/*
 * Juick
 * Copyright (C) 2008-2011, Ugnich Anton
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package com.juick.server;

import com.juick.Tag;
import org.apache.commons.lang3.StringEscapeUtils;
import org.springframework.dao.EmptyResultDataAccessException;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.support.GeneratedKeyHolder;
import org.springframework.jdbc.support.KeyHolder;

import java.sql.PreparedStatement;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.util.stream.Collectors;

/**
 *
 * @author Ugnich Anton
 */
public class TagQueries {

    public static com.juick.Tag getTag(JdbcTemplate sql, int tid) {
        try {
            return sql.queryForObject("SELECT synonym_id,name FROM tags WHERE tag_id=?",
                    (rs, num) -> {
                        Tag ret = new Tag(StringEscapeUtils.unescapeHtml4(rs.getString(2)));
                        ret.TID = tid;
                        ret.SynonymID = rs.getInt(1);
                        return ret;
                    }, tid);
        } catch (EmptyResultDataAccessException e) {
            return null;
        }
    }

    public static com.juick.Tag getTag(JdbcTemplate sql, String tag, boolean autoCreate) {
        Tag ret = null;
        try {
            ret = sql.queryForObject("SELECT tag_id,synonym_id,name FROM tags WHERE name=?",
                    (rs, rowNum) -> {
                        Tag ret1 = new Tag(StringEscapeUtils.unescapeHtml4(rs.getString(3)));
                        ret1.TID = rs.getInt(1);
                        ret1.SynonymID = rs.getInt(2);
                        return ret1;
                    }, StringEscapeUtils.escapeHtml4(tag));
        } catch (EmptyResultDataAccessException e) {
            // tag not found
        }
        if (ret == null && autoCreate) {
            ret = new com.juick.Tag(tag);
            ret.TID = createTag(sql, tag);
        }

        return ret;
    }

    public static List<com.juick.Tag> getTags(JdbcTemplate sql, String[] tags, boolean autoCreate) {
        List<Tag> ret = new ArrayList<>();

        for (String tag : tags) {
            if (!tag.isEmpty()) {
                Tag t = getTag(sql, tag, autoCreate);
                if (t != null) {
                    ret.add(t);
                }
            }
        }

        return ret;
    }

    public static boolean getTagNoIndex(JdbcTemplate sql, int tag_id) {
        try {
            return sql.queryForObject("SELECT noindex FROM tags WHERE tag_id=?", Integer.class, tag_id) == 1;
        } catch (EmptyResultDataAccessException e) {
            return false;
        }
    }

    public static int createTag(JdbcTemplate sql, String name) {
        KeyHolder holder = new GeneratedKeyHolder();
        sql.update(con -> {
            PreparedStatement stmt = con.prepareStatement("INSERT INTO tags(name) VALUES (?)",
                    Statement.RETURN_GENERATED_KEYS);
                stmt.setString(1, StringEscapeUtils.escapeHtml4(name));
                return stmt;
        }, holder);

        return holder.getKey().intValue();
    }

    public static List<com.juick.Tag> getUserTagsAll(JdbcTemplate sql, int uid) {
        return sql.query("SELECT tags.name,COUNT(messages.message_id) " +
                        "FROM (messages INNER JOIN messages_tags ON (messages.user_id=? " +
                        "AND messages.message_id=messages_tags.message_id)) " +
                        "INNER JOIN tags ON messages_tags.tag_id=tags.tag_id GROUP BY tags.tag_id ORDER BY tags.name ASC",
                (rs, rowNum) -> {
                    Tag t = new Tag(StringEscapeUtils.unescapeHtml4(rs.getString(1)));
                    t.UsageCnt = rs.getInt(2);
                    return t;
                }, uid);
    }

    public static List<String> getUserBLTags(JdbcTemplate sql, int uid) {
        return sql.queryForList("SELECT tags.name FROM tags INNER JOIN bl_tags " +
                        "ON (bl_tags.user_id=? AND bl_tags.tag_id=tags.tag_id) ORDER BY tags.name",
                String.class, uid);
    }

    public static List<String> getPopularTags(JdbcTemplate sql) {
        return sql.queryForList("SELECT name FROM tags WHERE top=1 ORDER BY name ASC", String.class).stream()
                .map(StringEscapeUtils::unescapeHtml4).collect(Collectors.toList());
    }
    public static List<Tag> updateTags(JdbcTemplate sql, int mid, List<Tag> newTags) {
        List<Tag> currentTags = MessagesQueries.getMessageTags(sql, mid);
        newTags.stream().filter(currentTags::contains)
                .forEach(t -> sql.update("DELETE FROM messages_tags WHERE message_id=? AND tag_id=?", mid, t.TID));
        newTags.stream().filter(t -> !currentTags.contains(t))
                .forEach(t -> sql.update("INSERT INTO messages_tags(message_id,tag_id) VALUES (?,?)", mid, t.TID));
        return MessagesQueries.getMessageTags(sql, mid);
    }

    public static List<Tag> fromString(JdbcTemplate sql, String txt, boolean tagsOnly) {
        String patternString = tagsOnly ? "^(?:(?:\\*[^ \\r\\n\\t]+)|\\s)+$" : "^\\*([^ \\r\\n\\t]+)\\s+([\\s\\S]+)";
        Pattern tagsPattern = Pattern.compile(patternString);
        if (tagsPattern.matcher(txt).matches()) {
            Pattern tagPattern = Pattern.compile("\\*([^ \\r\\n\\t]+)");
            Matcher tagMatcher = tagPattern.matcher(txt);
            List<Tag> tags = new ArrayList<>();
            // TODO: process readonly, private, friends, public
            while (tagMatcher.find()) {
                for (int i = 1; i <= tagMatcher.groupCount(); i++) {
                    tags.add(getTag(sql, tagMatcher.group(i), true));
                }
            }
            return tags;
        }
        return Collections.emptyList();
    }
}