/*-
 * ============LICENSE_START=======================================================
 * ONAP-PAP-REST
 * ================================================================================
 * Copyright (C) 2017, 2019 AT&T Intellectual Property. All rights reserved.
 * Modified Copyright (C) 2018 Samsung Electronics Co., Ltd.
 * Modified Copyright (C) 2019 Bell Canada.
 * ================================================================================
 * 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 com.att.research.xacml.api.pap.PAPException;
import com.att.research.xacml.std.IdentifierImpl;

import java.io.BufferedWriter;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.net.URI;
import java.net.URISyntaxException;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.HashMap;
import java.util.Map;

import oasis.names.tc.xacml._3_0.core.schema.wd_17.AdviceExpressionType;
import oasis.names.tc.xacml._3_0.core.schema.wd_17.AdviceExpressionsType;
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.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.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.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.apache.commons.io.FilenameUtils;
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;
import org.onap.policy.rest.adapter.PolicyRestAdapter;
import org.onap.policy.utils.PolicyUtils;

public class ConfigPolicy extends Policy {

    /**
     * Config Fields
     */
    private static final Logger LOGGER = FlexLogger.getLogger(ConfigPolicy.class);

    public static final String JSON_CONFIG = "JSON";
    public static final String XML_CONFIG = "XML";
    public static final String PROPERTIES_CONFIG = "PROPERTIES";
    public static final String OTHER_CONFIG = "OTHER";

    private String configBodyData;

    public ConfigPolicy() {
        super();
    }

    public ConfigPolicy(PolicyRestAdapter policyAdapter) {
        this.policyAdapter = policyAdapter;
    }

    // Saving the Configurations file at server location for config policy.
    protected void saveConfigurations(String policyName) {
        String fileName = getConfigFile(policyName);
        try (BufferedWriter bw = new BufferedWriter(new FileWriter(CONFIG_HOME + File.separator + fileName))) {
            bw.write(configBodyData);
            if (LOGGER.isDebugEnabled()) {
                LOGGER.debug("Configuration is succesfully saved");
            }
        } catch (IOException e) {
            LOGGER.error("Exception Occured while writing Configuration Data" + e);
        }
    }

    // Here we are adding the extension for the configurations file based on the
    // config type selection for saving.
    private String getConfigFile(String filename) {
        filename = removeExtentsion(filename);
        String id = policyAdapter.getConfigType();

        if (id == null) {
            return filename;
        }
        switch (id.toUpperCase()) {
            case JSON_CONFIG:
                return filename + ".json";
            case XML_CONFIG:
                return filename + ".xml";
            case PROPERTIES_CONFIG:
                return filename + ".properties";
            case OTHER_CONFIG:
                return filename + ".txt";
            default:
                return filename;

        }
    }

    private String removeExtentsion(String filename) {
        filename = FilenameUtils.removeExtension(filename);
        if (filename.endsWith(".xml")) {
            filename = filename.substring(0, filename.length() - 4);
        }
        return filename;
    }

    // Validations for Config form
    /*
     * FORM VALIDATION WILL BE DONE BY THE PAP-ADMIN before creating JSON object...
     * BODY VALIDATION WILL BE DONE BY THE PAP-REST after receiving and deserializing the JSON object
     */
    public boolean validateConfigForm() {

        isValidForm = true;

        /*
         * Validate Text Area Body
         */
        configBodyData = policyAdapter.getConfigBodyData();
        String id = policyAdapter.getConfigType();
        if (id == null) {
            return isValidForm;
        }
        switch (id) {
            case JSON_CONFIG:
                if (!PolicyUtils.isJSONValid(configBodyData)) {
                    isValidForm = false;
                }
                break;
            case XML_CONFIG:
                if (!PolicyUtils.isXMLValid(configBodyData)) {
                    isValidForm = false;
                }
                break;
            case PROPERTIES_CONFIG:
                if (!PolicyUtils.isPropValid(configBodyData) || configBodyData.equals("")) {
                    isValidForm = false;
                }
                break;
            case OTHER_CONFIG:
                if (configBodyData.equals("")) {
                    isValidForm = false;
                }
                break;
        }
        return isValidForm;

    }

    @Override
    public Map<String, String> savePolicies() throws PAPException {

        Map<String, String> successMap = new HashMap<>();
        if (isPolicyExists()) {
            successMap.put("EXISTS", "This Policy already exist on the PAP");
            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 PAPException {

        if (isPreparedToSave()) {
            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("Config")) {
            PolicyType policyConfig = new PolicyType();

            policyConfig.setVersion(Integer.toString(version));
            policyConfig.setPolicyId(policyID);
            policyConfig.setTarget(new TargetType());
            policyAdapter.setData(policyConfig);
        }

        policyName = policyAdapter.getNewFileName();
        configBodyData = policyAdapter.getConfigBodyData();
        saveConfigurations(policyName);

        if (policyAdapter.getData() != null) {
            PolicyType configPolicy = (PolicyType) policyAdapter.getData();

            configPolicy.setDescription(policyAdapter.getPolicyDescription());

            configPolicy.setRuleCombiningAlgId(policyAdapter.getRuleCombiningAlgId());
            AllOfType allOfOne = new AllOfType();

            String fileName = policyAdapter.getNewFileName();
            String name = fileName.substring(fileName.lastIndexOf("\\") + 1);
            if ((name == null) || (name.equals(""))) {
                name = fileName.substring(fileName.lastIndexOf("/") + 1);
            }
            allOfOne.getMatch().add(createMatch("PolicyName", name));
            AllOfType allOf = new AllOfType();

            // Adding the matches to AllOfType element Match for Onap
            allOf.getMatch().add(createMatch("ONAPName", policyAdapter.getOnapName()));
            // Match for riskType
            allOf.getMatch().add(createDynamicMatch("RiskType", policyAdapter.getRiskType()));
            // Match for riskLevel
            allOf.getMatch().add(createDynamicMatch("RiskLevel", String.valueOf(policyAdapter.getRiskLevel())));
            // Match for riskguard
            allOf.getMatch().add(createDynamicMatch("guard", policyAdapter.getGuard()));
            // Match for ttlDate
            allOf.getMatch().add(createDynamicMatch("TTLDate", policyAdapter.getTtlDate()));
            // Match for ConfigName
            allOf.getMatch().add(createMatch("ConfigName", policyAdapter.getConfigName()));

            Map<String, String> dynamicFieldConfigAttributes = policyAdapter.getDynamicFieldConfigAttributes();

            // If there is any dynamic field create the matches here
            for (String keyField : dynamicFieldConfigAttributes.keySet()) {
                String key = keyField;
                String value = dynamicFieldConfigAttributes.get(key);
                MatchType dynamicMatch = createDynamicMatch(key, value);
                allOf.getMatch().add(dynamicMatch);
            }

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

            TargetType target = new TargetType();
            ((TargetType) target).getAnyOf().add(anyOf);

            // Adding the target to the policy element
            configPolicy.setTarget((TargetType) target);

            RuleType rule = new RuleType();
            rule.setRuleId(policyAdapter.getRuleID());
            rule.setEffect(EffectType.PERMIT);

            // Create Target in Rule
            AllOfType allOfInRule = new AllOfType();

            // Creating match for ACCESS in rule target
            MatchType accessMatch = new MatchType();
            AttributeValueType accessAttributeValue = new AttributeValueType();
            accessAttributeValue.setDataType(STRING_DATATYPE);
            accessAttributeValue.getContent().add("ACCESS");
            accessMatch.setAttributeValue(accessAttributeValue);
            AttributeDesignatorType accessAttributeDesignator = new AttributeDesignatorType();
            URI accessURI = null;
            try {
                accessURI = new URI(ACTION_ID);
            } catch (URISyntaxException e) {
                PolicyLogger.error(MessageCodes.ERROR_DATA_ISSUE, e, "ConfigPolicy", "Exception creating ACCESS URI");
            }
            accessAttributeDesignator.setCategory(CATEGORY_ACTION);
            accessAttributeDesignator.setDataType(STRING_DATATYPE);
            accessAttributeDesignator.setAttributeId(new IdentifierImpl(accessURI).stringValue());
            accessMatch.setAttributeDesignator(accessAttributeDesignator);
            accessMatch.setMatchId(FUNCTION_STRING_EQUAL_IGNORE);

            // Creating Config Match in rule Target
            MatchType configMatch = new MatchType();
            AttributeValueType configAttributeValue = new AttributeValueType();
            configAttributeValue.setDataType(STRING_DATATYPE);
            configAttributeValue.getContent().add("Config");
            configMatch.setAttributeValue(configAttributeValue);
            AttributeDesignatorType configAttributeDesignator = new AttributeDesignatorType();
            URI configURI = null;
            try {
                configURI = new URI(RESOURCE_ID);
            } catch (URISyntaxException e) {
                PolicyLogger.error(MessageCodes.ERROR_DATA_ISSUE, e, "ConfigPolicy", "Exception creating Config URI");
            }
            configAttributeDesignator.setCategory(CATEGORY_RESOURCE);
            configAttributeDesignator.setDataType(STRING_DATATYPE);
            configAttributeDesignator.setAttributeId(new IdentifierImpl(configURI).stringValue());
            configMatch.setAttributeDesignator(configAttributeDesignator);
            configMatch.setMatchId(FUNCTION_STRING_EQUAL_IGNORE);

            allOfInRule.getMatch().add(accessMatch);
            allOfInRule.getMatch().add(configMatch);

            AnyOfType anyOfInRule = new AnyOfType();
            anyOfInRule.getAllOf().add(allOfInRule);

            TargetType targetInRule = new TargetType();
            targetInRule.getAnyOf().add(anyOfInRule);

            rule.setTarget(targetInRule);
            rule.setAdviceExpressions(getAdviceExpressions(version, policyName));

            configPolicy.getCombinerParametersOrRuleCombinerParametersOrVariableDefinition().add(rule);
            policyAdapter.setPolicyData(configPolicy);

        } else {
            PolicyLogger.error("Unsupported data object." + policyAdapter.getData().getClass().getCanonicalName());
        }
        setPreparedToSave(true);
        return true;
    }

    // Data required for Advice part is setting here.
    private AdviceExpressionsType getAdviceExpressions(int version, String fileName) {
        AdviceExpressionsType advices = new AdviceExpressionsType();
        AdviceExpressionType advice = new AdviceExpressionType();
        advice.setAdviceId("configID");
        advice.setAppliesTo(EffectType.PERMIT);

        // For Configuration
        AttributeAssignmentExpressionType assignment1 = new AttributeAssignmentExpressionType();
        assignment1.setAttributeId("type");
        assignment1.setCategory(CATEGORY_RESOURCE);
        assignment1.setIssuer("");

        AttributeValueType configNameAttributeValue = new AttributeValueType();
        configNameAttributeValue.setDataType(STRING_DATATYPE);
        configNameAttributeValue.getContent().add("Configuration");
        assignment1.setExpression(new ObjectFactory().createAttributeValue(configNameAttributeValue));

        advice.getAttributeAssignmentExpression().add(assignment1);

        // For Config file Url if configurations are provided.
        if (policyAdapter.getConfigType() != null) {
            AttributeAssignmentExpressionType assignment2 = new AttributeAssignmentExpressionType();
            assignment2.setAttributeId("URLID");
            assignment2.setCategory(CATEGORY_RESOURCE);
            assignment2.setIssuer("");

            AttributeValueType AttributeValue = new AttributeValueType();
            AttributeValue.setDataType(URI_DATATYPE);
            String content = "$URL" + "/Config/" + getConfigFile(policyName);
            AttributeValue.getContent().add(content);
            assignment2.setExpression(new ObjectFactory().createAttributeValue(AttributeValue));

            advice.getAttributeAssignmentExpression().add(assignment2);
            AttributeAssignmentExpressionType assignment3 = new AttributeAssignmentExpressionType();
            assignment3.setAttributeId("PolicyName");
            assignment3.setCategory(CATEGORY_RESOURCE);
            assignment3.setIssuer("");

            AttributeValueType attributeValue3 = new AttributeValueType();
            attributeValue3.setDataType(STRING_DATATYPE);

            fileName = FilenameUtils.removeExtension(fileName);
            fileName = fileName + ".xml";
            String name = fileName.substring(fileName.lastIndexOf("\\") + 1);
            if ((name == null) || (name.equals(""))) {
                name = fileName.substring(fileName.lastIndexOf("/") + 1);
            }
            attributeValue3.getContent().add(name);
            assignment3.setExpression(new ObjectFactory().createAttributeValue(attributeValue3));
            advice.getAttributeAssignmentExpression().add(assignment3);

            AttributeAssignmentExpressionType assignment4 = new AttributeAssignmentExpressionType();
            assignment4.setAttributeId("VersionNumber");
            assignment4.setCategory(CATEGORY_RESOURCE);
            assignment4.setIssuer("");

            AttributeValueType configNameAttributeValue4 = new AttributeValueType();
            configNameAttributeValue4.setDataType(STRING_DATATYPE);
            configNameAttributeValue4.getContent().add(Integer.toString(version));
            assignment4.setExpression(new ObjectFactory().createAttributeValue(configNameAttributeValue4));

            advice.getAttributeAssignmentExpression().add(assignment4);

            AttributeAssignmentExpressionType assignment5 = new AttributeAssignmentExpressionType();
            assignment5.setAttributeId("matching:" + ONAPID);
            assignment5.setCategory(CATEGORY_RESOURCE);
            assignment5.setIssuer("");

            AttributeValueType configNameAttributeValue5 = new AttributeValueType();
            configNameAttributeValue5.setDataType(STRING_DATATYPE);
            configNameAttributeValue5.getContent().add(policyAdapter.getOnapName());
            assignment5.setExpression(new ObjectFactory().createAttributeValue(configNameAttributeValue5));

            advice.getAttributeAssignmentExpression().add(assignment5);

            AttributeAssignmentExpressionType assignment6 = new AttributeAssignmentExpressionType();
            assignment6.setAttributeId("matching:" + CONFIGID);
            assignment6.setCategory(CATEGORY_RESOURCE);
            assignment6.setIssuer("");

            AttributeValueType configNameAttributeValue6 = new AttributeValueType();
            configNameAttributeValue6.setDataType(STRING_DATATYPE);
            configNameAttributeValue6.getContent().add(policyAdapter.getConfigName());
            assignment6.setExpression(new ObjectFactory().createAttributeValue(configNameAttributeValue6));

            advice.getAttributeAssignmentExpression().add(assignment6);

            Map<String, String> dynamicFieldConfigAttributes = policyAdapter.getDynamicFieldConfigAttributes();
            for (String keyField : dynamicFieldConfigAttributes.keySet()) {
                String key = keyField;
                String value = dynamicFieldConfigAttributes.get(key);
                AttributeAssignmentExpressionType assignment7 = new AttributeAssignmentExpressionType();
                assignment7.setAttributeId("matching:" + key);
                assignment7.setCategory(CATEGORY_RESOURCE);
                assignment7.setIssuer("");

                AttributeValueType configNameAttributeValue7 = new AttributeValueType();
                configNameAttributeValue7.setDataType(STRING_DATATYPE);
                configNameAttributeValue7.getContent().add(value);
                assignment7.setExpression(new ObjectFactory().createAttributeValue(configNameAttributeValue7));

                advice.getAttributeAssignmentExpression().add(assignment7);
            }
        }

        // Risk Attributes
        AttributeAssignmentExpressionType assignment8 = new AttributeAssignmentExpressionType();
        assignment8.setAttributeId("RiskType");
        assignment8.setCategory(CATEGORY_RESOURCE);
        assignment8.setIssuer("");

        AttributeValueType configNameAttributeValue8 = new AttributeValueType();
        configNameAttributeValue8.setDataType(STRING_DATATYPE);
        configNameAttributeValue8.getContent().add(policyAdapter.getRiskType());
        assignment8.setExpression(new ObjectFactory().createAttributeValue(configNameAttributeValue8));

        advice.getAttributeAssignmentExpression().add(assignment8);

        AttributeAssignmentExpressionType assignment9 = new AttributeAssignmentExpressionType();
        assignment9.setAttributeId("RiskLevel");
        assignment9.setCategory(CATEGORY_RESOURCE);
        assignment9.setIssuer("");

        AttributeValueType configNameAttributeValue9 = new AttributeValueType();
        configNameAttributeValue9.setDataType(STRING_DATATYPE);
        configNameAttributeValue9.getContent().add(policyAdapter.getRiskLevel());
        assignment9.setExpression(new ObjectFactory().createAttributeValue(configNameAttributeValue9));

        advice.getAttributeAssignmentExpression().add(assignment9);

        AttributeAssignmentExpressionType assignment10 = new AttributeAssignmentExpressionType();
        assignment10.setAttributeId("guard");
        assignment10.setCategory(CATEGORY_RESOURCE);
        assignment10.setIssuer("");

        AttributeValueType configNameAttributeValue10 = new AttributeValueType();
        configNameAttributeValue10.setDataType(STRING_DATATYPE);
        configNameAttributeValue10.getContent().add(policyAdapter.getGuard());
        assignment10.setExpression(new ObjectFactory().createAttributeValue(configNameAttributeValue10));

        advice.getAttributeAssignmentExpression().add(assignment10);

        AttributeAssignmentExpressionType assignment11 = new AttributeAssignmentExpressionType();
        assignment11.setAttributeId("TTLDate");
        assignment11.setCategory(CATEGORY_RESOURCE);
        assignment11.setIssuer("");

        AttributeValueType configNameAttributeValue11 = new AttributeValueType();
        configNameAttributeValue11.setDataType(STRING_DATATYPE);
        configNameAttributeValue11.getContent().add(policyAdapter.getTtlDate());
        assignment11.setExpression(new ObjectFactory().createAttributeValue(configNameAttributeValue11));

        advice.getAttributeAssignmentExpression().add(assignment11);

        advices.getAdviceExpression().add(advice);
        return advices;
    }

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

}