"use strict"; Object.defineProperty(exports, "__esModule", { value: true }); exports.BinaryParser = void 0; var assert = require("assert"); var enums_1 = require("../enums"); var buffer_1 = require("buffer/"); /** * BinaryParser is used to compute fields and values from a HexString */ var BinaryParser = /** @class */ (function () { /** * Initialize bytes to a hex string * * @param hexBytes a hex string */ function BinaryParser(hexBytes) { this.bytes = buffer_1.Buffer.from(hexBytes, 'hex'); } /** * Peek the first byte of the BinaryParser * * @returns The first byte of the BinaryParser */ BinaryParser.prototype.peek = function () { assert.ok(this.bytes.byteLength !== 0); return this.bytes[0]; }; /** * Consume the first n bytes of the BinaryParser * * @param n the number of bytes to skip */ BinaryParser.prototype.skip = function (n) { assert.ok(n <= this.bytes.byteLength); this.bytes = this.bytes.slice(n); }; /** * read the first n bytes from the BinaryParser * * @param n The number of bytes to read * @return The bytes */ BinaryParser.prototype.read = function (n) { assert.ok(n <= this.bytes.byteLength); var slice = this.bytes.slice(0, n); this.skip(n); return slice; }; /** * Read an integer of given size * * @param n The number of bytes to read * @return The number represented by those bytes */ BinaryParser.prototype.readUIntN = function (n) { assert.ok(0 < n && n <= 4, 'invalid n'); return this.read(n).reduce(function (a, b) { return (a << 8) | b; }) >>> 0; }; BinaryParser.prototype.readUInt8 = function () { return this.readUIntN(1); }; BinaryParser.prototype.readUInt16 = function () { return this.readUIntN(2); }; BinaryParser.prototype.readUInt32 = function () { return this.readUIntN(4); }; BinaryParser.prototype.size = function () { return this.bytes.byteLength; }; BinaryParser.prototype.end = function (customEnd) { var length = this.bytes.byteLength; return length === 0 || (customEnd !== undefined && length <= customEnd); }; /** * Reads variable length encoded bytes * * @return The variable length bytes */ BinaryParser.prototype.readVariableLength = function () { return this.read(this.readVariableLengthLength()); }; /** * Reads the length of the variable length encoded bytes * * @return The length of the variable length encoded bytes */ BinaryParser.prototype.readVariableLengthLength = function () { var b1 = this.readUInt8(); if (b1 <= 192) { return b1; } else if (b1 <= 240) { var b2 = this.readUInt8(); return 193 + (b1 - 193) * 256 + b2; } else if (b1 <= 254) { var b2 = this.readUInt8(); var b3 = this.readUInt8(); return 12481 + (b1 - 241) * 65536 + b2 * 256 + b3; } throw new Error('Invalid variable length indicator'); }; /** * Reads the field ordinal from the BinaryParser * * @return Field ordinal */ BinaryParser.prototype.readFieldOrdinal = function () { var type = this.readUInt8(); var nth = type & 15; type >>= 4; if (type === 0) { type = this.readUInt8(); if (type === 0 || type < 16) { throw new Error('Cannot read FieldOrdinal, type_code out of range'); } } if (nth === 0) { nth = this.readUInt8(); if (nth === 0 || nth < 16) { throw new Error('Cannot read FieldOrdinal, field_code out of range'); } } return (type << 16) | nth; }; /** * Read the field from the BinaryParser * * @return The field represented by the bytes at the head of the BinaryParser */ BinaryParser.prototype.readField = function () { return enums_1.Field.fromString(this.readFieldOrdinal().toString()); }; /** * Read a given type from the BinaryParser * * @param type The type that you want to read from the BinaryParser * @return The instance of that type read from the BinaryParser */ BinaryParser.prototype.readType = function (type) { return type.fromParser(this); }; /** * Get the type associated with a given field * * @param field The field that you wan to get the type of * @return The type associated with the given field */ BinaryParser.prototype.typeForField = function (field) { return field.associatedType; }; /** * Read value of the type specified by field from the BinaryParser * * @param field The field that you want to get the associated value for * @return The value associated with the given field */ BinaryParser.prototype.readFieldValue = function (field) { var type = this.typeForField(field); if (!type) { throw new Error("unsupported: (".concat(field.name, ", ").concat(field.type.name, ")")); } var sizeHint = field.isVariableLengthEncoded ? this.readVariableLengthLength() : undefined; var value = type.fromParser(this, sizeHint); if (value === undefined) { throw new Error("fromParser for (".concat(field.name, ", ").concat(field.type.name, ") -> undefined ")); } return value; }; /** * Get the next field and value from the BinaryParser * * @return The field and value */ BinaryParser.prototype.readFieldAndValue = function () { var field = this.readField(); return [field, this.readFieldValue(field)]; }; return BinaryParser; }()); exports.BinaryParser = BinaryParser; //# sourceMappingURL=binary-parser.js.map