/*
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 * Copyright (c) 2019, NTT Ltd.
 * All rights reserved.
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 * modification, are permitted provided that the following conditions are met:
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 *  Redistributions of source code must retain the above copyright notice, this
 *   list of conditions and the following disclaimer.
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 *   this software without specific prior written permission.
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 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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import Monitor from "./monitor";

export default class MonitorNewPrefix extends Monitor {

    constructor(name, channel, params, env){
        super(name, channel, params, env);
        this.thresholdMinPeers = (params && params.thresholdMinPeers != null) ? params.thresholdMinPeers : 2;
        this.updateMonitoredPrefixes();
    };

    updateMonitoredPrefixes = () => {
        this.monitored = this.input.getMonitoredMoreSpecifics();
    };

    filter = (message) => {
        return message.type === 'announcement';
    };

    squashAlerts = (alerts) => {
        const peers = [...new Set(alerts.map(alert => alert.matchedMessage.peer))].length;

        if (peers >= this.thresholdMinPeers) {
            return alerts[0].message;
        }

        return false;
    };

    monitor = (message) =>
        new Promise((resolve, reject) => {

            const messagePrefix = message.prefix;
            const matchedRule = this.getMoreSpecificMatch(messagePrefix);

            if (matchedRule && matchedRule.asn.includes(message.originAS) && matchedRule.prefix !== messagePrefix) {
                const text = `Possible change of configuration. A new prefix ${message.prefix} is announced by ${message.originAS}. It is a more specific of ${matchedRule.prefix} (${matchedRule.description}).`;

                this.publishAlert(message.originAS.getId() + "-" + message.prefix,
                    text,
                    matchedRule.asn.getId(),
                    matchedRule,
                    message,
                    {});
            }

            resolve(true);
        });

}