from xml.etree import ElementTree
import logging
import re
import sys
import gzip
import pathlib

from progress_bar import progress
from word import Word


def is_root_id(id_):
    return len(id_.split('.')) == 3


def load_files(args, database):
    filenames = args.input
    skip_id_check = args.skip_id_check
    do_msd_translate = not args.no_msd_translate

    database.init("CREATE TABLE Files ( filename varchar(2048) )")

    for idx, fname in enumerate(filenames):
        print("FILE ", fname, "{}/{}".format(idx, len(filenames)))
        extension = pathlib.Path(fname).suffix

        # check if file with the same name already loaded...
        loaded = database.execute("SELECT * FROM Files WHERE filename=?", (fname, )).fetchone()
        if loaded is not None:
            print("ALREADY LOADED")
            continue

        if extension == ".xml":
            et = load_xml(fname)
            yield file_sentence_generator(et, skip_id_check, do_msd_translate, args.pc_tag)
        elif extension == ".gz":
            yield load_csv(fname, True)
        else:
            yield load_csv(fname, False)
        # else:
        #     raise NotImplementedError("Unknown file extension: {}".format(extension))

        database.execute("INSERT INTO Files (filename) VALUES (?)", (fname, ))
        database.commit()


def lines_gz(filename):
    with gzip.open(filename, 'r') as fp:
        for line in progress(fp, 'load-gz'):
            yield line.decode('utf8')


def lines_csv(filename):
    with open(filename, 'r') as fp:
        for line in progress(fp, 'load-csv'):
            yield line


def load_csv(filename, compressed):
    result = []
    bad_sentence = False

    words = {}
    links = []

    def sentence_end(bad_sentence):
        if bad_sentence:
            return

        for lfrom, ldest, ana in links:
            if lfrom not in words or ldest not in words:
                logging.warning("Bad link in sentence: " + line_split[0])
                continue
            words[lfrom].add_link(ana, words[ldest])
        result.extend(words.values())

    line_gen = lines_gz if compressed else lines_csv
    for line in line_gen(filename):
        line_str = line.strip()
        line_fixed = line_str.replace(',', '\t').replace('\t\t\t', '\t,\t')
        line_split = line_fixed.split("\t")

        if line_split[1] == "1" and len(words) > 0:
            sentence_end(bad_sentence)
            bad_sentence = False
            links = []
            words = {}

        try:
            sid, wid, text, msd, lemma, link_src, link_type = line_split
        except ValueError:
            bad_sentence = True
        full_id = "{}.{}".format(sid, wid)
        
        words[wid] = Word(lemma, msd, full_id, text, True)
        if link_src != '0':
            links.append((link_src, wid, link_type))
    
    sentence_end(bad_sentence)
    return result

def load_xml(filename):
    with open(filename, 'r') as fp:
        content = fp.read()

    xmlstring = re.sub(' xmlns="[^"]+"', '', content, count=1)
    xmlstring = xmlstring.replace(' xml:', ' ')
    return ElementTree.XML(xmlstring)


def file_sentence_generator(et, skip_id_check, do_msd_translate, pc_tag):
    words = {}
    sentences = list(et.iter('s'))
    for sentence in progress(sentences, "load-text"):
        for w in sentence.iter("w"):
            words[w.get('id')] = Word.from_xml(w, do_msd_translate)
        for pc in sentence.iter(pc_tag):
            words[pc.get('id')] = Word.pc_word(pc, do_msd_translate)

        for l in sentence.iter("link"):
            if 'dep' in l.keys():
                ana = l.get('afun')
                lfrom = l.get('from')
                dest = l.get('dep')
            else:
                ana = l.get('ana')
                if ana[:4] != 'syn:': # dont bother...
                    continue
                ana = ana[4:]
                lfrom, dest = l.get('target').replace('#', '').split()

            if lfrom in words:
                if not skip_id_check and is_root_id(lfrom):
                    logging.error("NOO: {}".format(lfrom))
                    sys.exit(1)

                if dest in words:
                    next_word = words[dest]
                    words[lfrom].add_link(ana, next_word)
                else:
                    logging.error("Unknown id: {}".format(dest))
                    sys.exit(1)

            else:
                # strange errors, just skip...
                pass

    return list(words.values())