@syncfusion/ej2-pdf
Version:
Feature-rich JavaScript PDF library with built-in support for loading and manipulating PDF document.
612 lines (611 loc) • 18.8 kB
JavaScript
import { _escapePdfName } from './../utils';
import { _PdfColorSpace } from '../enumerator';
/**
* Low level PDF content writer that emits PDF operators and operands into
* a content stream. Provides helpers for graphics state, paths, text, color,
* and resource execution.
*
* @private
*/
var _PdfStreamWriter = /** @class */ (function () {
/**
* Creates a new stream writer bound to the given content stream.
*
* @param {_PdfContentStream} stream The target content stream to write to.
*
* @private
*/
function _PdfStreamWriter(stream) {
/**
* Newline delimiter used when writing PDF operators.
*
* @private
*/
this._newLine = '\r\n';
/**
* Single whitespace used when separating PDF operator tokens.
*
* @private
*/
this._whiteSpace = ' ';
this._stream = stream;
}
/**
* Writes a raw PDF operator string followed by EOL.
*
* @param {string} value The operator string to write.
* @returns {void} nothing.
*
* @private
*/
_PdfStreamWriter.prototype._writeOperator = function (value) {
this._stream.write(value);
this._stream.write(this._newLine);
};
/**
* Saves the current graphics state `q`.
*
* @private
* @returns {void} nothing.
*/
_PdfStreamWriter.prototype._saveGraphicsState = function () {
this._writeOperator('q');
};
/**
* Restores the previous graphics state `Q`.
*
* @private
* @returns {void} nothing.
*/
_PdfStreamWriter.prototype._restoreGraphicsState = function () {
this._writeOperator('Q');
};
/**
* Writes a PDF comment line when non-empty.
*
* @param {string} comment The comment text (no EOL needed).
* @returns {void} nothing.
*
* @private
*/
_PdfStreamWriter.prototype._writeComment = function (comment) {
if (comment && comment.length > 0) {
this._writeOperator('% ' + comment);
}
};
/**
* Sets the extended graphics state.
*
* @param {_PdfName} value The ExtGState resource name.
* @returns {void} nothing.
*
* @private
*/
_PdfStreamWriter.prototype._setGraphicsState = function (value) {
this._stream.write("/" + _escapePdfName(value.name) + " ");
this._writeOperator('gs');
};
/**
* Concatenates matrix with the current transformation matrix `cm`.
*
* @param {_PdfTransformationMatrix} matrix The transformation to apply.
* @returns {void} nothing.
*
* @private
*/
_PdfStreamWriter.prototype._modifyCtm = function (matrix) {
this._stream.write(matrix._toString() + " ");
this._writeOperator('cm');
};
/**
* Sets the text matrix and text line matrix `Tm`.
*
* @param {_PdfTransformationMatrix} matrix The text matrix to set.
* @returns {void} nothing.
*
* @private
*/
_PdfStreamWriter.prototype._modifyTM = function (matrix) {
this._stream.write(matrix._toString() + " ");
this._writeOperator('Tm');
};
_PdfStreamWriter.prototype._setColorSpace = function (value, arg2, arg3) {
if (typeof value === 'string' && typeof arg2 === 'boolean') {
this._stream.write("/" + value + " ");
this._writeOperator(arg2 ? 'CS' : 'cs');
}
else if (Array.isArray(value) && typeof arg2 === 'number' && typeof arg3 === 'boolean') {
var colorSpaceName = void 0;
switch (arg2) {
case _PdfColorSpace.rgb:
colorSpaceName = 'DeviceRGB';
break;
case _PdfColorSpace.cmyk:
colorSpaceName = 'DeviceCMYK';
break;
case _PdfColorSpace.grayScale:
colorSpaceName = 'DeviceGray';
break;
default:
colorSpaceName = 'DeviceRGB';
break;
}
this._stream.write("/" + colorSpaceName + " ");
this._writeOperator(arg3 ? 'CS' : 'cs');
this._setColor(value, arg3);
}
};
/**
* Sets the current color for DeviceRGB using 0..255 components.
*
* @param {number[]} color The RGB array `[r,g,b]` (0..255).
* @param {boolean} forStroking True for stroking color (`RG`), false for non-stroking (`rg`).
* @returns {void} nothing.
*
* @private
*/
_PdfStreamWriter.prototype._setColor = function (color, forStroking) {
this._stream.write((color[0] / 255).toFixed(3) + " " + (color[1] / 255).toFixed(3) + " " + (color[2] / 255).toFixed(3) + " ");
this._writeOperator(forStroking ? 'RG' : 'rg');
};
/**
* Appends a rectangle to the current path, using the current CTM.
*
* @param {number} x Left.
* @param {number} y Top.
* @param {number} width Width.
* @param {number} height Height.
* @returns {void} nothing.
*
* @private
*/
_PdfStreamWriter.prototype._appendRectangle = function (x, y, width, height) {
this._writePoint(x, y);
this._writePoint(width, height);
this._writeOperator('re');
};
/**
* Writes a point as two operands, auto flipping Y to PDF coordinates.
*
* @param {number} x X coordinate.
* @param {number} y Y coordinate.
* @returns {void} nothing.
*
* @private
*/
_PdfStreamWriter.prototype._writePoint = function (x, y) {
this._stream.write(x.toFixed(3) + " " + (-y).toFixed(3) + " ");
};
/**
* Applies the current path as a clipping path and ends path.
*
* @param {boolean} isEvenOdd True for evenodd rule, false for nonzero.
* @returns {void} nothing.
*
* @private
*/
_PdfStreamWriter.prototype._clipPath = function (isEvenOdd) {
this._stream.write((isEvenOdd ? 'W*' : 'W') + " n" + this._newLine);
};
/**
* Fills the current path and ends the path.
*
* @param {boolean} isEvenOdd True for evenodd rule, false for nonzero.
* @returns {void} nothing.
*
* @private
*/
_PdfStreamWriter.prototype._fillPath = function (isEvenOdd) {
this._writeOperator(isEvenOdd ? 'f*' : 'f');
};
/**
* Closes the current subpath then fill.
*
* @param {boolean} isEvenOdd True for evenodd rule, false for nonzero.
* @returns {void} nothing.
*
* @private
*/
_PdfStreamWriter.prototype._closeFillPath = function (isEvenOdd) {
this._writeOperator('h');
this._fillPath(isEvenOdd);
};
/**
* Strokes the current path `S` and ends the path.
*
* @private
* @returns {void} nothing.
*/
_PdfStreamWriter.prototype._strokePath = function () {
this._writeOperator('S');
};
/**
* Closes and strokes the current path `s` and ends the path.
*
* @private
* @returns {void} nothing.
*/
_PdfStreamWriter.prototype._closeStrokePath = function () {
this._writeOperator('s');
};
/**
* Fills and strokes the current path and ends the path.
*
* @param {boolean} isEvenOdd True for evenodd rule, false for nonzero.
* @returns {void} nothing.
*
* @private
*/
_PdfStreamWriter.prototype._fillStrokePath = function (isEvenOdd) {
this._writeOperator(isEvenOdd ? 'B*' : 'B');
};
/**
* Closes, fills, and strokes the current path and ends the path.
*
* @param {boolean} isEvenOdd True for evenodd rule, false for nonzero.
* @returns {void} nothing.
*
* @private
*/
_PdfStreamWriter.prototype._closeFillStrokePath = function (isEvenOdd) {
this._writeOperator(isEvenOdd ? 'b*' : 'b');
};
/**
* Ends the current path without filling or stroking `n`.
*
* @private
* @returns {void} nothing.
*/
_PdfStreamWriter.prototype._endPath = function () {
this._writeOperator('n');
};
/**
* Sets the current font and size.
*
* @param {string} name The font resource name.
* @param {number} size The font size in user units.
* @returns {void} nothing.
*
* @private
*/
_PdfStreamWriter.prototype._setFont = function (name, size) {
this._stream.write("/" + name + " " + size.toFixed(3) + " ");
this._writeOperator('Tf');
};
/**
* Sets horizontal text scaling in percent.
*
* @param {number} textScaling The scaling factor in percent.
* @returns {void} nothing.
*
* @private
*/
_PdfStreamWriter.prototype._setTextScaling = function (textScaling) {
this._stream.write(textScaling.toFixed(3) + " ");
this._writeOperator('Tz');
};
/**
* Closes the current subpath (`h`). Usually used before fill/stroke.
*
* @private
* @returns {void} nothing.
*/
_PdfStreamWriter.prototype._closePath = function () {
this._writeOperator('h');
};
_PdfStreamWriter.prototype._startNextLine = function (x, y) {
if (typeof x === 'undefined') {
this._writeOperator('T*');
}
else {
this._writePoint(x, y);
this._writeOperator('Td');
}
};
/**
* Sets text leading `TL`, the vertical distance between baselines.
*
* @param {number} leading The leading in user units.
* @returns {void} nothing.
*
* @private
*/
_PdfStreamWriter.prototype._setLeading = function (leading) {
this._write(leading.toFixed(3) + " ");
this._write(this._whiteSpace);
this._writeOperator('TL');
};
/**
* Shows text using the literal string form. The text is escaped as needed.
*
* @param {string} text The literal text content.
* @returns {void} nothing.
*
* @private
*/
_PdfStreamWriter.prototype._showText = function (text) {
this._writeText(text);
this._writeOperator('Tj');
};
/**
* Writes a raw string + CRLF, then as an operator. Internal helper.
*
* @param {string} string The string to write.
* @returns {void} nothing.
*
* @private
*/
_PdfStreamWriter.prototype._write = function (string) {
var builder = '';
builder += string;
builder += '\r\n';
this._writeOperator(builder);
};
/**
* Writes a literal string operand with necessary escaping and parentheses wrapping.
*
* @param {string} text The unescaped text content.
* @returns {void} nothing.
*
* @private
*/
_PdfStreamWriter.prototype._writeText = function (text) {
var result = '';
var data = this._escapeSymbols(text);
for (var i = 0; i < data.length; i++) {
result += String.fromCharCode(data[i]); // eslint-disable-line
}
result = '(' + result + ')';
this._stream.write(result);
};
/**
* Begins a text object.
*
* @private
* @returns {void} nothing.
*/
_PdfStreamWriter.prototype._beginText = function () {
this._writeOperator('BT');
};
/**
* Ends a text object.
*
* @private
* @returns {void} nothing.
*/
_PdfStreamWriter.prototype._endText = function () {
this._writeOperator('ET');
};
/**
* Begins a new subpath at the specified point.
*
* @param {number} x X coordinate.
* @param {number} y Y coordinate.
* @returns {void} nothing.
*
* @private
*/
_PdfStreamWriter.prototype._beginPath = function (x, y) {
this._writePoint(x, y);
this._writeOperator('m');
};
/**
* Appends a line segment to the specified point.
*
* @param {number} x X coordinate.
* @param {number} y Y coordinate.
* @returns {void} nothing.
*
* @private
*/
_PdfStreamWriter.prototype._appendLineSegment = function (x, y) {
this._writePoint(x, y);
this._writeOperator('l');
};
/**
* Appends a cubic Bezier curve segment with two control points and an endpoint.
*
* @param {number} x1 First control point X.
* @param {number} y1 First control point Y.
* @param {number} x2 Second control point X.
* @param {number} y2 Second control point Y.
* @param {number} x3 End point X.
* @param {number} y3 End point Y.
* @returns {void} nothing.
*
* @private
*/
_PdfStreamWriter.prototype._appendBezierSegment = function (x1, y1, x2, y2, x3, y3) {
this._writePoint(x1, y1);
this._writePoint(x2, y2);
this._writePoint(x3, y3);
this._writeOperator('c');
};
/**
* Sets the text rendering mode, combining fill/stroke/clip flags.
*
* @private
* @param {number} renderingMode The rendering mode integer.
* @returns {void} nothing.
*/
_PdfStreamWriter.prototype._setTextRenderingMode = function (renderingMode) {
this._stream.write(renderingMode.toString() + " ");
this._writeOperator('Tr');
};
/**
* Sets character spacing in user units.
*
* @private
* @param {number} charSpacing The character spacing.
* @returns {void} nothing.
*/
_PdfStreamWriter.prototype._setCharacterSpacing = function (charSpacing) {
this._stream.write(charSpacing.toFixed(3) + " ");
this._writeOperator('Tc');
};
/**
* Sets word spacing in user units.
*
* @private
* @param {number} wordSpacing The word spacing.
* @returns {void} nothing.
*/
_PdfStreamWriter.prototype._setWordSpacing = function (wordSpacing) {
this._stream.write(wordSpacing.toFixed(3) + " ");
this._writeOperator('Tw');
};
_PdfStreamWriter.prototype._showNextLineText = function (text, unicode) {
if (unicode !== null && typeof unicode !== 'undefined' && unicode) {
this._writeText(text);
this._writeOperator('\'');
}
else {
this._stream.write(text);
this._writeOperator('\'');
}
};
/**
* Sets the line dash pattern. Pattern elements are lengths in user units.
*
* @private
* @param {number[]} pattern The dash/gap pattern array.
* @param {number} patternOffset The dash phase offset.
* @returns {void} nothing.
*/
_PdfStreamWriter.prototype._setLineDashPattern = function (pattern, patternOffset) {
var tempPattern = '[';
if (pattern.length >= 1) {
for (var index = 0; index < pattern.length; index++) {
if (index === pattern.length - 1) {
tempPattern += pattern[index].toString(); // eslint-disable-line
}
else {
tempPattern += pattern[index].toString() + ' '; // eslint-disable-line
}
}
}
tempPattern += '] ';
tempPattern += patternOffset.toString();
tempPattern += ' d';
this._writeOperator(tempPattern);
};
/**
* Sets the miter limit.
*
* @private
* @param {number} miterLimit The miter limit value.
* @returns {void} nothing.
*/
_PdfStreamWriter.prototype._setMiterLimit = function (miterLimit) {
this._stream.write(miterLimit.toFixed(3) + " ");
this._writeOperator('M');
};
/**
* Sets the line width (`w`).
*
* @private
* @param {number} width The stroke width in user units.
* @returns {void} nothing.
*/
_PdfStreamWriter.prototype._setLineWidth = function (width) {
this._stream.write(width.toFixed(3) + " ");
this._writeOperator('w');
};
/**
* Sets the line cap style.
*
* @private
* @param {number} lineCapStyle The line cap style (0=butt, 1=round, 2=square).
* @returns {void} nothing.
*/
_PdfStreamWriter.prototype._setLineCap = function (lineCapStyle) {
this._stream.write(lineCapStyle + " ");
this._writeOperator('J');
};
/**
* Sets the line join style.
*
* @private
* @param {number} lineJoinStyle The join style (0=miter, 1=round, 2=bevel).
* @returns {void} nothing.
*/
_PdfStreamWriter.prototype._setLineJoin = function (lineJoinStyle) {
this._stream.write(lineJoinStyle + " ");
this._writeOperator('j');
};
/**
* Executes a named XObject or other resource.
*
* @private
* @param {_PdfName} name The resource name to execute.
* @returns {void} nothing.
*/
_PdfStreamWriter.prototype._executeObject = function (name) {
this._stream.write("/" + name.name + " ");
this._writeOperator('Do');
};
/**
* Begins a markedcontent sequence.
*
* @private
* @param {string} name The markedcontent tag name.
* @returns {void} nothing.
*/
_PdfStreamWriter.prototype._beginMarkupSequence = function (name) {
this._stream.write("/" + name + " ");
this._writeOperator('BMC');
};
/**
* Ends a markedcontent sequence.
*
* @private
* @returns {void} nothing.
*/
_PdfStreamWriter.prototype._endMarkupSequence = function () {
this._writeOperator('EMC');
};
/**
* Clears the underlying content stream buffer.
*
* @private
* @returns {void} nothing.
*/
_PdfStreamWriter.prototype._clear = function () {
this._stream._bytes = [];
};
/**
* Escapes special characters for PDF literal strings.
*
* @param {string} value The unescaped text.
* @returns {number[]} The escaped byte values.
*
* @private
*/
_PdfStreamWriter.prototype._escapeSymbols = function (value) {
var data = [];
for (var i = 0; i < value.length; i++) {
var currentData = value.charCodeAt(i);
switch (currentData) {
case 40:
case 41:
data.push(92);
data.push(currentData);
break;
case 13:
data.push(92);
data.push(114);
break;
case 92:
data.push(92);
data.push(currentData);
break;
default:
data.push(currentData);
break;
}
}
return data;
};
return _PdfStreamWriter;
}());
export { _PdfStreamWriter };