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//      Magicbane Emulator Project © 2013 - 2022
//                www.magicbane.com


package engine.db.handlers;

import engine.Enum;
import engine.Enum.GameObjectType;
import engine.gameManager.ConfigManager;
import engine.gameManager.DbManager;
import engine.objects.AbstractGameObject;
import engine.objects.AbstractWorldObject;
import engine.server.MBServerStatics;
import org.pmw.tinylog.Logger;

import java.sql.*;
import java.time.LocalDateTime;
import java.util.ArrayList;
import java.util.HashSet;

public abstract class dbHandlerBase {

	/*
	 * CallableStatements handled below this line!
	 */
	protected Class<? extends AbstractGameObject> localClass = null;
	protected GameObjectType localObjectType;
	protected final ThreadLocal<CallableStatement> callableStatement = new ThreadLocal<>();
	protected final ThreadLocal<Connection> connection = new ThreadLocal<>();

	protected final void prepareCallable(final String sql) {
		try {
			this.connection.set(DbManager.getConnection());
			this.callableStatement.set(this.connection.get().prepareCall(sql, ResultSet.TYPE_FORWARD_ONLY, ResultSet.CONCUR_READ_ONLY));
		} catch (SQLException e) {
			Logger.error("DbManager.getConn", e);
			Logger.error("SQL Error number: " + e.getErrorCode());
		}
	}

	protected final void setInt(int parameterIndex, int value) {
		try {
			this.callableStatement.get().setInt(parameterIndex, value);
		} catch (SQLException e) {
			Logger.error("SQL Error number: " + e.getErrorCode());
		}
	}

	protected final void setLong(int parameterIndex, long value) {
		try {
			this.callableStatement.get().setLong(parameterIndex, value);
		} catch (SQLException e) {
			Logger.error("SQL Error number: " + e.getErrorCode());
		}
	}

	protected final void setFloat(int parameterIndex, float value) {
		try {
			this.callableStatement.get().setFloat(parameterIndex, value);
		} catch (SQLException e) {
			Logger.error("SQL Error number: " + e.getErrorCode());
		}
	}

	protected final void setShort(int parameterIndex, short value) {
		try {
			this.callableStatement.get().setShort(parameterIndex, value);
		} catch (SQLException e) {
			Logger.error("SQL Error number: " + e.getErrorCode());
		}
	}

	protected final void setString(int parameterIndex, String value) {
		try {
			this.callableStatement.get().setString(parameterIndex, value);
		} catch (SQLException e) {
			Logger.error("SQL Error number: " + e.getErrorCode());
		}
	}

	protected final void setByte(int parameterIndex, byte value) {
		try {
			this.callableStatement.get().setByte(parameterIndex, value);
		} catch (SQLException e) {
			Logger.error("SQL Error number: " + e.getErrorCode());
		}
	}

	protected final void setBoolean(int parameterIndex, boolean value) {
		try {
			this.callableStatement.get().setBoolean(parameterIndex, value);
		} catch (SQLException e) {
			Logger.error("SQL Error number: " + e.getErrorCode());
		}
	}

	protected final void setNULL(int parameterIndex, int type) {
		try {
			this.callableStatement.get().setNull(parameterIndex, type);
		} catch (SQLException e) {
			Logger.error("SQL Error number: " + e.getErrorCode());
		}
	}

	protected final void setLocalDateTime(int parameterIndex, LocalDateTime localDateTime) {

		try {
			this.callableStatement.get().setTimestamp(parameterIndex, Timestamp.valueOf(localDateTime));
		} catch (SQLException e) {
			Logger.error("SQL Error number: " + e.getErrorCode());
		}
	}

	protected final void setTimeStamp(int parameterIndex, long time) {
		try {
			this.callableStatement.get().setTimestamp(parameterIndex, new java.sql.Timestamp(time));
		} catch (SQLException e) {
			Logger.error("SQL Error number: " + e.getErrorCode());
		}
	}

	protected final boolean execute() {
		try {
			return this.callableStatement.get().execute();
		} catch (SQLException e) {
			Logger.error("SQL Error number: " + e.getErrorCode());
			logSQLCommand();
		}
		return false;
	}

	protected final ResultSet executeQuery() {
		try {
			return this.callableStatement.get().executeQuery();
		} catch (SQLException e) {
			Logger.error("SQL Error number: " + e.getErrorCode());
			logSQLCommand();
		}
		return null;
	}

	protected final int executeUpdate() {
		return executeUpdate(true);
	}

	protected final int executeUpdate(boolean close) {
		try {
			return this.callableStatement.get().executeUpdate();
		} catch (SQLException e) {
			Logger.error("SQL Error number: " + e.getErrorCode());
			logSQLCommand();
		} finally {
			if (close)
				closeCallable();
		}
		return 0;
	}

	protected final void logSQLCommand() {
		try {
			Logger.error("Failed SQL Command: " + this.callableStatement.get().toString());
		} catch (Exception e) {

		}
	}

	// Common return values from the database when calling stored procedures, abstracted to this layer
	protected final String getResult(){
		try {
			ResultSet rs = this.executeQuery();
			if (rs.next() && !isError(rs))
				return rs.getString("result");
		} catch (SQLException e) {
			Logger.error(e);
			logSQLCommand();
		} finally {
			closeCallable();
		}
		return null;
	}

	// Used for Stored procedures that return true when they succeed.
	protected final boolean worked() {
		try {
			ResultSet rs = this.executeQuery();
			if (rs.next() && !isError(rs))
				return rs.getBoolean("result");
		} catch (SQLException e) {
			Logger.error(e);
			logSQLCommand();
		} finally {
			closeCallable();
		}
		return false;
	}

	// Common return values from the database when calling stored procedures, abstracted to this layer
	protected final long getUUID(){
		try {
			ResultSet rs = this.executeQuery();
			if (rs.next() && !isError(rs))
				return rs.getLong("UID");
		} catch (SQLException e) {
			Logger.error(e);
			logSQLCommand();
		} finally {
			closeCallable();
		}
		return -1;
	}

	protected final String getString(String field) {
		try {
			ResultSet rs = this.executeQuery();
			if (rs.next())
				return rs.getString(field);
		} catch (SQLException e) {
			Logger.error(e);
			logSQLCommand();
		} finally {
			closeCallable();
		}
		return "";
	}

	protected final long getLong(String field) {
		try {
			ResultSet rs = this.executeQuery();
			if (rs.next())
				return rs.getLong(field);
		} catch (SQLException e) {
			Logger.error(e);
			logSQLCommand();
		} finally {
			closeCallable();
		}
		return 0L;
	}

	protected final int getInt(String field) {
		try {
			ResultSet rs = this.executeQuery();
			if (rs.next())
				return rs.getInt(field);
		} catch (SQLException e) {
			Logger.error(e);
			logSQLCommand();
		} finally {
			closeCallable();
		}
		return 0;
	}

	protected final int insertGetUUID() {
		int key = 0;
		try {
			this.callableStatement.get().executeUpdate();
			ResultSet rs = this.callableStatement.get().getGeneratedKeys();
			if (rs.next())
				key = rs.getInt(1);
		} catch (SQLException e) {
			Logger.error(e);
			logSQLCommand();
		} finally {
			closeCallable();
		}
		return key;
	}

	protected final boolean isError(ResultSet rs) throws SQLException {
		ResultSetMetaData rsmd = rs.getMetaData();
		if (rsmd.getColumnCount() > 0 && !rsmd.getColumnName(1).equals("errorno"))
			return false;
		printError(rs);
		return true;
	}

	protected final void printError(ResultSet rs) {
		try {
			int errorNum = rs.getInt("errorno");
			String errorMsg = rs.getString("errormsg");
			Logger.error("SQLError: errorNum: " + errorNum + ", errorMsg: " + errorMsg);
			logSQLCommand();
		} catch (SQLException e) {}
	}

	protected <T extends AbstractGameObject> AbstractGameObject getObjectSingle(int id) {
		return getObjectSingle(id, false, true);
	}

	protected <T extends AbstractGameObject> AbstractGameObject getObjectSingle(int id, boolean forceFromDB, boolean storeInCache) {

		if (callableStatement.get() == null) {
			return null;
		}

		if (!forceFromDB) {
			if (DbManager.inCache(localObjectType, id)) {
				closeCallable();
				return DbManager.getFromCache(localObjectType, id);
			}
		}

		AbstractGameObject out = null;

		try {
			if (MBServerStatics.DB_ENABLE_QUERY_OUTPUT)
				Logger.info("[GetObjectList] Executing query:" + callableStatement.get().toString());

			ResultSet rs = callableStatement.get().executeQuery();

			if (rs.next()) {
				out = localClass.getConstructor(ResultSet.class).newInstance(rs);

				if (storeInCache)
					DbManager.addToCache(out);
			}

			rs.close();

		} catch (Exception e) {
			Logger.error("AbstractGameObject", e);
			out = null;
		} finally {
			closeCallable();
		}

		// Only call runAfterLoad() for objects instanced on the world server

		if ((out != null && out instanceof AbstractWorldObject) &&
				(ConfigManager.serverType.equals(Enum.ServerType.WORLDSERVER) ||
						(out.getObjectType() == GameObjectType.Guild)))
			((AbstractWorldObject)out).runAfterLoad();

		return out;
	}

	protected void closeCallable() {
		try {
			if (this.callableStatement.get() != null)
				this.callableStatement.get().close();

			this.connection.get().close();

		} catch (SQLException e) {}
	}

	protected <T extends AbstractGameObject> ArrayList<T> getObjectList() {
		return getObjectList(20, false);
	}

	protected <T extends AbstractGameObject> ArrayList<T> getLargeObjectList() {
		return getObjectList(2000, false);
	}

	@SuppressWarnings("unchecked")
	protected <T extends AbstractGameObject> ArrayList<T> getObjectList(int listSize, boolean forceFromDB) {

		String query = "No Callable Statement accessable.";

		ArrayList<T> out = new ArrayList<>(listSize);

		if (this.callableStatement.get() == null)
			return out;

		try {

			CallableStatement css = this.callableStatement.get();

			if (css != null)
				query = this.callableStatement.get().toString();

			if (MBServerStatics.DB_ENABLE_QUERY_OUTPUT)
				Logger.info( "[GetObjectList] Executing query:" + query);

			ResultSet rs = this.callableStatement.get().executeQuery();

			while (rs.next()) {

				int id = rs.getInt(1);

				if (!forceFromDB && DbManager.inCache(localObjectType, id)) {
					out.add((T) DbManager.getFromCache(localObjectType, id));
				} else {
					AbstractGameObject toAdd = localClass.getConstructor(ResultSet.class).newInstance(rs);
					DbManager.addToCache(toAdd);
					out.add((T) toAdd);

					if (toAdd != null && toAdd instanceof AbstractWorldObject)
						((AbstractWorldObject)toAdd).runAfterLoad();

				}
			}
			rs.close();
		} catch (Exception e) {
			Logger.error(localClass.getCanonicalName(), "List Failure: " + query, e);
			e.printStackTrace();
			return new ArrayList<>(); // Do we want a null return on error?
		} finally {
			closeCallable();
		}

		return out;
	}

	/* Prepared Statements handled below this line */

	protected HashSet<Integer> getIntegerList(final int columnNumber) {

		if (MBServerStatics.DB_ENABLE_QUERY_OUTPUT)
			Logger.info("[GetIntegerList] Executing query:" + this.callableStatement.toString());

		HashSet<Integer> out = new HashSet<>();

		try {
			ResultSet rs = executeQuery();

			while (rs.next()) {
				out.add(rs.getInt(columnNumber));
			}
			rs.close();
		} catch (SQLException e) {
			Logger.error("SQL Error number: " + e.getErrorCode());
		} finally {
			closeCallable();
		}
		return out;
	}
}