EUCKREncoder.js 1.6 KB

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  1. import { encoderError } from "../../encoding/encodings";
  2. import { finished } from "../../encoding/finished";
  3. import { index, indexPointerFor } from "../../encoding/indexes";
  4. import { end_of_stream, isASCIICodePoint } from "../../encoding/terminology";
  5. /**
  6. * @constructor
  7. * @implements {Encoder}
  8. * @param {{fatal: boolean}} options
  9. */
  10. export class EUCKREncoder {
  11. constructor(options) {
  12. this.fatal = options.fatal;
  13. }
  14. /**
  15. * @param {Stream} stream Input stream.
  16. * @param {number} code_point Next code point read from the stream.
  17. * @return {(number|!Array.<number>)} Byte(s) to emit.
  18. */
  19. handler(stream, code_point) {
  20. // 1. If code point is end-of-stream, return finished.
  21. if (code_point === end_of_stream)
  22. return finished;
  23. // 2. If code point is an ASCII code point, return a byte whose
  24. // value is code point.
  25. if (isASCIICodePoint(code_point))
  26. return code_point;
  27. // 3. Let pointer be the index pointer for code point in index
  28. // euc-kr.
  29. const pointer = indexPointerFor(code_point, index('euc-kr'));
  30. // 4. If pointer is null, return error with code point.
  31. if (pointer === null)
  32. return encoderError(code_point);
  33. // 5. Let lead be Math.floor(pointer / 190) + 0x81.
  34. const lead = Math.floor(pointer / 190) + 0x81;
  35. // 6. Let trail be pointer % 190 + 0x41.
  36. const trail = (pointer % 190) + 0x41;
  37. // 7. Return two bytes whose values are lead and trail.
  38. return [lead, trail];
  39. }
  40. }
  41. //# sourceMappingURL=EUCKREncoder.js.map