pdf-lib
Version:
Library for creating and modifying PDF files in JavaScript
31 lines (30 loc) • 1.44 kB
JavaScript
// tslint:disable-next-line:no-unused-variable
import { PDFIndirectReference } from '../pdf-objects';
import { arrayIndexOf, arrayToString, trimArrayAndRemoveComments } from '../../utils';
/**
* Accepts an array of bytes as input. Checks to see if the first characters in the
* trimmed input make up a PDF Indirect Reference.
*
* If so, returns a tuple containing (1) an object representing the parsed PDF
* Indirect Reference and (2) a subarray of the input with the characters making up
* the parsed indirect reference removed. The "onParseIndirectRef" parse handler
* will also be called with the PDFIndirectReference.
*
* If not, null is returned.
*/
var parseIndirectRef = function (input, _a) {
var onParseIndirectRef = (_a === void 0 ? {} : _a).onParseIndirectRef;
var trimmed = trimArrayAndRemoveComments(input);
var indirectRefRegex = /^(\d+)[\0\t\n\f\r ]*(\d+)[\0\t\n\f\r ]*R/;
// Check that initial characters make up an indirect reference
var rIdx = arrayIndexOf(trimmed, 'R');
var result = arrayToString(trimmed, 0, rIdx + 1).match(indirectRefRegex);
if (!result)
return undefined;
var fullMatch = result[0], objNum = result[1], genNum = result[2];
var ref = PDFIndirectReference.forNumbers(Number(objNum), Number(genNum));
if (onParseIndirectRef)
onParseIndirectRef(ref);
return [ref, trimmed.subarray(fullMatch.length)];
};
export default parseIndirectRef;