/*-
 * ============LICENSE_START=======================================================
 * ONAP-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.onap.policy.pap.xacml.rest.components;

import java.io.BufferedWriter;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;

import javax.persistence.EntityManager;
import javax.persistence.Query;

import oasis.names.tc.xacml._3_0.core.schema.wd_17.AllOfType;
import oasis.names.tc.xacml._3_0.core.schema.wd_17.AnyOfType;
import oasis.names.tc.xacml._3_0.core.schema.wd_17.ApplyType;
import oasis.names.tc.xacml._3_0.core.schema.wd_17.AttributeAssignmentExpressionType;
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.ConditionType;
import oasis.names.tc.xacml._3_0.core.schema.wd_17.EffectType;
import oasis.names.tc.xacml._3_0.core.schema.wd_17.MatchType;
import oasis.names.tc.xacml._3_0.core.schema.wd_17.ObjectFactory;
import oasis.names.tc.xacml._3_0.core.schema.wd_17.ObligationExpressionType;
import oasis.names.tc.xacml._3_0.core.schema.wd_17.ObligationExpressionsType;
import oasis.names.tc.xacml._3_0.core.schema.wd_17.PolicyType;
import oasis.names.tc.xacml._3_0.core.schema.wd_17.RuleType;
import oasis.names.tc.xacml._3_0.core.schema.wd_17.TargetType;

import org.onap.policy.pap.xacml.rest.XACMLPapServlet;
import org.onap.policy.pap.xacml.rest.util.JPAUtils;
import org.onap.policy.rest.adapter.PolicyRestAdapter;
import org.onap.policy.rest.jpa.ActionPolicyDict;
import org.onap.policy.rest.jpa.Datatype;
import org.onap.policy.rest.jpa.FunctionDefinition;
import org.onap.policy.xacml.api.XACMLErrorConstants;
import org.onap.policy.common.logging.eelf.MessageCodes;
import org.onap.policy.common.logging.eelf.PolicyLogger;
import org.onap.policy.common.logging.flexlogger.FlexLogger; 
import org.onap.policy.common.logging.flexlogger.Logger; 

public class ActionPolicy extends Policy {
	
	/**
	 * ActionPolicy Fields
	 */
	private static final Logger LOGGER = FlexLogger.getLogger(ActionPolicy.class);
	
	public static final String JSON_CONFIG = "JSON";
	
	public static final String PDP_ACTION = "PDP";
	public static final String PEP_ACTION = "PEP";
	public static final String TYPE_ACTION = "REST";

	public static final String GET_METHOD = "GET";
	public static final String PUT_METHOD = "PUT";
	public static final String POST_METHOD = "POST";

	public static final String PERFORMER_ATTRIBUTEID = "performer";
	public static final String TYPE_ATTRIBUTEID = "type";
	public static final String METHOD_ATTRIBUTEID = "method";
	public static final String HEADERS_ATTRIBUTEID = "headers";
	public static final String URL_ATTRIBUTEID = "url";
	public static final String BODY_ATTRIBUTEID = "body";
	
	private static boolean isAttribute = false;

	
	List<String> dynamicLabelRuleAlgorithms = new LinkedList<>();
	List<String> dynamicFieldFunctionRuleAlgorithms = new LinkedList<>();
	List<String> dynamicFieldOneRuleAlgorithms = new LinkedList<>();
	List<String> dynamicFieldTwoRuleAlgorithms = new LinkedList<>();
	
	protected Map<String, String> dropDownMap = new HashMap<>();
	
	
	public ActionPolicy() {
		super();
	}
	
	public ActionPolicy(PolicyRestAdapter policyAdapter){
		this.policyAdapter = policyAdapter;
	}
	
	@Override
	public Map<String, String> savePolicies() throws Exception {
		
		Map<String, String> successMap = new HashMap<>();
		if(isPolicyExists()){
			successMap.put("EXISTS", "This Policy already exist on the PAP");
			return successMap;
		}
		
		if(!ActionPolicy.isAttribute) {
			successMap.put("invalidAttribute", "Action Attrbute was not in the database.");
			return successMap;
		}
		
		if(!isPreparedToSave()){
			//Prep and configure the policy for saving
			prepareToSave();
		}

		// Until here we prepared the data and here calling the method to create xml.
		Path newPolicyPath = null;
		newPolicyPath = Paths.get(policyAdapter.getNewFileName());
		successMap = createPolicy(newPolicyPath,getCorrectPolicyDataObject() );		
		return successMap;		
	}
	
	//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
	@Override
	public boolean prepareToSave() throws Exception{

		if(isPreparedToSave()){
			//we have already done this
			return true;
		}
		
		int version = 0;
		String policyID = policyAdapter.getPolicyID();
		version = policyAdapter.getHighestVersion();
		
		// Create the Instance for pojo, PolicyType object is used in marshalling.
		if (policyAdapter.getPolicyType().equals("Action")) {
			PolicyType policyConfig = new PolicyType();

			policyConfig.setVersion(Integer.toString(version));
			policyConfig.setPolicyId(policyID);
			policyConfig.setTarget(new TargetType());
			policyAdapter.setData(policyConfig);
		}
		
		policyName = policyAdapter.getNewFileName();
		
		if (policyAdapter.getData() != null) {
			// Action body is optional so checking value provided or not
			String comboDictValue = policyAdapter.getActionAttribute();
	        String actionBody = getActionPolicyDict(comboDictValue).getBody();
			if(!(actionBody==null || "".equals(actionBody))){	
				saveActionBody(policyName, actionBody);
			} else {
				if(!isAttribute){
					LOGGER.error(XACMLErrorConstants.ERROR_DATA_ISSUE + "Could not find " + comboDictValue + " in the ActionPolicyDict table.");
					return false;
				}
			}
			
			PolicyType actionPolicy = (PolicyType) policyAdapter.getData();
			actionPolicy.setDescription(policyAdapter.getPolicyDescription());
			actionPolicy.setRuleCombiningAlgId(policyAdapter.getRuleCombiningAlgId());

			AllOfType allOf = new AllOfType();
			
			Map<String, String> dynamicFieldComponentAttributes = policyAdapter.getDynamicFieldConfigAttributes();
			
			// If there is any dynamic field attributes create the matches here
			for (String keyField : dynamicFieldComponentAttributes.keySet()) {
				String key = keyField;
				String value = dynamicFieldComponentAttributes.get(key);
				MatchType dynamicMatch = createDynamicMatch(key, value);
				allOf.getMatch().add(dynamicMatch);
			}

			AnyOfType anyOf = new AnyOfType();
			anyOf.getAllOf().add(allOf);

			TargetType target = new TargetType();
			target.getAnyOf().add(anyOf);
			
			// Adding the target to the policy element
			actionPolicy.setTarget(target);
			
			RuleType rule = new RuleType();
			rule.setRuleId(policyAdapter.getRuleID());

			rule.setEffect(EffectType.PERMIT);
			rule.setTarget(new TargetType());
			
			dynamicLabelRuleAlgorithms = policyAdapter.getDynamicRuleAlgorithmLabels();
			dynamicFieldFunctionRuleAlgorithms = policyAdapter.getDynamicRuleAlgorithmCombo();
			dynamicFieldOneRuleAlgorithms = policyAdapter.getDynamicRuleAlgorithmField1();
			dynamicFieldTwoRuleAlgorithms = policyAdapter.getDynamicRuleAlgorithmField2();
			//dropDownMap = policyAdapter.getDropDownMap();
			dropDownMap = createDropDownMap();
						
			// Rule attributes are optional and dynamic so check and add them to condition.
			if (dynamicLabelRuleAlgorithms != null && dynamicLabelRuleAlgorithms.size() > 0) {
				boolean isCompound = false;
				ConditionType condition = new ConditionType();
				int index = dynamicFieldOneRuleAlgorithms.size() - 1;

				for (String labelAttr : dynamicLabelRuleAlgorithms) {
					// if the rule algorithm as a label means it is a compound
					if (dynamicFieldOneRuleAlgorithms.get(index).toString().equals(labelAttr)) {
						ApplyType actionApply = new ApplyType();

						String selectedFunction = (String) dynamicFieldFunctionRuleAlgorithms.get(index).toString();
						String value1 = (String) dynamicFieldOneRuleAlgorithms.get(index).toString();
						String value2 = dynamicFieldTwoRuleAlgorithms.get(index).toString();
						actionApply.setFunctionId(dropDownMap.get(selectedFunction));
						actionApply.getExpression().add(new ObjectFactory().createApply(getInnerActionApply(value1)));
						actionApply.getExpression().add(new ObjectFactory().createApply(getInnerActionApply(value2)));
						condition.setExpression(new ObjectFactory().createApply(actionApply));
						isCompound = true;
					}
				}
				// if rule algorithm not a compound
				if (!isCompound) {
					condition.setExpression(new ObjectFactory().createApply(getInnerActionApply(dynamicLabelRuleAlgorithms.get(index).toString())));
				}
				rule.setCondition(condition);
			}
			// set the obligations to rule
			rule.setObligationExpressions(getObligationExpressions());
			actionPolicy.getCombinerParametersOrRuleCombinerParametersOrVariableDefinition().add(rule);
			policyAdapter.setPolicyData(actionPolicy);
		}  else {
			PolicyLogger.error(MessageCodes.ERROR_DATA_ISSUE + "Unsupported data object." + policyAdapter.getData().getClass().getCanonicalName());
		}	

		setPreparedToSave(true);
		return true;
	}
	
	// Saving the json Configurations file if exists at server location for action policy.
	private void saveActionBody(String policyName, String actionBodyData) {
		try {
			if(policyName.endsWith(".xml")){
				policyName = policyName.replace(".xml", "");
			}
			File file = new File(ACTION_HOME+ File.separator + policyName + ".json");
			FileWriter fw = new FileWriter(file.getAbsoluteFile());
			BufferedWriter bw = new BufferedWriter(fw);
			bw.write(actionBodyData);
			bw.close();
			if (LOGGER.isInfoEnabled()) {
				LOGGER.info("Action Body is succesfully saved at " + file.getAbsolutePath());
			}
		} catch (IOException e) {
			LOGGER.error("Exception Occured"+e);
		}
	}
	
	// Data required for obligation part is setting here.
	private ObligationExpressionsType getObligationExpressions() {
		ObligationExpressionsType obligations = new ObligationExpressionsType();

		ObligationExpressionType obligation = new ObligationExpressionType();
        String comboDictValue = policyAdapter.getActionAttribute();
		obligation.setObligationId(comboDictValue);
		obligation.setFulfillOn(EffectType.PERMIT);

		// Add Action Assignment:
		AttributeAssignmentExpressionType assignment1 = new AttributeAssignmentExpressionType();
		assignment1.setAttributeId(PERFORMER_ATTRIBUTEID);
		assignment1.setCategory(CATEGORY_RECIPIENT_SUBJECT);

		AttributeValueType actionNameAttributeValue = new AttributeValueType();
		actionNameAttributeValue.setDataType(STRING_DATATYPE);
		actionNameAttributeValue.getContent().add(performer.get(policyAdapter.getActionPerformer()));

		assignment1.setExpression(new ObjectFactory().createAttributeValue(actionNameAttributeValue));
		obligation.getAttributeAssignmentExpression().add(assignment1);

		// Add Type Assignment:
		AttributeAssignmentExpressionType assignmentType = new AttributeAssignmentExpressionType();
		assignmentType.setAttributeId(TYPE_ATTRIBUTEID);
		assignmentType.setCategory(CATEGORY_RESOURCE);

		AttributeValueType typeAttributeValue = new AttributeValueType();
		typeAttributeValue.setDataType(STRING_DATATYPE);
		String actionDictType = getActionPolicyDict(comboDictValue).getType();
		typeAttributeValue.getContent().add(actionDictType);

		assignmentType.setExpression(new ObjectFactory().createAttributeValue(typeAttributeValue));
		obligation.getAttributeAssignmentExpression().add(assignmentType);

		// Add Rest_URL Assignment:
		AttributeAssignmentExpressionType assignmentURL = new AttributeAssignmentExpressionType();
		assignmentURL.setAttributeId(URL_ATTRIBUTEID);
		assignmentURL.setCategory(CATEGORY_RESOURCE);

		AttributeValueType actionURLAttributeValue = new AttributeValueType();
		actionURLAttributeValue.setDataType(URI_DATATYPE);
		String actionDictUrl = getActionPolicyDict(comboDictValue).getUrl();
		actionURLAttributeValue.getContent().add(actionDictUrl);

		assignmentURL.setExpression(new ObjectFactory().createAttributeValue(actionURLAttributeValue));
		obligation.getAttributeAssignmentExpression().add(assignmentURL);

		// Add Method Assignment:
		AttributeAssignmentExpressionType assignmentMethod = new AttributeAssignmentExpressionType();
		assignmentMethod.setAttributeId(METHOD_ATTRIBUTEID);
		assignmentMethod.setCategory(CATEGORY_RESOURCE);

		AttributeValueType methodAttributeValue = new AttributeValueType();
		methodAttributeValue.setDataType(STRING_DATATYPE);
		String actionDictMethod = getActionPolicyDict(comboDictValue).getMethod();
		methodAttributeValue.getContent().add(actionDictMethod);

		assignmentMethod.setExpression(new ObjectFactory().createAttributeValue(methodAttributeValue));
		obligation.getAttributeAssignmentExpression().add(assignmentMethod);

		// Add JSON_URL Assignment:
		String actionBody = getActionPolicyDict(comboDictValue).getBody();
		if (actionBody != null) {
			AttributeAssignmentExpressionType assignmentJsonURL = new AttributeAssignmentExpressionType();
			assignmentJsonURL.setAttributeId(BODY_ATTRIBUTEID);
			assignmentJsonURL.setCategory(CATEGORY_RESOURCE);

			AttributeValueType jsonURLAttributeValue = new AttributeValueType();
			jsonURLAttributeValue.setDataType(URI_DATATYPE);
			jsonURLAttributeValue.getContent().add(CONFIG_URL + "/Action/"  + policyName + ".json");

			assignmentJsonURL.setExpression(new ObjectFactory().createAttributeValue(jsonURLAttributeValue));
			obligation.getAttributeAssignmentExpression().add(assignmentJsonURL);
		}

		if(getActionPolicyDict(comboDictValue).getHeader() != null){
			String headerVal = getActionPolicyDict(comboDictValue).getHeader();
			if(headerVal != null && !headerVal.equals("")){
				// parse it on : to get number of headers
				String[] result = headerVal.split(":");
				for (String eachString : result){
					// parse each value on =
					String[] textFieldVals = eachString.split("=");
					obligation.getAttributeAssignmentExpression().add(addDynamicHeaders(textFieldVals[0], textFieldVals[1]));
				}
			}

		}
			
		obligations.getObligationExpression().add(obligation);
		return obligations;
	}

	
	// if compound setting the inner apply here
	protected ApplyType getInnerActionApply(String value1Label) {
		ApplyType actionApply = new ApplyType();
		int index = 0;
		// check the index for the label.
		for (String labelAttr : dynamicLabelRuleAlgorithms) {
			if (labelAttr.equals(value1Label)) {
				String value1 = dynamicFieldOneRuleAlgorithms.get(index).toString();
				// check if the row contains label again
				for (String labelValue : dynamicLabelRuleAlgorithms) {
					if (labelValue.equals(value1)) {
						return getCompoundApply(index);
					}
				}

				// Getting the values from the form.
				String functionKey = dynamicFieldFunctionRuleAlgorithms.get(index).toString();
				String value2 = dynamicFieldTwoRuleAlgorithms.get(index).toString();
				actionApply.setFunctionId(dropDownMap.get(functionKey));
				// if two text field are rule attributes.
				if ((value1.contains(RULE_VARIABLE)) && (value2.contains(RULE_VARIABLE))) {
					ApplyType innerActionApply1 = new ApplyType();
					ApplyType innerActionApply2 = new ApplyType();
					AttributeDesignatorType attributeDesignator1 = new AttributeDesignatorType();
					AttributeDesignatorType attributeDesignator2 = new AttributeDesignatorType();
					// If selected function is Integer function set integer functionID
					if (functionKey.toLowerCase().contains("integer")) {
						innerActionApply1.setFunctionId(FUNTION_INTEGER_ONE_AND_ONLY);
						innerActionApply2.setFunctionId(FUNTION_INTEGER_ONE_AND_ONLY);
						attributeDesignator1.setDataType(INTEGER_DATATYPE);
						attributeDesignator2.setDataType(INTEGER_DATATYPE);
					} else {
						// If selected function is not a Integer function
						// set String functionID
						innerActionApply1.setFunctionId(FUNCTION_STRING_ONE_AND_ONLY);
						innerActionApply2.setFunctionId(FUNCTION_STRING_ONE_AND_ONLY);
						attributeDesignator1.setDataType(STRING_DATATYPE);
						attributeDesignator2.setDataType(STRING_DATATYPE);
					}
					attributeDesignator1.setCategory(CATEGORY_RESOURCE);
					attributeDesignator2.setCategory(CATEGORY_RESOURCE);

					// Here set actual field values
					attributeDesignator1.setAttributeId(value1.contains("resource:") ? value1.substring(9): value1.substring(8));
					attributeDesignator2.setAttributeId(value1.contains("resource:") ? value1.substring(9): value1.substring(8));

					innerActionApply1.getExpression().add(new ObjectFactory().createAttributeDesignator(attributeDesignator1));
					innerActionApply2.getExpression().add(new ObjectFactory().createAttributeDesignator(attributeDesignator2));

					actionApply.getExpression().add(new ObjectFactory().createApply(innerActionApply1));
					actionApply.getExpression().add(new ObjectFactory().createApply(innerActionApply2));

				} else {// if either of one text field is rule attribute.
					ApplyType innerActionApply = new ApplyType();
					AttributeDesignatorType attributeDesignator = new AttributeDesignatorType();
					AttributeValueType actionConditionAttributeValue = new AttributeValueType();

					if (functionKey.toLowerCase().contains("integer")) {
						innerActionApply.setFunctionId(FUNTION_INTEGER_ONE_AND_ONLY);
						actionConditionAttributeValue.setDataType(INTEGER_DATATYPE);
						attributeDesignator.setDataType(INTEGER_DATATYPE);
					} else {
						innerActionApply.setFunctionId(FUNCTION_STRING_ONE_AND_ONLY);
						actionConditionAttributeValue.setDataType(STRING_DATATYPE);
						attributeDesignator.setDataType(STRING_DATATYPE);
					}

					String attributeId = null;
					String attributeValue = null;

					// Find which textField has rule attribute and set it as
					attributeId = value1;
					attributeValue = value2;

					if (attributeId != null) {
						attributeDesignator.setCategory(CATEGORY_RESOURCE);
						attributeDesignator.setAttributeId(attributeId);
					}
					actionConditionAttributeValue.getContent().add(attributeValue);
					innerActionApply.getExpression().add(new ObjectFactory().createAttributeDesignator(attributeDesignator));
					// Decide the order of element based the values.
					if (attributeId.equals(value1)) {
						actionApply.getExpression().add(new ObjectFactory().createApply(innerActionApply));
						actionApply.getExpression().add(new ObjectFactory().createAttributeValue(actionConditionAttributeValue));
					} else {
						actionApply.getExpression().add(new ObjectFactory().createAttributeValue(actionConditionAttributeValue));
						actionApply.getExpression().add(new ObjectFactory().createApply(innerActionApply));
					}
				}
			}
			index++;
		}
		return actionApply;
	}

	// if the rule algorithm is multiple compound one setting the apply
	protected ApplyType getCompoundApply(int index) {
		ApplyType actionApply = new ApplyType();
		String selectedFunction = dynamicFieldFunctionRuleAlgorithms.get(index).toString();
		String value1 = dynamicFieldOneRuleAlgorithms.get(index).toString();
		String value2 = dynamicFieldTwoRuleAlgorithms.get(index).toString();
		actionApply.setFunctionId(dropDownMap.get(selectedFunction));
		actionApply.getExpression().add(new ObjectFactory().createApply(getInnerActionApply(value1)));
		actionApply.getExpression().add(new ObjectFactory().createApply(getInnerActionApply(value2)));
		return actionApply;
	}
		
	// Adding the dynamic headers if any
	private AttributeAssignmentExpressionType addDynamicHeaders(String header, String value) {
		AttributeAssignmentExpressionType assignmentHeaders = new AttributeAssignmentExpressionType();
		assignmentHeaders.setAttributeId("headers:" + header);
		assignmentHeaders.setCategory(CATEGORY_RESOURCE);

		AttributeValueType headersAttributeValue = new AttributeValueType();
		headersAttributeValue.setDataType(STRING_DATATYPE);
		headersAttributeValue.getContent().add(value);

		assignmentHeaders.setExpression(new ObjectFactory().createAttributeValue(headersAttributeValue));
		return assignmentHeaders;
	}
	
	private Map<String,String> createDropDownMap(){
		JPAUtils jpaUtils = null;
		Map<String, String> dropDownMap = new HashMap<>();
		try {
			jpaUtils = JPAUtils.getJPAUtilsInstance(XACMLPapServlet.getEmf());
		} catch (Exception e) {
			LOGGER.error("Exception Occured"+e);
		}
		if(jpaUtils != null){
			Map<Datatype, List<FunctionDefinition>> functionMap = jpaUtils.getFunctionDatatypeMap();
			
			for (Datatype id : functionMap.keySet()) {
				List<FunctionDefinition> functionDefinitions = (List<FunctionDefinition>) functionMap
						.get(id);
				for (FunctionDefinition functionDef : functionDefinitions) {
					dropDownMap.put(functionDef.getShortname(),functionDef.getXacmlid());
				}
			}
		}
		return dropDownMap;
	}
	
	private ActionPolicyDict getActionPolicyDict(String attributeName){
		ActionPolicyDict retObj = new ActionPolicyDict();
		EntityManager em = XACMLPapServlet.getEmf().createEntityManager();
		Query getActionPolicyDicts = em.createNamedQuery("ActionPolicyDict.findAll");	
		List<?> actionPolicyDicts = getActionPolicyDicts.getResultList(); 	
		
		for (Object id : actionPolicyDicts) {
			ActionPolicyDict actionPolicy = (ActionPolicyDict) id;
			if(attributeName.equals(actionPolicy.getAttributeName())){
				isAttribute = true;
				retObj = actionPolicy;
				break;
			}
		}
		em.close();
		return retObj;
	}

	@Override
	public Object getCorrectPolicyDataObject() {
		return policyAdapter.getPolicyData();
	}

}