#
# Copyright 2008-2009 Zuza Software Foundation
#
# This file is part of the Translate Toolkit.
#
# This program 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.
#
# This program 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 this program; if not, see <http://www.gnu.org/licenses/>.

"""
Segment Gettext PO, XLIFF and TMX localization files at the sentence level.

See: http://docs.translatehouse.org/projects/translate-toolkit/en/latest/commands/posegment.html
for examples and usage instructions.
"""

from translate.convert import convert
from translate.lang import factory as lang_factory
from translate.storage import factory, poheader


class segment:
    def __init__(
        self, sourcelang, targetlang, stripspaces=True, onlyaligned=False
    ) -> None:
        self.sourcelang = sourcelang
        self.targetlang = targetlang
        self.stripspaces = stripspaces
        self.onlyaligned = onlyaligned

    def segmentunit(self, unit):
        if unit.isheader() or unit.hasplural():
            return [unit]
        sourcesegments = self.sourcelang.sentences(unit.source, strip=self.stripspaces)
        targetsegments = self.targetlang.sentences(unit.target, strip=self.stripspaces)
        if unit.istranslated() and (len(sourcesegments) != len(targetsegments)):
            if not self.onlyaligned:
                return [unit]
            return None
        # We could do more here to check if the lengths correspond more or less,
        # certain quality checks are passed, etc.  But for now this is a good
        # start.
        units = []
        for i, source in enumerate(sourcesegments):
            newunit = unit.copy()
            newunit.source = source
            if not unit.istranslated():
                newunit.target = ""
            else:
                newunit.target = targetsegments[i]
            units.append(newunit)
        return units

    def convertstore(self, fromstore):
        tostore = type(fromstore)()
        # We don't want the default header in the case of PO, but rather the
        # one from `fromstore`.
        if isinstance(fromstore, poheader.poheader) and fromstore.header() is not None:
            tostore.units = []
        for unit in fromstore.units:
            newunits = self.segmentunit(unit)
            if newunits:
                for newunit in newunits:
                    tostore.addunit(newunit)
        return tostore


def segmentfile(
    inputfile,
    outputfile,
    templatefile,
    sourcelanguage="en",
    targetlanguage=None,
    stripspaces=True,
    onlyaligned=False,
) -> int:
    """Reads in inputfile, segments it then, writes to outputfile."""
    # note that templatefile is not used, but it is required by the converter...
    inputstore = factory.getobject(inputfile)
    if inputstore.isempty():
        return 0
    sourcelang = lang_factory.getlanguage(sourcelanguage)
    targetlang = lang_factory.getlanguage(targetlanguage)
    convertor = segment(
        sourcelang, targetlang, stripspaces=stripspaces, onlyaligned=onlyaligned
    )
    outputstore = convertor.convertstore(inputstore)
    outputstore.serialize(outputfile)
    return 1


def main() -> None:
    formats = {
        "po": ("po", segmentfile),
        "xlf": ("xlf", segmentfile),
        "xliff": ("xliff", segmentfile),
        "tmx": ("tmx", segmentfile),
    }
    parser = convert.ConvertOptionParser(formats, usepots=True, description=__doc__)
    parser.add_option(
        "-l",
        "--language",
        dest="targetlanguage",
        default=None,
        help="the target language code",
        metavar="LANG",
    )
    parser.add_option(
        "",
        "--source-language",
        dest="sourcelanguage",
        default=None,
        help="the source language code (default 'en')",
        metavar="LANG",
    )
    parser.passthrough.append("sourcelanguage")
    parser.passthrough.append("targetlanguage")
    parser.add_option(
        "",
        "--keepspaces",
        dest="stripspaces",
        action="store_false",
        default=True,
        help="Disable automatic stripping of whitespace",
    )
    parser.passthrough.append("stripspaces")
    parser.add_option(
        "",
        "--only-aligned",
        dest="onlyaligned",
        action="store_true",
        default=False,
        help="Removes units where sentence number does not correspond",
    )
    parser.passthrough.append("onlyaligned")
    parser.run()


if __name__ == "__main__":
    main()
