/*******************************************************************************
 * ============LICENSE_START==================================================
 * * org.onap.dmaap
 * * ===========================================================================
 * * Copyright © 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====================================================
 * *
 * * ECOMP is a trademark and service mark of AT&T Intellectual Property.
 * *
 ******************************************************************************/

package org.onap.dmaap.datarouter.provisioning.beans;

import com.att.eelf.configuration.EELFLogger;
import com.att.eelf.configuration.EELFManager;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Collection;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;
import java.util.TreeSet;
import org.onap.dmaap.datarouter.provisioning.utils.ProvDbUtils;

/**
 * This class is used to aid in the mapping of node names from/to node IDs.
 *
 * @author Robert P. Eby
 * @version $Id: NodeClass.java,v 1.2 2014/01/15 16:08:43 eby Exp $
 */

public abstract class NodeClass extends Syncable {

    private static final String PROV_0005_DO_INSERT = "PROV0005 doInsert: ";
    private static Map<String, Integer> nodesMap;
    private static EELFLogger intLogger = EELFManager.getInstance().getLogger("InternalLog");

    NodeClass() {
        // init on first use
        if (nodesMap == null) {
            reload();
        }
    }

    /**
     * Add nodes to the NODES table, when the NODES parameter value is changed. Nodes are only added to the table, they
     * are never deleted.  The node name is normalized to contain the domain (if missing).
     *
     * @param nodes a pipe separated list of the current nodes
     */
    public static void setNodes(String[] nodes) {
        if (nodesMap == null) {
            reload();
        }
        int nextid = 0;
        for (Integer n : nodesMap.values()) {
            if (n >= nextid) {
                nextid = n + 1;
            }
        }
        // take | separated list, add domain if needed.

        for (String node : nodes) {
            node = normalizeNodename(node);
            if (!nodesMap.containsKey(node)) {
                intLogger.info("..adding " + node + " to NODES with index " + nextid);
                nodesMap.put(node, nextid);
                insertNodesToTable(nextid, node);
                nextid++;
            }
        }
    }

    private static void insertNodesToTable(int nextid, String node) {
        try (Connection conn = ProvDbUtils.getInstance().getConnection();
            PreparedStatement ps = conn.prepareStatement(
                "insert into NODES (NODEID, NAME, ACTIVE) values (?, ?, 1)")) {
            ps.setInt(1, nextid);
            ps.setString(2, node);
            ps.execute();
        } catch (SQLException e) {
            intLogger.error(PROV_0005_DO_INSERT + e.getMessage(), e);
        }
    }

    private static void reload() {
        Map<String, Integer> tmpNodesMap = new HashMap<>();
        try (Connection conn = ProvDbUtils.getInstance().getConnection();
            PreparedStatement ps = conn.prepareStatement("select NODEID, NAME from NODES");
            ResultSet rs = ps.executeQuery()) {
            while (rs.next()) {
                int id = rs.getInt("NODEID");
                String name = rs.getString("NAME");
                tmpNodesMap.put(name, id);
            }
        } catch (SQLException e) {
            intLogger.error(PROV_0005_DO_INSERT + e.getMessage(),e);
        }
        nodesMap = tmpNodesMap;
    }

    static Integer lookupNodeName(final String name) {
        Integer nodeName = nodesMap.get(name);
        if (nodeName == null) {
            throw new IllegalArgumentException("Invalid node name: " + name);
        }
        return nodeName;
    }

    /**
     * Get node names.
     * @param patt pattern to search
     * @return collection of node names
     */
    public static Collection<String> lookupNodeNames(String patt) {
        Collection<String> coll = new TreeSet<>();
        final Set<String> keyset = nodesMap.keySet();
        for (String s : patt.toLowerCase().split(",")) {
            if (s.endsWith("*")) {
                addNodeToCollection(coll, keyset, s);
            } else if (keyset.contains(s)) {
                coll.add(s);
            } else if (keyset.contains(normalizeNodename(s))) {
                coll.add(normalizeNodename(s));
            } else {
                throw new IllegalArgumentException("Invalid node name: " + s);
            }
        }
        return coll;
    }

    private static void addNodeToCollection(Collection<String> coll, Set<String> keyset, String str) {
        str = str.substring(0, str.length() - 1);
        for (String s2 : keyset) {
            if (s2.startsWith(str)) {
                coll.add(s2);
            }
        }
    }

    /**
     * Method to add domain name.
     * @param str nde name string
     * @return normalized node name
     */
    public static String normalizeNodename(String str) {
        if (str != null && str.indexOf('.') <= 0) {
            Parameters param = Parameters.getParameter(Parameters.PROV_DOMAIN);
            if (param != null) {
                String domain = param.getValue();
                str += "." + domain;
            }
            return str.toLowerCase();
        } else {
            return str;
        }

    }

    String lookupNodeID(int node) {
        for (Map.Entry<String, Integer> entry : nodesMap.entrySet()) {
            if (entry.getValue() == node) {
                return entry.getKey();
            }
        }
        return null;
    }
}