/*
 * 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.geode.internal.cache.tier.sockets.command;

import java.io.IOException;
import java.util.HashSet;
import java.util.Optional;
import java.util.Set;

import org.apache.geode.cache.Region;
import org.apache.geode.cache.execute.Function;
import org.apache.geode.cache.execute.FunctionException;
import org.apache.geode.cache.execute.FunctionService;
import org.apache.geode.cache.operations.ExecuteFunctionOperationContext;
import org.apache.geode.internal.cache.DistributedRegion;
import org.apache.geode.internal.cache.PartitionedRegion;
import org.apache.geode.internal.cache.execute.AbstractExecution;
import org.apache.geode.internal.cache.execute.DistributedRegionFunctionExecutor;
import org.apache.geode.internal.cache.execute.InternalFunctionInvocationTargetException;
import org.apache.geode.internal.cache.execute.MemberMappedArgument;
import org.apache.geode.internal.cache.execute.PartitionedRegionFunctionExecutor;
import org.apache.geode.internal.cache.execute.ServerToClientFunctionResultSender;
import org.apache.geode.internal.cache.tier.CachedRegionHelper;
import org.apache.geode.internal.cache.tier.Command;
import org.apache.geode.internal.cache.tier.MessageType;
import org.apache.geode.internal.cache.tier.sockets.BaseCommand;
import org.apache.geode.internal.cache.tier.sockets.ChunkedMessage;
import org.apache.geode.internal.cache.tier.sockets.HandShake;
import org.apache.geode.internal.cache.tier.sockets.Message;
import org.apache.geode.internal.cache.tier.sockets.Part;
import org.apache.geode.internal.cache.tier.sockets.ServerConnection;
import org.apache.geode.internal.i18n.LocalizedStrings;
import org.apache.geode.internal.logging.log4j.LocalizedMessage;
import org.apache.geode.internal.security.AuthorizeRequest;
import org.apache.geode.internal.security.SecurityService;

/**
 * This is the base command which reads the parts for the MessageType.EXECUTE_REGION_FUNCTION and
 * executes the given function on server region.<br>
 * If the hasResult byte is 1, then this command send back the result after the execution to the
 * client else do not send the reply back to the client
 *
 * @since GemFire 5.8LA
 */
public class ExecuteRegionFunction extends BaseCommand {

  private final static ExecuteRegionFunction singleton = new ExecuteRegionFunction();

  public static Command getCommand() {
    return singleton;
  }

  private ExecuteRegionFunction() {}

  @Override
  public void cmdExecute(final Message clientMessage, final ServerConnection serverConnection,
      final SecurityService securityService, long start) throws IOException {
    String regionName = null;
    Object function = null;
    Object args = null;
    MemberMappedArgument memberMappedArg = null;
    Set filter = null;
    byte hasResult = 0;
    int filterSize = 0, partNumber = 0;
    CachedRegionHelper crHelper = serverConnection.getCachedRegionHelper();
    try {
      hasResult = clientMessage.getPart(0).getSerializedForm()[0];
      if (hasResult == 1) {
        serverConnection.setAsTrue(REQUIRES_RESPONSE);
        serverConnection.setAsTrue(REQUIRES_CHUNKED_RESPONSE);
      }
      regionName = clientMessage.getPart(1).getString();
      function = clientMessage.getPart(2).getStringOrObject();
      args = clientMessage.getPart(3).getObject();
      Part part = clientMessage.getPart(4);
      if (part != null) {
        Object obj = part.getObject();
        if (obj instanceof MemberMappedArgument) {
          memberMappedArg = (MemberMappedArgument) obj;
        }
      }
      filterSize = clientMessage.getPart(5).getInt();
      if (filterSize != 0) {
        filter = new HashSet();
        partNumber = 6;
        for (int i = 0; i < filterSize; i++) {
          filter.add(clientMessage.getPart(partNumber + i).getStringOrObject());
        }
      }

    } catch (ClassNotFoundException exception) {
      logger.warn(LocalizedMessage.create(
          LocalizedStrings.ExecuteRegionFunction_EXCEPTION_ON_SERVER_WHILE_EXECUTIONG_FUNCTION_0,
          function), exception);
      if (hasResult == 1) {
        writeChunkedException(clientMessage, exception, serverConnection);
        serverConnection.setAsTrue(RESPONDED);
        return;
      }
    }
    if (function == null || regionName == null) {
      String message = null;
      if (function == null) {
        message =
            LocalizedStrings.ExecuteRegionFunction_THE_INPUT_0_FOR_THE_EXECUTE_FUNCTION_REQUEST_IS_NULL
                .toLocalizedString("function");
      }
      if (regionName == null) {
        message =
            LocalizedStrings.ExecuteRegionFunction_THE_INPUT_0_FOR_THE_EXECUTE_FUNCTION_REQUEST_IS_NULL
                .toLocalizedString("region");
      }
      logger.warn("{}: {}", serverConnection.getName(), message);
      sendError(hasResult, clientMessage, message, serverConnection);
      return;
    }

    Region region = crHelper.getRegion(regionName);
    if (region == null) {
      String message =
          LocalizedStrings.ExecuteRegionFunction_THE_REGION_NAMED_0_WAS_NOT_FOUND_DURING_EXECUTE_FUNCTION_REQUEST
              .toLocalizedString(regionName);
      logger.warn("{}: {}", serverConnection.getName(), message);
      sendError(hasResult, clientMessage, message, serverConnection);
      return;
    }

    HandShake handShake = (HandShake) serverConnection.getHandshake();
    int earlierClientReadTimeout = handShake.getClientReadTimeout();
    handShake.setClientReadTimeout(0);
    ServerToClientFunctionResultSender resultSender = null;
    Function<?> functionObject = null;
    try {
      if (function instanceof String) {
        functionObject = FunctionService.getFunction((String) function);
        if (functionObject == null) {
          String message =
              LocalizedStrings.ExecuteRegionFunction_THE_FUNCTION_0_HAS_NOT_BEEN_REGISTERED
                  .toLocalizedString(function);
          logger.warn("{}: {}", serverConnection.getName(), message);
          sendError(hasResult, clientMessage, message, serverConnection);
          return;
        }
      } else {
        functionObject = (Function) function;
      }

      // check if the caller is authorized to do this operation on server
      functionObject.getRequiredPermissions(regionName).forEach(securityService::authorize);
      AuthorizeRequest authzRequest = serverConnection.getAuthzRequest();
      final String functionName = functionObject.getId();
      final String regionPath = region.getFullPath();
      ExecuteFunctionOperationContext executeContext = null;
      if (authzRequest != null) {
        executeContext = authzRequest.executeFunctionAuthorize(functionName, regionPath, filter,
            args, functionObject.optimizeForWrite());
      }

      // Construct execution
      AbstractExecution execution = (AbstractExecution) FunctionService.onRegion(region);
      ChunkedMessage m = serverConnection.getFunctionResponseMessage();
      m.setTransactionId(clientMessage.getTransactionId());
      resultSender =
          new ServerToClientFunctionResultSender(m, MessageType.EXECUTE_REGION_FUNCTION_RESULT,
              serverConnection, functionObject, executeContext);

      if (execution instanceof PartitionedRegionFunctionExecutor) {
        execution = new PartitionedRegionFunctionExecutor((PartitionedRegion) region, filter, args,
            memberMappedArg, resultSender, null, false);
      } else {
        execution = new DistributedRegionFunctionExecutor((DistributedRegion) region, filter, args,
            memberMappedArg, resultSender);
      }

      if (logger.isDebugEnabled()) {
        logger.debug("Executing Function: {} on Server: {} with Execution: {}",
            functionObject.getId(), serverConnection, execution);
      }
      if (hasResult == 1) {
        if (function instanceof String) {
          execution.execute((String) function).getResult();
        } else {
          execution.execute(functionObject).getResult();
        }
      } else {
        if (function instanceof String) {
          execution.execute((String) function);
        } else {
          execution.execute(functionObject);
        }
      }
    } catch (IOException ioe) {
      logger.warn(LocalizedMessage.create(
          LocalizedStrings.ExecuteRegionFunction_EXCEPTION_ON_SERVER_WHILE_EXECUTIONG_FUNCTION_0,
          function), ioe);
      final String message = LocalizedStrings.ExecuteRegionFunction_SERVER_COULD_NOT_SEND_THE_REPLY
          .toLocalizedString();
      sendException(hasResult, clientMessage, message, serverConnection, ioe);
    } catch (InternalFunctionInvocationTargetException internalfunctionException) {
      // Fix for #44709: User should not be aware of
      // InternalFunctionInvocationTargetException. No instance of
      // InternalFunctionInvocationTargetException is giving useful
      // information to user to take any corrective action hence logging
      // this at fine level logging
      // 1> When bucket is moved
      // 2> Incase of HA FucntionInvocationTargetException thrown. Since
      // it is HA, fucntion will be reexecuted on right node
      // 3> Multiple target nodes found for single hop operation
      // 4> in case of HA member departed
      if (logger.isDebugEnabled()) {
        logger.debug(LocalizedMessage.create(
            LocalizedStrings.ExecuteFunction_EXCEPTION_ON_SERVER_WHILE_EXECUTIONG_FUNCTION_0,
            new Object[] {function}), internalfunctionException);
      }
      final String message = internalfunctionException.getMessage();
      sendException(hasResult, clientMessage, message, serverConnection, internalfunctionException);
    } catch (FunctionException fe) {
      logger.warn(LocalizedMessage.create(
          LocalizedStrings.ExecuteRegionFunction_EXCEPTION_ON_SERVER_WHILE_EXECUTIONG_FUNCTION_0,
          function), fe);
      String message = fe.getMessage();

      sendException(hasResult, clientMessage, message, serverConnection, fe);
    } catch (Exception e) {
      logger.warn(LocalizedMessage.create(
          LocalizedStrings.ExecuteRegionFunction_EXCEPTION_ON_SERVER_WHILE_EXECUTIONG_FUNCTION_0,
          function), e);
      String message = e.getMessage();
      sendException(hasResult, clientMessage, message, serverConnection, e);
    } finally {
      handShake.setClientReadTimeout(earlierClientReadTimeout);
    }
  }

  private void sendException(byte hasResult, Message msg, String message,
      ServerConnection serverConnection, Throwable e) throws IOException {
    synchronized (msg) {
      if (hasResult == 1) {
        writeFunctionResponseException(msg, MessageType.EXCEPTION, serverConnection, e);
        serverConnection.setAsTrue(RESPONDED);
      }
    }
  }

  private void sendError(byte hasResult, Message msg, String message,
      ServerConnection serverConnection) throws IOException {
    synchronized (msg) {
      if (hasResult == 1) {
        writeFunctionResponseError(msg, MessageType.EXECUTE_REGION_FUNCTION_ERROR, message,
            serverConnection);
        serverConnection.setAsTrue(RESPONDED);
      }
    }
  }
}
