/*-
 * ============LICENSE_START=======================================================
 * ECOMP-PAP-REST
 * ================================================================================
 * Copyright (C) 2017 AT&T Intellectual Property. All rights reserved.
 * ================================================================================
 * Licensed 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.
 * ============LICENSE_END=========================================================
 */

package org.openecomp.policy.pap.xacml.rest.components;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.URI;
import java.net.URISyntaxException;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.HashMap;
import java.util.Map;

import javax.json.Json;
import javax.json.JsonReader;

import oasis.names.tc.xacml._3_0.core.schema.wd_17.AttributeDesignatorType;
import oasis.names.tc.xacml._3_0.core.schema.wd_17.AttributeValueType;
import oasis.names.tc.xacml._3_0.core.schema.wd_17.MatchType;
import oasis.names.tc.xacml._3_0.core.schema.wd_17.PolicyType;

import org.apache.commons.io.FilenameUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.json.JSONObject;
import org.openecomp.policy.pap.xacml.rest.adapters.PolicyRestAdapter;
import org.openecomp.policy.rest.XACMLRestProperties;

import org.openecomp.policy.xacml.api.XACMLErrorConstants;
import com.att.research.xacml.std.IdentifierImpl;
import org.openecomp.policy.xacml.util.XACMLPolicyWriter;
import com.att.research.xacml.util.XACMLProperties;
import com.att.research.xacmlatt.pdp.policy.PolicyDef;
import com.att.research.xacmlatt.pdp.policy.dom.DOMPolicyDef;

import org.openecomp.policy.common.logging.eelf.MessageCodes;
import org.openecomp.policy.common.logging.eelf.PolicyLogger;
import org.openecomp.policy.common.logging.flexlogger.FlexLogger; 
import org.openecomp.policy.common.logging.flexlogger.Logger;

public abstract class Policy {

	/**
	 * Common Fields
	 */
	public static final String GET_INT_TYPE = "Integer";
	public static final String GET_STRING_TYPE = "String";

	public static final String ECOMPID = "ECOMPName";
	public static final String CONFIGID = "ConfigName";
	public static final String CLOSEDLOOPID = "ServiceType";
	
	public static final String CONFIG_POLICY = "Config";
	public static final String ACTION_POLICY = "Action";
	public static final String DECISION_POLICY = "Decision";

	protected String policyName = null;
	private static final Logger logger = FlexLogger.getLogger(Policy.class);
	
	boolean isValidForm = true;
	
	private Path finalPolicyPath = null;
	
	private boolean preparedToSave = false;
	
	private boolean policyExists = false;
	
	public Path getFinalPolicyPath() {
		return finalPolicyPath;
	}

	public void setFinalPolicyPath(Path finalPolicyPath) {
		this.finalPolicyPath = finalPolicyPath;
	}

		// Constants Used in XML Creation
		public static final String CATEGORY_RECIPIENT_SUBJECT = "urn:oasis:names:tc:xacml:1.0:subject-category:recipient-subject";
		public static final String CATEGORY_RESOURCE = "urn:oasis:names:tc:xacml:3.0:attribute-category:resource";
		public static final String CATEGORY_ACTION = "urn:oasis:names:tc:xacml:3.0:attribute-category:action";
		public static final String CATEGORY_ACCESS_SUBJECT = "urn:oasis:names:tc:xacml:1.0:subject-category:access-subject";
		public static final String ACTION_ID = "urn:oasis:names:tc:xacml:1.0:action:action-id";
		public static final String SUBJECT_ID = "urn:oasis:names:tc:xacml:1.0:subject:subject-id";
		public static final String RESOURCE_ID = "urn:oasis:names:tc:xacml:1.0:resource:resource-id";
		public static final String FUNTION_INTEGER_ONE_AND_ONLY = "urn:oasis:names:tc:xacml:1.0:function:integer-one-and-only";
		public static final String FUNCTION_STRING_ONE_AND_ONLY = "urn:oasis:names:tc:xacml:1.0:function:string-one-and-only";
		public static final String FUNCTION_BOOLEAN_ONE_AND_ONLY = "urn:oasis:names:tc:xacml:1.0:function:boolean-one-and-only";
		public static final String FUNCTION_STRING_EQUAL = "urn:oasis:names:tc:xacml:1.0:function:string-equal";
		public static final String FUNCTION_STRING_REGEX_MATCH = "org.openecomp.function.regex-match";
		public static final String FUNCTION_STRING_EQUAL_IGNORE = "urn:oasis:names:tc:xacml:3.0:function:string-equal-ignore-case";
		public static final String INTEGER_DATATYPE = "http://www.w3.org/2001/XMLSchema#integer";
		public static final String BOOLEAN_DATATYPE = "http://www.w3.org/2001/XMLSchema#boolean";
		public static final String STRING_DATATYPE = "http://www.w3.org/2001/XMLSchema#string";
		public static final String URI_DATATYPE = "http://www.w3.org/2001/XMLSchema#anyURI";
		public static final String RULE_VARIABLE = "var:";
		public static final String EMPTY_STRING = "";
		private static final String String = null;
		
		public static String CONFIG_HOME = null;
		public static String ACTION_HOME = null;
		public static String CONFIG_URL = null;
		
		protected Map<String, String> performer = new HashMap<String, String>();
		
		private static String actionHome = null;
		private static String configHome = null;

		public PolicyRestAdapter policyAdapter = null;
		String ruleID = "";
		
		public Policy() {
			CONFIG_HOME = getConfigHome();
			ACTION_HOME = getActionHome();
			CONFIG_URL = "$URL";
			performer.put("PDP", "PDPAction");
			performer.put("PEP", "PEPAction");
		}

		//Each policy type seems to either use policyData or data field policy adapter when
		//getting the xml to save the policy. Instead of keep this hardcoded in the save method,
		//this method makes it usable outside.
		/**
		 * Return the data field of the PolicyAdapter that will be used when saving this policy
		 * with the savePolicies method.
		 * @return Either the PolicyAdapter.getData() or PolicyAdapter.getPolicyData()
		 */
		public abstract Object getCorrectPolicyDataObject();
		public abstract Map<String, String>  savePolicies() throws Exception;
		
		//This is the method for preparing the policy for saving.  We have broken it out
		//separately because the fully configured policy is used for multiple things
		public abstract boolean prepareToSave() throws Exception;

		
		// create match for ecomp and config name
		protected MatchType createMatch(String key, String value) {
			MatchType match = new MatchType();

			AttributeValueType attributeValue = new AttributeValueType();
			attributeValue.setDataType(STRING_DATATYPE);
			attributeValue.getContent().add(value);
			match.setAttributeValue(attributeValue);
			AttributeDesignatorType attributeDesignator = new AttributeDesignatorType();
			URI uri = null;
			try {
				uri = new URI(key);
			} catch (URISyntaxException e) {
				e.printStackTrace();
			}
			attributeDesignator.setCategory(CATEGORY_ACCESS_SUBJECT);
			attributeDesignator.setDataType(STRING_DATATYPE);
			attributeDesignator.setAttributeId(new IdentifierImpl(uri).stringValue());
			match.setAttributeDesignator(attributeDesignator);
			match.setMatchId(FUNCTION_STRING_REGEX_MATCH);
			return match;
		}
		
		// Creating the match for dynamically added components.
		protected MatchType createDynamicMatch(String key, String value) {
			MatchType dynamicMatch = new MatchType();
			AttributeValueType dynamicAttributeValue = new AttributeValueType();
			//Attribute attribute = findAttributeByAttributeId(key);
			String dataType = null;
	//		if (value.matches("[0-9]+")) {
	//			dataType = INTEGER_DATATYPE;
	//		} else {
	//			dataType = STRING_DATATYPE;
	//		}
			dataType = STRING_DATATYPE;
			dynamicAttributeValue.setDataType(dataType);
			dynamicAttributeValue.getContent().add(value);
			dynamicMatch.setAttributeValue(dynamicAttributeValue);

			AttributeDesignatorType dynamicAttributeDesignator = new AttributeDesignatorType();

			URI dynamicURI = null;
			try {
				dynamicURI = new URI(key);
			} catch (URISyntaxException e) {
				e.printStackTrace();// log msg
			}
			dynamicAttributeDesignator.setCategory(CATEGORY_RESOURCE);
			dynamicAttributeDesignator.setDataType(dataType);
			dynamicAttributeDesignator.setAttributeId(new IdentifierImpl(dynamicURI).stringValue());
			dynamicMatch.setAttributeDesignator(dynamicAttributeDesignator);
			dynamicMatch.setMatchId(FUNCTION_STRING_REGEX_MATCH);

			return dynamicMatch;
		}

		//validation for numeric
		protected boolean isNumeric(String str)
		{
			for (char c : str.toCharArray())
			{
				if (!Character.isDigit(c)) return false;
			}
			return true;
		}
		
		// Validation for json.
		protected static boolean isJSONValid(String data) {
			try {
				new JSONObject(data);
				InputStream stream = new ByteArrayInputStream(data.getBytes(StandardCharsets.UTF_8));
				JsonReader jsonReader = Json.createReader(stream);
				System.out.println("Json Value is: " + jsonReader.read().toString() );
			} catch (Exception e) {
				return false;
			}
			return true;
		}
		
		//  the Policy Name as Unique One throws error
		protected Path getNextFilename(Path parent, String policyType, String polcyFileName, Integer version) {
			policyType = FilenameUtils.removeExtension(policyType);
			polcyFileName = FilenameUtils.removeExtension(polcyFileName);
			Path newFile = null;
			String policyDir = EMPTY_STRING;
			String absolutePath = parent.toString();
			if (absolutePath != null && !absolutePath.equals(EMPTY_STRING)) {
				policyDir = absolutePath.substring(absolutePath.lastIndexOf("\\") + 1, absolutePath.length());
				if (policyDir == null || policyDir.equals(EMPTY_STRING)) {
					policyDir = absolutePath.substring(absolutePath.lastIndexOf("/") + 1, absolutePath.length());
				}
			}

			String fileName = "default";
			if (policyDir != null && !policyDir.equals(EMPTY_STRING)) {
				fileName = policyType + "_" + String.format(polcyFileName) + "." + version + ".xml";
			} 
			if (fileName != null) {
				newFile = Paths.get(parent.toString(), fileName);
			}
			if (Files.notExists(newFile)) {
				return newFile;
			}
			return null;
		}
		
		protected Path getNextLoopFilename(Path parentPath, String policyType,
				String policyConfigType, String policyFileName, Integer version) {
			policyType = FilenameUtils.removeExtension(policyType);
			policyConfigType = FilenameUtils.removeExtension(policyConfigType);
			policyFileName = FilenameUtils.removeExtension(policyFileName);
			Path newFile = null;
			String policyDir = EMPTY_STRING;
			String absolutePath = parentPath.toString();
			if (absolutePath != null && !absolutePath.equals(EMPTY_STRING)) {
				policyDir = absolutePath.substring(absolutePath.lastIndexOf("\\") + 1, absolutePath.length());
				if (policyDir == null || policyDir.equals(EMPTY_STRING)) {
					policyDir = absolutePath.substring(absolutePath.lastIndexOf("/") + 1, absolutePath.length());
				}
			}

			String fileName = "default";
			if (policyDir != null && !policyDir.equals(EMPTY_STRING)) {
				if(policyConfigType.equals("ClosedLoop_PM")){
					fileName = policyType + "_" + "PM" + "_" +java.lang.String.format(policyFileName) + "." +version +".xml";
				}else if(policyConfigType.equals("ClosedLoop_Fault")){
					fileName = policyType + "_" + "Fault" + "_" +java.lang.String.format(policyFileName) +  "." + version + ".xml";
				}else if(policyConfigType.equals("ClosedLoop_Fault")){
					fileName = policyType + "_" + "Fault" + "_" +java.lang.String.format(policyFileName) +  "." + version + ".xml";
				}else if(policyConfigType.equals("DCAE Micro Service")){
					fileName = policyType + "_" + "MS" + "_" + java.lang.String.format(policyFileName) + "." + version + ".xml";
				}
			} 
			if (fileName != null) {
				newFile = Paths.get(parentPath.toString(), fileName);
			}
			if (Files.notExists(newFile)) {
				return newFile;
			}
			return null;
		}
		
		
		//create policy once all the validations are completed
		protected Map<String, String> createPolicy(final Path policyPath, final Object policyData) {
			Map<String, String> success = new HashMap<String, String>(); 
			//
			// Is the root a PolicySet or Policy?
			//
			
			if (policyData instanceof PolicyType) {
				//
				// Write it out
				//
				//Does not need to be XACMLPolicyWriterWithPapNotify since it is already in the PAP
				//and this transaction is intercepted up stream.
				InputStream inputStream = XACMLPolicyWriter.getXmlAsInputStream((PolicyType) policyData);
				try {
					PolicyDef policyDef = DOMPolicyDef.load(inputStream);
					if (policyDef != null) {
						//This is does not need to be XACMLPolicyWriterWithPapNotification since it is already in the PAP
						//and the transaction was intercepted up stream
						finalPolicyPath = XACMLPolicyWriter.writePolicyFile(policyPath, (PolicyType) policyData);
						this.setFinalPolicyPath(finalPolicyPath);
					} else{
						success.put("validation", "PolicyDef Validation Failed");
					}
				} catch (Exception e) {
					success.put("error", "Validation Failed");
				}
				
			} else {
				//TODO:EELF Cleanup - Remove logger
				//logger.error("Unknown data type sent back.");
				PolicyLogger.error("Unknown data type sent back.");
				return success;
			}
			//
			// Did it get written?
			//
			if (finalPolicyPath == null || !Files.exists(finalPolicyPath)) {
				//TODO:EELF Cleanup - Remove logger
				//logger.error("Failed to write policy file.");
				PolicyLogger.error("Failed to write policy file.");
				return success;
			}
			try {
				success.put("success", "success");
			} finally {
				// vaadin framework will handle exception.
			}
			return success;
		}
		
		public static String getConfigHome(){
			try {
				loadWebapps();
			} catch (Exception e) {
				return null;
			}
			return configHome;
		}
		
		public static String getActionHome(){
			try {
				loadWebapps();
			} catch (Exception e) {
				return null;
			}
			return actionHome;
		}
		
		private static void loadWebapps() throws Exception{
			if(actionHome == null || configHome == null){
				Path webappsPath = Paths.get(XACMLProperties.getProperty(XACMLRestProperties.PROP_PAP_WEBAPPS));
				//Sanity Check
				if (webappsPath == null) {
					//TODO:EELF Cleanup - Remove logger
					//logger.error("Invalid Webapps Path Location property : " + XACMLRestProperties.PROP_PAP_WEBAPPS);
					PolicyLogger.error("Invalid Webapps Path Location property : " + XACMLRestProperties.PROP_PAP_WEBAPPS);
					throw new Exception("Invalid Webapps Path Location property : " + XACMLRestProperties.PROP_PAP_WEBAPPS);
				}
				Path webappsPathConfig;
				Path webappsPathAction;
				if(webappsPath.toString().contains("\\"))
				{
					webappsPathConfig = Paths.get(webappsPath.toString()+"\\Config");
					webappsPathAction = Paths.get(webappsPath.toString()+"\\Action");
				}
				else
				{
					webappsPathConfig = Paths.get(webappsPath.toString()+"/Config");
					webappsPathAction = Paths.get(webappsPath.toString()+"/Action");
				}
				if (Files.notExists(webappsPathConfig)) 
				{
					try {
						Files.createDirectories(webappsPathConfig);
					} catch (IOException e) {
						//TODO:EELF Cleanup - Remove logger
						//logger.error(XACMLErrorConstants.ERROR_PROCESS_FLOW + "Failed to create config directory: "
								//+ webappsPathConfig.toAbsolutePath().toString(), e);
						PolicyLogger.error(MessageCodes.ERROR_PROCESS_FLOW, e, "Policy", "Failed to create config directory");
					}
				}
				if (Files.notExists(webappsPathAction)) 
				{
					try {
						Files.createDirectories(webappsPathAction);
					} catch (IOException e) {
						//TODO:EELF Cleanup - Remove logger
						//logger.error(XACMLErrorConstants.ERROR_PROCESS_FLOW + "Failed to create config directory: "
								//+ webappsPathAction.toAbsolutePath().toString(), e);
						PolicyLogger.error(MessageCodes.ERROR_PROCESS_FLOW, e, "Policy", "Failed to create config directory");
					}
				}
				actionHome = webappsPathAction.toString();
				configHome = webappsPathConfig.toString();
			}
		}
		
		protected String getParentPathSubScopeDir() {

			final Path gitPath = Paths.get(policyAdapter.getUserGitPath().toString());
			String policyDir = policyAdapter.getParentPath().toString();
			int startIndex = policyDir.indexOf(gitPath.toString()) + gitPath.toString().length() + 1;
			policyDir = policyDir.substring(startIndex, policyDir.length());
			
			return policyDir;
		}


		public boolean validateConfigForm() {
			// TODO Auto-generated method stub
			return true;
		}

		/**
		 * @return the preparedToSave
		 */
		public boolean isPreparedToSave() {
			return preparedToSave;
		}

		/**
		 * @param preparedToSave the preparedToSave to set
		 */
		protected void setPreparedToSave(boolean preparedToSave) {
			this.preparedToSave = preparedToSave;
		}

		public boolean isPolicyExists() {
			return policyExists;
		}

		public void setPolicyExists(boolean policyExists) {
			this.policyExists = policyExists;
		}
		
		
}