A script to run on UFO files from a command line. Goes through a pair list and copy kerns from one UFO to others, if those kern pairs are in the pair list.

copy-kerning-in-pair_list-from-ufo-to-ufos.py

"""
    A script to run on UFO files from a command line. Goes through a pair list and 
    copy kerns from one UFO to others, if those kern pairs are in the pair list.

    What happens:
    - copy groups from ufoToCopyFrom to each other UFOs
    - for each pair in the pair list, copy kern from ufoToCopyFrom to each other UFOs
    
    ---

    USAGE:

    python "DIR/PATH/copy-kerning-in-pair_list-without-metrics_machine.py" "DIR/PATH/pair_list.txt" "ufo/to/copy/from" "dir/to/copy/to"

    Required argument: Pair list, as exported from Metrics Machine, e.g.

        #KPL:P: UC and Punc
        H hyphen
        hyphen H
        H parenleft
        # etc

    Required argument: File path of UFO to copy groups from

    Optional argument: Dir path of UFOs to copy to (if not set, this assumes 
    you wish to copy to all UFOs in the same dir as the first one given)
    
    ---

    ASSUMPTIONS:

        - Your kerning groups include exact glyph names from your font, 
          e.g. "public.kern1.quotesingle", NOT "public.kern1.quotes_basic".

        - You wish to exactly copy groups.plist from the UFO path to all 
          other UFOs in the same directory (to ensure similar groups).

        - You wish to exactly copy kerning data from the pair list from 
          the UFO path to all UFOs in a specified directory.

        - You are working with Git, so you can spot-check changes before 
          truly saving them.

    ------------------------------------------------------------------------

    MIT License.

    Copyright 2020 Arrow Type LLC / Stephen Nixon

    Permission is hereby granted, free of charge, to any person obtaining a 
    copy of this software and associated documentation files (the "Software"), 
    to deal in the Software without restriction, including without limitation 
    the rights to use, copy, modify, merge, publish, distribute, sublicense, 
    and/or sell copies of the Software, and to permit persons to whom the 
    Software is furnished to do so, subject to the following conditions:

    The above copyright notice and this permission notice shall be included 
    in all copies or substantial portions of the Software.

    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS 
    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 
    AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 
    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 
    FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 
    DEALINGS IN THE SOFTWARE.
"""

import sys
import os
import shutil
from fontParts.world import OpenFont, RFont
from ufonormalizer import normalizeUFO

# Deal with arguments

try:
    if sys.argv[1].endswith(".txt"):
        kerningPairFile = sys.argv[1]
    else:
        print("You must include a kerning pair .txt file")
except IndexError:
    print("You must include a kerning pair .txt file")

try:
    if sys.argv[2].endswith(".ufo"):
        ufoToCopyFrom = sys.argv[2]
    else:
        print("The second arg must be the path of UFO to copy groups & kerning from")
except IndexError:
    print("The second arg must be the path of UFO to copy groups & kerning from")

try:
    if sys.argv[3]:
        print("Copying from UFO to UFOs in another Directory")
        dirToCopyTo = sys.argv[3]
        ufosToCopyTo = next(os.walk(dirToCopyTo))[1]

        head, tail = dirToCopyTo, os.path.split(ufoToCopyFrom)[1]
except IndexError:
    print("Copying from UFO to UFOs in the same Directory")
    head, tail = os.path.split(ufoToCopyFrom)
    ufosToCopyTo = next(os.walk(head))[1]


# ----------------------------------------------------------------
# COPY GROUPS

groupsPath = f"{ufoToCopyFrom}/groups.plist"

for ufo in sorted(ufosToCopyTo):
    ufoPath = f"{head}/{ufo}"

    if ufoPath != ufoToCopyFrom and ".ufo" in ufoPath and "sparse" not in ufoPath:
        print(ufoPath)
        groupsDest = f"{ufoPath}/groups.plist"
        shutil.copyfile(groupsPath, groupsDest)


# ----------------------------------------------------------------
# COPY KERNS

# READ PAIR LIST

pairList = []

pairsGrouped = {}

with open(kerningPairFile) as f:
    data = f.read()

    for line in data.split("\n"):
        if line[0] != "#":
            # maybe make line into tuple?
            pairList.append(line.split(" "))

# HELPERS


def getKernValue(font, pair):
    "Try possible combinations to find the value of a given kerning pair, if it exists"

    try:
        return font.kerning[(pair[0], pair[1])]
    except KeyError:
        pass
    try:
        return font.kerning[(f"public.kern1.{pair[0]}", pair[1])]
    except KeyError:
        pass
    try:
        return font.kerning[(pair[0], f"public.kern2.{pair[1]}")]
    except KeyError:
        pass
    try:
        return font.kerning[(f"public.kern1.{pair[0]}", f"public.kern2.{pair[1]}")]
    except:
        pass

    return None


def setKernValue(font, pair, value):

    # find if left/right of pair in groups
    leftGroup = ""
    rightGroup = ""

    for group in font.groups.keys():
        if "kern1" in group and pair[0] in font.groups[group]:
            leftGroup = group

        if "kern2" in group and pair[1] in font.groups[group]:
            rightGroup = group

    # set kerning by group if you should
    if leftGroup and rightGroup:
        font.kerning[(leftGroup, rightGroup)] = value

    elif leftGroup:
        font.kerning[(leftGroup, pair[1])] = value

    elif rightGroup:
        font.kerning[(pair[0], rightGroup)] = value

    # otherwise, just set lone pair
    else:
        font.kerning[(pair[0], pair[1])] = value


fontToCopyFrom = OpenFont(ufoToCopyFrom, showInterface=False)

for ufo in sorted(ufosToCopyTo):
    ufoPath = f"{head}/{ufo}"

    if ufoPath != ufoToCopyFrom and ".ufo" in ufoPath and "sparse" not in ufoPath:
        print("copying kerning pairs to ", ufoPath)

        fontToCopyTo = OpenFont(ufoPath, showInterface=False)

        for pair in pairList:
            valueToCopy = getKernValue(fontToCopyFrom, pair)
            if valueToCopy:
                setKernValue(fontToCopyTo, pair, valueToCopy)

        fontToCopyTo.save()

        # makes saved UFO not have changes outside of kern updates
        normalizeUFO(ufoPath, writeModTimes=False)

        fontToCopyTo.close()

print("All Done!")