pdf-lib
Version:
Create and modify PDF files with JavaScript
91 lines • 4.63 kB
JavaScript
;
Object.defineProperty(exports, "__esModule", { value: true });
var tslib_1 = require("tslib");
var errors_1 = require("../errors");
var PDFNumber_1 = tslib_1.__importDefault(require("../objects/PDFNumber"));
var PDFRawStream_1 = tslib_1.__importDefault(require("../objects/PDFRawStream"));
var PDFStream_1 = tslib_1.__importDefault(require("../objects/PDFStream"));
var decode_1 = require("../streams/decode");
var PDFContentStream_1 = tslib_1.__importDefault(require("../structures/PDFContentStream"));
var CharCodes_1 = tslib_1.__importDefault(require("../syntax/CharCodes"));
var utils_1 = require("../../utils");
var fullPageBoundingBox = function (page) {
var mediaBox = page.MediaBox();
var width = mediaBox.lookup(2, PDFNumber_1.default).asNumber() -
mediaBox.lookup(0, PDFNumber_1.default).asNumber();
var height = mediaBox.lookup(3, PDFNumber_1.default).asNumber() -
mediaBox.lookup(1, PDFNumber_1.default).asNumber();
return { left: 0, bottom: 0, right: width, top: height };
};
// Returns the identity matrix, modified to position the content of the given
// bounding box at (0, 0).
var boundingBoxAdjustedMatrix = function (bb) { return [1, 0, 0, 1, -bb.left, -bb.bottom]; };
var PDFPageEmbedder = /** @class */ (function () {
function PDFPageEmbedder(page, boundingBox, transformationMatrix) {
this.page = page;
var bb = boundingBox !== null && boundingBox !== void 0 ? boundingBox : fullPageBoundingBox(page);
this.width = bb.right - bb.left;
this.height = bb.top - bb.bottom;
this.boundingBox = bb;
this.transformationMatrix = transformationMatrix !== null && transformationMatrix !== void 0 ? transformationMatrix : boundingBoxAdjustedMatrix(bb);
}
PDFPageEmbedder.for = function (page, boundingBox, transformationMatrix) {
return tslib_1.__awaiter(this, void 0, void 0, function () {
return tslib_1.__generator(this, function (_a) {
return [2 /*return*/, new PDFPageEmbedder(page, boundingBox, transformationMatrix)];
});
});
};
PDFPageEmbedder.prototype.embedIntoContext = function (context, ref) {
return tslib_1.__awaiter(this, void 0, void 0, function () {
var _a, Contents, Resources, decodedContents, _b, left, bottom, right, top, xObject;
return tslib_1.__generator(this, function (_c) {
_a = this.page.normalizedEntries(), Contents = _a.Contents, Resources = _a.Resources;
if (!Contents)
throw new errors_1.MissingPageContentsEmbeddingError();
decodedContents = this.decodeContents(Contents);
_b = this.boundingBox, left = _b.left, bottom = _b.bottom, right = _b.right, top = _b.top;
xObject = context.flateStream(decodedContents, {
Type: 'XObject',
Subtype: 'Form',
FormType: 1,
BBox: [left, bottom, right, top],
Matrix: this.transformationMatrix,
Resources: Resources,
});
if (ref) {
context.assign(ref, xObject);
return [2 /*return*/, ref];
}
else {
return [2 /*return*/, context.register(xObject)];
}
return [2 /*return*/];
});
});
};
// `contents` is an array of streams which are merged to include them in the XObject.
// This methods extracts each stream and joins them with a newline character.
PDFPageEmbedder.prototype.decodeContents = function (contents) {
var newline = Uint8Array.of(CharCodes_1.default.Newline);
var decodedContents = [];
for (var idx = 0, len = contents.size(); idx < len; idx++) {
var stream = contents.lookup(idx, PDFStream_1.default);
var content = void 0;
if (stream instanceof PDFRawStream_1.default) {
content = decode_1.decodePDFRawStream(stream).decode();
}
else if (stream instanceof PDFContentStream_1.default) {
content = stream.getUnencodedContents();
}
else {
throw new errors_1.UnrecognizedStreamTypeError(stream);
}
decodedContents.push(content, newline);
}
return utils_1.mergeIntoTypedArray.apply(void 0, decodedContents);
};
return PDFPageEmbedder;
}());
exports.default = PDFPageEmbedder;
//# sourceMappingURL=PDFPageEmbedder.js.map