Many resources are needed to download a project. Please understand that we have to compensate our server costs. Thank you in advance. Project price only 1 $
You can buy this project and download/modify it how often you want.
/*
This file is part of the iText (R) project.
Copyright (c) 1998-2023 Apryse Group NV
Authors: Apryse Software.
This program is offered under a commercial and under the AGPL license.
For commercial licensing, contact us at https://itextpdf.com/sales. For AGPL licensing, see below.
AGPL licensing:
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Affero General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Affero General Public License for more details.
You should have received a copy of the GNU Affero General Public License
along with this program. If not, see .
*/
package com.itextpdf.styledxmlparser.css.util;
import com.itextpdf.layout.font.RangeBuilder;
import com.itextpdf.styledxmlparser.CommonAttributeConstants;
import com.itextpdf.styledxmlparser.node.IElementNode;
import com.itextpdf.layout.font.Range;
import com.itextpdf.layout.properties.BlendMode;
import com.itextpdf.styledxmlparser.css.CommonCssConstants;
import com.itextpdf.styledxmlparser.css.parse.CssDeclarationValueTokenizer;
import com.itextpdf.styledxmlparser.css.parse.CssDeclarationValueTokenizer.Token;
import com.itextpdf.styledxmlparser.css.parse.CssDeclarationValueTokenizer.TokenType;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.util.ArrayList;
import java.util.List;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Utilities class for CSS operations.
*/
public class CssUtils {
private static final float EPSILON = 1e-6f;
private static final Logger logger = LoggerFactory.getLogger(CssUtils.class);
private static final int QUANTITY_OF_PARAMS_WITH_FALLBACK_OR_TYPE = 2;
/**
* Creates a new {@link CssUtils} instance.
*/
private CssUtils() {
// Empty constructor
}
/**
* Splits the provided {@link String} by comma with respect of brackets.
*
* @param value to split
* @return the {@link List} of split result
*/
public static List splitStringWithComma(final String value) {
return splitString(value, ',', new EscapeGroup('(', ')'));
}
/**
* Splits the provided {@link String} by split character with respect of escape characters.
*
* @param value value to split
* @param splitChar character to split the String
* @param escapeCharacters escape characters
* @return the {@link List} of split result
*/
public static List splitString(String value, char splitChar, EscapeGroup... escapeCharacters) {
if (value == null) {
return new ArrayList<>();
}
final List resultList = new ArrayList<>();
int lastSplitChar = 0;
for (int i = 0; i < value.length(); ++i) {
final char currentChar = value.charAt(i);
boolean isEscaped = false;
for (final EscapeGroup character : escapeCharacters) {
if (currentChar == splitChar) {
isEscaped = isEscaped || character.isEscaped();
} else {
character.processCharacter(currentChar);
}
}
if (currentChar == splitChar && !isEscaped) {
resultList.add(value.substring(lastSplitChar, i));
lastSplitChar = i + 1;
}
}
final String lastToken = value.substring(lastSplitChar);
if (!lastToken.isEmpty()) {
resultList.add(lastToken);
}
return resultList;
}
/**
* Parses the given css blend mode value. If the argument is {@code null} or an unknown blend
* mode, then the default css {@link BlendMode#NORMAL} value would be returned.
*
* @param cssValue the value to parse
* @return the {@link BlendMode} instance representing the parsed value
*/
public static BlendMode parseBlendMode(String cssValue) {
if (cssValue == null) {
return BlendMode.NORMAL;
}
switch (cssValue) {
case CommonCssConstants.MULTIPLY:
return BlendMode.MULTIPLY;
case CommonCssConstants.SCREEN:
return BlendMode.SCREEN;
case CommonCssConstants.OVERLAY:
return BlendMode.OVERLAY;
case CommonCssConstants.DARKEN:
return BlendMode.DARKEN;
case CommonCssConstants.LIGHTEN:
return BlendMode.LIGHTEN;
case CommonCssConstants.COLOR_DODGE:
return BlendMode.COLOR_DODGE;
case CommonCssConstants.COLOR_BURN:
return BlendMode.COLOR_BURN;
case CommonCssConstants.HARD_LIGHT:
return BlendMode.HARD_LIGHT;
case CommonCssConstants.SOFT_LIGHT:
return BlendMode.SOFT_LIGHT;
case CommonCssConstants.DIFFERENCE:
return BlendMode.DIFFERENCE;
case CommonCssConstants.EXCLUSION:
return BlendMode.EXCLUSION;
case CommonCssConstants.HUE:
return BlendMode.HUE;
case CommonCssConstants.SATURATION:
return BlendMode.SATURATION;
case CommonCssConstants.COLOR:
return BlendMode.COLOR;
case CommonCssConstants.LUMINOSITY:
return BlendMode.LUMINOSITY;
case CommonCssConstants.NORMAL:
default:
return BlendMode.NORMAL;
}
}
/**
* Extracts shorthand properties as list of string lists from a string, where the top level
* list is shorthand property and the lower level list is properties included in shorthand property.
*
* @param str the source string with shorthand properties
* @return the list of string lists
*/
public static List> extractShorthandProperties(String str) {
List> result = new ArrayList<>();
List currentLayer = new ArrayList<>();
CssDeclarationValueTokenizer tokenizer = new CssDeclarationValueTokenizer(str);
Token currentToken = tokenizer.getNextValidToken();
while (currentToken != null) {
if (currentToken.getType() == TokenType.COMMA) {
result.add(currentLayer);
currentLayer = new ArrayList<>();
} else {
currentLayer.add(currentToken.getValue());
}
currentToken = tokenizer.getNextValidToken();
}
result.add(currentLayer);
return result;
}
/**
* Normalizes a CSS property.
*
* @param str the property
* @return the normalized property
*/
public static String normalizeCssProperty(String str) {
return str == null ? null : CssPropertyNormalizer.normalize(str);
}
/**
* Removes double spaces and trims a string.
*
* @param str the string
* @return the string without the unnecessary spaces
*/
public static String removeDoubleSpacesAndTrim(String str) {
String[] parts = str.split("\\s");
StringBuilder sb = new StringBuilder();
for (String part : parts) {
if (part.length() > 0) {
if (sb.length() != 0) {
sb.append(" ");
}
sb.append(part);
}
}
return sb.toString();
}
/**
* Parses {@code url("file.jpg")} to {@code file.jpg}.
*
* @param url the url attribute to parse
* @return the parsed url. Or original url if not wrappend in url()
*/
public static String extractUrl(final String url) {
String str = null;
if (url.startsWith("url")) {
String urlString = url.substring(3).trim().replace("(", "").replace(")", "").trim();
if (urlString.startsWith("'") && urlString.endsWith("'")) {
str = urlString.substring(urlString.indexOf("'") + 1, urlString.lastIndexOf("'"));
} else if (urlString.startsWith("\"") && urlString.endsWith("\"")) {
str = urlString.substring(urlString.indexOf('"') + 1, urlString.lastIndexOf('"'));
} else {
str = urlString;
}
} else {
// assume it's an url without wrapping in "url()"
str = url;
}
return str;
}
/**
* Parses string and return attribute value.
*
* @param attrStr the string contains attr() to extract attribute value
* @param element the parentNode from which we extract information
* @return the value of attribute
*/
public static String extractAttributeValue(final String attrStr, IElementNode element) {
String attrValue = null;
if (attrStr.startsWith(CommonCssConstants.ATTRIBUTE + '(')
&& attrStr.length() > CommonCssConstants.ATTRIBUTE.length() + 2 && attrStr.endsWith(")")) {
String fallback = null;
String typeOfAttribute = null;
final String stringToSplit = attrStr.substring(5, attrStr.length() - 1);
final List paramsWithFallback = splitString(stringToSplit, ',', new EscapeGroup('\"'),
new EscapeGroup('\''));
if (paramsWithFallback.size() > QUANTITY_OF_PARAMS_WITH_FALLBACK_OR_TYPE) {
return null;
}
if (paramsWithFallback.size() == QUANTITY_OF_PARAMS_WITH_FALLBACK_OR_TYPE) {
fallback = extractFallback(paramsWithFallback.get(1));
}
final List params = splitString(paramsWithFallback.get(0), ' ');
if (params.size() > QUANTITY_OF_PARAMS_WITH_FALLBACK_OR_TYPE) {
return null;
}
if (params.size() == QUANTITY_OF_PARAMS_WITH_FALLBACK_OR_TYPE) {
typeOfAttribute = extractTypeOfAttribute(params.get(1));
if (typeOfAttribute == null) {
return null;
}
}
String attributeName = params.get(0);
if (isAttributeNameValid(attributeName)) {
attrValue = getAttributeValue(attributeName, typeOfAttribute, fallback, element);
}
}
return attrValue;
}
/**
* Find the next unescaped character.
*
* @param source a source
* @param ch the character to look for
* @param startIndex where to start looking
* @return the position of the next unescaped character
*/
public static int findNextUnescapedChar(String source, char ch, int startIndex) {
int symbolPos = source.indexOf(ch, startIndex);
if (symbolPos == -1) {
return -1;
}
int afterNoneEscapePos = symbolPos;
while (afterNoneEscapePos > 0 && source.charAt(afterNoneEscapePos - 1) == '\\') {
--afterNoneEscapePos;
}
return (symbolPos - afterNoneEscapePos) % 2 == 0 ? symbolPos : findNextUnescapedChar(source, ch, symbolPos + 1);
}
/**
* Helper method for comparing floating point numbers
*
* @param d1 first float to compare
* @param d2 second float to compare
* @return True if both floats are equal within a Epsilon defined in this class, false otherwise
*/
public static boolean compareFloats(double d1, double d2) {
return (Math.abs(d1 - d2) < EPSILON);
}
/**
* Helper method for comparing floating point numbers
*
* @param f1 first float to compare
* @param f2 second float to compare
* @return True if both floats are equal within a Epsilon defined in this class, false otherwise
*/
public static boolean compareFloats(float f1, float f2) {
return (Math.abs(f1 - f2) < EPSILON);
}
/**
* Parses the unicode range.
*
* @param unicodeRange the string which stores the unicode range
* @return the unicode range as a {@link Range} object
*/
public static Range parseUnicodeRange(String unicodeRange) {
String[] ranges = unicodeRange.split(",");
RangeBuilder builder = new RangeBuilder();
for (String range : ranges) {
if (!addRange(builder, range)) {
return null;
}
}
return builder.create();
}
/**
* Convert given point value to a pixel value. 1 px is 0.75 pts.
*
* @param pts float value to be converted to pixels
* @return float converted value pts/0.75f
*/
public static float convertPtsToPx(float pts) {
return pts / 0.75f;
}
/**
* Convert given point value to a pixel value. 1 px is 0.75 pts.
*
* @param pts double value to be converted to pixels
* @return double converted value pts/0.75
*/
public static double convertPtsToPx(double pts) {
return pts / 0.75;
}
/**
* Convert given point value to a point value. 1 px is 0.75 pts.
*
* @param px float value to be converted to pixels
* @return float converted value px*0.75
*/
public static float convertPxToPts(float px) {
return px * 0.75f;
}
/**
* Convert given point value to a point value. 1 px is 0.75 pts.
*
* @param px double value to be converted to pixels
* @return double converted value px*0.75
*/
public static double convertPxToPts(double px) {
return px * 0.75;
}
/**
* Checks if an {@link IElementNode} represents a style sheet link.
*
* @param headChildElement the head child element
* @return true, if the element node represents a style sheet link
*/
public static boolean isStyleSheetLink(IElementNode headChildElement) {
return CommonCssConstants.LINK.equals(headChildElement.name())
&& CommonAttributeConstants.STYLESHEET
.equals(headChildElement.getAttribute(CommonAttributeConstants.REL));
}
private static boolean addRange(RangeBuilder builder, String range) {
range = range.trim();
if (range.matches("[uU]\\+[0-9a-fA-F?]{1,6}(-[0-9a-fA-F]{1,6})?")) {
String[] parts = range.substring(2, range.length()).split("-");
if (1 == parts.length) {
if (parts[0].contains("?")) {
return addRange(builder, parts[0].replace('?', '0'), parts[0].replace('?', 'F'));
} else {
return addRange(builder, parts[0], parts[0]);
}
} else {
return addRange(builder, parts[0], parts[1]);
}
}
return false;
}
private static boolean addRange(RangeBuilder builder, String left, String right) {
int l = Integer.parseInt(left, 16);
int r = Integer.parseInt(right, 16);
if (l > r || r > 1114111) {
// Although Firefox follows the spec (and therefore the second condition), it seems it's ignored in Chrome or Edge
return false;
}
builder.addRange(l, r);
return true;
}
private static boolean isAttributeNameValid(String attributeName) {
return !(attributeName.contains("'") || attributeName.contains("\"") || attributeName.contains("(")
|| attributeName.contains(")"));
}
private static String extractFallback(String fallbackString) {
String tmpString;
if ((fallbackString.startsWith("'") && fallbackString.endsWith("'")) || (fallbackString.startsWith("\"")
&& fallbackString.endsWith("\""))) {
tmpString = fallbackString.substring(1, fallbackString.length() - 1);
} else {
tmpString = fallbackString;
}
return extractUrl(tmpString);
}
private static String extractTypeOfAttribute(String typeString) {
if (typeString.equals(CommonCssConstants.URL) || typeString.equals(CommonCssConstants.STRING)) {
return typeString;
}
return null;
}
private static String getAttributeValue(final String attributeName, final String typeOfAttribute,
final String fallback,
IElementNode elementNode) {
String returnString = elementNode.getAttribute(attributeName);
if (CommonCssConstants.URL.equals(typeOfAttribute)) {
returnString = returnString == null ? null : extractUrl(returnString);
} else {
returnString = returnString == null ? "" : returnString;
}
if (fallback != null && (returnString == null || returnString.isEmpty())) {
returnString = fallback;
}
return returnString;
}
}
