/*
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* Copyright 2008 ZXing authors
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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/*namespace com.google.zxing.oned {*/
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import BarcodeFormat from '../BarcodeFormat';
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import NotFoundException from '../NotFoundException';
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import OneDReader from './OneDReader';
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import Result from '../Result';
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import ResultPoint from '../ResultPoint';
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/**
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* <p>Decodes CodaBar barcodes. </p>
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*
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* @author Evan @dodobelieve
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* @see CodaBarReader
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*/
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export default class CodaBarReader extends OneDReader {
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constructor() {
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super(...arguments);
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this.CODA_BAR_CHAR_SET = {
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nnnnnww: '0',
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nnnnwwn: '1',
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nnnwnnw: '2',
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wwnnnnn: '3',
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nnwnnwn: '4',
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wnnnnwn: '5',
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nwnnnnw: '6',
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nwnnwnn: '7',
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nwwnnnn: '8',
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wnnwnnn: '9',
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nnnwwnn: '-',
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nnwwnnn: '$',
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wnnnwnw: ':',
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wnwnnnw: '/',
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wnwnwnn: '.',
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nnwwwww: '+',
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nnwwnwn: 'A',
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nwnwnnw: 'B',
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nnnwnww: 'C',
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nnnwwwn: 'D'
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};
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}
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decodeRow(rowNumber, row, hints) {
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let validRowData = this.getValidRowData(row);
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if (!validRowData)
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throw new NotFoundException();
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let retStr = this.codaBarDecodeRow(validRowData.row);
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if (!retStr)
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throw new NotFoundException();
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return new Result(retStr, null, 0, [new ResultPoint(validRowData.left, rowNumber), new ResultPoint(validRowData.right, rowNumber)], BarcodeFormat.CODABAR, new Date().getTime());
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}
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/**
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* converts bit array to valid data array(lengths of black bits and white bits)
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* @param row bit array to convert
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*/
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getValidRowData(row) {
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let booleanArr = row.toArray();
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let startIndex = booleanArr.indexOf(true);
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if (startIndex === -1)
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return null;
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let lastIndex = booleanArr.lastIndexOf(true);
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if (lastIndex <= startIndex)
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return null;
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booleanArr = booleanArr.slice(startIndex, lastIndex + 1);
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let result = [];
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let lastBit = booleanArr[0];
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let bitLength = 1;
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for (let i = 1; i < booleanArr.length; i++) {
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if (booleanArr[i] === lastBit) {
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bitLength++;
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}
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else {
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lastBit = booleanArr[i];
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result.push(bitLength);
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bitLength = 1;
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}
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}
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result.push(bitLength);
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// CodaBar code data valid
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if (result.length < 23 && (result.length + 1) % 8 !== 0)
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return null;
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return { row: result, left: startIndex, right: lastIndex };
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}
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/**
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* decode codabar code
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* @param row row to cecode
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*/
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codaBarDecodeRow(row) {
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const code = [];
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const barThreshold = Math.ceil(row.reduce((pre, item) => (pre + item) / 2, 0));
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// Read one encoded character at a time.
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while (row.length > 0) {
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const seg = row.splice(0, 8).splice(0, 7);
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const key = seg.map(len => (len < barThreshold ? 'n' : 'w')).join('');
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if (this.CODA_BAR_CHAR_SET[key] === undefined)
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return null;
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code.push(this.CODA_BAR_CHAR_SET[key]);
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}
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let strCode = code.join('');
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if (this.validCodaBarString(strCode))
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return strCode;
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return null;
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}
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/**
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* check if the string is a CodaBar string
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* @param src string to determine
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*/
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validCodaBarString(src) {
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let reg = /^[A-D].{1,}[A-D]$/;
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return reg.test(src);
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}
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}
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