/*
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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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import UPCEANReader from './UPCEANReader';
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import StringBuilder from '../util/StringBuilder';
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import NotFoundException from '../NotFoundException';
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import BarcodeFormat from '../BarcodeFormat';
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// package com.google.zxing.oned;
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// import com.google.zxing.BarcodeFormat;
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// import com.google.zxing.FormatException;
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// import com.google.zxing.NotFoundException;
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// import com.google.zxing.common.BitArray;
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/**
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* <p>Implements decoding of the UPC-E format.</p>
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* <p><a href="http://www.barcodeisland.com/upce.phtml">This</a> is a great reference for
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* UPC-E information.</p>
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*
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* @author Sean Owen
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*
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* @source https://github.com/zxing/zxing/blob/3c96923276dd5785d58eb970b6ba3f80d36a9505/core/src/main/java/com/google/zxing/oned/UPCEReader.java
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*
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* @experimental
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*/
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export default /* final */ class UPCEReader extends UPCEANReader {
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constructor() {
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super();
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this.decodeMiddleCounters = new Int32Array(4);
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}
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/**
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* @throws NotFoundException
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*/
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// @Override
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decodeMiddle(row, startRange, result) {
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const counters = this.decodeMiddleCounters.map(x => x);
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counters[0] = 0;
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counters[1] = 0;
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counters[2] = 0;
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counters[3] = 0;
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const end = row.getSize();
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let rowOffset = startRange[1];
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let lgPatternFound = 0;
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for (let x = 0; x < 6 && rowOffset < end; x++) {
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const bestMatch = UPCEReader.decodeDigit(row, counters, rowOffset, UPCEReader.L_AND_G_PATTERNS);
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result += String.fromCharCode(('0'.charCodeAt(0) + bestMatch % 10));
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for (let counter of counters) {
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rowOffset += counter;
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}
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if (bestMatch >= 10) {
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lgPatternFound |= 1 << (5 - x);
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}
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}
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UPCEReader.determineNumSysAndCheckDigit(new StringBuilder(result), lgPatternFound);
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return rowOffset;
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}
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/**
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* @throws NotFoundException
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*/
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// @Override
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decodeEnd(row, endStart) {
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return UPCEReader.findGuardPatternWithoutCounters(row, endStart, true, UPCEReader.MIDDLE_END_PATTERN);
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}
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/**
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* @throws FormatException
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*/
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// @Override
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checkChecksum(s) {
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return UPCEANReader.checkChecksum(UPCEReader.convertUPCEtoUPCA(s));
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}
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/**
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* @throws NotFoundException
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*/
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static determineNumSysAndCheckDigit(resultString, lgPatternFound) {
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for (let numSys = 0; numSys <= 1; numSys++) {
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for (let d = 0; d < 10; d++) {
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if (lgPatternFound === this.NUMSYS_AND_CHECK_DIGIT_PATTERNS[numSys][d]) {
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resultString.insert(0, /*(char)*/ ('0' + numSys));
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resultString.append(/*(char)*/ ('0' + d));
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return;
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}
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}
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}
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throw NotFoundException.getNotFoundInstance();
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}
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// @Override
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getBarcodeFormat() {
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return BarcodeFormat.UPC_E;
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}
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/**
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* Expands a UPC-E value back into its full, equivalent UPC-A code value.
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*
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* @param upce UPC-E code as string of digits
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* @return equivalent UPC-A code as string of digits
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*/
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static convertUPCEtoUPCA(upce) {
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// the following line is equivalent to upce.getChars(1, 7, upceChars, 0);
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const upceChars = upce.slice(1, 7).split('').map(x => x.charCodeAt(0));
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const result = new StringBuilder( /*12*/);
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result.append(upce.charAt(0));
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let lastChar = upceChars[5];
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switch (lastChar) {
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case 0:
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case 1:
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case 2:
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result.appendChars(upceChars, 0, 2);
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result.append(lastChar);
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result.append('0000');
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result.appendChars(upceChars, 2, 3);
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break;
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case 3:
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result.appendChars(upceChars, 0, 3);
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result.append('00000');
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result.appendChars(upceChars, 3, 2);
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break;
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case 4:
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result.appendChars(upceChars, 0, 4);
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result.append('00000');
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result.append(upceChars[4]);
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break;
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default:
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result.appendChars(upceChars, 0, 5);
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result.append('0000');
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result.append(lastChar);
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break;
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}
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// Only append check digit in conversion if supplied
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if (upce.length >= 8) {
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result.append(upce.charAt(7));
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}
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return result.toString();
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}
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}
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/**
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* The pattern that marks the middle, and end, of a UPC-E pattern.
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* There is no "second half" to a UPC-E barcode.
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*/
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UPCEReader.MIDDLE_END_PATTERN = Int32Array.from([1, 1, 1, 1, 1, 1]);
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// For an UPC-E barcode, the final digit is represented by the parities used
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// to encode the middle six digits, according to the table below.
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//
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// Parity of next 6 digits
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// Digit 0 1 2 3 4 5
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// 0 Even Even Even Odd Odd Odd
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// 1 Even Even Odd Even Odd Odd
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// 2 Even Even Odd Odd Even Odd
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// 3 Even Even Odd Odd Odd Even
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// 4 Even Odd Even Even Odd Odd
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// 5 Even Odd Odd Even Even Odd
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// 6 Even Odd Odd Odd Even Even
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// 7 Even Odd Even Odd Even Odd
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// 8 Even Odd Even Odd Odd Even
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// 9 Even Odd Odd Even Odd Even
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//
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// The encoding is represented by the following array, which is a bit pattern
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// using Odd = 0 and Even = 1. For example, 5 is represented by:
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//
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// Odd Even Even Odd Odd Even
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// in binary:
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// 0 1 1 0 0 1 == 0x19
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//
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/**
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* See {@link #L_AND_G_PATTERNS}; these values similarly represent patterns of
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* even-odd parity encodings of digits that imply both the number system (0 or 1)
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* used, and the check digit.
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*/
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UPCEReader.NUMSYS_AND_CHECK_DIGIT_PATTERNS = [
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Int32Array.from([0x38, 0x34, 0x32, 0x31, 0x2C, 0x26, 0x23, 0x2A, 0x29, 0x25]),
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Int32Array.from([0x07, 0x0B, 0x0D, 0x0E, 0x13, 0x19, 0x1C, 0x15, 0x16, 0x1]),
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];
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