#!/usr/bin/python3
# -*- coding: utf-8 -*-


from config import max_age
import hashlib
import sqlite3
import time
import tweepy


class LikeMemory():
    """Track all liked Tweets."""

    def __init__(self, api):
        """Build the Python object."""

        self._api = api

        self._db = sqlite3.connect('HTT.db', detect_types=sqlite3.PARSE_DECLTYPES)

        sqlite3.register_adapter(bool, int)
        sqlite3.register_converter("BOOLEAN", lambda v: bool(int(v)))

        sql = '''
            CREATE TABLE IF NOT EXISTS LikedTweets(
                sid INTEGER PRIMARY KEY,
                username TEXT,
                fingerprint TEXT,
                timestamp INTEGER,
                purged BOOLEAN
            )
        '''

        cursor = self._db.cursor()
        cursor.execute(sql)
        self._db.commit()


    def _compute_content_fingerprint(self, content):
        """Compute the fingerprint of a given status content."""

        # Step 1: filter all hashtags

        cut = content.split(' ')

        content = ' '.join([ c for c in cut if not c.startswith('#') ])

        # Step 2: stop at the first link

        cut = content.split(' ')

        keep = []

        for c in cut:

            if c.startswith('http://') or c.startswith('https://'):
                break

            keep.append(c)

        content = ' '.join(keep)

        # Step 3: get a fresh start

        separators = ':-!?.'

        content = content.lstrip(' ' + separators)

        # Step 4: Extract a common shared base

        base = content

        for sep in separators:

            pos = base.find(sep)

            if pos != -1:
                base = base[:pos]

        return hashlib.md5(base.rstrip(' ').encode('utf-8')).hexdigest()


    def is_original_content(self, content):
        """Ensure that a given content has never been seen."""

        fingerprint = self._compute_content_fingerprint(content)

        values = (fingerprint, )

        cursor = self._db.cursor()
        cursor.execute('SELECT sid FROM LikedTweets WHERE fingerprint = ?', values)

        found = cursor.fetchone()

        return found is None


    def save_liked_status(self, sid, username, content):
        """Remember a given liked status."""

        fingerprint = self._compute_content_fingerprint(content)

        timestamp = int(time.time())

        values = (sid, username, fingerprint, timestamp, False)

        cursor = self._db.cursor()
        cursor.execute('INSERT INTO LikedTweets VALUES (?, ?, ?, ?, ?)', values)
        self._db.commit()


    def purge_old_status(self):
        """Purge old seen statuses."""

        timestamp = int(time.time()) - max_age * 24 * 60 * 60

        values = (timestamp, False)

        cursor = self._db.cursor()
        cursor.execute('SELECT sid FROM LikedTweets WHERE timestamp < ? AND purged = ?', values)

        rows = cursor.fetchall()

        for row in rows:

            sid = row[0]

            try:

                self._api.destroy_favorite(sid)

            # tweepy.error.TweepError: [{'code': 144, 'message': 'No status found with that ID.'}]
            except tweepy.error.TweepError as err:

                pass

            values = (True, sid)

            cursor = self._db.cursor()
            cursor.execute('UPDATE LikedTweets SET purged = ? WHERE sid = ?', values)

        self._db.commit()

        print('Purged %d liked Tweet%s!' % (len(rows), '' if len(rows) <= 1 else 's'))