node-nlp/examples/microsoft-bot/node_modules/chrono-node/src/parsers/EN/ENISOFormatParser.js

Library for NLU (Natural Language Understanding) done in Node.js

/*
    ISO 8601
    http://www.w3.org/TR/NOTE-datetime
    - YYYY-MM-DD
    - YYYY-MM-DDThh:mmTZD
    - YYYY-MM-DDThh:mm:ssTZD
    - YYYY-MM-DDThh:mm:ss.sTZD 
    - TZD = (Z or +hh:mm or -hh:mm)
*/
var moment = require('moment');
var Parser = require('../parser').Parser;
var ParsedResult = require('../../result').ParsedResult;

var PATTERN = new RegExp('(\\W|^)' 
            + '([0-9]{4})\\-([0-9]{1,2})\\-([0-9]{1,2})'
            + '(?:T' //..
                + '([0-9]{1,2}):([0-9]{1,2})' // hh:mm
                + '(?::([0-9]{1,2})(?:\\.(\\d{1,4}))?)?' // :ss.s
                + '(?:Z|([+-]\\d{2}):?(\\d{2})?)?' // TZD (Z or ±hh:mm or ±hhmm or ±hh)
            + ')?'  //..
            + '(?=\\W|$)', 'i');

var YEAR_NUMBER_GROUP = 2;
var MONTH_NUMBER_GROUP = 3;
var DATE_NUMBER_GROUP  = 4;
var HOUR_NUMBER_GROUP  = 5;
var MINUTE_NUMBER_GROUP = 6;
var SECOND_NUMBER_GROUP = 7;
var MILLISECOND_NUMBER_GROUP = 8;
var TZD_HOUR_OFFSET_GROUP = 9;
var TZD_MINUTE_OFFSET_GROUP = 10;

exports.Parser = function ENISOFormatParser(){
    Parser.apply(this, arguments);
    
    this.pattern = function() { return PATTERN; }
    
    this.extract = function(text, ref, match, opt){ 
        
        var text = match[0].substr(match[1].length);
        var index = match.index + match[1].length;

        var result = new ParsedResult({
            text: text,
            index: index,
            ref: ref,
        })
        
        result.start.assign('year', parseInt(match[YEAR_NUMBER_GROUP]));
        result.start.assign('month', parseInt(match[MONTH_NUMBER_GROUP]));
        result.start.assign('day', parseInt(match[DATE_NUMBER_GROUP]));

        if (moment(result.start.get('month')) > 12 || moment(result.start.get('month')) < 1 ||
            moment(result.start.get('day')) > 31 || moment(result.start.get('day')) < 1) {
            return null;
        }

        if (match[HOUR_NUMBER_GROUP] != null) {
            
            result.start.assign('hour',
                    parseInt(match[HOUR_NUMBER_GROUP]));
            result.start.assign('minute',
                    parseInt(match[MINUTE_NUMBER_GROUP]));

            if (match[SECOND_NUMBER_GROUP] != null) {

                result.start.assign('second',
                        parseInt(match[SECOND_NUMBER_GROUP]));
            }

            if (match[MILLISECOND_NUMBER_GROUP] != null) {

                result.start.assign('millisecond',
                        parseInt(match[MILLISECOND_NUMBER_GROUP]));
            }

            if (match[TZD_HOUR_OFFSET_GROUP] == null) {

                result.start.assign('timezoneOffset', 0);
            } else {

                var minuteOffset = 0;
                var hourOffset = parseInt(match[TZD_HOUR_OFFSET_GROUP]);
                if (match[TZD_MINUTE_OFFSET_GROUP] != null)
                    minuteOffset = parseInt(match[TZD_MINUTE_OFFSET_GROUP]);

                var offset = hourOffset * 60;
                if (offset < 0) {
                    offset -= minuteOffset;
                } else {
                    offset += minuteOffset;
                }

                result.start.assign('timezoneOffset', offset);
            }
        }
        
        result.tags['ENISOFormatParser'] = true;
        return result;
    };

}