/*
 *  Licensed to the Apache Software Foundation (ASF) under one or more
 *  contributor license agreements.  See the NOTICE file distributed with
 *  this work for additional information regarding copyright ownership.
 *  The ASF licenses this file to You under the Apache License, Version 2.0
 *  (the "License"); you may not use this file except in compliance with
 *  the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */
package org.apache.tomcat.websocket.pojo;

import java.io.InputStream;
import java.io.Reader;
import java.lang.annotation.Annotation;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.nio.ByteBuffer;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;

import jakarta.websocket.CloseReason;
import jakarta.websocket.DecodeException;
import jakarta.websocket.Decoder;
import jakarta.websocket.DeploymentException;
import jakarta.websocket.EndpointConfig;
import jakarta.websocket.MessageHandler;
import jakarta.websocket.OnClose;
import jakarta.websocket.OnError;
import jakarta.websocket.OnMessage;
import jakarta.websocket.OnOpen;
import jakarta.websocket.PongMessage;
import jakarta.websocket.Session;
import jakarta.websocket.server.PathParam;

import org.apache.tomcat.InstanceManager;
import org.apache.tomcat.util.res.StringManager;
import org.apache.tomcat.websocket.DecoderEntry;
import org.apache.tomcat.websocket.Util;
import org.apache.tomcat.websocket.Util.DecoderMatch;

/**
 * For a POJO class annotated with {@link jakarta.websocket.server.ServerEndpoint}, an instance of this class creates
 * and caches the method handler, method information and parameter information for the onXXX calls.
 */
public class PojoMethodMapping {

    private static final StringManager sm = StringManager.getManager(PojoMethodMapping.class);

    private final Method onOpen;
    private final Method onClose;
    private final Method onError;
    private final PojoPathParam[] onOpenParams;
    private final PojoPathParam[] onCloseParams;
    private final PojoPathParam[] onErrorParams;
    private final List<MessageHandlerInfo> onMessage = new ArrayList<>();
    private final String wsPath;


    /**
     * Create a method mapping for the given POJO
     *
     * @param clazzPojo       POJO implementation class
     * @param decoderClazzes  Set of potential decoder classes
     * @param wsPath          Path at which the endpoint will be deployed
     * @param instanceManager Instance manager to use to create Decoder instances
     *
     * @throws DeploymentException If the mapping cannot be completed
     */
    public PojoMethodMapping(Class<?> clazzPojo, List<Class<? extends Decoder>> decoderClazzes, String wsPath,
            InstanceManager instanceManager) throws DeploymentException {

        this.wsPath = wsPath;

        List<DecoderEntry> decoders = Util.getDecoders(decoderClazzes, instanceManager);
        Method open = null;
        Method close = null;
        Method error = null;
        Method[] clazzPojoMethods = null;
        Class<?> currentClazz = clazzPojo;
        while (!currentClazz.equals(Object.class)) {
            Method[] currentClazzMethods = currentClazz.getDeclaredMethods();
            if (currentClazz == clazzPojo) {
                clazzPojoMethods = currentClazzMethods;
            }
            for (Method method : currentClazzMethods) {
                if (method.isSynthetic()) {
                    // Skip all synthetic methods.
                    // They may have copies of annotations from methods we are
                    // interested in, and they will use the wrong parameter type
                    // (they always use Object) so we can't use them here.
                    continue;
                }
                if (method.getAnnotation(OnOpen.class) != null) {
                    checkPublic(method);
                    if (open == null) {
                        open = method;
                    } else {
                        if (currentClazz == clazzPojo || !isMethodOverride(open, method)) {
                            // Duplicate annotation
                            throw new DeploymentException(
                                    sm.getString("pojoMethodMapping.duplicateAnnotation", OnOpen.class, currentClazz));
                        }
                    }
                } else if (method.getAnnotation(OnClose.class) != null) {
                    checkPublic(method);
                    if (close == null) {
                        close = method;
                    } else {
                        if (currentClazz == clazzPojo || !isMethodOverride(close, method)) {
                            // Duplicate annotation
                            throw new DeploymentException(
                                    sm.getString("pojoMethodMapping.duplicateAnnotation", OnClose.class, currentClazz));
                        }
                    }
                } else if (method.getAnnotation(OnError.class) != null) {
                    checkPublic(method);
                    if (error == null) {
                        error = method;
                    } else {
                        if (currentClazz == clazzPojo || !isMethodOverride(error, method)) {
                            // Duplicate annotation
                            throw new DeploymentException(
                                    sm.getString("pojoMethodMapping.duplicateAnnotation", OnError.class, currentClazz));
                        }
                    }
                } else if (method.getAnnotation(OnMessage.class) != null) {
                    checkPublic(method);
                    MessageHandlerInfo messageHandler = new MessageHandlerInfo(method, decoders);
                    boolean found = false;
                    for (MessageHandlerInfo otherMessageHandler : onMessage) {
                        if (messageHandler.targetsSameWebSocketMessageType(otherMessageHandler)) {
                            found = true;
                            if (currentClazz == clazzPojo ||
                                    !isMethodOverride(messageHandler.m, otherMessageHandler.m)) {
                                // Duplicate annotation
                                throw new DeploymentException(sm.getString("pojoMethodMapping.duplicateAnnotation",
                                        OnMessage.class, currentClazz));
                            }
                        }
                    }
                    if (!found) {
                        onMessage.add(messageHandler);
                    }
                } else {
                    // Method not annotated
                }
            }
            currentClazz = currentClazz.getSuperclass();
        }
        // If the methods are not on clazzPojo, and they are overridden
        // by a non annotated method in clazzPojo, they should be ignored
        if (open != null && open.getDeclaringClass() != clazzPojo) {
            if (isOverridenWithoutAnnotation(clazzPojoMethods, open, OnOpen.class)) {
                open = null;
            }
        }
        if (close != null && close.getDeclaringClass() != clazzPojo) {
            if (isOverridenWithoutAnnotation(clazzPojoMethods, close, OnClose.class)) {
                close = null;
            }
        }
        if (error != null && error.getDeclaringClass() != clazzPojo) {
            if (isOverridenWithoutAnnotation(clazzPojoMethods, error, OnError.class)) {
                error = null;
            }
        }
        List<MessageHandlerInfo> overriddenOnMessage = new ArrayList<>();
        for (MessageHandlerInfo messageHandler : onMessage) {
            if (messageHandler.m.getDeclaringClass() != clazzPojo &&
                    isOverridenWithoutAnnotation(clazzPojoMethods, messageHandler.m, OnMessage.class)) {
                overriddenOnMessage.add(messageHandler);
            }
        }
        for (MessageHandlerInfo messageHandler : overriddenOnMessage) {
            onMessage.remove(messageHandler);
        }
        this.onOpen = open;
        this.onClose = close;
        this.onError = error;
        onOpenParams = getPathParams(onOpen, MethodType.ON_OPEN);
        onCloseParams = getPathParams(onClose, MethodType.ON_CLOSE);
        onErrorParams = getPathParams(onError, MethodType.ON_ERROR);
    }


    private void checkPublic(Method m) throws DeploymentException {
        if (!Modifier.isPublic(m.getModifiers())) {
            throw new DeploymentException(sm.getString("pojoMethodMapping.methodNotPublic", m.getName()));
        }
    }


    private boolean isMethodOverride(Method method1, Method method2) {
        return method1.getName().equals(method2.getName()) && method1.getReturnType().equals(method2.getReturnType()) &&
                Arrays.equals(method1.getParameterTypes(), method2.getParameterTypes());
    }


    private boolean isOverridenWithoutAnnotation(Method[] methods, Method superclazzMethod,
            Class<? extends Annotation> annotation) {
        for (Method method : methods) {
            if (isMethodOverride(method, superclazzMethod) && (method.getAnnotation(annotation) == null)) {
                return true;
            }
        }
        return false;
    }


    public String getWsPath() {
        return wsPath;
    }


    public Method getOnOpen() {
        return onOpen;
    }


    public Object[] getOnOpenArgs(Map<String, String> pathParameters, Session session, EndpointConfig config)
            throws DecodeException {
        return buildArgs(onOpenParams, pathParameters, session, config, null, null);
    }


    public Method getOnClose() {
        return onClose;
    }


    public Object[] getOnCloseArgs(Map<String, String> pathParameters, Session session, CloseReason closeReason)
            throws DecodeException {
        return buildArgs(onCloseParams, pathParameters, session, null, null, closeReason);
    }


    public Method getOnError() {
        return onError;
    }


    public Object[] getOnErrorArgs(Map<String, String> pathParameters, Session session, Throwable throwable)
            throws DecodeException {
        return buildArgs(onErrorParams, pathParameters, session, null, throwable, null);
    }


    public boolean hasMessageHandlers() {
        return !onMessage.isEmpty();
    }


    public Set<MessageHandler> getMessageHandlers(Object pojo, Map<String, String> pathParameters, Session session,
            EndpointConfig config) {
        Set<MessageHandler> result = new HashSet<>();
        for (MessageHandlerInfo messageMethod : onMessage) {
            result.addAll(messageMethod.getMessageHandlers(pojo, pathParameters, session, config));
        }
        return result;
    }


    private static PojoPathParam[] getPathParams(Method m, MethodType methodType) throws DeploymentException {
        if (m == null) {
            return new PojoPathParam[0];
        }
        boolean foundThrowable = false;
        Class<?>[] types = m.getParameterTypes();
        Annotation[][] paramsAnnotations = m.getParameterAnnotations();
        PojoPathParam[] result = new PojoPathParam[types.length];
        for (int i = 0; i < types.length; i++) {
            Class<?> type = types[i];
            if (type.equals(Session.class)) {
                result[i] = new PojoPathParam(type, null);
            } else if (methodType == MethodType.ON_OPEN && type.equals(EndpointConfig.class)) {
                result[i] = new PojoPathParam(type, null);
            } else if (methodType == MethodType.ON_ERROR && type.equals(Throwable.class)) {
                foundThrowable = true;
                result[i] = new PojoPathParam(type, null);
            } else if (methodType == MethodType.ON_CLOSE && type.equals(CloseReason.class)) {
                result[i] = new PojoPathParam(type, null);
            } else {
                Annotation[] paramAnnotations = paramsAnnotations[i];
                for (Annotation paramAnnotation : paramAnnotations) {
                    if (paramAnnotation.annotationType().equals(PathParam.class)) {
                        result[i] = new PojoPathParam(type, ((PathParam) paramAnnotation).value());
                        break;
                    }
                }
                // Parameters without annotations are not permitted
                if (result[i] == null) {
                    throw new DeploymentException(sm.getString("pojoMethodMapping.paramWithoutAnnotation", type,
                            m.getName(), m.getClass().getName()));
                }
            }
        }
        if (methodType == MethodType.ON_ERROR && !foundThrowable) {
            throw new DeploymentException(
                    sm.getString("pojoMethodMapping.onErrorNoThrowable", m.getName(), m.getDeclaringClass().getName()));
        }
        return result;
    }


    private static Object[] buildArgs(PojoPathParam[] pathParams, Map<String, String> pathParameters, Session session,
            EndpointConfig config, Throwable throwable, CloseReason closeReason) throws DecodeException {
        Object[] result = new Object[pathParams.length];
        for (int i = 0; i < pathParams.length; i++) {
            Class<?> type = pathParams[i].getType();
            if (type.equals(Session.class)) {
                result[i] = session;
            } else if (type.equals(EndpointConfig.class)) {
                result[i] = config;
            } else if (type.equals(Throwable.class)) {
                result[i] = throwable;
            } else if (type.equals(CloseReason.class)) {
                result[i] = closeReason;
            } else {
                String name = pathParams[i].getName();
                String value = pathParameters.get(name);
                try {
                    result[i] = Util.coerceToType(type, value);
                } catch (Exception e) {
                    throw new DecodeException(value, sm.getString("pojoMethodMapping.decodePathParamFail", value, type),
                            e);
                }
            }
        }
        return result;
    }


    private static class MessageHandlerInfo {

        private final Method m;
        private int indexString = -1;
        private int indexByteArray = -1;
        private int indexByteBuffer = -1;
        private int indexPong = -1;
        private int indexBoolean = -1;
        private int indexSession = -1;
        private int indexInputStream = -1;
        private int indexReader = -1;
        private int indexPrimitive = -1;
        private final Map<Integer, PojoPathParam> indexPathParams = new HashMap<>();
        private int indexPayload = -1;
        private DecoderMatch decoderMatch = null;
        private final long maxMessageSize;

        MessageHandlerInfo(Method m, List<DecoderEntry> decoderEntries) throws DeploymentException {

            this.m = m;

            Class<?>[] types = m.getParameterTypes();
            Annotation[][] paramsAnnotations = m.getParameterAnnotations();

            for (int i = 0; i < types.length; i++) {
                boolean paramFound = false;
                Annotation[] paramAnnotations = paramsAnnotations[i];
                for (Annotation paramAnnotation : paramAnnotations) {
                    if (paramAnnotation.annotationType().equals(PathParam.class)) {
                        indexPathParams.put(Integer.valueOf(i),
                                new PojoPathParam(types[i], ((PathParam) paramAnnotation).value()));
                        paramFound = true;
                        break;
                    }
                }
                if (paramFound) {
                    continue;
                }
                if (String.class.isAssignableFrom(types[i])) {
                    if (indexString == -1) {
                        indexString = i;
                    } else {
                        throw new DeploymentException(sm.getString("pojoMethodMapping.duplicateMessageParam",
                                m.getName(), m.getDeclaringClass().getName()));
                    }
                } else if (Reader.class.isAssignableFrom(types[i])) {
                    if (indexReader == -1) {
                        indexReader = i;
                    } else {
                        throw new DeploymentException(sm.getString("pojoMethodMapping.duplicateMessageParam",
                                m.getName(), m.getDeclaringClass().getName()));
                    }
                } else if (boolean.class == types[i]) {
                    if (indexBoolean == -1) {
                        indexBoolean = i;
                    } else {
                        throw new DeploymentException(sm.getString("pojoMethodMapping.duplicateLastParam", m.getName(),
                                m.getDeclaringClass().getName()));
                    }
                } else if (ByteBuffer.class.isAssignableFrom(types[i])) {
                    if (indexByteBuffer == -1) {
                        indexByteBuffer = i;
                    } else {
                        throw new DeploymentException(sm.getString("pojoMethodMapping.duplicateMessageParam",
                                m.getName(), m.getDeclaringClass().getName()));
                    }
                } else if (byte[].class == types[i]) {
                    if (indexByteArray == -1) {
                        indexByteArray = i;
                    } else {
                        throw new DeploymentException(sm.getString("pojoMethodMapping.duplicateMessageParam",
                                m.getName(), m.getDeclaringClass().getName()));
                    }
                } else if (InputStream.class.isAssignableFrom(types[i])) {
                    if (indexInputStream == -1) {
                        indexInputStream = i;
                    } else {
                        throw new DeploymentException(sm.getString("pojoMethodMapping.duplicateMessageParam",
                                m.getName(), m.getDeclaringClass().getName()));
                    }
                } else if (Util.isPrimitive(types[i])) {
                    if (indexPrimitive == -1) {
                        indexPrimitive = i;
                    } else {
                        throw new DeploymentException(sm.getString("pojoMethodMapping.duplicateMessageParam",
                                m.getName(), m.getDeclaringClass().getName()));
                    }
                } else if (Session.class.isAssignableFrom(types[i])) {
                    if (indexSession == -1) {
                        indexSession = i;
                    } else {
                        throw new DeploymentException(sm.getString("pojoMethodMapping.duplicateSessionParam",
                                m.getName(), m.getDeclaringClass().getName()));
                    }
                } else if (PongMessage.class.isAssignableFrom(types[i])) {
                    if (indexPong == -1) {
                        indexPong = i;
                    } else {
                        throw new DeploymentException(sm.getString("pojoMethodMapping.duplicatePongMessageParam",
                                m.getName(), m.getDeclaringClass().getName()));
                    }
                } else {
                    if (decoderMatch != null && decoderMatch.hasMatches()) {
                        throw new DeploymentException(sm.getString("pojoMethodMapping.duplicateMessageParam",
                                m.getName(), m.getDeclaringClass().getName()));
                    }
                    decoderMatch = new DecoderMatch(types[i], decoderEntries);

                    if (decoderMatch.hasMatches()) {
                        indexPayload = i;
                    } else {
                        throw new DeploymentException(sm.getString("pojoMethodMapping.noDecoder", m.getName(),
                                m.getDeclaringClass().getName()));
                    }
                }
            }

            // Additional checks required
            if (indexString != -1) {
                if (indexPayload != -1) {
                    throw new DeploymentException(sm.getString("pojoMethodMapping.duplicateMessageParam", m.getName(),
                            m.getDeclaringClass().getName()));
                } else {
                    indexPayload = indexString;
                }
            }
            if (indexReader != -1) {
                if (indexPayload != -1) {
                    throw new DeploymentException(sm.getString("pojoMethodMapping.duplicateMessageParam", m.getName(),
                            m.getDeclaringClass().getName()));
                } else {
                    indexPayload = indexReader;
                }
            }
            if (indexByteArray != -1) {
                if (indexPayload != -1) {
                    throw new DeploymentException(sm.getString("pojoMethodMapping.duplicateMessageParam", m.getName(),
                            m.getDeclaringClass().getName()));
                } else {
                    indexPayload = indexByteArray;
                }
            }
            if (indexByteBuffer != -1) {
                if (indexPayload != -1) {
                    throw new DeploymentException(sm.getString("pojoMethodMapping.duplicateMessageParam", m.getName(),
                            m.getDeclaringClass().getName()));
                } else {
                    indexPayload = indexByteBuffer;
                }
            }
            if (indexInputStream != -1) {
                if (indexPayload != -1) {
                    throw new DeploymentException(sm.getString("pojoMethodMapping.duplicateMessageParam", m.getName(),
                            m.getDeclaringClass().getName()));
                } else {
                    indexPayload = indexInputStream;
                }
            }
            if (indexPrimitive != -1) {
                if (indexPayload != -1) {
                    throw new DeploymentException(sm.getString("pojoMethodMapping.duplicateMessageParam", m.getName(),
                            m.getDeclaringClass().getName()));
                } else {
                    indexPayload = indexPrimitive;
                }
            }
            if (indexPong != -1) {
                if (indexPayload != -1) {
                    throw new DeploymentException(sm.getString("pojoMethodMapping.pongWithPayload", m.getName(),
                            m.getDeclaringClass().getName()));
                } else {
                    indexPayload = indexPong;
                }
            }
            if (indexPayload == -1 && indexPrimitive == -1 && indexBoolean != -1) {
                // The boolean we found is a payload, not a last flag
                indexPayload = indexBoolean;
                indexPrimitive = indexBoolean;
                indexBoolean = -1;
            }
            if (indexPayload == -1) {
                throw new DeploymentException(
                        sm.getString("pojoMethodMapping.noPayload", m.getName(), m.getDeclaringClass().getName()));
            }
            if (indexPong != -1 && indexBoolean != -1) {
                throw new DeploymentException(
                        sm.getString("pojoMethodMapping.partialPong", m.getName(), m.getDeclaringClass().getName()));
            }
            if (indexReader != -1 && indexBoolean != -1) {
                throw new DeploymentException(
                        sm.getString("pojoMethodMapping.partialReader", m.getName(), m.getDeclaringClass().getName()));
            }
            if (indexInputStream != -1 && indexBoolean != -1) {
                throw new DeploymentException(sm.getString("pojoMethodMapping.partialInputStream", m.getName(),
                        m.getDeclaringClass().getName()));
            }
            if (decoderMatch != null && decoderMatch.hasMatches() && indexBoolean != -1) {
                throw new DeploymentException(
                        sm.getString("pojoMethodMapping.partialObject", m.getName(), m.getDeclaringClass().getName()));
            }

            maxMessageSize = m.getAnnotation(OnMessage.class).maxMessageSize();
        }


        public boolean targetsSameWebSocketMessageType(MessageHandlerInfo otherHandler) {
            if (otherHandler == null) {
                return false;
            }

            return isPong() && otherHandler.isPong() || isBinary() && otherHandler.isBinary() ||
                    isText() && otherHandler.isText();
        }


        private boolean isPong() {
            return indexPong >= 0;
        }


        private boolean isText() {
            return indexString >= 0 || indexPrimitive >= 0 || indexReader >= 0 ||
                    (decoderMatch != null && !decoderMatch.getTextDecoders().isEmpty());
        }


        private boolean isBinary() {
            return indexByteArray >= 0 || indexByteBuffer >= 0 || indexInputStream >= 0 ||
                    (decoderMatch != null && !decoderMatch.getBinaryDecoders().isEmpty());
        }


        public Set<MessageHandler> getMessageHandlers(Object pojo, Map<String, String> pathParameters, Session session,
                EndpointConfig config) {
            Object[] params = new Object[m.getParameterTypes().length];

            for (Map.Entry<Integer, PojoPathParam> entry : indexPathParams.entrySet()) {
                PojoPathParam pathParam = entry.getValue();
                String valueString = pathParameters.get(pathParam.getName());
                Object value;
                try {
                    value = Util.coerceToType(pathParam.getType(), valueString);
                } catch (Exception e) {
                    DecodeException de = new DecodeException(valueString,
                            sm.getString("pojoMethodMapping.decodePathParamFail", valueString, pathParam.getType()), e);
                    params = new Object[] { de };
                    break;
                }
                params[entry.getKey().intValue()] = value;
            }

            Set<MessageHandler> results = new HashSet<>(2);
            if (indexBoolean == -1) {
                // Basic
                if (indexString != -1 || indexPrimitive != -1) {
                    MessageHandler mh = new PojoMessageHandlerWholeText(pojo, m, session, config, null, params,
                            indexPayload, false, indexSession, maxMessageSize);
                    results.add(mh);
                } else if (indexReader != -1) {
                    MessageHandler mh = new PojoMessageHandlerWholeText(pojo, m, session, config, null, params,
                            indexReader, true, indexSession, maxMessageSize);
                    results.add(mh);
                } else if (indexByteArray != -1) {
                    MessageHandler mh = new PojoMessageHandlerWholeBinary(pojo, m, session, config, null, params,
                            indexByteArray, true, indexSession, false, maxMessageSize);
                    results.add(mh);
                } else if (indexByteBuffer != -1) {
                    MessageHandler mh = new PojoMessageHandlerWholeBinary(pojo, m, session, config, null, params,
                            indexByteBuffer, false, indexSession, false, maxMessageSize);
                    results.add(mh);
                } else if (indexInputStream != -1) {
                    MessageHandler mh = new PojoMessageHandlerWholeBinary(pojo, m, session, config, null, params,
                            indexInputStream, true, indexSession, true, maxMessageSize);
                    results.add(mh);
                } else if (decoderMatch != null && decoderMatch.hasMatches()) {
                    if (!decoderMatch.getBinaryDecoders().isEmpty()) {
                        MessageHandler mh = new PojoMessageHandlerWholeBinary(pojo, m, session, config,
                                decoderMatch.getBinaryDecoders(), params, indexPayload, true, indexSession, true,
                                maxMessageSize);
                        results.add(mh);
                    }
                    if (!decoderMatch.getTextDecoders().isEmpty()) {
                        MessageHandler mh = new PojoMessageHandlerWholeText(pojo, m, session, config,
                                decoderMatch.getTextDecoders(), params, indexPayload, true, indexSession,
                                maxMessageSize);
                        results.add(mh);
                    }
                } else {
                    MessageHandler mh = new PojoMessageHandlerWholePong(pojo, m, session, params, indexPong, false,
                            indexSession);
                    results.add(mh);
                }
            } else {
                // ASync
                if (indexString != -1) {
                    MessageHandler mh = new PojoMessageHandlerPartialText(pojo, m, session, params, indexString, false,
                            indexBoolean, indexSession, maxMessageSize);
                    results.add(mh);
                } else if (indexByteArray != -1) {
                    MessageHandler mh = new PojoMessageHandlerPartialBinary(pojo, m, session, params, indexByteArray,
                            true, indexBoolean, indexSession, maxMessageSize);
                    results.add(mh);
                } else {
                    MessageHandler mh = new PojoMessageHandlerPartialBinary(pojo, m, session, params, indexByteBuffer,
                            false, indexBoolean, indexSession, maxMessageSize);
                    results.add(mh);
                }
            }
            return results;
        }
    }


    private enum MethodType {
        ON_OPEN,
        ON_CLOSE,
        ON_ERROR
    }
}
