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/// import
import { Buffer } from "node:buffer";


/// export
export class Name {  decodeBytes = 0;  encodeBytes = 0;
  decode(buf, offset?) {    if (!offset)      offset = 0;
    const list = [];    let consumedBytes = 0;    let jumped = false;    let oldOffset = offset;    let totalLength = 0;
    while(true) {      if (offset >= buf.length)        throw new Error("Cannot decode name (buffer overflow)");
      const len = buf[offset++];      consumedBytes += jumped ? 0 : 1;
      if (len === 0) {        break;      } else if ((len & 0xc0) === 0) {        if (offset + len > buf.length)          throw new Error("Cannot decode name (buffer overflow)");
        totalLength += len + 1;
        if (totalLength > 254)          throw new Error("Cannot decode name (name too long)");
        // @ts-ignore | TS2345 [ERROR]: Argument of type "any" is not assignable to parameter of type "never".        list.push(buf.toString("utf-8", offset, offset + len));        offset += len;        consumedBytes += jumped ? 0 : len;      } else if ((len & 0xc0) === 0xc0) {        if (offset + 1 > buf.length)          throw new Error("Cannot decode name (buffer overflow)");
        const jumpOffset = buf.readUInt16BE(offset - 1) - 0xc000;
        if (jumpOffset >= oldOffset) {          // Allow only pointers to prior data. RFC 1035, section 4.1.4 states:          // "[...] an entire domain name or a list of labels at the end of a domain name          // is replaced with a pointer to a prior occurance (sic) of the same name."          throw new Error("Cannot decode name (bad pointer)");        }
        offset = jumpOffset;        oldOffset = jumpOffset;        consumedBytes += jumped ? 0 : 1;        jumped = true;      } else {        throw new Error("Cannot decode name (bad label)");      }    }
    this.decodeBytes = consumedBytes;
    return list.length === 0 ?      "." :      list.join(".");  }
  encode(str, buf?, offset?) {    if (!buf)      buf = Buffer.alloc(this.encodingLength(str));
    if (!offset)      offset = 0;
    const oldOffset = offset;
    // strip leading and trailing .    const n = str.replace(/^\.|\.$/gm, "");    if (n.length) {      const list = n.split(".");
      for (let i = 0; i < list.length; i++) {        const len = buf.write(list[i], offset + 1);
        buf[offset] = len;        offset += len + 1;      }    }
    buf[offset++] = 0;    this.encodeBytes = offset - oldOffset;
    return buf;  }
  encodingLength(n) {    if (n === "." || n === "..")      return 1;
    return Buffer.byteLength(n.replace(/^\.|\.$/gm, "")) + 2;  }}