from collections import defaultdict, Counter

from progress_bar import progress
import sqlite3


class WordStats:
    def __init__(self, lemma_features):
        self.lemma_features = lemma_features

        self.all_words = 0
        self.memoized_msd_merges = {}

        with open("sqlite.db", 'w') as fp:
            fp.write("")

        self.db = sqlite3.connect('sqlite.db')
        self.db.execute("""CREATE TABLE UniqWords (
            uw_id INTEGER PRIMARY KEY, 
            lemma varchar(64), 
            msd varchar(16), 
            text varchar(64), 
            frequency int
            )""")
        self.db.execute("CREATE TABLE CommonMsd (lemma varchar(64), msd varchar(16))")
        self.db.execute("CREATE TABLE WordCount (lemma varchar(64), msd0 char, frequency int)")

        self.db.execute("CREATE INDEX lemma_msd_text_on_uw ON UniqWords (lemma, msd, text)")
        self.db.execute("CREATE INDEX lemma_on_uw ON UniqWords (lemma)")
        self.db.execute("CREATE INDEX lemma_on_cm ON CommonMsd (lemma)")
        self.db.execute("CREATE INDEX lemma_msd0_on_wc ON WordCount (lemma, msd0)")

    def add_words(self, words):
        for w in progress(words, "adding-words"):
            params = {'lemma': w.lemma, 'msd': w.msd, 'text': w.text}
            res = self.db.execute("""UPDATE UniqWords SET frequency=frequency + 1
                WHERE lemma=:lemma AND msd=:msd AND text=:text""", params)

            if res.rowcount == 0:
                self.db.execute("""INSERT INTO UniqWords (lemma, msd, text, frequency) 
                    VALUES (:lemma, :msd, :text, 1)""", params)

        self.db.commit()
        self.all_words += len(words)

    def num_all_words(self):
        return self.all_words

    def generate_renders(self):
        lemmas = [lemma for (lemma, ) in self.db.execute("SELECT DISTINCT lemma FROM UniqWords")]

        for lemma in progress(lemmas, 'common-msd'):
            common_msd = "*" * 10
            for msd in self.db.execute("SELECT DISTINCT msd FROM UniqWords WHERE lemma=?", (lemma,)):
                common_msd = self.merge_msd(common_msd, msd[0])
            common_msd = self.common_lemma_msd(lemma, common_msd)

            self.db.execute("INSERT INTO CommonMsd (lemma, msd) VALUES (?, ?)", (lemma, common_msd))
        self.db.commit()

        for lemma in progress(lemmas, 'word-count'):
            num_words = defaultdict(int)
            for (msd, freq) in self.db.execute("SELECT msd, frequency FROM UniqWords WHERE lemma=?", (lemma,)):
                num_words[msd[0]] += freq
                
            for msd0, freq in num_words.items():
                self.db.execute("INSERT INTO WordCount (lemma, msd0, frequency) VALUES (?,?,?)",
                    (lemma, msd0, freq))
        self.db.commit()

    def common_lemma_msd(self, lemma, msd):
        lf = self.lemma_features
        if msd[0] in lf:
            return "".join(
                l1 if l1 != "-" else l2 for l1, l2 in zip(lf[msd[0]], msd)
            )
        else:
            return msd

    def merge_msd(self, common_msd, new_msd):
        key = (common_msd, new_msd)
        if key in self.memoized_msd_merges:
            return self.memoized_msd_merges[key]

        def merge_letter(l1, l2):
            if l1 == "*":
                return l2
            elif l1 != l2:
                return "-"
            else:
                return l1

        value = "".join(merge_letter(l1, l2) for l1, l2 in zip(common_msd, new_msd))
        self.memoized_msd_merges[key] = value
        return value

    def render(self, lemma, msd):
        statement = """SELECT msd, frequency FROM UniqWords WHERE 
        lemma=:lemma AND msd=:msd ORDER BY frequency DESC"""

        cur = self.db.execute(statement, {"lemma": lemma, "msd": msd})
        if cur.rowcount > 0:
            return cur.fetchone()[0]

    def available_words(self, lemma, existing_texts):
        counted_texts = Counter(existing_texts)
        for (msd, text), _n in counted_texts.most_common():
            yield (msd, text)

        statement = """SELECT msd, text, frequency FROM UniqWords WHERE 
        lemma=:lemma ORDER BY frequency DESC"""
        for msd, text, _f in self.db.execute(statement, {'lemma': lemma}):
            yield (msd, text)
    
    def num_words(self, lemma, msd0):
        statement = "SELECT frequency FROM WordCount WHERE lemma=? AND msd0=? LIMIT 1"
        cur = self.db.execute(statement, (lemma, msd0))
        result = cur.fetchone()[0]
        return result


    def get_lemma_msd(self, lemma, word_msd):
        # should be here, since we collect every lemmas
        lemma_msd = self.db.execute("SELECT msd FROM CommonMsd WHERE lemma=?", (lemma,)).fetchone()[0]

        if lemma_msd[0] == '-':
            if word_msd[0] in self.lemma_features:
                return self.lemma_features[word_msd[0]]
            else:
                return '-'
        else:
            return lemma_msd