/* -*- Mode: Java; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set shiftwidth=2 tabstop=2 autoindent cindent expandtab: */
'use strict';
var PartialEvaluator = (function PartialEvaluatorClosure() {
function PartialEvaluator(xref, handler, uniquePrefix) {
this.state = new EvalState();
this.stateStack = [];
this.xref = xref;
this.handler = handler;
this.uniquePrefix = uniquePrefix;
this.objIdCounter = 0;
}
var OP_MAP = {
// Graphics state
w: 'setLineWidth',
J: 'setLineCap',
j: 'setLineJoin',
M: 'setMiterLimit',
d: 'setDash',
ri: 'setRenderingIntent',
i: 'setFlatness',
gs: 'setGState',
q: 'save',
Q: 'restore',
cm: 'transform',
// Path
m: 'moveTo',
l: 'lineTo',
c: 'curveTo',
v: 'curveTo2',
y: 'curveTo3',
h: 'closePath',
re: 'rectangle',
S: 'stroke',
s: 'closeStroke',
f: 'fill',
F: 'fill',
'f*': 'eoFill',
B: 'fillStroke',
'B*': 'eoFillStroke',
b: 'closeFillStroke',
'b*': 'closeEOFillStroke',
n: 'endPath',
// Clipping
W: 'clip',
'W*': 'eoClip',
// Text
BT: 'beginText',
ET: 'endText',
Tc: 'setCharSpacing',
Tw: 'setWordSpacing',
Tz: 'setHScale',
TL: 'setLeading',
Tf: 'setFont',
Tr: 'setTextRenderingMode',
Ts: 'setTextRise',
Td: 'moveText',
TD: 'setLeadingMoveText',
Tm: 'setTextMatrix',
'T*': 'nextLine',
Tj: 'showText',
TJ: 'showSpacedText',
"'": 'nextLineShowText',
'"': 'nextLineSetSpacingShowText',
// Type3 fonts
d0: 'setCharWidth',
d1: 'setCharWidthAndBounds',
// Color
CS: 'setStrokeColorSpace',
cs: 'setFillColorSpace',
SC: 'setStrokeColor',
SCN: 'setStrokeColorN',
sc: 'setFillColor',
scn: 'setFillColorN',
G: 'setStrokeGray',
g: 'setFillGray',
RG: 'setStrokeRGBColor',
rg: 'setFillRGBColor',
K: 'setStrokeCMYKColor',
k: 'setFillCMYKColor',
// Shading
sh: 'shadingFill',
// Images
BI: 'beginInlineImage',
ID: 'beginImageData',
EI: 'endInlineImage',
// XObjects
Do: 'paintXObject',
// Marked content
MP: 'markPoint',
DP: 'markPointProps',
BMC: 'beginMarkedContent',
BDC: 'beginMarkedContentProps',
EMC: 'endMarkedContent',
// Compatibility
BX: 'beginCompat',
EX: 'endCompat'
};
PartialEvaluator.prototype = {
getIRQueue: function partialEvaluatorGetIRQueue(stream, resources,
queue, dependency) {
var self = this;
var xref = this.xref;
var handler = this.handler;
var uniquePrefix = this.uniquePrefix || '';
function insertDependency(depList) {
fnArray.push('dependency');
argsArray.push(depList);
for (var i = 0, ii = depList.length; i < ii; i++) {
var dep = depList[i];
if (dependency.indexOf(dep) == -1) {
dependency.push(depList[i]);
}
}
}
function handleSetFont(fontName, fontRef) {
var loadedName = null;
var fontRes = resources.get('Font');
// TODO: TOASK: Is it possible to get here? If so, what does
// args[0].name should be like???
assert(fontRes, 'fontRes not available');
fontRes = xref.fetchIfRef(fontRes);
fontRef = fontRef || fontRes.get(fontName);
var font = xref.fetchIfRef(fontRef);
assertWellFormed(isDict(font));
if (!font.translated) {
font.translated = self.translateFont(font, xref, resources,
dependency);
if (font.translated) {
// keep track of each font we translated so the caller can
// load them asynchronously before calling display on a page
loadedName = 'font_' + uniquePrefix + (++self.objIdCounter);
font.translated.properties.loadedName = loadedName;
font.loadedName = loadedName;
var translated = font.translated;
// Convert the file to an ArrayBuffer which will be turned back into
// a Stream in the main thread.
if (translated.file)
translated.file = translated.file.getBytes();
handler.send('obj', [
loadedName,
'Font',
translated.name,
translated.file,
translated.properties
]);
}
}
loadedName = loadedName || font.loadedName;
// Ensure the font is ready before the font is set
// and later on used for drawing.
// TODO: This should get insert to the IRQueue only once per
// page.
insertDependency([loadedName]);
return loadedName;
}
function buildPaintImageXObject(image, inline) {
var dict = image.dict;
var w = dict.get('Width', 'W');
var h = dict.get('Height', 'H');
var imageMask = dict.get('ImageMask', 'IM') || false;
if (imageMask) {
// This depends on a tmpCanvas beeing filled with the
// current fillStyle, such that processing the pixel
// data can't be done here. Instead of creating a
// complete PDFImage, only read the information needed
// for later.
var width = dict.get('Width', 'W');
var height = dict.get('Height', 'H');
var bitStrideLength = (width + 7) >> 3;
var imgArray = image.getBytes(bitStrideLength * height);
var decode = dict.get('Decode', 'D');
var inverseDecode = !!decode && decode[0] > 0;
fn = 'paintImageMaskXObject';
args = [imgArray, inverseDecode, width, height];
return;
}
// If there is no imageMask, create the PDFImage and a lot
// of image processing can be done here.
var objId = 'img_' + uniquePrefix + (++self.objIdCounter);
insertDependency([objId]);
args = [objId, w, h];
var softMask = dict.get('SMask', 'IM') || false;
if (!softMask && image instanceof JpegStream &&
image.isNativelySupported(xref, resources)) {
// These JPEGs don't need any more processing so we can just send it.
fn = 'paintJpegXObject';
handler.send('obj', [objId, 'JpegStream', image.getIR()]);
return;
}
fn = 'paintImageXObject';
PDFImage.buildImage(function(imageObj) {
var drawWidth = imageObj.drawWidth;
var drawHeight = imageObj.drawHeight;
var imgData = {
width: drawWidth,
height: drawHeight,
data: new Uint8Array(drawWidth * drawHeight * 4)
};
var pixels = imgData.data;
imageObj.fillRgbaBuffer(pixels, drawWidth, drawHeight);
handler.send('obj', [objId, 'Image', imgData]);
}, handler, xref, resources, image, inline);
}
if (!queue.argsArray) {
queue.argsArray = [];
}
if (!queue.fnArray) {
queue.fnArray = [];
}
var fnArray = queue.fnArray, argsArray = queue.argsArray;
var dependencyArray = dependency || [];
resources = xref.fetchIfRef(resources) || new Dict();
var xobjs = xref.fetchIfRef(resources.get('XObject')) || new Dict();
var patterns = xref.fetchIfRef(resources.get('Pattern')) || new Dict();
var parser = new Parser(new Lexer(stream), false);
var res = resources;
var args = [], obj;
var getObjBt = function getObjBt() {
parser = this.oldParser;
return { name: 'BT' };
};
var TILING_PATTERN = 1, SHADING_PATTERN = 2;
while (!isEOF(obj = parser.getObj())) {
if (isCmd(obj)) {
var cmd = obj.cmd;
var fn = OP_MAP[cmd];
if (!fn) {
// invalid content command, trying to recover
if (cmd.substr(-2) == 'BT') {
fn = OP_MAP[cmd.substr(0, cmd.length - 2)];
// feeding 'BT' on next interation
parser = {
getObj: getObjBt,
oldParser: parser
};
}
}
assertWellFormed(fn, 'Unknown command "' + cmd + '"');
// TODO figure out how to type-check vararg functions
if ((cmd == 'SCN' || cmd == 'scn') && !args[args.length - 1].code) {
// Use the IR version for setStroke/FillColorN.
fn += '_IR';
// compile tiling patterns
var patternName = args[args.length - 1];
// SCN/scn applies patterns along with normal colors
if (isName(patternName)) {
var pattern = xref.fetchIfRef(patterns.get(patternName.name));
if (pattern) {
var dict = isStream(pattern) ? pattern.dict : pattern;
var typeNum = dict.get('PatternType');
if (typeNum == TILING_PATTERN) {
// Create an IR of the pattern code.
var depIdx = dependencyArray.length;
var queueObj = {};
var codeIR = this.getIRQueue(pattern, dict.get('Resources') ||
resources, queueObj, dependencyArray);
// Add the dependencies that are required to execute the
// codeIR.
insertDependency(dependencyArray.slice(depIdx));
args = TilingPattern.getIR(codeIR, dict, args);
}
else if (typeNum == SHADING_PATTERN) {
var shading = xref.fetchIfRef(dict.get('Shading'));
var matrix = dict.get('Matrix');
var pattern = Pattern.parseShading(shading, matrix, xref, res,
null /*ctx*/);
args = pattern.getIR();
} else {
error('Unkown PatternType ' + typeNum);
}
}
}
} else if (cmd == 'Do' && !args[0].code) {
// eagerly compile XForm objects
var name = args[0].name;
var xobj = xobjs.get(name);
if (xobj) {
xobj = xref.fetchIfRef(xobj);
assertWellFormed(isStream(xobj), 'XObject should be a stream');
var type = xobj.dict.get('Subtype');
assertWellFormed(
isName(type),
'XObject should have a Name subtype'
);
if ('Form' == type.name) {
var matrix = xobj.dict.get('Matrix');
var bbox = xobj.dict.get('BBox');
fnArray.push('paintFormXObjectBegin');
argsArray.push([matrix, bbox]);
// This adds the IRQueue of the xObj to the current queue.
var depIdx = dependencyArray.length;
this.getIRQueue(xobj, xobj.dict.get('Resources') || resources,
queue, dependencyArray);
// Add the dependencies that are required to execute the
// codeIR.
insertDependency(dependencyArray.slice(depIdx));
fn = 'paintFormXObjectEnd';
args = [];
} else if ('Image' == type.name) {
buildPaintImageXObject(xobj, false);
} else {
error('Unhandled XObject subtype ' + type.name);
}
}
} else if (cmd == 'Tf') { // eagerly collect all fonts
args[0] = handleSetFont(args[0].name);
} else if (cmd == 'EI') {
buildPaintImageXObject(args[0], true);
}
switch (fn) {
// Parse the ColorSpace data to a raw format.
case 'setFillColorSpace':
case 'setStrokeColorSpace':
args = [ColorSpace.parseToIR(args[0], xref, resources)];
break;
case 'shadingFill':
var shadingRes = xref.fetchIfRef(res.get('Shading'));
if (!shadingRes)
error('No shading resource found');
var shading = xref.fetchIfRef(shadingRes.get(args[0].name));
if (!shading)
error('No shading object found');
var shadingFill = Pattern.parseShading(shading, null, xref, res,
null);
var patternIR = shadingFill.getIR();
args = [patternIR];
fn = 'shadingFill';
break;
case 'setGState':
var dictName = args[0];
var extGState = xref.fetchIfRef(resources.get('ExtGState'));
if (!isDict(extGState) || !extGState.has(dictName.name))
break;
var gsState = xref.fetchIfRef(extGState.get(dictName.name));
// This array holds the converted/processed state data.
var gsStateObj = [];
gsState.forEach(
function canvasGraphicsSetGStateForEach(key, value) {
switch (key) {
case 'Type':
break;
case 'LW':
case 'LC':
case 'LJ':
case 'ML':
case 'D':
case 'RI':
case 'FL':
case 'CA':
case 'ca':
gsStateObj.push([key, value]);
break;
case 'Font':
gsStateObj.push([
'Font',
handleSetFont(null, value[0]),
value[1]
]);
break;
case 'OP':
case 'op':
case 'OPM':
case 'BG':
case 'BG2':
case 'UCR':
case 'UCR2':
case 'TR':
case 'TR2':
case 'HT':
case 'SM':
case 'SA':
case 'BM':
case 'SMask':
case 'AIS':
case 'TK':
TODO('graphic state operator ' + key);
break;
default:
warn('Unknown graphic state operator ' + key);
break;
}
}
);
args = [gsStateObj];
break;
} // switch
fnArray.push(fn);
argsArray.push(args);
args = [];
} else if (obj != null) {
assertWellFormed(args.length <= 33, 'Too many arguments');
args.push(obj);
}
}
return {
fnArray: fnArray,
argsArray: argsArray
};
},
extractDataStructures: function
partialEvaluatorExtractDataStructures(dict, baseDict,
xref, properties) {
// 9.10.2
var toUnicode = dict.get('ToUnicode') ||
baseDict.get('ToUnicode');
if (toUnicode)
properties.toUnicode = this.readToUnicode(toUnicode, xref);
if (properties.composite) {
// CIDSystemInfo helps to match CID to glyphs
var cidSystemInfo = xref.fetchIfRef(dict.get('CIDSystemInfo'));
if (isDict(cidSystemInfo)) {
properties.cidSystemInfo = {
registry: cidSystemInfo.get('Registry'),
ordering: cidSystemInfo.get('Ordering'),
supplement: cidSystemInfo.get('Supplement')
};
}
var cidToGidMap = xref.fetchIfRef(dict.get('CIDToGIDMap'));
if (isStream(cidToGidMap))
properties.cidToGidMap = this.readCidToGidMap(cidToGidMap);
}
var differences = [];
var baseEncoding = Encodings.StandardEncoding;
var hasEncoding = dict.has('Encoding');
if (hasEncoding) {
var encoding = xref.fetchIfRef(dict.get('Encoding'));
if (isDict(encoding)) {
var baseName = encoding.get('BaseEncoding');
if (baseName)
baseEncoding = Encodings[baseName.name];
else
hasEncoding = false; // base encoding was not provided
// Load the differences between the base and original
if (encoding.has('Differences')) {
var diffEncoding = encoding.get('Differences');
var index = 0;
for (var j = 0, jj = diffEncoding.length; j < jj; j++) {
var data = diffEncoding[j];
if (isNum(data))
index = data;
else
differences[index++] = data.name;
}
}
} else if (isName(encoding)) {
baseEncoding = Encodings[encoding.name];
} else {
error('Encoding is not a Name nor a Dict');
}
}
properties.differences = differences;
properties.baseEncoding = baseEncoding;
properties.hasEncoding = hasEncoding;
},
readToUnicode:
function partialEvaluatorReadToUnicode(toUnicode, xref) {
var cmapObj = xref.fetchIfRef(toUnicode);
var charToUnicode = [];
if (isName(cmapObj)) {
var isIdentityMap = cmapObj.name.substr(0, 9) == 'Identity-';
if (!isIdentityMap)
error('ToUnicode file cmap translation not implemented');
} else if (isStream(cmapObj)) {
var tokens = [];
var token = '';
var beginArrayToken = {};
var cmap = cmapObj.getBytes(cmapObj.length);
for (var i = 0, ii = cmap.length; i < ii; i++) {
var byte = cmap[i];
if (byte == 0x20 || byte == 0x0D || byte == 0x0A ||
byte == 0x3C || byte == 0x5B || byte == 0x5D) {
switch (token) {
case 'usecmap':
error('usecmap is not implemented');
break;
case 'beginbfchar':
case 'beginbfrange':
case 'begincidchar':
case 'begincidrange':
token = '';
tokens = [];
break;
case 'endcidrange':
case 'endbfrange':
for (var j = 0, jj = tokens.length; j < jj; j += 3) {
var startRange = tokens[j];
var endRange = tokens[j + 1];
var code = tokens[j + 2];
if (code == 0xFFFF) {
// CMap is broken, assuming code == startRange
code = startRange;
}
if (isArray(code)) {
var codeindex = 0;
while (startRange <= endRange) {
charToUnicode[startRange] = code[codeindex++];
++startRange;
}
} else {
while (startRange <= endRange) {
charToUnicode[startRange] = code++;
++startRange;
}
}
}
break;
case 'endcidchar':
case 'endbfchar':
for (var j = 0, jj = tokens.length; j < jj; j += 2) {
var index = tokens[j];
var code = tokens[j + 1];
charToUnicode[index] = code;
}
break;
case '':
break;
default:
if (token[0] >= '0' && token[0] <= '9')
token = parseInt(token, 10); // a number
tokens.push(token);
token = '';
}
switch (byte) {
case 0x5B:
// begin list parsing
tokens.push(beginArrayToken);
break;
case 0x5D:
// collect array items
var items = [], item;
while (tokens.length &&
(item = tokens.pop()) != beginArrayToken)
items.unshift(item);
tokens.push(items);
break;
}
} else if (byte == 0x3E) {
if (token.length) {
if (token.length <= 4) {
// parsing hex number
tokens.push(parseInt(token, 16));
token = '';
} else {
// parsing hex UTF-16BE numbers
var str = [];
for (var i = 0, ii = token.length; i < ii; i += 4)
str.push(parseInt(token.substr(i, 4), 16));
tokens.push(String.fromCharCode.apply(String, str));
token = '';
}
}
} else {
token += String.fromCharCode(byte);
}
}
}
return charToUnicode;
},
readCidToGidMap:
function partialEvaluatorReadCidToGidMap(cidToGidStream) {
// Extract the encoding from the CIDToGIDMap
var glyphsData = cidToGidStream.getBytes();
// Set encoding 0 to later verify the font has an encoding
var result = [];
for (var j = 0, jj = glyphsData.length; j < jj; j++) {
var glyphID = (glyphsData[j++] << 8) | glyphsData[j];
if (glyphID == 0)
continue;
var code = j >> 1;
result[code] = glyphID;
}
return result;
},
extractWidths: function partialEvaluatorWidths(dict,
xref,
descriptor,
properties) {
var glyphsWidths = [];
var defaultWidth = 0;
if (properties.composite) {
defaultWidth = xref.fetchIfRef(dict.get('DW')) || 1000;
var widths = xref.fetchIfRef(dict.get('W'));
if (widths) {
var start = 0, end = 0;
for (var i = 0, ii = widths.length; i < ii; i++) {
var code = widths[i];
if (isArray(code)) {
for (var j = 0, jj = code.length; j < jj; j++)
glyphsWidths[start++] = code[j];
start = 0;
} else if (start) {
var width = widths[++i];
for (var j = start; j <= code; j++)
glyphsWidths[j] = width;
start = 0;
} else {
start = code;
}
}
}
} else {
var firstChar = properties.firstChar;
var widths = xref.fetchIfRef(dict.get('Widths'));
if (widths) {
var j = firstChar;
for (var i = 0, ii = widths.length; i < ii; i++)
glyphsWidths[j++] = widths[i];
defaultWidth = parseFloat(descriptor.get('MissingWidth')) || 0;
} else {
// Trying get the BaseFont metrics (see comment above).
var baseFontName = dict.get('BaseFont');
if (isName(baseFontName)) {
var metrics = this.getBaseFontMetrics(baseFontName.name);
glyphsWidths = metrics.widths;
defaultWidth = metrics.defaultWidth;
}
}
}
properties.defaultWidth = defaultWidth;
properties.widths = glyphsWidths;
},
getBaseFontMetrics: function getBaseFontMetrics(name) {
var defaultWidth = 0, widths = [];
var glyphWidths = Metrics[stdFontMap[name] || name];
if (isNum(glyphWidths)) {
defaultWidth = glyphWidths;
} else {
widths = glyphWidths;
}
return {
defaultWidth: defaultWidth,
widths: widths
};
},
translateFont: function partialEvaluatorTranslateFont(dict, xref, resources,
dependency) {
var baseDict = dict;
var type = dict.get('Subtype');
assertWellFormed(isName(type), 'invalid font Subtype');
var composite = false;
if (type.name == 'Type0') {
// If font is a composite
// - get the descendant font
// - set the type according to the descendant font
// - get the FontDescriptor from the descendant font
var df = dict.get('DescendantFonts');
if (!df)
return null;
if (isRef(df))
df = xref.fetch(df);
dict = xref.fetchIfRef(isRef(df) ? df : df[0]);
type = dict.get('Subtype');
assertWellFormed(isName(type), 'invalid font Subtype');
composite = true;
}
var maxCharIndex = composite ? 0xFFFF : 0xFF;
var descriptor = xref.fetchIfRef(dict.get('FontDescriptor'));
if (!descriptor) {
if (type.name == 'Type3') {
// FontDescriptor is only required for Type3 fonts when the document
// is a tagged pdf. Create a barbebones one to get by.
descriptor = new Dict();
descriptor.set('FontName', new Name(type.name));
} else {
// Before PDF 1.5 if the font was one of the base 14 fonts, having a
// FontDescriptor was not required.
// This case is here for compatibility.
var baseFontName = dict.get('BaseFont');
if (!isName(baseFontName))
return null;
// Using base font name as a font name.
baseFontName = baseFontName.name.replace(/[,_]/g, '-');
var metrics = this.getBaseFontMetrics(baseFontName);
// Simulating descriptor flags attribute
var fontNameWoStyle = baseFontName.split('-')[0];
var flags = (serifFonts[fontNameWoStyle] ||
(fontNameWoStyle.search(/serif/gi) != -1) ? 2 : 0) |
(symbolsFonts[fontNameWoStyle] ? 4 : 32);
var properties = {
type: type.name,
widths: metrics.widths,
defaultWidth: metrics.defaultWidth,
flags: flags,
firstChar: 0,
lastChar: maxCharIndex
};
this.extractDataStructures(dict, dict, xref, properties);
return {
name: baseFontName,
dict: baseDict,
properties: properties
};
}
}
// According to the spec if 'FontDescriptor' is declared, 'FirstChar',
// 'LastChar' and 'Widths' should exists too, but some PDF encoders seems
// to ignore this rule when a variant of a standart font is used.
// TODO Fill the width array depending on which of the base font this is
// a variant.
var firstChar = xref.fetchIfRef(dict.get('FirstChar')) || 0;
var lastChar = xref.fetchIfRef(dict.get('LastChar')) || maxCharIndex;
var fontName = xref.fetchIfRef(descriptor.get('FontName'));
assertWellFormed(isName(fontName), 'invalid font name');
var fontFile = descriptor.get('FontFile', 'FontFile2', 'FontFile3');
if (fontFile) {
fontFile = xref.fetchIfRef(fontFile);
if (fontFile.dict) {
var subtype = fontFile.dict.get('Subtype');
if (subtype)
subtype = subtype.name;
var length1 = fontFile.dict.get('Length1');
if (!isInt(length1))
length1 = xref.fetchIfRef(length1);
var length2 = fontFile.dict.get('Length2');
if (!isInt(length2))
length2 = xref.fetchIfRef(length2);
}
}
var properties = {
type: type.name,
subtype: subtype,
file: fontFile,
length1: length1,
length2: length2,
composite: composite,
fixedPitch: false,
fontMatrix: dict.get('FontMatrix') || IDENTITY_MATRIX,
firstChar: firstChar || 0,
lastChar: lastChar || maxCharIndex,
bbox: descriptor.get('FontBBox'),
ascent: descriptor.get('Ascent'),
descent: descriptor.get('Descent'),
xHeight: descriptor.get('XHeight'),
capHeight: descriptor.get('CapHeight'),
flags: descriptor.get('Flags'),
italicAngle: descriptor.get('ItalicAngle'),
coded: false
};
this.extractWidths(dict, xref, descriptor, properties);
this.extractDataStructures(dict, baseDict, xref, properties);
if (type.name === 'Type3') {
properties.coded = true;
var charProcs = xref.fetchIfRef(dict.get('CharProcs'));
var fontResources = xref.fetchIfRef(dict.get('Resources')) || resources;
properties.resources = fontResources;
properties.charProcIRQueues = {};
for (var key in charProcs.map) {
var glyphStream = xref.fetchIfRef(charProcs.map[key]);
var queueObj = {};
properties.charProcIRQueues[key] =
this.getIRQueue(glyphStream, fontResources, queueObj, dependency);
}
}
return {
name: fontName.name,
dict: baseDict,
file: fontFile,
properties: properties
};
}
};
return PartialEvaluator;
})();
var EvalState = (function EvalStateClosure() {
function EvalState() {
// Are soft masks and alpha values shapes or opacities?
this.alphaIsShape = false;
this.fontSize = 0;
this.textMatrix = IDENTITY_MATRIX;
this.leading = 0;
// Start of text line (in text coordinates)
this.lineX = 0;
this.lineY = 0;
// Character and word spacing
this.charSpacing = 0;
this.wordSpacing = 0;
this.textHScale = 1;
// Color spaces
this.fillColorSpace = null;
this.strokeColorSpace = null;
}
EvalState.prototype = {
};
return EvalState;
})();