/*
 * Copyright (C) 2016-2020 phantombot.github.io/PhantomBot
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

/**
 * patterDetector.js
 *
 * Export an API for checking chat messages for links, email addresses, excessive character sequenses etc.
 * Use the $.patternDetector API
 */
(function() {
    var patterns = {
        link: new RegExp('((?:(http|https|rtsp):\\/\\/(?:(?:[a-z0-9\\$\\-\\_\\.\\+\\!\\*\\\'\\(\\)' + '\\,\\;\\?\\&\\=]|(?:\\%[a-fA-F0-9]{2})){1,64}(?:\\:(?:[a-z0-9\\$\\-\\_' + '\\.\\+\\!\\*\\\'\\(\\)\\,\\;\\?\\&\\=]|(?:\\%[a-fA-F0-9]{2})){1,25})?\\@)?)?' + '((?:(?:[a-z0-9][a-z0-9\\-]{0,64}\\.)+' + '(?:' + '(?:aero|a[cdefgilmnoqrstuwxz])' + '|(?:biz|bike|bot|b[abdefghijmnorstvwyz])' + '|(?:com|c[acdfghiklmnoruvxyz])' + '|d[ejkmoz]' + '|(?:edu|e[cegrstu])' + '|(?:fyi|f[ijkmor])' + '|(?:gov|g[abdefghilmnpqrstuwy])' + '|(?:how|h[kmnrtu])' + '|(?:info|i[delmnoqrst])' + '|(?:jobs|j[emop])' + '|k[eghimnrwyz]' + '|l[abcikrstuvy]' + '|(?:mil|mobi|moe|m[acdeghklmnopqrstuvwxyz])' + '|(?:name|net|n[acefgilopruz])' + '|(?:org|om)' + '|(?:pro|p[aefghklmnrstwy])' + '|qa' + '|(?:r[eouw])' + '|(?:s[abcdeghijklmnortuvyz])' + '|(?:t[cdfghjklmnoprtvwz])' + '|u[agkmsyz]' + '|(?:vote|v[ceginu])' + '|(?:xxx)' + '|(?:watch|w[fs])' + '|y[etu]' + '|z[amw]))' + '|(?:(?:25[0-5]|2[0-4]' + '[0-9]|[0-1][0-9]{2}|[1-9][0-9]|[1-9])\\.(?:25[0-5]|2[0-4][0-9]' + '|[0-1][0-9]{2}|[1-9][0-9]|[1-9]|0)\\.(?:25[0-5]|2[0-4][0-9]|[0-1]' + '[0-9]{2}|[1-9][0-9]|[1-9]|0)\\.(?:25[0-5]|2[0-4][0-9]|[0-1][0-9]{2}' + '|[1-9][0-9]|[0-9])))' + '(?:\\:\\d{1,5})?)' + '(\\/(?:(?:[a-z0-9\\;\\/\\?\\:\\@\\&\\=\\#\\~' + '\\-\\.\\+\\!\\*\\\'\\(\\)\\,\\_])|(?:\\%[a-fA-F0-9]{2}))*)?' + '(?:\\b|$)' + '|(\\.[a-z]+\\/|magnet:\/\/|mailto:\/\/|ed2k:\/\/|irc:\/\/|ircs:\/\/|skype:\/\/|ymsgr:\/\/|xfire:\/\/|steam:\/\/|aim:\/\/|spotify:\/\/)', 'ig'),
        emotes: new RegExp('([0-9][0-9]-[0-9][0-9])|([0-9]-[0-9])', 'g'),
        repeatedSeq: /(.)(\1+)/ig,
        nonAlphaSeq: /([^a-z0-9 ])(\1+)/ig,
        nonAlphaCount: /([^a-z0-9 ])/ig,
        capsCount: /([A-Z])/g,
        meCheck: /^\/me/,
        fakePurge: new RegExp(/^<message \w+>|^<\w+ deleted>/i)
    };

    /**
     * @function hasLinks
     * @export $.patternDetector
     * @param {Object} event
     * @returns {boolean}
     */
    function hasLinks(event) {
        return $.test(event.getMessage(), patterns.link);
    }

    /**
     * @function getLinks
     * @export $.patternDetector
     * @param {String} message
     * @returns {string[]}
     */
    function getLinks(message) {
        // turn Java String into JavaScript string
        // https://github.com/mozilla/rhino/issues/638
        message = message + '';
        return $.match(message, patterns.link);
    }

    /**
     * @function logLastLink
     * @export $.patternDetector
     */
    function logLastLink(event) {
        $.log.file('patternDetector', 'Matched link on message from ' + event.getSender() + ': ' + $.regexExec(event.getMessage(), patterns.link)[0]);
    }

    /**
     * @function getLongestRepeatedSequence
     * @export $.patternDetector
     * @param {Object} event
     * @returns {number}
     */
    function getLongestRepeatedSequence(event) {
        var sequences = $.match(event.getMessage(), patterns.repeatedSeq);

        return (sequences === null ? 0 : sequences.sort(function(a, b) {
            return b.length - a.length;
        })[0].length);
    }

    /**
     * @function getLongestNonLetterSequence
     * @export $.patternDetector
     * @param {Object} event
     * @returns {number}
     */
    function getLongestNonLetterSequence(event) {
        var message = (event.getMessage() + ''),
            sequences = $.match(message, patterns.nonAlphaSeq);

        return (sequences === null ? 0 : sequences.sort(function(a, b) {
            return b.length - a.length;
        })[0].length);
    }

    /**
     * @function getNumberOfNonLetters
     * @export $.patternDetector
     * @param {Object} event
     * @returns {number}
     */
    function getNumberOfNonLetters(event) {
        var sequences = $.match(event.getMessage(), patterns.nonAlphaCount);

        return (sequences === null ? 0 : sequences.length);
    }

    /**
     * @function getEmotesCount
     * @export $.patternDetector
     * @param {Object} event
     * @returns {number}
     * @info this gets the emote count from the ircv3 tags and the emotes cache if enabled.
     */
    function getEmotesCount(event) {
        var emotes = event.getTags().get('emotes'),
            matched = $.match(emotes, patterns.emotes),
            extraEmotes = $.emotesHandler.getEmotesMatchCount(event.getMessage());

        return (matched === null ? extraEmotes : (matched.length + extraEmotes));
    }

    /**
     * @function getMessageWithoutEmotes
     * @export $.patternDetector
     * @param {Object} event
     * @returns {string}
     */
    function getMessageWithoutEmotes(event, message) {
        var emotes = event.getTags().get('emotes'),
            str = message,
            i;

        if (emotes.length() > 0) {
            emotes = emotes.replaceAll('[0-9]+:', '').split('/');
            for (i in emotes) {
                str = str.replace(getWordAt(message, parseInt(emotes[i].split('-')[0])), '');
            }
        }
        return str;
    }

    /**
     * @function getWordAt
     *
     * @param  {String} str
     * @param  {Number} pos
     * @return {String}
     */
    function getWordAt(str, pos) {
        str = String(str);
        pos = pos >>> 0;

        var left = str.slice(0, pos + 2).search(/\S+$/),
            right = str.slice(pos).search(/\s/);

        if (right < 0) {
            return str.slice(left);
        }

        return str.slice(left, right + pos);
    }

    /**
     * @function getNumberOfCaps
     * @export $.patternDetector
     * @param {Object} event
     * @returns {number}
     */
    function getNumberOfCaps(event) {
        var sequences = $.match(getMessageWithoutEmotes(event, event.getMessage()), patterns.capsCount);

        return (sequences === null ? 0 : sequences.length);
    }

    /**
     * @function getColoredMessage
     * @export $.patternDetector
     * @param {Object} event
     * @returns {boolean}
     */
    function getColoredMessage(event) {
        return event.getMessage().indexOf('/me') === 0;
    }

    /**
     * @function getFakePurge
     * @export $.patternDetector
     * @param {Object} event
     * @returns {boolean}
     */
    function getFakePurge(event) {
        return $.test(String(event.getMessage()).replace(patterns.meCheck, ''), patterns.fakePurge);
    }

    /** Export functions to API */
    $.patternDetector = {
        hasLinks: hasLinks,
        getLinks: getLinks,
        getLongestRepeatedSequence: getLongestRepeatedSequence,
        getLongestNonLetterSequence: getLongestNonLetterSequence,
        getNumberOfNonLetters: getNumberOfNonLetters,
        getEmotesCount: getEmotesCount,
        getMessageWithoutEmotes: getMessageWithoutEmotes,
        getNumberOfCaps: getNumberOfCaps,
        logLastLink: logLastLink,
        getColoredMessage: getColoredMessage,
        getFakePurge: getFakePurge
    };
})();