package org.thoughtcrime.securesms.database;

import android.content.Context;

import androidx.annotation.NonNull;

import com.annimon.stream.Stream;

import net.sqlcipher.Cursor;
import net.sqlcipher.database.SQLiteDatabase;

import org.session.libsession.utilities.Util;
import org.thoughtcrime.securesms.database.helpers.SQLCipherOpenHelper;

import java.util.List;

/**
 * Contains all databases necessary for full-text search (FTS).
 */
public class SearchDatabase extends Database {

  public static final String SMS_FTS_TABLE_NAME = "sms_fts";
  public static final String MMS_FTS_TABLE_NAME = "mms_fts";

  public static final String ID                   = "rowid";
  public static final String BODY                 = MmsSmsColumns.BODY;
  public static final String THREAD_ID            = MmsSmsColumns.THREAD_ID;
  public static final String SNIPPET              = "snippet";
  public static final String CONVERSATION_ADDRESS = "conversation_address";
  public static final String MESSAGE_ADDRESS      = "message_address";

  public static final String[] CREATE_TABLE = {
      "CREATE VIRTUAL TABLE " + SMS_FTS_TABLE_NAME + " USING fts5(" + BODY + ", " + THREAD_ID + " UNINDEXED, content=" + SmsDatabase.TABLE_NAME + ", content_rowid=" + SmsDatabase.ID + ");",

      "CREATE TRIGGER sms_ai AFTER INSERT ON " + SmsDatabase.TABLE_NAME + " BEGIN\n" +
          "  INSERT INTO " + SMS_FTS_TABLE_NAME + "(" + ID + ", " + BODY + ", " + THREAD_ID + ") VALUES (new." + SmsDatabase.ID + ", new." + SmsDatabase.BODY + ", new." + SmsDatabase.THREAD_ID + ");\n" +
          "END;\n",
      "CREATE TRIGGER sms_ad AFTER DELETE ON " + SmsDatabase.TABLE_NAME + " BEGIN\n" +
          "  INSERT INTO " + SMS_FTS_TABLE_NAME + "(" + SMS_FTS_TABLE_NAME + ", " + ID + ", " + BODY + ", " + THREAD_ID + ") VALUES('delete', old." + SmsDatabase.ID + ", old." + SmsDatabase.BODY + ", old." + SmsDatabase.THREAD_ID + ");\n" +
          "END;\n",
      "CREATE TRIGGER sms_au AFTER UPDATE ON " + SmsDatabase.TABLE_NAME + " BEGIN\n" +
          "  INSERT INTO " + SMS_FTS_TABLE_NAME + "(" + SMS_FTS_TABLE_NAME + ", " + ID + ", " + BODY + ", " + THREAD_ID + ") VALUES('delete', old." + SmsDatabase.ID + ", old." + SmsDatabase.BODY + ", old." + SmsDatabase.THREAD_ID + ");\n" +
          "  INSERT INTO " + SMS_FTS_TABLE_NAME + "(" + ID + ", " + BODY + ", " + THREAD_ID + ") VALUES(new." + SmsDatabase.ID + ", new." + SmsDatabase.BODY + ", new." + SmsDatabase.THREAD_ID + ");\n" +
          "END;",


      "CREATE VIRTUAL TABLE " + MMS_FTS_TABLE_NAME + " USING fts5(" + BODY + ", " + THREAD_ID + " UNINDEXED, content=" + MmsDatabase.TABLE_NAME + ", content_rowid=" + MmsDatabase.ID + ");",

      "CREATE TRIGGER mms_ai AFTER INSERT ON " + MmsDatabase.TABLE_NAME + " BEGIN\n" +
          "  INSERT INTO " + MMS_FTS_TABLE_NAME + "(" + ID + ", " + BODY + ", " + THREAD_ID + ") VALUES (new." + MmsDatabase.ID + ", new." + MmsDatabase.BODY + ", new." + MmsDatabase.THREAD_ID + ");\n" +
          "END;\n",
      "CREATE TRIGGER mms_ad AFTER DELETE ON " + MmsDatabase.TABLE_NAME + " BEGIN\n" +
          "  INSERT INTO " + MMS_FTS_TABLE_NAME + "(" + MMS_FTS_TABLE_NAME + ", " + ID + ", " + BODY + ", " + THREAD_ID + ") VALUES('delete', old." + MmsDatabase.ID + ", old." + MmsDatabase.BODY + ", old." + MmsDatabase.THREAD_ID + ");\n" +
          "END;\n",
      "CREATE TRIGGER mms_au AFTER UPDATE ON " + MmsDatabase.TABLE_NAME + " BEGIN\n" +
          "  INSERT INTO " + MMS_FTS_TABLE_NAME + "(" + MMS_FTS_TABLE_NAME + ", " + ID + ", " + BODY + ", " + THREAD_ID + ") VALUES('delete', old." + MmsDatabase.ID + ", old." + MmsDatabase.BODY + ", old." + MmsDatabase.THREAD_ID + ");\n" +
          "  INSERT INTO " + MMS_FTS_TABLE_NAME + "(" + ID + ", " + BODY + ", " + THREAD_ID + ") VALUES (new." + MmsDatabase.ID + ", new." + MmsDatabase.BODY + ", new." + MmsDatabase.THREAD_ID + ");\n" +
          "END;"
  };

  private static final String MESSAGES_QUERY =
      "SELECT " +
        ThreadDatabase.TABLE_NAME + "." + ThreadDatabase.ADDRESS + " AS " + CONVERSATION_ADDRESS + ", " +
        MmsSmsColumns.ADDRESS + " AS " + MESSAGE_ADDRESS + ", " +
        "snippet(" + SMS_FTS_TABLE_NAME + ", -1, '', '', '...', 7) AS " + SNIPPET + ", " +
        SmsDatabase.TABLE_NAME + "." + SmsDatabase.DATE_RECEIVED + " AS " + MmsSmsColumns.NORMALIZED_DATE_RECEIVED + ", " +
        SMS_FTS_TABLE_NAME + "."  + THREAD_ID + " " +
      "FROM " + SmsDatabase.TABLE_NAME + " " +
      "INNER JOIN " + SMS_FTS_TABLE_NAME + " ON " + SMS_FTS_TABLE_NAME + "." + ID + " = " + SmsDatabase.TABLE_NAME + "." + SmsDatabase.ID + " " +
      "INNER JOIN " + ThreadDatabase.TABLE_NAME + " ON " + SMS_FTS_TABLE_NAME + "." + THREAD_ID + " = " + ThreadDatabase.TABLE_NAME + "." + ThreadDatabase.ID + " " +
      "WHERE " + SMS_FTS_TABLE_NAME + " MATCH ? " +
      "UNION ALL " +
      "SELECT " +
        ThreadDatabase.TABLE_NAME + "." + ThreadDatabase.ADDRESS + " AS " + CONVERSATION_ADDRESS + ", " +
        MmsSmsColumns.ADDRESS + " AS " + MESSAGE_ADDRESS + ", " +
        "snippet(" + MMS_FTS_TABLE_NAME + ", -1, '', '', '...', 7) AS " + SNIPPET + ", " +
        MmsDatabase.TABLE_NAME + "." + MmsDatabase.DATE_RECEIVED + " AS " + MmsSmsColumns.NORMALIZED_DATE_RECEIVED + ", " +
        MMS_FTS_TABLE_NAME + "." + THREAD_ID + " " +
      "FROM " + MmsDatabase.TABLE_NAME + " " +
      "INNER JOIN " + MMS_FTS_TABLE_NAME + " ON " + MMS_FTS_TABLE_NAME + "." + ID + " = " + MmsDatabase.TABLE_NAME + "." + MmsDatabase.ID + " " +
      "INNER JOIN " + ThreadDatabase.TABLE_NAME + " ON " + MMS_FTS_TABLE_NAME + "." + THREAD_ID + " = " + ThreadDatabase.TABLE_NAME + "." + ThreadDatabase.ID + " " +
      "WHERE " + MMS_FTS_TABLE_NAME + " MATCH ? " +
      "ORDER BY " + MmsSmsColumns.NORMALIZED_DATE_RECEIVED + " DESC " +
      "LIMIT ?";

  private static final String MESSAGES_FOR_THREAD_QUERY =
      "SELECT " +
          ThreadDatabase.TABLE_NAME + "." + ThreadDatabase.ADDRESS + " AS " + CONVERSATION_ADDRESS + ", " +
          MmsSmsColumns.ADDRESS + " AS " + MESSAGE_ADDRESS + ", " +
          "snippet(" + SMS_FTS_TABLE_NAME + ", -1, '', '', '...', 7) AS " + SNIPPET + ", " +
          SmsDatabase.TABLE_NAME + "." + SmsDatabase.DATE_RECEIVED + " AS " + MmsSmsColumns.NORMALIZED_DATE_RECEIVED + ", " +
          SMS_FTS_TABLE_NAME + "." + THREAD_ID + " " +
        "FROM " + SmsDatabase.TABLE_NAME + " " +
        "INNER JOIN " + SMS_FTS_TABLE_NAME + " ON " + SMS_FTS_TABLE_NAME + "." + ID + " = " + SmsDatabase.TABLE_NAME + "." + SmsDatabase.ID + " " +
        "INNER JOIN " + ThreadDatabase.TABLE_NAME + " ON " + SMS_FTS_TABLE_NAME + "." + THREAD_ID + " = " + ThreadDatabase.TABLE_NAME + "." + ThreadDatabase.ID + " " +
        "WHERE " + SMS_FTS_TABLE_NAME + " MATCH ? AND " + SmsDatabase.TABLE_NAME + "." + MmsSmsColumns.THREAD_ID + " = ? " +
        "UNION ALL " +
        "SELECT " +
          ThreadDatabase.TABLE_NAME + "." + ThreadDatabase.ADDRESS + " AS " + CONVERSATION_ADDRESS + ", " +
          MmsSmsColumns.ADDRESS + " AS " + MESSAGE_ADDRESS + ", " +
          "snippet(" + MMS_FTS_TABLE_NAME + ", -1, '', '', '...', 7) AS " + SNIPPET + ", " +
          MmsDatabase.TABLE_NAME + "." + MmsDatabase.DATE_RECEIVED + " AS " + MmsSmsColumns.NORMALIZED_DATE_RECEIVED + ", " +
          MMS_FTS_TABLE_NAME + "." + THREAD_ID + " " +
        "FROM " + MmsDatabase.TABLE_NAME + " " +
        "INNER JOIN " + MMS_FTS_TABLE_NAME + " ON " + MMS_FTS_TABLE_NAME + "." + ID + " = " + MmsDatabase.TABLE_NAME + "." + MmsDatabase.ID + " " +
        "INNER JOIN " + ThreadDatabase.TABLE_NAME + " ON " + MMS_FTS_TABLE_NAME + "." + THREAD_ID + " = " + ThreadDatabase.TABLE_NAME + "." + ThreadDatabase.ID + " " +
        "WHERE " + MMS_FTS_TABLE_NAME + " MATCH ? AND " + MmsDatabase.TABLE_NAME + "." + MmsSmsColumns.THREAD_ID + " = ? " +
        "ORDER BY " + MmsSmsColumns.NORMALIZED_DATE_RECEIVED + " DESC " +
        "LIMIT 500";

  public SearchDatabase(@NonNull Context context, @NonNull SQLCipherOpenHelper databaseHelper) {
    super(context, databaseHelper);
  }

  public Cursor queryMessages(@NonNull String query) {
    SQLiteDatabase db          = databaseHelper.getReadableDatabase();
    String         prefixQuery = adjustQuery(query);

    int queryLimit = Math.min(query.length()*50,500);

    Cursor cursor = db.rawQuery(MESSAGES_QUERY, new String[] { prefixQuery, prefixQuery, String.valueOf(queryLimit) });
    setNotifyConverationListListeners(cursor);
    return cursor;
  }

  public Cursor queryMessages(@NonNull String query, long threadId) {
    SQLiteDatabase db          = databaseHelper.getReadableDatabase();
    String         prefixQuery = adjustQuery(query);

    Cursor cursor = db.rawQuery(MESSAGES_FOR_THREAD_QUERY, new String[] { prefixQuery, String.valueOf(threadId), prefixQuery, String.valueOf(threadId) });
    setNotifyConverationListListeners(cursor);
    return cursor;

  }

  private String adjustQuery(@NonNull String query) {
    List<String> tokens      = Stream.of(query.split(" ")).filter(s -> s.trim().length() > 0).toList();
    String       prefixQuery = Util.join(tokens, "* ");

    prefixQuery += "*";

    return prefixQuery;
  }
}