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- import { encoderError } from "../../encoding/encodings";
- import { finished } from "../../encoding/finished";
- import { indexBig5PointerFor } from "../../encoding/indexes";
- import { end_of_stream, isASCIICodePoint } from "../../encoding/terminology";
- /**
- * @constructor
- * @implements {Encoder}
- * @param {{fatal: boolean}} options
- */
- export class Big5Encoder {
- constructor(options) {
- this.fatal = options.fatal;
- }
- /**
- * @param {Stream} stream Input stream.
- * @param {number} code_point Next code point read from the stream.
- * @return {(number|!Array.<number>)} Byte(s) to emit.
- */
- handler(stream, code_point) {
- // 1. If code point is end-of-stream, return finished.
- if (code_point === end_of_stream)
- return finished;
- // 2. If code point is an ASCII code point, return a byte whose
- // value is code point.
- if (isASCIICodePoint(code_point))
- return code_point;
- // 3. Let pointer be the index Big5 pointer for code point.
- const pointer = indexBig5PointerFor(code_point);
- // 4. If pointer is null, return error with code point.
- if (pointer === null)
- return encoderError(code_point);
- // 5. Let lead be Math.floor(pointer / 157) + 0x81.
- const lead = Math.floor(pointer / 157) + 0x81;
- // 6. If lead is less than 0xA1, return error with code point.
- if (lead < 0xA1)
- return encoderError(code_point);
- // 7. Let trail be pointer % 157.
- const trail = pointer % 157;
- // 8. Let offset be 0x40 if trail is less than 0x3F and 0x62
- // otherwise.
- const offset = trail < 0x3F ? 0x40 : 0x62;
- // Return two bytes whose values are lead and trail + offset.
- return [lead, trail + offset];
- }
- }
- //# sourceMappingURL=Big5Encoder.js.map
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