import { decoderError } from "../../encoding/encodings";
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import { finished } from "../../encoding/finished";
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import { index, indexCodePointFor, indexGB18030RangesCodePointFor } from "../../encoding/indexes";
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import { end_of_stream, isASCIIByte } from "../../encoding/terminology";
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import { inRange } from "../../encoding/utilities";
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/**
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* @constructor
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* @implements {Decoder}
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* @param {{fatal: boolean}} options
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*/
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var GB18030Decoder = /** @class */ (function () {
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function GB18030Decoder(options) {
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this.fatal = options.fatal;
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// gb18030's decoder has an associated gb18030 first, gb18030
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// second, and gb18030 third (all initially 0x00).
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/** @type {number} */ this.gb18030_first = 0x00,
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/** @type {number} */ this.gb18030_second = 0x00,
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/** @type {number} */ this.gb18030_third = 0x00;
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}
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/**
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* @param {Stream} stream The stream of bytes being decoded.
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* @param {number} bite The next byte read from the stream.
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* @return {?(number|!Array.<number>)} The next code point(s)
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* decoded, or null if not enough data exists in the input
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* stream to decode a complete code point.
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*/
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GB18030Decoder.prototype.handler = function (stream, bite) {
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// 1. If byte is end-of-stream and gb18030 first, gb18030
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// second, and gb18030 third are 0x00, return finished.
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if (bite === end_of_stream && this.gb18030_first === 0x00 &&
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this.gb18030_second === 0x00 && this.gb18030_third === 0x00) {
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return finished;
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}
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// 2. If byte is end-of-stream, and gb18030 first, gb18030
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// second, or gb18030 third is not 0x00, set gb18030 first,
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// gb18030 second, and gb18030 third to 0x00, and return error.
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if (bite === end_of_stream &&
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(this.gb18030_first !== 0x00 || this.gb18030_second !== 0x00 ||
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this.gb18030_third !== 0x00)) {
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this.gb18030_first = 0x00;
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this.gb18030_second = 0x00;
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this.gb18030_third = 0x00;
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decoderError(this.fatal);
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}
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var code_point;
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// 3. If gb18030 third is not 0x00, run these substeps:
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if (this.gb18030_third !== 0x00) {
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// 1. Let code point be null.
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code_point = null;
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// 2. If byte is in the range 0x30 to 0x39, inclusive, set
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// code point to the index gb18030 ranges code point for
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// (((gb18030 first − 0x81) × 10 + gb18030 second − 0x30) ×
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// 126 + gb18030 third − 0x81) × 10 + byte − 0x30.
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if (inRange(bite, 0x30, 0x39)) {
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code_point = indexGB18030RangesCodePointFor((((this.gb18030_first - 0x81) * 10 + this.gb18030_second - 0x30) * 126 +
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this.gb18030_third - 0x81) * 10 + bite - 0x30);
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}
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// 3. Let buffer be a byte sequence consisting of gb18030
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// second, gb18030 third, and byte, in order.
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var buffer = [this.gb18030_second, this.gb18030_third, bite];
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// 4. Set gb18030 first, gb18030 second, and gb18030 third to
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// 0x00.
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this.gb18030_first = 0x00;
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this.gb18030_second = 0x00;
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this.gb18030_third = 0x00;
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// 5. If code point is null, prepend buffer to stream and
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// return error.
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if (code_point === null) {
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stream.prepend(buffer);
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return decoderError(this.fatal);
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}
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// 6. Return a code point whose value is code point.
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return code_point;
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}
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// 4. If gb18030 second is not 0x00, run these substeps:
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if (this.gb18030_second !== 0x00) {
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// 1. If byte is in the range 0x81 to 0xFE, inclusive, set
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// gb18030 third to byte and return continue.
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if (inRange(bite, 0x81, 0xFE)) {
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this.gb18030_third = bite;
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return null;
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}
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// 2. Prepend gb18030 second followed by byte to stream, set
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// gb18030 first and gb18030 second to 0x00, and return error.
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stream.prepend([this.gb18030_second, bite]);
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this.gb18030_first = 0x00;
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this.gb18030_second = 0x00;
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return decoderError(this.fatal);
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}
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// 5. If gb18030 first is not 0x00, run these substeps:
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if (this.gb18030_first !== 0x00) {
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// 1. If byte is in the range 0x30 to 0x39, inclusive, set
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// gb18030 second to byte and return continue.
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if (inRange(bite, 0x30, 0x39)) {
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this.gb18030_second = bite;
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return null;
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}
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// 2. Let lead be gb18030 first, let pointer be null, and set
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// gb18030 first to 0x00.
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var lead = this.gb18030_first;
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var pointer = null;
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this.gb18030_first = 0x00;
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// 3. Let offset be 0x40 if byte is less than 0x7F and 0x41
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// otherwise.
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var offset = bite < 0x7F ? 0x40 : 0x41;
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// 4. If byte is in the range 0x40 to 0x7E, inclusive, or 0x80
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// to 0xFE, inclusive, set pointer to (lead − 0x81) × 190 +
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// (byte − offset).
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if (inRange(bite, 0x40, 0x7E) || inRange(bite, 0x80, 0xFE))
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pointer = (lead - 0x81) * 190 + (bite - offset);
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// 5. Let code point be null if pointer is null and the index
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// code point for pointer in index gb18030 otherwise.
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code_point = pointer === null ? null :
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indexCodePointFor(pointer, index('gb18030'));
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// 6. If code point is null and byte is an ASCII byte, prepend
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// byte to stream.
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if (code_point === null && isASCIIByte(bite))
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stream.prepend(bite);
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// 7. If code point is null, return error.
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if (code_point === null)
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return decoderError(this.fatal);
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// 8. Return a code point whose value is code point.
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return code_point;
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}
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// 6. If byte is an ASCII byte, return a code point whose value
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// is byte.
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if (isASCIIByte(bite))
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return bite;
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// 7. If byte is 0x80, return code point U+20AC.
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if (bite === 0x80)
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return 0x20AC;
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// 8. If byte is in the range 0x81 to 0xFE, inclusive, set
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// gb18030 first to byte and return continue.
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if (inRange(bite, 0x81, 0xFE)) {
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this.gb18030_first = bite;
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return null;
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}
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// 9. Return error.
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return decoderError(this.fatal);
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};
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return GB18030Decoder;
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}());
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export { GB18030Decoder };
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//# sourceMappingURL=GB18030Decoder.js.map
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