package main;

import data.Tweet;
import data.User;
import database.NamedPreparedStatement;
import database.QueryUtils;
import java.sql.Connection;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;

/**
 * Process that incoming tweets and fill the database.
 *
 * @author Maurice Laveaux
 */
public class DataFiller {

    /**
     * The main database connection to fill.
     */
    private final Connection m_connection;

    private final NamedPreparedStatement m_insertTweet;
    private final NamedPreparedStatement m_insertProfile;
    private final NamedPreparedStatement m_insertBrand;
    private final NamedPreparedStatement m_insertHash;
    private final NamedPreparedStatement m_insertTweetUrl;
    private final NamedPreparedStatement m_insertUserUrl;
    private final NamedPreparedStatement m_insertMentions;

    private final int m_category;
    
    /**
     * Create the datafiller object.
     *
     * @param connection The database connection to use.
     * @throws java.sql.SQLException on error preparing the database connection.
     */
    public DataFiller(Connection connection, int category) throws SQLException {
        m_category = category;
        m_connection = connection;
        m_insertTweet = new NamedPreparedStatement(m_connection, QueryUtils.insertTweet);
        m_insertProfile = new NamedPreparedStatement(m_connection, QueryUtils.insertProfile);
        m_insertBrand = new NamedPreparedStatement(m_connection, QueryUtils.insertBrand);
        m_insertHash = new NamedPreparedStatement(m_connection, QueryUtils.insertHash);
        m_insertTweetUrl = new NamedPreparedStatement(m_connection, QueryUtils.insertTweetUrl);
        m_insertUserUrl = new NamedPreparedStatement(m_connection, QueryUtils.insertUserUrl);
        m_insertMentions = new NamedPreparedStatement(m_connection, QueryUtils.insertMentions);
        // enable transactions
        connection.setAutoCommit(false);
    }

    /**
     * Replaces three HTML entities ('&', '<', '>') by their normal
     * forms. Later, this might also strip useless characters.
     *
     * @param text The tweet message.
     * @return A sanitized form of the tweet text.
     */
    private String sanitizeTweetText(String text) {
        // sample tweets, 12k contained '&amp', 2.6k '>' and 300 '<'.
        // Note: time_zone, description, expanded_url, location are unaffected.
        return text
                .replaceAll("&lt;", "<")
                .replaceAll("&gt;", ">")
                .replaceAll("&amp;", "&");
    }

    public void processTweet(Tweet tweet) throws SQLException {
        // process retweets first because of the foreign key.
        if (tweet.retweeted_status != null) {
            processTweet(tweet.retweeted_status);
        }

        /**
         * Replace all null bytes, non valid UTF-8 *
         */
        if (tweet.text.contains("\0")) {
            tweet.text = tweet.text.replaceAll("\0", "");
        }
        
        User user = tweet.user;
        
        if (user.name.contains("\0")) {
            user.name = user.name.replaceAll("\0", "");
        }
        

        try {
            // assume that no previous transaction was started.
            saveTweet(tweet);
            // concludes the previous query, implicitly starts a new transaction
            m_connection.commit();
        } catch (Exception ex) {
            m_connection.rollback();
            throw ex;
        }
    }

    private void saveTweet(Tweet tweet) throws SQLException {
        String text = sanitizeTweetText(tweet.text);

        // ensure that the user and tweet are known before adding relations
        m_insertTweet.setInt("category", m_category);
        QueryUtils.setInsertParams(m_insertTweet, m_insertProfile, tweet, text);
        m_insertProfile.executeUpdate();
        m_insertTweet.executeUpdate();

        for (Tweet.Hashtag hashtag : tweet.entities.hashtags) {
            m_insertHash.setLong("tweetid", tweet.id);
            m_insertHash.setString("hashtag", hashtag.text);
            m_insertHash.executeUpdate();
        }
        for (Tweet.Url url : tweet.entities.urls) {
            m_insertTweetUrl.setLong("tweetid", tweet.id);
            m_insertTweetUrl.setString("url", url.expanded_url);
            m_insertTweetUrl.executeUpdate();
        }
        for (Tweet.Mention mention : tweet.entities.user_mentions) {
            m_insertMentions.setLong("tweetid", tweet.id);
            m_insertMentions.setLong("userid", mention.id);
            m_insertMentions.executeUpdate();
        }

        User user = tweet.user;
        if (user.entities != null) {
            for (Tweet.Url url : tweet.entities.urls) {
                m_insertUserUrl.setLong("userid", user.id);
                m_insertUserUrl.setString("url", url.expanded_url);
                m_insertUserUrl.executeUpdate();
            }
        }

        // determine the user's perception of the brand
        /*
         List<String> brands = getBrands(tweet);
         for (String brand : brands) {
         QueryUtils.setInsertBrandParams(m_insertBrand, tweet.id, brand);
         m_insertBrand.executeUpdate();
         }
         */
    }
}