/*
 *
 * MariaDB Client for Java
 *
 * Copyright (c) 2012-2014 Monty Program Ab.
 * Copyright (c) 2015-2017 MariaDB Ab.
 *
 * This library is free software; you can redistribute it and/or modify it under
 * the terms of the GNU Lesser General Public License as published by the Free
 * Software Foundation; either version 2.1 of the License, or (at your option)
 * any later version.
 *
 * This library is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
 * for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License along
 * with this library; if not, write to Monty Program Ab info@montyprogram.com.
 *
 * This particular MariaDB Client for Java file is work
 * derived from a Drizzle-JDBC. Drizzle-JDBC file which is covered by subject to
 * the following copyright and notice provisions:
 *
 * Copyright (c) 2009-2011, Marcus Eriksson
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 * Redistributions of source code must retain the above copyright notice, this list
 * of conditions and the following disclaimer.
 *
 * Redistributions in binary form must reproduce the above copyright notice, this
 * list of conditions and the following disclaimer in the documentation and/or
 * other materials provided with the distribution.
 *
 * Neither the name of the driver nor the names of its contributors may not be
 * used to endorse or promote products derived from this software without specific
 * prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS  AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
 * OF SUCH DAMAGE.
 *
 */

package org.mariadb.jdbc;

import org.mariadb.jdbc.internal.logging.Logger;
import org.mariadb.jdbc.internal.logging.LoggerFactory;
import org.mariadb.jdbc.internal.util.constant.HaMode;
import org.mariadb.jdbc.internal.util.constant.ParameterConstant;

import java.util.ArrayList;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class HostAddress {
    private static final Logger logger = LoggerFactory.getLogger(HostAddress.class);

    public String host;
    public int port;
    public String type = null;


    private HostAddress() {
    }

    /**
     * Constructor. type is master.
     *
     * @param host host
     * @param port port
     */
    public HostAddress(String host, int port) {
        this.host = host;
        this.port = port;
        this.type = ParameterConstant.TYPE_MASTER;
    }

    /**
     * Constructor.
     *
     * @param host host
     * @param port port
     * @param type type
     */
    public HostAddress(String host, int port, String type) {
        this.host = host;
        this.port = port;
        this.type = type;
    }

    /**
     * parse - parse server addresses from the URL fragment
     *
     * @param spec   - list of endpoints in one of the forms
     *               1 - host1,....,hostN:port (missing port default to MySQL default 3306
     *               2 - host:port,...,host:port
     * @param haMode High availability mode
     * @return parsed endpoints
     */
    public static List<HostAddress> parse(String spec, HaMode haMode) {
        if (spec == null) {
            throw new IllegalArgumentException("Invalid connection URL, host address must not be empty ");
        }
        if ("".equals(spec)) {
            return new ArrayList<>(0);
        }
        String[] tokens = spec.trim().split(",");
        int size = tokens.length;
        List<HostAddress> arr = new ArrayList<>(size);

        // Aurora using cluster end point mustn't have any other host
        if (haMode == HaMode.AURORA) {
            Pattern clusterPattern = Pattern.compile("(.+)\\.cluster-([a-z0-9]+\\.[a-z0-9\\-]+\\.rds\\.amazonaws\\.com)", Pattern.CASE_INSENSITIVE);
            Matcher matcher = clusterPattern.matcher(spec);

            if (!matcher.find()) {
                logger.warn("Aurora recommended connection URL must only use cluster end-point like "
                        + "\"jdbc:mariadb:aurora//xx.cluster-yy.zz.rds.amazonaws.com\". "
                        + "Using end-point permit auto-discovery of new replicas");
            }
        }

        for (String token : tokens) {
            if (token.startsWith("address=")) {
                arr.add(parseParameterHostAddress(token));
            } else {
                arr.add(parseSimpleHostAddress(token));
            }
        }

        if (haMode == HaMode.REPLICATION) {
            for (int i = 0; i < size; i++) {
                if (i == 0 && arr.get(i).type == null) {
                    arr.get(i).type = ParameterConstant.TYPE_MASTER;
                } else if (i != 0 && arr.get(i).type == null) {
                    arr.get(i).type = ParameterConstant.TYPE_SLAVE;
                }
            }
        }
        return arr;
    }

    private static HostAddress parseSimpleHostAddress(String str) {
        HostAddress result = new HostAddress();
        if (str.charAt(0) == '[') {
            /* IPv6 addresses in URLs are enclosed in square brackets */
            int ind = str.indexOf(']');
            result.host = str.substring(1, ind);
            if (ind != (str.length() - 1) && str.charAt(ind + 1) == ':') {
                result.port = getPort(str.substring(ind + 2));
            }
        } else if (str.contains(":")) {
              /* Parse host:port */
            String[] hostPort = str.split(":");
            result.host = hostPort[0];
            result.port = getPort(hostPort[1]);
        } else {
              /* Just host name is given */
            result.host = str;
            result.port = 3306;
        }
        return result;
    }

    private static int getPort(String portString) {
        try {
            return Integer.parseInt(portString);
        } catch (NumberFormatException nfe) {
            throw new IllegalArgumentException("Incorrect port value : " + portString);
        }
    }

    private static HostAddress parseParameterHostAddress(String str) {
        HostAddress result = new HostAddress();
        String[] array = str.split("(?=\\()|(?<=\\))");
        for (int i = 1; i < array.length; i++) {
            String[] token = array[i].replace("(", "").replace(")", "").trim().split("=");
            if (token.length != 2) {
                throw new IllegalArgumentException("Invalid connection URL, expected key=value pairs, found " + array[i]);
            }
            String key = token[0].toLowerCase();
            String value = token[1].toLowerCase();
            if ("host".equals(key)) {
                result.host = value.replace("[", "").replace("]", "");
            } else if ("port".equals(key)) {
                result.port = getPort(value);
            } else if ("type".equals(key)
                    && (value.equals(ParameterConstant.TYPE_MASTER) || value.equals(ParameterConstant.TYPE_SLAVE))) {
                result.type = value;
            }
        }
        return result;
    }

    /**
     * ToString implementation of addresses.
     *
     * @param addrs address list
     * @return String value
     */
    public static String toString(List<HostAddress> addrs) {
        StringBuilder str = new StringBuilder();
        for (int i = 0; i < addrs.size(); i++) {
            if (addrs.get(i).type != null) {
                str.append("address=(host=")
                        .append(addrs.get(i).host)
                        .append(")(port=")
                        .append(addrs.get(i).port)
                        .append(")(type=")
                        .append(addrs.get(i).type)
                        .append(")");
            } else {
                boolean isIPv6 = addrs.get(i).host != null && addrs.get(i).host.contains(":");
                String host = (isIPv6) ? ("[" + addrs.get(i).host + "]") : addrs.get(i).host;
                str.append(host).append(":").append(addrs.get(i).port);
            }
            if (i < addrs.size() - 1) {
                str.append(",");
            }
        }
        return str.toString();
    }

    /**
     * ToString implementation of addresses.
     *
     * @param addrs address array
     * @return String value
     */
    @SuppressWarnings("unused")
    public static String toString(HostAddress[] addrs) {
        StringBuilder str = new StringBuilder();
        for (int i = 0; i < addrs.length; i++) {
            if (addrs[i].type != null) {
                str.append("address=(host=")
                        .append(addrs[i].host)
                        .append(")(port=")
                        .append(addrs[i].port)
                        .append(")(type=")
                        .append(addrs[i].type)
                        .append(")");
            } else {
                boolean isIPv6 = addrs[i].host != null && addrs[i].host.contains(":");
                String host = (isIPv6) ? ("[" + addrs[i].host + "]") : addrs[i].host;
                str.append(host).append(":").append(addrs[i].port);
            }
            if (i < addrs.length - 1) {
                str.append(",");
            }
        }
        return str.toString();
    }

    @Override
    public String toString() {
        return "HostAddress{"
                + "host='" + host + '\''
                + ", port=" + port
                + ((type != null) ? (", type='" + type + "'") : "")
                + "}";
    }

    @Override
    public boolean equals(Object obj) {
        if (this == obj) {
            return true;
        }
        if (obj == null || getClass() != obj.getClass()) {
            return false;
        }

        HostAddress that = (HostAddress) obj;

        return port == that.port && (host != null ? host.equals(that.host) : that.host == null
                && !(type != null ? !type.equals(that.type) : that.type != null));

    }

    @Override
    public int hashCode() {
        int result = host != null ? host.hashCode() : 0;
        result = 31 * result + port;
        return result;
    }


}
