pdf-lib
Version:
Create and modify PDF files with JavaScript
113 lines • 6.83 kB
JavaScript
"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
var tslib_1 = require("tslib");
var PDFHeader_1 = tslib_1.__importDefault(require("../document/PDFHeader"));
var PDFTrailer_1 = tslib_1.__importDefault(require("../document/PDFTrailer"));
var PDFInvalidObject_1 = tslib_1.__importDefault(require("../objects/PDFInvalidObject"));
var PDFName_1 = tslib_1.__importDefault(require("../objects/PDFName"));
var PDFNumber_1 = tslib_1.__importDefault(require("../objects/PDFNumber"));
var PDFRef_1 = tslib_1.__importDefault(require("../objects/PDFRef"));
var PDFStream_1 = tslib_1.__importDefault(require("../objects/PDFStream"));
var PDFCrossRefStream_1 = tslib_1.__importDefault(require("../structures/PDFCrossRefStream"));
var PDFObjectStream_1 = tslib_1.__importDefault(require("../structures/PDFObjectStream"));
var PDFWriter_1 = tslib_1.__importDefault(require("./PDFWriter"));
var utils_1 = require("../../utils");
var PDFStreamWriter = /** @class */ (function (_super) {
tslib_1.__extends(PDFStreamWriter, _super);
function PDFStreamWriter(context, objectsPerTick, encodeStreams, objectsPerStream) {
var _this = _super.call(this, context, objectsPerTick) || this;
_this.encodeStreams = encodeStreams;
_this.objectsPerStream = objectsPerStream;
return _this;
}
PDFStreamWriter.prototype.computeBufferSize = function () {
return tslib_1.__awaiter(this, void 0, void 0, function () {
var objectNumber, header, size, xrefStream, uncompressedObjects, compressedObjects, objectStreamRefs, indirectObjects, idx, len, indirectObject, ref, object, shouldNotCompress, chunk, objectStreamRef, idx, len, chunk, ref, objectStream, xrefStreamRef, xrefOffset, trailer;
return tslib_1.__generator(this, function (_a) {
switch (_a.label) {
case 0:
objectNumber = this.context.largestObjectNumber + 1;
header = PDFHeader_1.default.forVersion(1, 7);
size = header.sizeInBytes() + 2;
xrefStream = PDFCrossRefStream_1.default.create(this.createTrailerDict(), this.encodeStreams);
uncompressedObjects = [];
compressedObjects = [];
objectStreamRefs = [];
indirectObjects = this.context.enumerateIndirectObjects();
idx = 0, len = indirectObjects.length;
_a.label = 1;
case 1:
if (!(idx < len)) return [3 /*break*/, 6];
indirectObject = indirectObjects[idx];
ref = indirectObject[0], object = indirectObject[1];
shouldNotCompress = ref === this.context.trailerInfo.Encrypt ||
object instanceof PDFStream_1.default ||
object instanceof PDFInvalidObject_1.default ||
ref.generationNumber !== 0;
if (!shouldNotCompress) return [3 /*break*/, 4];
uncompressedObjects.push(indirectObject);
xrefStream.addUncompressedEntry(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: return [3 /*break*/, 5];
case 4:
chunk = utils_1.last(compressedObjects);
objectStreamRef = utils_1.last(objectStreamRefs);
if (!chunk || chunk.length % this.objectsPerStream === 0) {
chunk = [];
compressedObjects.push(chunk);
objectStreamRef = PDFRef_1.default.of(objectNumber++);
objectStreamRefs.push(objectStreamRef);
}
xrefStream.addCompressedEntry(ref, objectStreamRef, chunk.length);
chunk.push(indirectObject);
_a.label = 5;
case 5:
idx++;
return [3 /*break*/, 1];
case 6:
idx = 0, len = compressedObjects.length;
_a.label = 7;
case 7:
if (!(idx < len)) return [3 /*break*/, 10];
chunk = compressedObjects[idx];
ref = objectStreamRefs[idx];
objectStream = PDFObjectStream_1.default.withContextAndObjects(this.context, chunk, this.encodeStreams);
xrefStream.addUncompressedEntry(ref, size);
size += this.computeIndirectObjectSize([ref, objectStream]);
uncompressedObjects.push([ref, objectStream]);
if (!this.shouldWaitForTick(chunk.length)) return [3 /*break*/, 9];
return [4 /*yield*/, utils_1.waitForTick()];
case 8:
_a.sent();
_a.label = 9;
case 9:
idx++;
return [3 /*break*/, 7];
case 10:
xrefStreamRef = PDFRef_1.default.of(objectNumber++);
xrefStream.dict.set(PDFName_1.default.of('Size'), PDFNumber_1.default.of(objectNumber));
xrefStream.addUncompressedEntry(xrefStreamRef, size);
xrefOffset = size;
size += this.computeIndirectObjectSize([xrefStreamRef, xrefStream]);
uncompressedObjects.push([xrefStreamRef, xrefStream]);
trailer = PDFTrailer_1.default.forLastCrossRefSectionOffset(xrefOffset);
size += trailer.sizeInBytes();
return [2 /*return*/, { size: size, header: header, indirectObjects: uncompressedObjects, trailer: trailer }];
}
});
});
};
PDFStreamWriter.forContext = function (context, objectsPerTick, encodeStreams, objectsPerStream) {
if (encodeStreams === void 0) { encodeStreams = true; }
if (objectsPerStream === void 0) { objectsPerStream = 50; }
return new PDFStreamWriter(context, objectsPerTick, encodeStreams, objectsPerStream);
};
return PDFStreamWriter;
}(PDFWriter_1.default));
exports.default = PDFStreamWriter;
//# sourceMappingURL=PDFStreamWriter.js.map