/*-
 * ============LICENSE_START=======================================================
 * ONAP Policy Engine
 * ================================================================================
 * Copyright (C) 2017-2019 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.model;

import com.att.research.xacml.api.pap.PAPException;

import java.awt.Checkbox;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.LinkedList;
import java.util.List;
import java.util.Set;

import org.onap.policy.common.logging.flexlogger.FlexLogger;
import org.onap.policy.common.logging.flexlogger.Logger;
import org.onap.policy.rest.util.PolicyContainer;
import org.onap.policy.rest.util.PolicyItemSetChangeNotifier;
import org.onap.policy.xacml.api.XACMLErrorConstants;
import org.onap.policy.xacml.api.pap.OnapPDP;
import org.onap.policy.xacml.api.pap.OnapPDPGroup;
import org.onap.policy.xacml.api.pap.PAPPolicyEngine;

public class PDPGroupContainer extends PolicyItemSetChangeNotifier
        implements PolicyContainer.Indexed, PolicyContainer.ItemSetChangeNotifier {
    private static final long serialVersionUID = 1L;
    private static final Logger LOGGER = FlexLogger.getLogger(PDPGroupContainer.class);

    /**
     * String identifier of a file's "Id" property.
     */
    private static final String PROPERTY_ID = "Id";

    /**
     * String identifier of a file's "name" property.
     */
    private static final String PROPERTY_NAME = "Name";

    /**
     * String identifier of a file's "Description" property.
     */
    private static final String PROPERTY_DESCRIPTION = "Description";

    /**
     * String identifier of a file's "Default" property.
     */
    private static final String PROPERTY_DEFAULT = "Default";
    /**
     * String identifier of a file's "Status" property.
     */
    private static final String PROPERTY_STATUS = "Status";

    /**
     * String identifier of a file's "PDPs" property.
     */
    private static final String PROPERTY_PDPS = "PDPs";

    /**
     * String identifier of a file's "Policies" property.
     */
    private static final String PROPERTY_POLICIES = "Policies";

    /**
     * String identifier of a file's "PIP Configurations" property.
     */
    private static final String PROPERTY_PIPCONFIG = "PIP Configurations";

    /**
     * String identifier of a file's "Selected" property.
     */
    private static final String PROPERTY_SELECTED = "Selected";

    /**
     * List of the string identifiers for the available properties.
     */
    private static Collection<String> pDPProperties;

    private transient PAPPolicyEngine papEngine = null;
    protected transient List<OnapPDPGroup> groups = Collections.synchronizedList(new ArrayList<OnapPDPGroup>());

    public PDPGroupContainer(PAPPolicyEngine papPolicyEngine) {
        super();
        this.setContainer(this);
        //
        //
        //
        this.papEngine = papPolicyEngine;
        //
        //
        //
        this.refreshGroups();
    }

    public boolean isSupported(Object itemId) {
        return itemId instanceof OnapPDPGroup;
    }

    /**
     * refreshGroups.
     */
    public synchronized void refreshGroups() {
        synchronized (this.groups) {
            this.groups.clear();
            try {
                this.groups.addAll(this.papEngine.getOnapPDPGroups());
            } catch (PAPException e) {
                String message = "Unable to retrieve Groups from server: " + e;
                LOGGER.error(XACMLErrorConstants.ERROR_PROCESS_FLOW + message, e);
            }
            LOGGER.info("refreshGroups");
        }
        //
        // Notify that we have changed
        //
        this.fireItemSetChange();
    }

    public List<OnapPDPGroup> getGroups() {
        return Collections.unmodifiableList(this.groups);
    }

    /**
     * makeDefault.
     *
     * @param group OnapPDPGroup
     */
    public void makeDefault(OnapPDPGroup group) {
        try {
            this.papEngine.setDefaultGroup(group);
        } catch (PAPException e) {
            String message = "Unable to set Default Group on server: " + e;
            LOGGER.error(XACMLErrorConstants.ERROR_PROCESS_FLOW + message, e);
        }
        return;
    }

    /**
     * removeGroup.
     *
     * @param group OnapPDPGroup
     * @param newGroup OnapPDPGroup
     * @throws PAPException PAPException
     */
    public void removeGroup(OnapPDPGroup group, OnapPDPGroup newGroup) throws PAPException {
        if (LOGGER.isTraceEnabled()) {
            LOGGER.trace("removeGroup: " + group + " new group for PDPs: " + newGroup);
        }
        if (group.isDefaultGroup()) {
            throw new UnsupportedOperationException("You can't remove the Default Group.");
        }
        try {
            this.papEngine.removeGroup(group, newGroup);
        } catch (NullPointerException | PAPException e) {
            LOGGER.error(XACMLErrorConstants.ERROR_PROCESS_FLOW + "Failed to removeGroup " + group.getId(), e);
            throw new PAPException("Failed to remove group '" + group.getId() + "'", e);
        }
    }

    /**
     * removePDP.
     *
     * @param pdp OnapPDP
     * @param group OnapPDPGroup
     * @throws PAPException PAPException
     */
    public void removePDP(OnapPDP pdp, OnapPDPGroup group) throws PAPException {
        if (LOGGER.isTraceEnabled()) {
            LOGGER.trace("removePDP: " + pdp + " from group: " + group);
        }
        try {
            this.papEngine.removePDP(pdp);
        } catch (PAPException e) {
            LOGGER.error(XACMLErrorConstants.ERROR_PROCESS_FLOW + "Failed to removePDP " + pdp.getId(), e);
            throw new PAPException("Failed to remove pdp '" + pdp.getId() + "'", e);
        }
    }

    /**
     * updatePDP.
     *
     * @param pdp OnapPDP
     */
    public void updatePDP(OnapPDP pdp) {
        try {
            papEngine.updatePDP(pdp);
        } catch (PAPException e) {
            LOGGER.error(XACMLErrorConstants.ERROR_PROCESS_FLOW + e);
        }
    }

    /**
     * updateGroup.
     *
     * @param group OnapPDPGroup
     */
    public void updateGroup(OnapPDPGroup group) {
        try {
            papEngine.updateGroup(group);
        } catch (PAPException e) {
            LOGGER.error(XACMLErrorConstants.ERROR_PROCESS_FLOW + e);
        }
    }

    /**
     * Update group.
     *
     * @param group the group
     * @param userName the user name
     */
    public void updateGroup(OnapPDPGroup group, String userName) {
        try {
            papEngine.updateGroup(group, userName);
        } catch (PAPException e) {
            LOGGER.error(XACMLErrorConstants.ERROR_PROCESS_FLOW + e);
        }
    }

    @Override
    public Collection<?> getContainerPropertyIds() {
        return pDPProperties;
    }

    @Override
    public Collection<?> getItemIds() {
        final Collection<Object> items = new ArrayList<>();
        items.addAll(this.groups);
        if (LOGGER.isTraceEnabled()) {
            LOGGER.trace("getItemIds: " + items);
        }
        return Collections.unmodifiableCollection(items);
    }

    @Override
    public List<?> getItemIds(int startIndex, int numberOfItems) {
        synchronized (this.groups) {
            int endIndex = startIndex + numberOfItems;
            if (endIndex > this.groups.size()) {
                endIndex = this.groups.size() - 1;
            }
            return this.groups.subList(startIndex, endIndex);
        }
    }

    @Override
    public Class<?> getType(Object propertyId) {
        if (propertyId.equals(PROPERTY_ID)) {
            return String.class;
        }
        if (propertyId.equals(PROPERTY_NAME)) {
            return String.class;
        }
        if (propertyId.equals(PROPERTY_DESCRIPTION)) {
            return String.class;
        }
        if (propertyId.equals(PROPERTY_DEFAULT)) {
            return Boolean.class;
        }
        if (propertyId.equals(PROPERTY_STATUS)) {
            return String.class;
        }
        if (propertyId.equals(PROPERTY_PDPS)) {
            return Set.class;
        }
        if (propertyId.equals(PROPERTY_POLICIES)) {
            return Set.class;
        }
        if (propertyId.equals(PROPERTY_PIPCONFIG)) {
            return Set.class;
        }
        if (propertyId.equals(PROPERTY_SELECTED)) {
            return Checkbox.class;
        }
        return null;
    }

    @Override
    public int size() {
        return this.groups.size();
    }

    @Override
    public boolean containsId(Object itemId) {
        if (LOGGER.isTraceEnabled()) {
            LOGGER.trace("containsId: " + itemId);
        }
        if (!this.isSupported(itemId)) {
            return false;
        }
        return this.groups.contains(itemId);
    }

    @Override
    public Object addItem() {
        throw new UnsupportedOperationException("PDP Container cannot add a given item.");
    }

    /**
     * addNewGroup.
     *
     * @param name String
     * @param description String
     * @throws PAPException PAPException
     */
    public void addNewGroup(String name, String description) throws PAPException {
        if (LOGGER.isTraceEnabled()) {
            LOGGER.trace("addNewGroup " + name + " " + description);
        }
        this.papEngine.newGroup(name, description);
    }

    /**
     * addNewPDP.
     *
     * @param id String
     * @param group OnapPDPGroup
     * @param name String
     * @param description String
     * @param jmxport int
     * @throws PAPException PAPException
     */
    public void addNewPDP(String id, OnapPDPGroup group, String name, String description, int jmxport)
            throws PAPException {
        if (LOGGER.isTraceEnabled()) {
            LOGGER.trace("addNewPDP " + id + " " + name + " " + description + " " + jmxport);
        }
        this.papEngine.newPDP(id, group, name, description, jmxport);
    }

    /**
     * movePDP.
     *
     * @param pdp OnapPDP
     * @param group OnapPDPGroup
     */
    public void movePDP(OnapPDP pdp, OnapPDPGroup group) {
        try {
            this.papEngine.movePDP(pdp, group);
        } catch (PAPException e) {
            String message = "Unable to move PDP to new group on server: " + e;
            LOGGER.error(XACMLErrorConstants.ERROR_PROCESS_FLOW + message, e);
        }
        return;
    }

    @Override
    public boolean addContainerProperty(Object propertyId, Class<?> type, Object defaultValue) {
        throw new UnsupportedOperationException("Cannot add a container property.");
    }

    @Override
    public boolean removeContainerProperty(Object propertyId) {
        throw new UnsupportedOperationException("Cannot remove a container property.");
    }

    @Override
    public boolean removeAllItems() {
        throw new UnsupportedOperationException(
                "PDP Container cannot remove all items. You must have at least the Default group.");
    }

    @Override
    public void addItemSetChangeListener(ItemSetChangeListener listener) {
        if (getItemSetChangeListeners() == null) {
            setItemSetChangeListeners(new LinkedList<PolicyContainer.ItemSetChangeListener>());
        }
        getItemSetChangeListeners().add(listener);
    }

    @Override
    public Object nextItemId(Object itemId) {
        if (!this.isSupported(itemId)) {
            return null;
        }
        int index = this.groups.indexOf(itemId);
        if (index == -1) {
            //
            // We don't know this group
            //
            return null;
        }
        //
        // Is it the last one?
        //
        if (index == this.groups.size() - 1) {
            //
            // Yes
            //
            return null;
        }
        //
        // Return the next one
        //
        return this.groups.get(index + 1);
    }

    @Override
    public Object prevItemId(Object itemId) {
        if (!this.isSupported(itemId)) {
            return null;
        }
        int index = this.groups.indexOf(itemId);
        if (index == -1) {
            //
            // We don't know this group
            //
            return null;
        }
        //
        // Is it the first one?
        //
        if (index == 0) {
            //
            // Yes
            //
            return null;
        }
        //
        // Return the previous one
        //
        return this.groups.get(index - 1);
    }

    @Override
    public Object firstItemId() {
        synchronized (this.groups) {
            if (!this.groups.isEmpty()) {
                return this.groups.get(0);
            }
        }
        return null;
    }

    @Override
    public Object lastItemId() {
        synchronized (this.groups) {
            if (!this.groups.isEmpty()) {
                return this.groups.get(this.groups.size() - 1);
            }
        }
        return null;
    }

    @Override
    public boolean isFirstId(Object itemId) {
        synchronized (this.groups) {
            if (!this.groups.isEmpty()) {
                return this.groups.get(0).equals(itemId);
            }
        }
        return false;
    }

    @Override
    public boolean isLastId(Object itemId) {
        synchronized (this.groups) {
            if (!this.groups.isEmpty()) {
                return this.groups.get(this.groups.size() - 1).equals(itemId);
            }
        }
        return false;
    }

    @Override
    public Object addItemAfter(Object previousItemId) {
        throw new UnsupportedOperationException("Cannot addItemAfter, there really is no real ordering.");
    }

    @Override
    public int indexOfId(Object itemId) {
        return this.groups.indexOf(itemId);
    }

    @Override
    public Object getIdByIndex(int index) {
        return this.groups.get(index);
    }

    @Override
    public Object addItemAt(int index) {
        throw new UnsupportedOperationException("Cannot addItemAt");
    }

    @Override
    public boolean removeItem(Object itemId) {
        if (LOGGER.isTraceEnabled()) {
            LOGGER.trace("removeItem: " + itemId);
        }
        if (!this.isSupported(itemId)) {
            return false;
        }
        //
        // You cannot remove the default group
        //
        if (PROPERTY_DEFAULT.equals(((OnapPDPGroup) itemId).getId())) {
            throw new UnsupportedOperationException("You can't remove the Default Group.");
        }
        //
        // Remove PDPGroup and move any PDP's in it into the default group
        //
        try {
            this.papEngine.removeGroup((OnapPDPGroup) itemId, this.papEngine.getDefaultGroup());
            return true;
        } catch (NullPointerException | PAPException e) {
            LOGGER.error(XACMLErrorConstants.ERROR_PROCESS_FLOW + "Failed to remove group", e);
        }
        return false;
    }
}