# Natural Language Toolkit: NKJP Corpus Reader
#
# Copyright (C) 2001-2021 NLTK Project
# Author: Gabriela Kaczka
# URL: <http://nltk.org/>
# For license information, see LICENSE.TXT

import functools
import os
import re
import tempfile

from nltk.corpus.reader.util import concat
from nltk.corpus.reader.xmldocs import XMLCorpusReader, XMLCorpusView


def _parse_args(fun):
    """
    Wraps function arguments:
    if fileids not specified then function set NKJPCorpusReader paths.
    """

    @functools.wraps(fun)
    def decorator(self, fileids=None, **kwargs):
        if not fileids:
            fileids = self._paths
        return fun(self, fileids, **kwargs)

    return decorator


class NKJPCorpusReader(XMLCorpusReader):
    WORDS_MODE = 0
    SENTS_MODE = 1
    HEADER_MODE = 2
    RAW_MODE = 3

    def __init__(self, root, fileids=".*"):
        """
        Corpus reader designed to work with National Corpus of Polish.
        See http://nkjp.pl/ for more details about NKJP.
        use example:
        import nltk
        import nkjp
        from nkjp import NKJPCorpusReader
        x = NKJPCorpusReader(root='/home/USER/nltk_data/corpora/nkjp/', fileids='') # obtain the whole corpus
        x.header()
        x.raw()
        x.words()
        x.tagged_words(tags=['subst', 'comp'])  #Link to find more tags: nkjp.pl/poliqarp/help/ense2.html
        x.sents()
        x = NKJPCorpusReader(root='/home/USER/nltk_data/corpora/nkjp/', fileids='Wilk*') # obtain particular file(s)
        x.header(fileids=['WilkDom', '/home/USER/nltk_data/corpora/nkjp/WilkWilczy'])
        x.tagged_words(fileids=['WilkDom', '/home/USER/nltk_data/corpora/nkjp/WilkWilczy'], tags=['subst', 'comp'])
        """
        if isinstance(fileids, str):
            XMLCorpusReader.__init__(self, root, fileids + ".*/header.xml")
        else:
            XMLCorpusReader.__init__(
                self, root, [fileid + "/header.xml" for fileid in fileids]
            )
        self._paths = self.get_paths()

    def get_paths(self):
        return [
            os.path.join(str(self._root), f.split("header.xml")[0])
            for f in self._fileids
        ]

    def fileids(self):
        """
        Returns a list of file identifiers for the fileids that make up
        this corpus.
        """
        return [f.split("header.xml")[0] for f in self._fileids]

    def _view(self, filename, tags=None, **kwargs):
        """
        Returns a view specialised for use with particular corpus file.
        """
        mode = kwargs.pop("mode", NKJPCorpusReader.WORDS_MODE)
        if mode is NKJPCorpusReader.WORDS_MODE:
            return NKJPCorpus_Morph_View(filename, tags=tags)
        elif mode is NKJPCorpusReader.SENTS_MODE:
            return NKJPCorpus_Segmentation_View(filename, tags=tags)
        elif mode is NKJPCorpusReader.HEADER_MODE:
            return NKJPCorpus_Header_View(filename, tags=tags)
        elif mode is NKJPCorpusReader.RAW_MODE:
            return NKJPCorpus_Text_View(
                filename, tags=tags, mode=NKJPCorpus_Text_View.RAW_MODE
            )

        else:
            raise NameError("No such mode!")

    def add_root(self, fileid):
        """
        Add root if necessary to specified fileid.
        """
        if self.root in fileid:
            return fileid
        return self.root + fileid

    @_parse_args
    def header(self, fileids=None, **kwargs):
        """
        Returns header(s) of specified fileids.
        """
        return concat(
            [
                self._view(
                    self.add_root(fileid), mode=NKJPCorpusReader.HEADER_MODE, **kwargs
                ).handle_query()
                for fileid in fileids
            ]
        )

    @_parse_args
    def sents(self, fileids=None, **kwargs):
        """
        Returns sentences in specified fileids.
        """
        return concat(
            [
                self._view(
                    self.add_root(fileid), mode=NKJPCorpusReader.SENTS_MODE, **kwargs
                ).handle_query()
                for fileid in fileids
            ]
        )

    @_parse_args
    def words(self, fileids=None, **kwargs):
        """
        Returns words in specified fileids.
        """

        return concat(
            [
                self._view(
                    self.add_root(fileid), mode=NKJPCorpusReader.WORDS_MODE, **kwargs
                ).handle_query()
                for fileid in fileids
            ]
        )

    @_parse_args
    def tagged_words(self, fileids=None, **kwargs):
        """
        Call with specified tags as a list, e.g. tags=['subst', 'comp'].
        Returns tagged words in specified fileids.
        """
        tags = kwargs.pop("tags", [])
        return concat(
            [
                self._view(
                    self.add_root(fileid),
                    mode=NKJPCorpusReader.WORDS_MODE,
                    tags=tags,
                    **kwargs
                ).handle_query()
                for fileid in fileids
            ]
        )

    @_parse_args
    def raw(self, fileids=None, **kwargs):
        """
        Returns words in specified fileids.
        """
        return concat(
            [
                self._view(
                    self.add_root(fileid), mode=NKJPCorpusReader.RAW_MODE, **kwargs
                ).handle_query()
                for fileid in fileids
            ]
        )


class NKJPCorpus_Header_View(XMLCorpusView):
    def __init__(self, filename, **kwargs):
        """
        HEADER_MODE
        A stream backed corpus view specialized for use with
        header.xml files in NKJP corpus.
        """
        self.tagspec = ".*/sourceDesc$"
        XMLCorpusView.__init__(self, filename + "header.xml", self.tagspec)

    def handle_query(self):
        self._open()
        header = []
        while True:
            segm = XMLCorpusView.read_block(self, self._stream)
            if len(segm) == 0:
                break
            header.extend(segm)
        self.close()
        return header

    def handle_elt(self, elt, context):
        titles = elt.findall("bibl/title")
        title = []
        if titles:
            title = "\n".join(title.text.strip() for title in titles)

        authors = elt.findall("bibl/author")
        author = []
        if authors:
            author = "\n".join(author.text.strip() for author in authors)

        dates = elt.findall("bibl/date")
        date = []
        if dates:
            date = "\n".join(date.text.strip() for date in dates)

        publishers = elt.findall("bibl/publisher")
        publisher = []
        if publishers:
            publisher = "\n".join(publisher.text.strip() for publisher in publishers)

        idnos = elt.findall("bibl/idno")
        idno = []
        if idnos:
            idno = "\n".join(idno.text.strip() for idno in idnos)

        notes = elt.findall("bibl/note")
        note = []
        if notes:
            note = "\n".join(note.text.strip() for note in notes)

        return {
            "title": title,
            "author": author,
            "date": date,
            "publisher": publisher,
            "idno": idno,
            "note": note,
        }


class XML_Tool:
    """
    Helper class creating xml file to one without references to nkjp: namespace.
    That's needed because the XMLCorpusView assumes that one can find short substrings
    of XML that are valid XML, which is not true if a namespace is declared at top level
    """

    def __init__(self, root, filename):
        self.read_file = os.path.join(root, filename)
        self.write_file = tempfile.NamedTemporaryFile(delete=False)

    def build_preprocessed_file(self):
        try:
            fr = open(self.read_file, "r")
            fw = self.write_file
            line = " "
            while len(line):
                line = fr.readline()
                x = re.split(r"nkjp:[^ ]* ", line)  # in all files
                ret = " ".join(x)
                x = re.split("<nkjp:paren>", ret)  # in ann_segmentation.xml
                ret = " ".join(x)
                x = re.split("</nkjp:paren>", ret)  # in ann_segmentation.xml
                ret = " ".join(x)
                x = re.split("<choice>", ret)  # in ann_segmentation.xml
                ret = " ".join(x)
                x = re.split("</choice>", ret)  # in ann_segmentation.xml
                ret = " ".join(x)
                fw.write(ret)
            fr.close()
            fw.close()
            return self.write_file.name
        except Exception as e:
            self.remove_preprocessed_file()
            raise Exception from e

    def remove_preprocessed_file(self):
        os.remove(self.write_file.name)


class NKJPCorpus_Segmentation_View(XMLCorpusView):
    """
    A stream backed corpus view specialized for use with
    ann_segmentation.xml files in NKJP corpus.
    """

    def __init__(self, filename, **kwargs):
        self.tagspec = ".*p/.*s"
        # intersperse NKJPCorpus_Text_View
        self.text_view = NKJPCorpus_Text_View(
            filename, mode=NKJPCorpus_Text_View.SENTS_MODE
        )
        self.text_view.handle_query()
        # xml preprocessing
        self.xml_tool = XML_Tool(filename, "ann_segmentation.xml")
        # base class init
        XMLCorpusView.__init__(
            self, self.xml_tool.build_preprocessed_file(), self.tagspec
        )

    def get_segm_id(self, example_word):
        return example_word.split("(")[1].split(",")[0]

    def get_sent_beg(self, beg_word):
        # returns index of beginning letter in sentence
        return int(beg_word.split(",")[1])

    def get_sent_end(self, end_word):
        # returns index of end letter in sentence
        splitted = end_word.split(")")[0].split(",")
        return int(splitted[1]) + int(splitted[2])

    def get_sentences(self, sent_segm):
        # returns one sentence
        id = self.get_segm_id(sent_segm[0])
        segm = self.text_view.segm_dict[id]  # text segment
        beg = self.get_sent_beg(sent_segm[0])
        end = self.get_sent_end(sent_segm[len(sent_segm) - 1])
        return segm[beg:end]

    def remove_choice(self, segm):
        ret = []
        prev_txt_end = -1
        prev_txt_nr = -1
        for word in segm:
            txt_nr = self.get_segm_id(word)
            # get increasing sequence of ids: in case of choice get first possibility
            if self.get_sent_beg(word) > prev_txt_end - 1 or prev_txt_nr != txt_nr:
                ret.append(word)
                prev_txt_end = self.get_sent_end(word)
            prev_txt_nr = txt_nr

        return ret

    def handle_query(self):
        try:
            self._open()
            sentences = []
            while True:
                sent_segm = XMLCorpusView.read_block(self, self._stream)
                if len(sent_segm) == 0:
                    break
                for segm in sent_segm:
                    segm = self.remove_choice(segm)
                    sentences.append(self.get_sentences(segm))
            self.close()
            self.xml_tool.remove_preprocessed_file()
            return sentences
        except Exception as e:
            self.xml_tool.remove_preprocessed_file()
            raise Exception from e

    def handle_elt(self, elt, context):
        ret = []
        for seg in elt:
            ret.append(seg.get("corresp"))
        return ret


class NKJPCorpus_Text_View(XMLCorpusView):
    """
    A stream backed corpus view specialized for use with
    text.xml files in NKJP corpus.
    """

    SENTS_MODE = 0
    RAW_MODE = 1

    def __init__(self, filename, **kwargs):
        self.mode = kwargs.pop("mode", 0)
        self.tagspec = ".*/div/ab"
        self.segm_dict = dict()
        # xml preprocessing
        self.xml_tool = XML_Tool(filename, "text.xml")
        # base class init
        XMLCorpusView.__init__(
            self, self.xml_tool.build_preprocessed_file(), self.tagspec
        )

    def handle_query(self):
        try:
            self._open()
            x = self.read_block(self._stream)
            self.close()
            self.xml_tool.remove_preprocessed_file()
            return x
        except Exception as e:
            self.xml_tool.remove_preprocessed_file()
            raise Exception from e

    def read_block(self, stream, tagspec=None, elt_handler=None):
        """
        Returns text as a list of sentences.
        """
        txt = []
        while True:
            segm = XMLCorpusView.read_block(self, stream)
            if len(segm) == 0:
                break
            for part in segm:
                txt.append(part)

        return [" ".join([segm for segm in txt])]

    def get_segm_id(self, elt):
        for attr in elt.attrib:
            if attr.endswith("id"):
                return elt.get(attr)

    def handle_elt(self, elt, context):
        # fill dictionary to use later in sents mode
        if self.mode is NKJPCorpus_Text_View.SENTS_MODE:
            self.segm_dict[self.get_segm_id(elt)] = elt.text
        return elt.text


class NKJPCorpus_Morph_View(XMLCorpusView):
    """
    A stream backed corpus view specialized for use with
    ann_morphosyntax.xml files in NKJP corpus.
    """

    def __init__(self, filename, **kwargs):
        self.tags = kwargs.pop("tags", None)
        self.tagspec = ".*/seg/fs"
        self.xml_tool = XML_Tool(filename, "ann_morphosyntax.xml")
        XMLCorpusView.__init__(
            self, self.xml_tool.build_preprocessed_file(), self.tagspec
        )

    def handle_query(self):
        try:
            self._open()
            words = []
            while True:
                segm = XMLCorpusView.read_block(self, self._stream)
                if len(segm) == 0:
                    break
                for part in segm:
                    if part is not None:
                        words.append(part)
            self.close()
            self.xml_tool.remove_preprocessed_file()
            return words
        except Exception as e:
            self.xml_tool.remove_preprocessed_file()
            raise Exception from e

    def handle_elt(self, elt, context):
        word = ""
        flag = False
        is_not_interp = True
        # if tags not specified, then always return word
        if self.tags is None:
            flag = True

        for child in elt:

            # get word
            if "name" in child.keys() and child.attrib["name"] == "orth":
                for symbol in child:
                    if symbol.tag == "string":
                        word = symbol.text
            elif "name" in child.keys() and child.attrib["name"] == "interps":
                for symbol in child:
                    if "type" in symbol.keys() and symbol.attrib["type"] == "lex":
                        for symbol2 in symbol:
                            if (
                                "name" in symbol2.keys()
                                and symbol2.attrib["name"] == "ctag"
                            ):
                                for symbol3 in symbol2:
                                    if (
                                        "value" in symbol3.keys()
                                        and self.tags is not None
                                        and symbol3.attrib["value"] in self.tags
                                    ):
                                        flag = True
                                    elif (
                                        "value" in symbol3.keys()
                                        and symbol3.attrib["value"] == "interp"
                                    ):
                                        is_not_interp = False
        if flag and is_not_interp:
            return word
