/**
 * 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
 * <p>
 * http://www.apache.org/licenses/LICENSE-2.0
 * <p>
 * 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.odpi.specs.runtime.hive;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;

import org.apache.commons.exec.CommandLine;
import org.apache.commons.exec.DefaultExecuteResultHandler;
import org.apache.commons.exec.DefaultExecutor;
import org.apache.commons.exec.ExecuteException;
import org.apache.commons.exec.ExecuteWatchdog;
import org.apache.commons.exec.Executor;
import org.apache.commons.exec.PumpStreamHandler;
import org.apache.commons.exec.environment.EnvironmentUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

public class HiveHelper {
	
	private static final Log LOG = LogFactory.getLog(HiveHelper.class.getName());

	public static Map<String, String> execCommand(CommandLine commandline) {
		return execCommand(commandline, null);
	}

	public static Map<String, String> execCommand(CommandLine commandline,
																								Map<String, String> envVars) {
		
		System.out.println("Executing command:");
		System.out.println(commandline.toString());
		Map<String, String> env = null;
		Map<String, String> entry = new HashMap<String, String>();
		try {
			env = EnvironmentUtils.getProcEnvironment();
		} catch (IOException e1) {
			// TODO Auto-generated catch block
			LOG.debug("Failed to get process environment: "+ e1.getMessage());
			e1.printStackTrace();
		}
		if (envVars != null) {
			for (String key : envVars.keySet()) {
				env.put(key, envVars.get(key));
			}
		}

		DefaultExecuteResultHandler resultHandler = new DefaultExecuteResultHandler();
		ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
		PumpStreamHandler streamHandler = new PumpStreamHandler(outputStream);
		ExecuteWatchdog watchdog = new ExecuteWatchdog(60*10000);
		Executor executor = new DefaultExecutor();
		executor.setExitValue(1);
		executor.setWatchdog(watchdog);
		executor.setStreamHandler(streamHandler);
		try {
			executor.execute(commandline, env, resultHandler);
		} catch (ExecuteException e) {
			// TODO Auto-generated catch block
			LOG.debug("Failed to execute command with exit value: "+ String.valueOf(resultHandler.getExitValue()));
			LOG.debug("outputStream: "+ outputStream.toString());
			entry.put("exitValue", String.valueOf(resultHandler.getExitValue()));
			entry.put("outputStream", outputStream.toString() + e.getMessage());
			e.printStackTrace();
			return entry;
		} catch (IOException e) {
			// TODO Auto-generated catch block
			LOG.debug("Failed to execute command with exit value: "+ String.valueOf(resultHandler.getExitValue()));
			LOG.debug("outputStream: "+ outputStream.toString());
			entry.put("exitValue", String.valueOf(resultHandler.getExitValue()));
			entry.put("outputStream", outputStream.toString() + e.getMessage());
			e.printStackTrace();
			return entry;
		}
		
		try {
			resultHandler.waitFor();
			/*System.out.println("Command output: "+outputStream.toString());*/
			entry.put("exitValue", String.valueOf(resultHandler.getExitValue()));
			entry.put("outputStream", outputStream.toString());
			return entry;
		} catch (InterruptedException e) {
			// TODO Auto-generated catch block
			/*System.out.println("Command output: "+outputStream.toString());*/
			LOG.debug("exitValue: "+ String.valueOf(resultHandler.getExitValue()));
			LOG.debug("outputStream: "+ outputStream.toString());
			entry.put("exitValue", String.valueOf(resultHandler.getExitValue()));
			entry.put("outputStream", outputStream.toString());
			e.printStackTrace();		
			return entry;
		}
	}
	
	protected static String getProperty(String property, String description) {
		String val = System.getProperty(property);
		if (val == null) {
			throw new RuntimeException("You must set the property " + property + " with " +
				description);
		}
		LOG.debug(description + " is " + val);
		return val;
	 }
	

}