jtc-utils
Version:
Utilities for Japanese Traditional Companies
187 lines (186 loc) • 7.24 kB
JavaScript
import { PackedMap } from "../util/PackedMap.mjs";
import { IBMKanjiDecodeMap } from "./IBMKanjiDecodeMap.mjs";
import { IBMKanjiEncodeMap } from "./IBMKanjiEncodeMap.mjs";
class Cp939Charset {
get name() {
return "cp939";
}
createDecoder(options) {
return new Cp939Decoder(options);
}
createEncoder(options) {
return new Cp939Encoder(options);
}
isUnicode() {
return false;
}
isEbcdic() {
return true;
}
}
const EbcdicDecodeMap = Uint16Array.of(
// 0 1 2 3 4 5 6 7 8 9 A B C D E F
0x0000, 0x0001, 0x0002, 0x0003, 0x009c, 0x0009, 0x0086, 0x007f, 0x0097, 0x008d, 0x008e, 0x000b, 0x000c, 0x000d, 0xfffd, 0xfffd, // 0x
0x0010, 0x0011, 0x0012, 0x0013, 0x009d, 0x000a, 0x0008, 0x0087, 0x0018, 0x0019, 0x0092, 0x008f, 0x001c, 0x001d, 0x001e, 0x001f, // 1x
0x0080, 0x0081, 0x0082, 0x0083, 0x0084, 0x000a, 0x0017, 0x001b, 0x0088, 0x0089, 0x008a, 0x008b, 0x008c, 0x0005, 0x0006, 0x0007, // 2x
0x0090, 0x0091, 0x0016, 0x0093, 0x0094, 0x0095, 0x0096, 0x0004, 0x0098, 0x0099, 0x009a, 0x009b, 0x0014, 0x0015, 0x009e, 0x001a, // 3x
0x0020, 0xfffd, 0xff61, 0xff62, 0xff63, 0xff64, 0xff65, 0xff66, 0xff67, 0xff68, 0x00a2, 0x002e, 0x003c, 0x0028, 0x002b, 0x007c, // 4x
0x0026, 0xff69, 0xff6a, 0xff6b, 0xff6c, 0xff6d, 0xff6e, 0xff6f, 0xff70, 0xff71, 0x0021, 0x0024, 0x002a, 0x0029, 0x003b, 0x00ac, // 5x
0x002d, 0x002f, 0xff72, 0xff73, 0xff74, 0xff75, 0xff76, 0xff77, 0xff78, 0xff79, 0xfffd, 0x002c, 0x0025, 0x005f, 0x003e, 0x003f, // 6x
0xff7a, 0xff7b, 0xff7c, 0xff7d, 0xff7e, 0xff7f, 0xff80, 0xff81, 0xff82, 0x0060, 0x003a, 0x0023, 0x0040, 0x0027, 0x003d, 0x0022, // 7x
0xfffd, 0x0061, 0x0062, 0x0063, 0x0064, 0x0065, 0x0066, 0x0067, 0x0068, 0x0069, 0xff83, 0xff84, 0xff85, 0xff86, 0xff87, 0xff88, // 8x
0xfffd, 0x006a, 0x006b, 0x006c, 0x006d, 0x006e, 0x006f, 0x0070, 0x0071, 0x0072, 0xff89, 0xff8a, 0xff8b, 0xff8c, 0xff8d, 0xff8e, // 9x
0x203e, 0x007e, 0x0073, 0x0074, 0x0075, 0x0076, 0x0077, 0x0078, 0x0079, 0x007a, 0xff8f, 0xff90, 0xff91, 0x005b, 0xff92, 0xff93, // Ax
0x005e, 0x00a3, 0x00a5, 0xff94, 0xff95, 0xff96, 0xff97, 0xff98, 0xff99, 0xff9a, 0xff9b, 0xff9c, 0xff9d, 0x005d, 0xff9e, 0xff9f, // Bx
0x007b, 0x0041, 0x0042, 0x0043, 0x0044, 0x0045, 0x0046, 0x0047, 0x0048, 0x0049, 0xfffd, 0xfffd, 0xfffd, 0xfffd, 0xfffd, 0xfffd, // Cx
0x007d, 0x004a, 0x004b, 0x004c, 0x004d, 0x004e, 0x004f, 0x0050, 0x0051, 0x0052, 0xfffd, 0xfffd, 0xfffd, 0xfffd, 0xfffd, 0xfffd, // Dx
0x005c, 0xfffd, 0x0053, 0x0054, 0x0055, 0x0056, 0x0057, 0x0058, 0x0059, 0x005a, 0xfffd, 0xfffd, 0xfffd, 0xfffd, 0xfffd, 0xfffd, // Ex
0x0030, 0x0031, 0x0032, 0x0033, 0x0034, 0x0035, 0x0036, 0x0037, 0x0038, 0x0039, 0xfffd, 0xfffd, 0xfffd, 0xfffd, 0xfffd, 0x009f);
class Cp939Decoder {
fatal;
state;
constructor(options) {
this.fatal = options?.fatal ?? true;
IBMKanjiDecodeMap.initialize();
}
decode(input, options) {
let shift = options?.shift ?? false;
const array = new Array();
if (options?.stream && this.state) {
shift = this.state.shift;
array.push(this.state.buf);
this.state = undefined;
}
for (let i = 0; i < input.length; i++) {
let fail = false;
const n = input[i];
if (n === 0x0e) {
shift = true;
}
else if (n === 0x0f) {
shift = false;
}
else if (shift) {
if (i + 1 < input.length) {
i++;
const enc = IBMKanjiDecodeMap.get((n << 8) | input[i]);
if (enc != null) {
array.push(enc);
}
else {
fail = true;
}
}
else if (options?.stream) {
this.state = { shift, buf: n };
break;
}
else {
fail = true;
}
}
else {
const c = EbcdicDecodeMap[n];
if (c !== 0xfffd) {
array.push(c);
}
else {
fail = true;
}
}
if (fail) {
if (this.fatal) {
throw TypeError(`The input ${n.toString(16)} could not be encoded.`);
}
else {
array.push(0xfffd);
}
}
}
return String.fromCharCode(...array);
}
}
const EbcdicEncodeMap = new PackedMap((m) => {
const decoder = new Cp939Decoder({ fatal: false });
m.set(0x85, 0x15);
const buf = new Uint8Array(1);
for (let b = 0x00; b <= 0xff; b++) {
buf[0] = b;
const decoded = decoder.decode(buf);
if (decoded && decoded !== "\uFFFD") {
m.set(decoded.charCodeAt(0), b);
}
}
});
class Cp939Encoder {
fatal;
constructor(options) {
this.fatal = options?.fatal ?? true;
EbcdicEncodeMap.initialize();
IBMKanjiEncodeMap.initialize();
}
canEncode(str) {
for (let i = 0; i < str.length; i++) {
const cp = str.charCodeAt(i);
if (EbcdicEncodeMap.get(cp) != null) {
// EBCDIC
// no handle
}
else if (IBMKanjiEncodeMap.get(cp) != null) {
// no handle
}
else {
return false;
}
}
return true;
}
encode(str, options) {
const out = new Array();
const limit = options?.limit ?? Number.POSITIVE_INFINITY;
let shift = options?.shift ?? false;
let prev = 0;
for (let i = 0; i < str.length; i++) {
prev = out.length;
const cp = str.charCodeAt(i);
let enc;
if ((enc = EbcdicEncodeMap.get(cp)) != null) {
// EBCDIC
if (shift) {
out.push(0x0f);
shift = false;
}
out.push(enc);
}
else if ((enc = IBMKanjiEncodeMap.get(cp)) != null) {
if (!shift) {
out.push(0x0e);
shift = true;
}
out.push((enc >>> 8) & 0xff);
out.push(enc & 0xff);
}
else {
if (this.fatal) {
throw TypeError(`The code point ${cp.toString(16)} could not be encoded`);
}
else if (shift) {
out.push(0x42); // ？
out.push(0x6f);
}
else {
out.push(0x6f); // ?
}
}
if (out.length > limit) {
out.length = prev;
break;
}
}
if (shift && options?.shift !== true && out.length < limit) {
out.push(0x0f);
}
return Uint8Array.from(out);
}
}
export const cp939 = new Cp939Charset();