/*-
 * ============LICENSE_START=======================================================
 * ONAP-PAP-REST
 * ================================================================================
 * Copyright (C) 2017-2019 AT&T Intellectual Property. All rights reserved.
 * Modified Copyright (C) 2018 Samsung Electronics Co., Ltd.
 * ================================================================================
 * 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 com.att.research.xacml.util.XACMLProperties;
import com.att.research.xacmlatt.pdp.policy.PolicyDef;
import com.att.research.xacmlatt.pdp.policy.dom.DOMPolicyDef;

import java.io.IOException;
import java.io.InputStream;
import java.net.URI;
import java.net.URISyntaxException;
import java.nio.file.Files;
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.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.PolicySetType;
import oasis.names.tc.xacml._3_0.core.schema.wd_17.PolicyType;

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.XACMLRestProperties;
import org.onap.policy.rest.adapter.PolicyRestAdapter;
import org.onap.policy.xacml.util.XACMLPolicyWriter;

public abstract class Policy {

    private static final Logger LOGGER = FlexLogger.getLogger(Policy.class);

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

    public static final String ONAPID = "ONAPName";
    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;

    protected 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.onap.function.regex-match";
    public static final String FUNCTION_STRING_REGEXP_MATCH =
            "urn:oasis:names:tc:xacml:1.0:function:string-regexp-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 = "";

    protected static String CONFIG_HOME = null;
    protected static String ACTION_HOME = null;
    protected static String CONFIG_URL = null;

    protected Map<String, String> performer = new HashMap<>();

    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 PAPException;

    // 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 PAPException;

    // create match for onap 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.replaceAll("\\s+", ""));
        } catch (URISyntaxException e) {
            LOGGER.error("Exception Occured" + e);
        }
        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();
        String dataType = null;
        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.replaceAll("\\s+", ""));
        } catch (URISyntaxException e) {
            LOGGER.error("Exception Occured" + e);// 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;
    }

    // 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";
        }

        newFile = Paths.get(parent.toString(), fileName);
        if (newFile.toFile().exists()) {
            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.equals(EMPTY_STRING)) {
                policyDir = absolutePath.substring(absolutePath.lastIndexOf('/') + 1, absolutePath.length());
            }
        }

        String fileName = "default";
        if (!policyDir.equals(EMPTY_STRING)) {
            if ("ClosedLoop_PM".equals(policyConfigType)) {
                fileName = policyType + "_" + "PM" + "_" + java.lang.String.format(policyFileName) + "." + version
                        + ".xml";
            } else if ("ClosedLoop_Fault".equals(policyConfigType)) {
                fileName = policyType + "_" + "Fault" + "_" + java.lang.String.format(policyFileName) + "." + version
                        + ".xml";
            } else if ("Micro Service".equals(policyConfigType)) {
                fileName = policyType + "_" + "MS" + "_" + java.lang.String.format(policyFileName) + "." + version
                        + ".xml";
            } else if ("Optimization".equals(policyConfigType)) {
                fileName = policyType + "_" + "OOF" + "_" + java.lang.String.format(policyFileName) + "." + version
                        + ".xml";
            }
        }

        newFile = Paths.get(parentPath.toString(), fileName);

        if (newFile.toFile().exists()) {
            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<>();
        //
        // Is the root a PolicySet or Policy?
        //

        if (policyData instanceof PolicyType || policyData instanceof PolicySetType) {
            //
            // Write it out
            //
            // Does not need to be XACMLPolicyWriterWithPapNotify since it is
            // already in the PAP
            // and this transaction is intercepted up stream.
            try (InputStream inputStream = XACMLPolicyWriter.getXmlAsInputStream(policyData)) {
                PolicyDef policyDef = DOMPolicyDef.load(inputStream);
                if (policyDef == null) {
                    success.put("validation", "PolicyDef Validation Failed");
                } else {
                    success.put("success", "success");
                }
            } catch (Exception e) {
                LOGGER.error("PolicyDef Validation failed" + e);
                success.put("error", "Validation Failed");
            }
        } else {
            PolicyLogger.error("Unknown data type sent back.");
            return success;
        }
        return success;
    }

    public static String getConfigHome() {
        try {
            loadWebapps();
        } catch (Exception e) {
            LOGGER.debug(e);
            return null;
        }
        return configHome;
    }

    public static String getActionHome() {
        try {
            loadWebapps();
        } catch (Exception e) {
            LOGGER.debug(e);
            return null;
        }
        return actionHome;
    }

    private static void loadWebapps() throws PAPException {
        if (actionHome == null || configHome == null) {
            Path webappsPath = Paths.get(XACMLProperties.getProperty(XACMLRestProperties.PROP_PAP_WEBAPPS));
            // Sanity Check
            if (webappsPath == null) {
                PolicyLogger.error("Invalid Webapps Path Location property : " + XACMLRestProperties.PROP_PAP_WEBAPPS);
                throw new PAPException(
                        "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 (!webappsPathConfig.toFile().exists()) {
                try {
                    Files.createDirectories(webappsPathConfig);
                } catch (IOException e) {
                    PolicyLogger.error(MessageCodes.ERROR_PROCESS_FLOW, e, "Policy",
                            "Failed to create config directory");
                }
            }
            if (!webappsPathAction.toFile().exists()) {
                try {
                    Files.createDirectories(webappsPathAction);
                } catch (IOException e) {
                    PolicyLogger.error(MessageCodes.ERROR_PROCESS_FLOW, e, "Policy",
                            "Failed to create config directory");
                }
            }
            actionHome = webappsPathAction.toString();
            configHome = webappsPathConfig.toString();
        }
    }

    public boolean validateConfigForm() {
        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;
    }

}