pdf-lib
Version:
Create and modify PDF files with JavaScript
144 lines • 7.91 kB
JavaScript
"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
var tslib_1 = require("tslib");
var PDFCrossRefSection_1 = tslib_1.__importDefault(require("../document/PDFCrossRefSection"));
var PDFHeader_1 = tslib_1.__importDefault(require("../document/PDFHeader"));
var PDFTrailer_1 = tslib_1.__importDefault(require("../document/PDFTrailer"));
var PDFTrailerDict_1 = tslib_1.__importDefault(require("../document/PDFTrailerDict"));
var PDFObjectStream_1 = tslib_1.__importDefault(require("../structures/PDFObjectStream"));
var CharCodes_1 = tslib_1.__importDefault(require("../syntax/CharCodes"));
var utils_1 = require("../../utils");
var PDFWriter = /** @class */ (function () {
function PDFWriter(context, objectsPerTick) {
var _this = this;
this.parsedObjects = 0;
this.shouldWaitForTick = function (n) {
_this.parsedObjects += n;
return _this.parsedObjects % _this.objectsPerTick === 0;
};
this.context = context;
this.objectsPerTick = objectsPerTick;
}
PDFWriter.prototype.serializeToBuffer = function () {
return tslib_1.__awaiter(this, void 0, void 0, function () {
var _a, size, header, indirectObjects, xref, trailerDict, trailer, offset, buffer, idx, len, _b, ref, object, objectNumber, generationNumber, n;
return tslib_1.__generator(this, function (_c) {
switch (_c.label) {
case 0: return [4 /*yield*/, this.computeBufferSize()];
case 1:
_a = _c.sent(), size = _a.size, header = _a.header, indirectObjects = _a.indirectObjects, xref = _a.xref, trailerDict = _a.trailerDict, trailer = _a.trailer;
offset = 0;
buffer = new Uint8Array(size);
offset += header.copyBytesInto(buffer, offset);
buffer[offset++] = CharCodes_1.default.Newline;
buffer[offset++] = CharCodes_1.default.Newline;
idx = 0, len = indirectObjects.length;
_c.label = 2;
case 2:
if (!(idx < len)) return [3 /*break*/, 5];
_b = indirectObjects[idx], ref = _b[0], object = _b[1];
objectNumber = String(ref.objectNumber);
offset += utils_1.copyStringIntoBuffer(objectNumber, buffer, offset);
buffer[offset++] = CharCodes_1.default.Space;
generationNumber = String(ref.generationNumber);
offset += 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;
n = object instanceof PDFObjectStream_1.default ? object.getObjectsCount() : 1;
if (!this.shouldWaitForTick(n)) return [3 /*break*/, 4];
return [4 /*yield*/, utils_1.waitForTick()];
case 3:
_c.sent();
_c.label = 4;
case 4:
idx++;
return [3 /*break*/, 2];
case 5:
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 [2 /*return*/, buffer];
}
});
});
};
PDFWriter.prototype.computeIndirectObjectSize = function (_a) {
var ref = _a[0], object = _a[1];
var refSize = ref.sizeInBytes() + 3; // 'R' -> 'obj\n'
var objectSize = object.sizeInBytes() + 9; // '\nendobj\n\n'
return refSize + objectSize;
};
PDFWriter.prototype.createTrailerDict = function () {
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,
});
};
PDFWriter.prototype.computeBufferSize = function () {
return tslib_1.__awaiter(this, void 0, void 0, function () {
var header, size, xref, indirectObjects, idx, len, indirectObject, ref, xrefOffset, trailerDict, trailer;
return tslib_1.__generator(this, function (_a) {
switch (_a.label) {
case 0:
header = PDFHeader_1.default.forVersion(1, 7);
size = header.sizeInBytes() + 2;
xref = PDFCrossRefSection_1.default.create();
indirectObjects = this.context.enumerateIndirectObjects();
idx = 0, len = indirectObjects.length;
_a.label = 1;
case 1:
if (!(idx < len)) return [3 /*break*/, 4];
indirectObject = indirectObjects[idx];
ref = indirectObject[0];
xref.addEntry(ref, size);
size += this.computeIndirectObjectSize(indirectObject);
if (!this.shouldWaitForTick(1)) return [3 /*break*/, 3];
return [4 /*yield*/, utils_1.waitForTick()];
case 2:
_a.sent();
_a.label = 3;
case 3:
idx++;
return [3 /*break*/, 1];
case 4:
xrefOffset = size;
size += xref.sizeInBytes() + 1; // '\n'
trailerDict = PDFTrailerDict_1.default.of(this.createTrailerDict());
size += trailerDict.sizeInBytes() + 2; // '\n\n'
trailer = PDFTrailer_1.default.forLastCrossRefSectionOffset(xrefOffset);
size += trailer.sizeInBytes();
return [2 /*return*/, { size: size, header: header, indirectObjects: indirectObjects, xref: xref, trailerDict: trailerDict, trailer: trailer }];
}
});
});
};
PDFWriter.forContext = function (context, objectsPerTick) {
return new PDFWriter(context, objectsPerTick);
};
return PDFWriter;
}());
exports.default = PDFWriter;
//# sourceMappingURL=PDFWriter.js.map