#!/usr/bin/env python
# -*- coding: utf-8 -*-
#
# This file is part of translate.
#
# translate 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.
#
# translate 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/>.

"""Create a terminology file by reading a set of .po or .pot files to produce a pootle-terminology.pot.

See: http://docs.translatehouse.org/projects/translate-toolkit/en/latest/commands/poterminology.html
for examples and usage instructions.
"""
import logging
import os
import re
import six
import sys
from operator import itemgetter

from translate.lang import factory as lang_factory
from translate.misc import file_discovery, optrecurse
from translate.storage import factory, po


logger = logging.getLogger(__name__)


def create_termunit(term, unit, targets, locations, sourcenotes, transnotes, filecounts):
    termunit = po.pounit(term)
    if unit is not None:
        termunit.merge(unit, overwrite=False, comments=False)
    if len(targets.keys()) > 1:
        txt = '; '.join(["%s {%s}" % (target, ', '.join(files))
                         for target, files in six.iteritems(targets)])
        if termunit.target.find('};') < 0:
            termunit.target = txt
            termunit.markfuzzy()
        else:
            # if annotated multiple terms already present, keep as-is
            termunit.addnote(txt, "translator")
    for location in locations:
        termunit.addlocation(location)
    for sourcenote in sourcenotes:
        termunit.addnote(sourcenote, "developer")
    for transnote in transnotes:
        termunit.addnote(transnote, "translator")
    for filename, count in six.iteritems(filecounts):
        termunit.addnote("(poterminology) %s (%d)\n" % (filename, count), 'translator')
    return termunit


class TerminologyExtractor(object):

    def __init__(self, foldtitle=True, ignorecase=False, accelchars="", termlength=3,
                 sourcelanguage="en", invert=False, stopfile=None):
        self.foldtitle = foldtitle
        self.ignorecase = ignorecase
        self.accelchars = accelchars
        self.termlength = termlength

        self.sourcelanguage = sourcelanguage
        self.invert = invert

        self.stopwords = {}
        self.stoprelist = []
        self.stopfoldtitle = True
        self.stopignorecase = False

        if stopfile is None:
            try:
                stopfile = file_discovery.get_abs_data_filename('stoplist-%s' % self.sourcelanguage)
            except Exception:
                pass
        self.stopfile = stopfile
        self.parse_stopword_file()

        # handles c-format and python-format
        self.formatpat = re.compile(r"%(?:\([^)]+\)|[0-9]+\$)?[-+#0]*[0-9.*]*(?:[hlLzjt][hl])?[EFGXc-ginoprsux]")
        # handles XML/HTML elements (<foo>text</foo> => text)
        self.xmlelpat = re.compile(r"<(?:![[-]|[/?]?[A-Za-z_:])[^>]*>")
        # handles XML/HTML entities (&#32; &#x20; &amp; &my_entity;)
        self.xmlentpat = re.compile(r"&(?:#(?:[0-9]+|x[0-9a-f]+)|[a-z_:][\w.-:]*);",
                                    flags=re.UNICODE | re.IGNORECASE)

        self.units = 0
        self.glossary = {}

    def parse_stopword_file(self):

        actions = {'+': frozenset(), ':': frozenset(['skip']),
                   '<': frozenset(['phrase']), '=': frozenset(['word']),
                   '>': frozenset(['word', 'skip']),
                   '@': frozenset(['word', 'phrase'])}

        with open(self.stopfile, "r") as stopfile:
            line = 0
            try:
                for stopline in stopfile:
                    line += 1
                    stoptype = stopline[0]
                    if stoptype == '#' or stoptype == "\n":
                        continue
                    elif stoptype == '!':
                        if stopline[1] == 'C':
                            self.stopfoldtitle = False
                            self.stopignorecase = False
                        elif stopline[1] == 'F':
                            self.stopfoldtitle = True
                            self.stopignorecase = False
                        elif stopline[1] == 'I':
                            self.stopignorecase = True
                        else:
                            logger.warning("%s:%d - bad case mapping directive",
                                           self.stopfile, line)
                    elif stoptype == '/':
                        self.stoprelist.append(re.compile(stopline[1:-1] + '$'))
                    else:
                        self.stopwords[stopline[1:-1]] = actions[stoptype]
            except KeyError as character:
                logger.warning("%s:%d - bad stopword entry starts with '%s'",
                               self.stopfile, line, str(character))
                logger.warning("%s:%d all lines after error ignored",
                               self.stopfile, line + 1)

    def clean(self, string):
        """returns the cleaned string that contains the text to be matched"""
        for accelerator in self.accelchars:
            string = string.replace(accelerator, "")
        string = self.formatpat.sub(" ", string)
        string = self.xmlelpat.sub(" ", string)
        string = self.xmlentpat.sub(" ", string)
        string = string.strip()
        return string

    def stopmap(self, word):
        """return case-mapped stopword for input word"""
        if self.stopignorecase or (self.stopfoldtitle and word.istitle()):
            word = word.lower()
        return word

    def stopword(self, word, defaultset=frozenset()):
        """return stoplist frozenset for input word"""
        return self.stopwords.get(self.stopmap(word), defaultset)

    def addphrases(self, words, skips, translation, partials=True):
        """adds (sub)phrases with non-skipwords and more than one word"""
        if (len(words) > skips + 1 and
            'skip' not in self.stopword(words[0]) and
            'skip' not in self.stopword(words[-1])):
            self.glossary.setdefault(' '.join(words), []).append(translation)
        if partials:
            part = list(words)
            while len(part) > 2:
                if 'skip' in self.stopword(part.pop()):
                    skips -= 1
                if (len(part) > skips + 1 and
                    'skip' not in self.stopword(part[0]) and
                    'skip' not in self.stopword(part[-1])):
                    self.glossary.setdefault(' '.join(part), []).append(translation)

    def processunits(self, units, fullinputpath):
        sourcelang = lang_factory.getlanguage(self.sourcelanguage)
        rematchignore = frozenset(('word', 'phrase'))
        defaultignore = frozenset()
        for unit in units:
            self.units += 1
            if unit.isheader():
                continue
            if not self.invert:
                source = self.clean(unit.source)
                target = self.clean(unit.target)
            else:
                target = self.clean(unit.source)
                source = self.clean(unit.target)
            if len(source) <= 1:
                continue
            for sentence in sourcelang.sentences(source):
                words = []
                skips = 0
                for word in sourcelang.words(sentence):
                    stword = self.stopmap(word)
                    if self.ignorecase or (self.foldtitle and word.istitle()):
                        word = word.lower()
                    ignore = defaultignore
                    if stword in self.stopwords:
                        ignore = self.stopwords[stword]
                    else:
                        for stopre in self.stoprelist:
                            if stopre.match(stword) is not None:
                                ignore = rematchignore
                                break
                    translation = (source, target, unit, fullinputpath)
                    if 'word' not in ignore:
                        # reduce plurals
                        root = word
                        if len(word) > 3 and word[-1] == 's' and word[0:-1] in self.glossary:
                            root = word[0:-1]
                        elif len(root) > 2 and root + 's' in self.glossary:
                            self.glossary[root] = self.glossary.pop(root + 's')
                        self.glossary.setdefault(root, []).append(translation)
                    if self.termlength > 1:
                        if 'phrase' in ignore:
                            # add trailing phrases in previous words
                            while len(words) > 2:
                                if 'skip' in self.stopword(words.pop(0)):
                                    skips -= 1
                                self.addphrases(words, skips, translation)
                            words = []
                            skips = 0
                        else:
                            words.append(word)
                            if 'skip' in ignore:
                                skips += 1
                            if len(words) > self.termlength + skips:
                                while len(words) > self.termlength + skips:
                                    if 'skip' in self.stopword(words.pop(0)):
                                        skips -= 1
                                self.addphrases(words, skips, translation)
                            else:
                                self.addphrases(words, skips, translation, partials=False)
                if self.termlength > 1:
                    # add trailing phrases in sentence after reaching end
                    while self.termlength > 1 and len(words) > 2:

                        if 'skip' in self.stopword(words.pop(0)):
                            skips -= 1
                        self.addphrases(words, skips, translation)

    def extract_terms(self, create_termunit=create_termunit, inputmin=1, fullmsgmin=1, substrmin=2, locmin=2):
        terms = {}
        locre = re.compile(r":[0-9]+$")
        logger.info("%d terms from %d units", len(self.glossary), self.units)
        for term, translations in six.iteritems(self.glossary):
            if len(translations) <= 1:
                continue
            filecounts = {}
            sources = set()
            locations = set()
            sourcenotes = set()
            transnotes = set()
            targets = {}
            fullmsg = False
            bestunit = None
            for source, target, unit, filename in translations:
                sources.add(source)
                filecounts[filename] = filecounts.setdefault(filename, 0) + 1
                # FIXME: why reclean source and target?!
                if term.lower() == self.clean(unit.source).lower():
                    fullmsg = True
                    target = self.clean(unit.target)
                    if self.ignorecase or (self.foldtitle and target.istitle()):
                        target = target.lower()
                    unit.target = target
                    if target != "":
                        targets.setdefault(target, []).append(filename)
                    if term.lower() == unit.source.strip().lower():
                        sourcenotes.add(unit.getnotes("source code"))
                        transnotes.add(unit.getnotes("translator"))
                    unit.source = term
                    bestunit = unit
                # FIXME: figure out why we did a merge to begin with
                # termunit.merge(unit, overwrite=False, comments=False)
                for loc in unit.getlocations():
                    locations.add(locre.sub("", loc))

            numsources = len(sources)
            numfiles = len(filecounts)
            numlocs = len(locations)
            if numfiles < inputmin or 0 < numlocs < locmin:
                continue
            if fullmsg:
                if numsources < fullmsgmin:
                    continue
            elif numsources < substrmin:
                continue

            locmax = 2 * locmin
            if numlocs > locmax:
                locations = list(locations)[0:locmax]
                locations.append("(poterminology) %d more locations" %
                                 (numlocs - locmax))

            termunit = create_termunit(term, bestunit, targets, locations, sourcenotes, transnotes, filecounts)
            terms[term] = ((10 * numfiles) + numsources, termunit)
        return terms

    sortorders_default = ["frequency", "dictionary", "length"]

    def filter_terms(self, terms, nonstopmin=1, sortorders=sortorders_default):
        """reduce subphrases from extracted terms"""
        # reduce subphrase
        termlist = sorted(terms.keys(), key=len)
        logger.info("%d terms after thresholding", len(termlist))
        for term in termlist:
            words = term.split()
            nonstop = [word for word in words if not self.stopword(word)]
            if len(nonstop) < nonstopmin and len(nonstop) != len(words):
                del terms[term]
                continue
            if len(words) <= 2:
                continue
            while len(words) > 2:
                words.pop()
                if terms[term][0] == terms.get(' '.join(words), [0])[0]:
                    del terms[' '.join(words)]
            words = term.split()
            while len(words) > 2:
                words.pop(0)
                if terms[term][0] == terms.get(' '.join(words), [0])[0]:
                    del terms[' '.join(words)]
        logger.info("%d terms after subphrase reduction", len(terms.keys()))
        termitems = list(terms.values())
        if sortorders is None:
            sortorders = self.sortorders_default
        while len(sortorders) > 0:
            order = sortorders.pop()
            if order == "frequency":
                termitems.sort(key=itemgetter(0), reverse=True)
            elif order == "dictionary":
                termitems.sort(key=lambda x: x[1].source.lower())
            elif order == "length":
                termitems.sort(key=lambda x: x[1].source)
            else:
                logger.warning("unknown sort order %s", order)
        return termitems


class TerminologyOptionParser(optrecurse.RecursiveOptionParser):
    """a specialized Option Parser for the terminology tool..."""

    def parse_args(self, args=None, values=None):
        """parses the command line options, handling implicit input/output args"""
        (options, args) = optrecurse.optparse.OptionParser.parse_args(self, args, values)
        # some intelligence as to what reasonable people might give on the command line
        if args and not options.input:
            if not options.output and not options.update and len(args) > 1:
                options.input = args[:-1]
                args = args[-1:]
            else:
                options.input = args
                args = []
        # don't overwrite last freestanding argument file, to avoid accidents
        # due to shell wildcard expansion
        if args and not options.output and not options.update:
            if os.path.lexists(args[-1]) and not os.path.isdir(args[-1]):
                self.error("To overwrite %s, specify it with -o/--output or -u/--update" % (args[-1]))
            options.output = args[-1]
            args = args[:-1]
        if options.output and options.update:
            self.error("You cannot use both -u/--update and -o/--output")
        if args:
            self.error("You have used an invalid combination of -i/--input, -o/--output, -u/--update and freestanding args")
        if not options.input:
            self.error("No input file or directory was specified")
        if isinstance(options.input, list) and len(options.input) == 1:
            options.input = options.input[0]
            if options.inputmin is None:
                options.inputmin = 1
        elif not isinstance(options.input, list) and not os.path.isdir(options.input):
            if options.inputmin is None:
                options.inputmin = 1
        elif options.inputmin is None:
            options.inputmin = 2
        if options.update:
            options.output = options.update
            if isinstance(options.input, list):
                options.input.append(options.update)
            elif options.input:
                options.input = [options.input, options.update]
            else:
                options.input = options.update
        if not options.output:
            options.output = "pootle-terminology.pot"
        return (options, args)

    def set_usage(self, usage=None):
        """sets the usage string - if usage not given, uses getusagestring for each option"""
        if usage is None:
            self.usage = "%prog " + " ".join([self.getusagestring(option) for option in self.option_list]) + \
                "\n  input directory is searched for PO files, terminology PO file is output file"
        else:
            super(TerminologyOptionParser, self).set_usage(usage)

    def run(self):
        """parses the arguments, and runs recursiveprocess with the resulting options"""
        self.files = 0
        (options, args) = self.parse_args()
        self.extractor = TerminologyExtractor(foldtitle=options.foldtitle, ignorecase=options.ignorecase,
                                              accelchars=options.accelchars, termlength=options.termlength,
                                              sourcelanguage=options.sourcelanguage,
                                              invert=options.invert, stopfile=options.stopfile)
        self.recursiveprocess(options)

    def recursiveprocess(self, options):
        """recurse through directories and process files"""
        if self.isrecursive(options.input, 'input') and getattr(options, "allowrecursiveinput", True):
            if isinstance(options.input, list):
                inputfiles = self.recurseinputfilelist(options)
            else:
                inputfiles = self.recurseinputfiles(options)
        else:
            if options.input:
                inputfiles = [os.path.basename(options.input)]
                options.input = os.path.dirname(options.input)
            else:
                inputfiles = [options.input]
        if os.path.isdir(options.output):
            options.output = os.path.join(options.output, "pootle-terminology.pot")

        progress_bar = optrecurse.ProgressBar(options.progress, inputfiles)
        for inputpath in inputfiles:
            self.files += 1
            fullinputpath = self.getfullinputpath(options, inputpath)
            success = True
            try:
                self.processfile(None, options, fullinputpath)
            except Exception:
                self.warning("Error processing: input %s" % (fullinputpath), options, sys.exc_info())
                success = False
            progress_bar.report_progress(inputpath, success)
        del progress_bar
        self.outputterminology(options)

    def processfile(self, fileprocessor, options, fullinputpath):
        """process an individual file"""
        inputfile = self.openinputfile(options, fullinputpath)
        inputfile = factory.getobject(inputfile)
        self.extractor.processunits(inputfile.units, fullinputpath)

    def outputterminology(self, options):
        """saves the generated terminology glossary"""
        termfile = po.pofile()
        logger.info("scanned %d files", self.files)
        terms = self.extractor.extract_terms(inputmin=options.inputmin,
                                             fullmsgmin=options.fullmsgmin,
                                             substrmin=options.substrmin,
                                             locmin=options.locmin)
        termitems = self.extractor.filter_terms(terms, nonstopmin=options.nonstopmin, sortorders=options.sortorders)
        for count, unit in termitems:
            termfile.units.append(unit)
        with open(options.output, "wb") as fh:
            termfile.serialize(fh)


def fold_case_option(option, opt_str, value, parser):
    parser.values.ignorecase = False
    parser.values.foldtitle = True


def preserve_case_option(option, opt_str, value, parser):
    parser.values.ignorecase = parser.values.foldtitle = False


def main():
    formats = {"po": ("po", None), "pot": ("pot", None), None: ("po", None)}
    parser = TerminologyOptionParser(formats)

    parser.add_option(
        "-u", "--update", type="string", dest="update",
        metavar="UPDATEFILE", help="update terminology in UPDATEFILE")

    parser.add_option("-S", "--stopword-list", type="string", metavar="STOPFILE", dest="stopfile",
                      help="read stopword (term exclusion) list from STOPFILE (default %s)" %
                      file_discovery.get_abs_data_filename('stoplist-en'))

    parser.set_defaults(foldtitle=True, ignorecase=False)
    parser.add_option(
        "-F", "--fold-titlecase", callback=fold_case_option,
        action="callback", help="fold \"Title Case\" to lowercase (default)")
    parser.add_option(
        "-C", "--preserve-case", callback=preserve_case_option,
        action="callback", help="preserve all uppercase/lowercase")
    parser.add_option(
        "-I", "--ignore-case", dest="ignorecase",
        action="store_true", help="make all terms lowercase")

    parser.add_option(
        "", "--accelerator", dest="accelchars", default="",
        metavar="ACCELERATORS", help="ignore the given accelerator characters when matching")

    parser.add_option(
        "-t", "--term-words", type="int", dest="termlength", default="3",
        help="generate terms of up to LENGTH words (default 3)", metavar="LENGTH")
    parser.add_option(
        "", "--nonstop-needed", type="int", dest="nonstopmin", default="1",
        help="omit terms with less than MIN nonstop words (default 1)", metavar="MIN")
    parser.add_option(
        "", "--inputs-needed", type="int", dest="inputmin",
        help="omit terms appearing in less than MIN input files (default 2, or 1 if only one input file)", metavar="MIN")
    parser.add_option(
        "", "--fullmsg-needed", type="int", dest="fullmsgmin", default="1",
        help="omit full message terms appearing in less than MIN different messages (default 1)", metavar="MIN")
    parser.add_option(
        "", "--substr-needed", type="int", dest="substrmin", default="2",
        help="omit substring-only terms appearing in less than MIN different messages (default 2)", metavar="MIN")
    parser.add_option(
        "", "--locs-needed", type="int", dest="locmin", default="2",
        help="omit terms appearing in less than MIN different original source files (default 2)", metavar="MIN")

    parser.add_option(
        "", "--sort", dest="sortorders", action="append",
        type="choice", choices=TerminologyExtractor.sortorders_default, metavar="ORDER",
        help="output sort order(s): %s (may repeat option, default is all in above order)" % ', '.join(TerminologyExtractor.sortorders_default))

    parser.add_option(
        "", "--source-language", dest="sourcelanguage", default="en",
        help="the source language code (default 'en')", metavar="LANG")
    parser.add_option(
        "-v", "--invert", dest="invert",
        action="store_true", default=False, help="invert the source and target languages for terminology")
    parser.set_usage()
    parser.description = __doc__
    parser.run()


if __name__ == '__main__':
    main()
