s)
                    name = f'{glyph}_{remaining}'
                    real_glyph = lig.get('glyph')
                    self.blig[name] = real_glyph

    def get_glyph_name(self, name: str):
        if name in self.icmap:
            code = next(iter(self.icmap[name]))
            return self.bcmap[code]
        if name in self.bicmap_apple:
            code = next(iter(self.bicmap_apple[name]))
            return self.bcmap[code]
        if name in self.blig:
            return self.blig[name]
        return name