123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138
import { Buffer } from "./deps.ts";
import { PrependBOM, StripBOM } from "./bom_handling.ts";
// All codecs and aliases are kept here, keyed by encoding name/alias.import * as encodings from "./encodings/mod.ts";
// Characters emitted in case of error.const defaultCharUnicode = '�';const defaultCharSingleByte = '?';
export function encode(str: string, encoding: string, options?: {  addBOM?: boolean;}) {  str = "" + (str || ""); // Ensure string.
  const encoder = getEncoder(encoding, options);
  const res = encoder.write(str);  const trail = encoder.end();    return (trail && trail.length > 0) ? Buffer.concat([res, trail]) : res;}
export function decode(buf: Buffer, encoding: string, options?: {  stripBOM?: boolean | (() => void);}): string {  if (typeof buf === 'string') {    buf = Buffer.from("" + (buf || ""), "binary"); // Ensure buffer.  }
  const decoder = getDecoder(encoding, options);
  const res = decoder.write(buf);  const trail = decoder.end();
  return trail ? (res + trail) : res;}
export function encodingExists(encoding: string) {  try {    getCodec(encoding);    return true;  } catch (_e) {    return false;  }}
export const toEncoding = encode;export const fromEncoding = decode;
// deno-lint-ignore no-explicit-anyconst _codecDataCache: {[key: string]: any} = {};
export function getCodec(encoding: string) {  // Canonicalize encoding name: strip all non-alphanumeric chars and appended year.  let enc = _canonicalizeEncoding(encoding);
  // Traverse iconv.encodings to find actual codec.  // deno-lint-ignore no-explicit-any  const codecOptions: any = { };  while (true) {    let codec = _codecDataCache[enc];    if (codec) {      return codec;    }
    // deno-lint-ignore no-explicit-any    const codecDef = (encodings as any)[enc];
    switch (typeof codecDef) {      case "string": // Direct alias to other encoding.        enc = codecDef;        break;
      case "object": // Alias with options. Can be layered.        for (const key in codecDef) {          codecOptions[key] = codecDef[key];        }
        if (!codecOptions.encodingName) {          codecOptions.encodingName = enc;        }                enc = codecDef.type;        break;
      case "function": // Codec itself.        if (!codecOptions.encodingName) {          codecOptions.encodingName = enc;        }
        // The codec function must load all tables and return object with .encoder and .decoder methods.        // It'll be called only once (for each different options object).        codec = new codecDef(codecOptions, {          defaultCharUnicode,          defaultCharSingleByte,        });
        _codecDataCache[codecOptions.encodingName] = codec; // Save it to be reused later.        return codec;
      default:        throw new Error("Encoding not recognized: '" + encoding + "' (searched as: '"+enc+"')");    }  }}
function _canonicalizeEncoding(encoding: string) {  // Canonicalize encoding name: strip all non-alphanumeric chars and appended year.  return (''+encoding).toLowerCase().replace(/:\d{4}$|[^0-9a-z]/g, "");}
export function getEncoder(encoding: string, options?: {  addBOM?: boolean;}) {  const codec = getCodec(encoding);  let encoder = new codec.encoder(options, codec);
  if (codec.bomAware && options && options.addBOM) {    encoder = new PrependBOM(encoder, options);  }  return encoder;}
export function getDecoder(encoding: string, options?: {  stripBOM?: boolean | (() => void);}) {  const codec = getCodec(encoding);  let decoder = new codec.decoder(options, codec);
  if (codec.bomAware && !(options && options.stripBOM === false)) {    decoder = new StripBOM(decoder, options);  }    return decoder;}