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/* eslint-disable @typescript-eslint/ban-ts-comment */
import * as pvtsutils from "pvtsutils";
import * as pvutils from "pvutils";
import { HexBlockJson, HexBlockParams, HexBlock } from "../HexBlock";
import { EMPTY_BUFFER, EMPTY_VIEW } from "./constants";
import { LocalBaseBlock, LocalBaseBlockJson } from "./LocalBaseBlock";
import { checkBufferParams } from "./utils";
export interface ILocalIdentificationBlock {
tagClass: number;
tagNumber: number;
isConstructed: boolean;
}
export interface LocalIdentificationBlockParams {
idBlock?: Partial<ILocalIdentificationBlock> & HexBlockParams;
}
export interface LocalIdentificationBlockJson extends HexBlockJson, LocalBaseBlockJson, ILocalIdentificationBlock { }
export class LocalIdentificationBlock extends HexBlock(LocalBaseBlock) implements ILocalIdentificationBlock {
public static override NAME = "identificationBlock";
public tagClass: number;
public tagNumber: number;
public isConstructed: boolean;
constructor({
idBlock = {},
}: LocalIdentificationBlockParams = {}) {
super();
if (idBlock) {
//#region Properties from hexBlock class
this.isHexOnly = idBlock.isHexOnly ?? false;
this.valueHexView = idBlock.valueHex ? pvtsutils.BufferSourceConverter.toUint8Array(idBlock.valueHex) : EMPTY_VIEW;
//#endregion
this.tagClass = idBlock.tagClass ?? -1;
this.tagNumber = idBlock.tagNumber ?? -1;
this.isConstructed = idBlock.isConstructed ?? false;
} else {
this.tagClass = -1;
this.tagNumber = -1;
this.isConstructed = false;
}
}
public override toBER(sizeOnly = false): ArrayBuffer {
let firstOctet = 0;
switch (this.tagClass) {
case 1:
firstOctet |= 0x00; // UNIVERSAL
break;
case 2:
firstOctet |= 0x40; // APPLICATION
break;
case 3:
firstOctet |= 0x80; // CONTEXT-SPECIFIC
break;
case 4:
firstOctet |= 0xC0; // PRIVATE
break;
default:
this.error = "Unknown tag class";
return EMPTY_BUFFER;
}
if (this.isConstructed)
firstOctet |= 0x20;
if (this.tagNumber < 31 && !this.isHexOnly) {
const retView = new Uint8Array(1);
if (!sizeOnly) {
let number = this.tagNumber;
number &= 0x1F;
firstOctet |= number;
retView[0] = firstOctet;
}
return retView.buffer;
}
if (!this.isHexOnly) {
const encodedBuf = pvutils.utilToBase(this.tagNumber, 7);
const encodedView = new Uint8Array(encodedBuf);
const size = encodedBuf.byteLength;
const retView = new Uint8Array(size + 1);
retView[0] = (firstOctet | 0x1F);
if (!sizeOnly) {
for (let i = 0; i < (size - 1); i++)
retView[i + 1] = encodedView[i] | 0x80;
retView[size] = encodedView[size - 1];
}
return retView.buffer;
}
const retView = new Uint8Array(this.valueHexView.byteLength + 1);
retView[0] = (firstOctet | 0x1F);
if (!sizeOnly) {
const curView = this.valueHexView;
for (let i = 0; i < (curView.length - 1); i++)
retView[i + 1] = curView[i] | 0x80;
retView[this.valueHexView.byteLength] = curView[curView.length - 1];
}
return retView.buffer;
}
public override fromBER(inputBuffer: ArrayBuffer | Uint8Array, inputOffset: number, inputLength: number): number {
const inputView = pvtsutils.BufferSourceConverter.toUint8Array(inputBuffer);
// Basic check for parameters
if (!checkBufferParams(this, inputView, inputOffset, inputLength)) {
return -1;
}
// Getting Uint8Array from ArrayBuffer
const intBuffer = inputView.subarray(inputOffset, inputOffset + inputLength);
// Initial checks
if (intBuffer.length === 0) {
this.error = "Zero buffer length";
return -1;
}
//#region Find tag class
const tagClassMask = intBuffer[0] & 0xC0;
switch (tagClassMask) {
case 0x00:
this.tagClass = (1); // UNIVERSAL
break;
case 0x40:
this.tagClass = (2); // APPLICATION
break;
case 0x80:
this.tagClass = (3); // CONTEXT-SPECIFIC
break;
case 0xC0:
this.tagClass = (4); // PRIVATE
break;
default:
this.error = "Unknown tag class";
return -1;
}
//#endregion
// Find it's constructed or not
this.isConstructed = (intBuffer[0] & 0x20) === 0x20;
// Find tag number
this.isHexOnly = false;
const tagNumberMask = intBuffer[0] & 0x1F;
if (tagNumberMask !== 0x1F) {
// Simple case (tag number < 31)
this.tagNumber = (tagNumberMask);
this.blockLength = 1;
} else {
// Tag number bigger or equal to 31
let count = 1;
let intTagNumberBuffer = this.valueHexView = new Uint8Array(255);
let tagNumberBufferMaxLength = 255;
while (intBuffer[count] & 0x80) {
intTagNumberBuffer[count - 1] = intBuffer[count] & 0x7F;
count++;
if (count >= intBuffer.length) {
this.error = "End of input reached before message was fully decoded";
return -1;
}
// In case if tag number length is greater than 255 bytes (rare but possible case)
if (count === tagNumberBufferMaxLength) {
tagNumberBufferMaxLength += 255;
const tempBufferView = new Uint8Array(tagNumberBufferMaxLength);
for (let i = 0; i < intTagNumberBuffer.length; i++)
tempBufferView[i] = intTagNumberBuffer[i];
intTagNumberBuffer = this.valueHexView = new Uint8Array(tagNumberBufferMaxLength);
}
}
this.blockLength = (count + 1);
intTagNumberBuffer[count - 1] = intBuffer[count] & 0x7F; // Write last byte to buffer
//#region Cut buffer
const tempBufferView = new Uint8Array(count);
for (let i = 0; i < count; i++)
tempBufferView[i] = intTagNumberBuffer[i];
intTagNumberBuffer = this.valueHexView = new Uint8Array(count);
intTagNumberBuffer.set(tempBufferView);
//#endregion
//#region Try to convert long tag number to short form
if (this.blockLength <= 9)
this.tagNumber = pvutils.utilFromBase(intTagNumberBuffer, 7);
else {
this.isHexOnly = true;
this.warnings.push("Tag too long, represented as hex-coded");
}
//#endregion
}
//#endregion
//#endregion
//#region Check if constructed encoding was using for primitive type
if (((this.tagClass === 1)) &&
(this.isConstructed)) {
switch (this.tagNumber) {
case 1: // Boolean
case 2: // REAL
case 5: // Null
case 6: // OBJECT IDENTIFIER
case 9: // REAL
case 13: // RELATIVE OBJECT IDENTIFIER
case 14: // Time
case 23:
case 24:
case 31:
case 32:
case 33:
case 34:
this.error = "Constructed encoding used for primitive type";
return -1;
default:
}
}
//#endregion
return (inputOffset + this.blockLength); // Return current offset in input buffer
}
public override toJSON(): LocalIdentificationBlockJson {
return {
...super.toJSON(),
tagClass: this.tagClass,
tagNumber: this.tagNumber,
isConstructed: this.isConstructed,
};
}
}
export interface LocalIdentificationBlock {
/**
* @deprecated since version 3.0.0
*/
// @ts-ignore
valueBeforeDecode: ArrayBuffer;
/**
* Binary data in ArrayBuffer representation
*
* @deprecated since version 3.0.0
*/
// @ts-ignore
valueHex: ArrayBuffer;
}