import { ASCII_ENCODATION, BASE256_ENCODATION, C40_ENCODATION, EDIFACT_ENCODATION, LATCH_TO_ANSIX12, LATCH_TO_BASE256, LATCH_TO_C40, LATCH_TO_EDIFACT, LATCH_TO_TEXT, TEXT_ENCODATION, UPPER_SHIFT, X12_ENCODATION, } from './constants';
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// tslint:disable-next-line:no-circular-imports
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import HighLevelEncoder from './HighLevelEncoder';
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export class ASCIIEncoder {
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getEncodingMode() {
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return ASCII_ENCODATION;
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}
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encode(context) {
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// step B
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const n = HighLevelEncoder.determineConsecutiveDigitCount(context.getMessage(), context.pos);
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if (n >= 2) {
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context.writeCodeword(this.encodeASCIIDigits(context.getMessage().charCodeAt(context.pos), context.getMessage().charCodeAt(context.pos + 1)));
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context.pos += 2;
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}
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else {
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const c = context.getCurrentChar();
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const newMode = HighLevelEncoder.lookAheadTest(context.getMessage(), context.pos, this.getEncodingMode());
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if (newMode !== this.getEncodingMode()) {
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switch (newMode) {
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case BASE256_ENCODATION:
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context.writeCodeword(LATCH_TO_BASE256);
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context.signalEncoderChange(BASE256_ENCODATION);
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return;
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case C40_ENCODATION:
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context.writeCodeword(LATCH_TO_C40);
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context.signalEncoderChange(C40_ENCODATION);
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return;
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case X12_ENCODATION:
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context.writeCodeword(LATCH_TO_ANSIX12);
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context.signalEncoderChange(X12_ENCODATION);
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break;
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case TEXT_ENCODATION:
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context.writeCodeword(LATCH_TO_TEXT);
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context.signalEncoderChange(TEXT_ENCODATION);
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break;
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case EDIFACT_ENCODATION:
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context.writeCodeword(LATCH_TO_EDIFACT);
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context.signalEncoderChange(EDIFACT_ENCODATION);
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break;
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default:
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throw new Error('Illegal mode: ' + newMode);
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}
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}
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else if (HighLevelEncoder.isExtendedASCII(c)) {
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context.writeCodeword(UPPER_SHIFT);
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context.writeCodeword(c - 128 + 1);
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context.pos++;
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}
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else {
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context.writeCodeword(c + 1);
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context.pos++;
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}
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}
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}
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encodeASCIIDigits(digit1, digit2) {
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if (HighLevelEncoder.isDigit(digit1) && HighLevelEncoder.isDigit(digit2)) {
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const num = (digit1 - 48) * 10 + (digit2 - 48);
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return num + 130;
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}
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throw new Error('not digits: ' + digit1 + digit2);
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}
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}
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