@zxing/library
Version:
TypeScript port of ZXing multi-format 1D/2D barcode image processing library.
134 lines (133 loc) • 5.38 kB
JavaScript
import StringUtils from '../../common/StringUtils';
import StringBuilder from '../../util/StringBuilder';
import { EDIFACT_ENCODATION, ASCII_ENCODATION } from './constants';
import HighLevelEncoder from './HighLevelEncoder';
var EdifactEncoder = /** @class */ (function () {
function EdifactEncoder() {
}
EdifactEncoder.prototype.getEncodingMode = function () {
return EDIFACT_ENCODATION;
};
EdifactEncoder.prototype.encode = function (context) {
// step F
var buffer = new StringBuilder();
while (context.hasMoreCharacters()) {
var c = context.getCurrentChar();
this.encodeChar(c, buffer);
context.pos++;
var count = buffer.length();
if (count >= 4) {
context.writeCodewords(this.encodeToCodewords(buffer.toString()));
var test_1 = buffer.toString().substring(4);
buffer.setLengthToZero();
buffer.append(test_1);
// buffer.delete(0, 4);
// for (let i = 0; i < 4; i++) {
// buffer.deleteCharAt(i);
// }
var 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;
}
}
}
buffer.append(StringUtils.getCharAt(31)); // Unlatch
this.handleEOD(context, buffer);
};
/**
* Handle "end of data" situations
*
* @param context the encoder context
* @param buffer the buffer with the remaining encoded characters
*/
EdifactEncoder.prototype.handleEOD = function (context, buffer) {
try {
var count = buffer.length();
if (count === 0) {
return; // Already finished
}
if (count === 1) {
// Only an unlatch at the end
context.updateSymbolInfo();
var available = context.getSymbolInfo().getDataCapacity() -
context.getCodewordCount();
var remaining = context.getRemainingCharacters();
// The following two lines are a hack inspired by the 'fix' from https://sourceforge.net/p/barcode4j/svn/221/
if (remaining > available) {
context.updateSymbolInfo(context.getCodewordCount() + 1);
available =
context.getSymbolInfo().getDataCapacity() -
context.getCodewordCount();
}
if (remaining <= available && available <= 2) {
return; // No unlatch
}
}
if (count > 4) {
throw new Error('Count must not exceed 4');
}
var restChars = count - 1;
var encoded = this.encodeToCodewords(buffer.toString());
var endOfSymbolReached = !context.hasMoreCharacters();
var restInAscii = endOfSymbolReached && restChars <= 2;
if (restChars <= 2) {
context.updateSymbolInfo(context.getCodewordCount() + restChars);
var available = context.getSymbolInfo().getDataCapacity() -
context.getCodewordCount();
if (available >= 3) {
restInAscii = false;
context.updateSymbolInfo(context.getCodewordCount() + encoded.length);
// available = context.symbolInfo.dataCapacity - context.getCodewordCount();
}
}
if (restInAscii) {
context.resetSymbolInfo();
context.pos -= restChars;
}
else {
context.writeCodewords(encoded);
}
}
finally {
context.signalEncoderChange(ASCII_ENCODATION);
}
};
EdifactEncoder.prototype.encodeChar = function (c, sb) {
if (c >= ' '.charCodeAt(0) && c <= '?'.charCodeAt(0)) {
sb.append(c);
}
else if (c >= '@'.charCodeAt(0) && c <= '^'.charCodeAt(0)) {
sb.append(StringUtils.getCharAt(c - 64));
}
else {
HighLevelEncoder.illegalCharacter(StringUtils.getCharAt(c));
}
};
EdifactEncoder.prototype.encodeToCodewords = function (sb) {
var len = sb.length;
if (len === 0) {
throw new Error('StringBuilder must not be empty');
}
var c1 = sb.charAt(0).charCodeAt(0);
var c2 = len >= 2 ? sb.charAt(1).charCodeAt(0) : 0;
var c3 = len >= 3 ? sb.charAt(2).charCodeAt(0) : 0;
var c4 = len >= 4 ? sb.charAt(3).charCodeAt(0) : 0;
var v = (c1 << 18) + (c2 << 12) + (c3 << 6) + c4;
var cw1 = (v >> 16) & 255;
var cw2 = (v >> 8) & 255;
var cw3 = v & 255;
var res = new StringBuilder();
res.append(cw1);
if (len >= 2) {
res.append(cw2);
}
if (len >= 3) {
res.append(cw3);
}
return res.toString();
};
return EdifactEncoder;
}());
export { EdifactEncoder };