import { decoderError } from "../../encoding/encodings";
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import { finished } from "../../encoding/finished";
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import { index, indexCodePointFor } 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 ShiftJISDecoder = /** @class */ (function () {
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function ShiftJISDecoder(options) {
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this.fatal = options.fatal;
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// Shift_JIS's decoder has an associated Shift_JIS lead (initially
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// 0x00).
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/** @type {number} */ this.Shift_JIS_lead = 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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ShiftJISDecoder.prototype.handler = function (stream, bite) {
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// 1. If byte is end-of-stream and Shift_JIS lead is not 0x00,
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// set Shift_JIS lead to 0x00 and return error.
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if (bite === end_of_stream && this.Shift_JIS_lead !== 0x00) {
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this.Shift_JIS_lead = 0x00;
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return decoderError(this.fatal);
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}
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// 2. If byte is end-of-stream and Shift_JIS lead is 0x00,
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// return finished.
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if (bite === end_of_stream && this.Shift_JIS_lead === 0x00)
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return finished;
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// 3. If Shift_JIS lead is not 0x00, let lead be Shift_JIS lead,
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// let pointer be null, set Shift_JIS lead to 0x00, and then run
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// these substeps:
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if (this.Shift_JIS_lead !== 0x00) {
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var lead = this.Shift_JIS_lead;
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var pointer = null;
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this.Shift_JIS_lead = 0x00;
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// 1. 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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// 2. Let lead offset be 0x81, if lead is less than 0xA0, and
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// 0xC1 otherwise.
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var lead_offset = (lead < 0xA0) ? 0x81 : 0xC1;
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// 3. If byte is in the range 0x40 to 0x7E, inclusive, or 0x80
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// to 0xFC, inclusive, set pointer to (lead − lead offset) ×
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// 188 + byte − offset.
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if (inRange(bite, 0x40, 0x7E) || inRange(bite, 0x80, 0xFC))
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pointer = (lead - lead_offset) * 188 + bite - offset;
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// 4. If pointer is in the range 8836 to 10715, inclusive,
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// return a code point whose value is 0xE000 − 8836 + pointer.
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if (inRange(pointer, 8836, 10715))
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return 0xE000 - 8836 + pointer;
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// 5. Let code point be null, if pointer is null, and the
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// index code point for pointer in index jis0208 otherwise.
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var code_point = (pointer === null) ? null :
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indexCodePointFor(pointer, index('jis0208'));
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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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// 4. If byte is an ASCII byte or 0x80, return a code point
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// whose value is byte.
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if (isASCIIByte(bite) || bite === 0x80)
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return bite;
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// 5. If byte is in the range 0xA1 to 0xDF, inclusive, return a
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// code point whose value is 0xFF61 − 0xA1 + byte.
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if (inRange(bite, 0xA1, 0xDF))
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return 0xFF61 - 0xA1 + bite;
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// 6. If byte is in the range 0x81 to 0x9F, inclusive, or 0xE0
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// to 0xFC, inclusive, set Shift_JIS lead to byte and return
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// continue.
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if (inRange(bite, 0x81, 0x9F) || inRange(bite, 0xE0, 0xFC)) {
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this.Shift_JIS_lead = bite;
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return null;
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}
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// 7. Return error.
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return decoderError(this.fatal);
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};
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return ShiftJISDecoder;
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}());
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export { ShiftJISDecoder };
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//# sourceMappingURL=ShiftJISDecoder.js.map
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