@pdfme/pdf-lib/dist/cjs/src/core/writers/PDFWriter.js

Create and modify PDF files with JavaScript

"use strict";
var __importDefault = (this && this.__importDefault) || function (mod) {
    return (mod && mod.__esModule) ? mod : { "default": mod };
};
Object.defineProperty(exports, "__esModule", { value: true });
const PDFCrossRefSection_1 = __importDefault(require("../document/PDFCrossRefSection"));
const PDFHeader_1 = __importDefault(require("../document/PDFHeader"));
const PDFTrailer_1 = __importDefault(require("../document/PDFTrailer"));
const PDFTrailerDict_1 = __importDefault(require("../document/PDFTrailerDict"));
const PDFObjectStream_1 = __importDefault(require("../structures/PDFObjectStream"));
const CharCodes_1 = __importDefault(require("../syntax/CharCodes"));
const utils_1 = require("../../utils");
class PDFWriter {
    constructor(context, objectsPerTick) {
        Object.defineProperty(this, "context", {
            enumerable: true,
            configurable: true,
            writable: true,
            value: void 0
        });
        Object.defineProperty(this, "objectsPerTick", {
            enumerable: true,
            configurable: true,
            writable: true,
            value: void 0
        });
        Object.defineProperty(this, "parsedObjects", {
            enumerable: true,
            configurable: true,
            writable: true,
            value: 0
        });
        Object.defineProperty(this, "shouldWaitForTick", {
            enumerable: true,
            configurable: true,
            writable: true,
            value: (n) => {
                this.parsedObjects += n;
                return this.parsedObjects % this.objectsPerTick === 0;
            }
        });
        this.context = context;
        this.objectsPerTick = objectsPerTick;
    }
    async serializeToBuffer() {
        const { size, header, indirectObjects, xref, trailerDict, trailer } = await this.computeBufferSize();
        let offset = 0;
        const buffer = new Uint8Array(size);
        offset += header.copyBytesInto(buffer, offset);
        buffer[offset++] = CharCodes_1.default.Newline;
        buffer[offset++] = CharCodes_1.default.Newline;
        for (let idx = 0, len = indirectObjects.length; idx < len; idx++) {
            const [ref, object] = indirectObjects[idx];
            const objectNumber = String(ref.objectNumber);
            offset += (0, utils_1.copyStringIntoBuffer)(objectNumber, buffer, offset);
            buffer[offset++] = CharCodes_1.default.Space;
            const generationNumber = String(ref.generationNumber);
            offset += (0, utils_1.copyStringIntoBuffer)(generationNumber, buffer, offset);
            buffer[offset++] = CharCodes_1.default.Space;
            buffer[offset++] = CharCodes_1.default.o;
            buffer[offset++] = CharCodes_1.default.b;
            buffer[offset++] = CharCodes_1.default.j;
            buffer[offset++] = CharCodes_1.default.Newline;
            offset += object.copyBytesInto(buffer, offset);
            buffer[offset++] = CharCodes_1.default.Newline;
            buffer[offset++] = CharCodes_1.default.e;
            buffer[offset++] = CharCodes_1.default.n;
            buffer[offset++] = CharCodes_1.default.d;
            buffer[offset++] = CharCodes_1.default.o;
            buffer[offset++] = CharCodes_1.default.b;
            buffer[offset++] = CharCodes_1.default.j;
            buffer[offset++] = CharCodes_1.default.Newline;
            buffer[offset++] = CharCodes_1.default.Newline;
            const n = object instanceof PDFObjectStream_1.default ? object.getObjectsCount() : 1;
            if (this.shouldWaitForTick(n))
                await (0, utils_1.waitForTick)();
        }
        if (xref) {
            offset += xref.copyBytesInto(buffer, offset);
            buffer[offset++] = CharCodes_1.default.Newline;
        }
        if (trailerDict) {
            offset += trailerDict.copyBytesInto(buffer, offset);
            buffer[offset++] = CharCodes_1.default.Newline;
            buffer[offset++] = CharCodes_1.default.Newline;
        }
        offset += trailer.copyBytesInto(buffer, offset);
        return buffer;
    }
    computeIndirectObjectSize([ref, object]) {
        const refSize = ref.sizeInBytes() + 3; // 'R' -> 'obj\n'
        const objectSize = object.sizeInBytes() + 9; // '\nendobj\n\n'
        return refSize + objectSize;
    }
    createTrailerDict() {
        return this.context.obj({
            Size: this.context.largestObjectNumber + 1,
            Root: this.context.trailerInfo.Root,
            Encrypt: this.context.trailerInfo.Encrypt,
            Info: this.context.trailerInfo.Info,
            ID: this.context.trailerInfo.ID,
        });
    }
    async computeBufferSize() {
        const header = PDFHeader_1.default.forVersion(1, 7);
        let size = header.sizeInBytes() + 2;
        const xref = PDFCrossRefSection_1.default.create();
        const indirectObjects = this.context.enumerateIndirectObjects();
        for (let idx = 0, len = indirectObjects.length; idx < len; idx++) {
            const indirectObject = indirectObjects[idx];
            const [ref] = indirectObject;
            xref.addEntry(ref, size);
            size += this.computeIndirectObjectSize(indirectObject);
            if (this.shouldWaitForTick(1))
                await (0, utils_1.waitForTick)();
        }
        const xrefOffset = size;
        size += xref.sizeInBytes() + 1; // '\n'
        const trailerDict = PDFTrailerDict_1.default.of(this.createTrailerDict());
        size += trailerDict.sizeInBytes() + 2; // '\n\n'
        const trailer = PDFTrailer_1.default.forLastCrossRefSectionOffset(xrefOffset);
        size += trailer.sizeInBytes();
        return { size, header, indirectObjects, xref, trailerDict, trailer };
    }
}
Object.defineProperty(PDFWriter, "forContext", {
    enumerable: true,
    configurable: true,
    writable: true,
    value: (context, objectsPerTick) => new PDFWriter(context, objectsPerTick)
});
exports.default = PDFWriter;
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