@zxing/library/es2015/core/datamatrix/encoder/X12Encoder.js

TypeScript port of ZXing multi-format 1D/2D barcode image processing library.

import StringUtils from '../../common/StringUtils';
import StringBuilder from '../../util/StringBuilder';
import { C40Encoder } from './C40Encoder';
import HighLevelEncoder from './HighLevelEncoder';
import { X12_ENCODATION, ASCII_ENCODATION, X12_UNLATCH } from './constants';
export class X12Encoder extends C40Encoder {
    getEncodingMode() {
        return X12_ENCODATION;
    }
    encode(context) {
        // step C
        const buffer = new StringBuilder();
        while (context.hasMoreCharacters()) {
            const c = context.getCurrentChar();
            context.pos++;
            this.encodeChar(c, buffer);
            const count = buffer.length();
            if (count % 3 === 0) {
                this.writeNextTriplet(context, buffer);
                const newMode = HighLevelEncoder.lookAheadTest(context.getMessage(), context.pos, this.getEncodingMode());
                if (newMode !== this.getEncodingMode()) {
                    // Return to ASCII encodation, which will actually handle latch to new mode
                    context.signalEncoderChange(ASCII_ENCODATION);
                    break;
                }
            }
        }
        this.handleEOD(context, buffer);
    }
    encodeChar(c, sb) {
        switch (c) {
            case 13: // CR (Carriage return)
                sb.append(0o0);
                break;
            case '*'.charCodeAt(0):
                sb.append(0o1);
                break;
            case '>'.charCodeAt(0):
                sb.append(0o2);
                break;
            case ' '.charCodeAt(0):
                sb.append(0o3);
                break;
            default:
                if (c >= '0'.charCodeAt(0) && c <= '9'.charCodeAt(0)) {
                    sb.append(c - 48 + 4);
                }
                else if (c >= 'A'.charCodeAt(0) && c <= 'Z'.charCodeAt(0)) {
                    sb.append(c - 65 + 14);
                }
                else {
                    HighLevelEncoder.illegalCharacter(StringUtils.getCharAt(c));
                }
                break;
        }
        return 1;
    }
    handleEOD(context, buffer) {
        context.updateSymbolInfo();
        const available = context.getSymbolInfo().getDataCapacity() - context.getCodewordCount();
        const count = buffer.length();
        context.pos -= count;
        if (context.getRemainingCharacters() > 1 ||
            available > 1 ||
            context.getRemainingCharacters() !== available) {
            context.writeCodeword(X12_UNLATCH);
        }
        if (context.getNewEncoding() < 0) {
            context.signalEncoderChange(ASCII_ENCODATION);
        }
    }
}