/*
* Copyright 2011, The gwtquery team.
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may not
* use this file except in compliance with the License. You may obtain a copy of
* the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations under
* the License.
*/
package com.google.gwt.query.client.impl;
import java.util.ArrayList;
import com.google.gwt.core.client.GWT;
import com.google.gwt.core.client.JsArray;
import com.google.gwt.dom.client.Element;
import com.google.gwt.dom.client.Node;
import com.google.gwt.dom.client.NodeList;
import com.google.gwt.query.client.js.JsNamedArray;
import com.google.gwt.query.client.js.JsNodeArray;
import com.google.gwt.query.client.js.JsUtils;
import com.google.gwt.regexp.shared.MatchResult;
import com.google.gwt.regexp.shared.RegExp;
/**
* Runtime selector engine implementation which translates selectors to XPath
* and delegates to document.evaluate().
* It is based on the regular expressions taken from Andrea Giammarchi's Css2Xpath
*/
public class SelectorEngineCssToXPath extends SelectorEngineImpl {
static JsNamedArray<String> cache;
/**
* Interface for callbacks in replaceAll operations.
*/
public static interface ReplaceCallback {
String foundMatch(ArrayList<String> s);
}
/**
* Interface for replacer implementations (GWT and JVM).
*/
public static interface Replacer {
String replaceAll(String s, String expr, Object replacement);
}
private static SelectorEngineCssToXPath instance;
private static ReplaceCallback rc_scp = new ReplaceCallback() {
public String foundMatch(ArrayList<String> s) {
return s.get(1) + s.get(2) +
(s.get(3).startsWith(" ") ? "%S%" : s.get(3).startsWith("#") ? "%H%" : "%P%") +
s.get(4) + s.get(5);
}
};
private static ReplaceCallback rc_$Attr = new ReplaceCallback() {
public String foundMatch(ArrayList<String> s) {
return "[substring(@" + s.get(1) + ",string-length(@" + s.get(1) + ")-" + (s.get(2).replaceAll("'", "").length() - 1) + ")=" + s.get(2) + "]";
}
};
private static ReplaceCallback rc_Not = new ReplaceCallback() {
public String foundMatch(ArrayList<String> s) {
return s.get(1) + "[not(" + getInstance().css2Xpath(s.get(2)).replaceAll("^[^\\[]+\\[([^\\]]*)\\].*$", "$1" + ")]");
}
};
private static ReplaceCallback rc_nth_child = new ReplaceCallback() {
public String foundMatch(ArrayList<String> s) {
String s1 = s.get(1);
String s2 = s.get(2);
boolean afterAttr = "]".equals(s1);
String prefix = afterAttr ? s1 : "*";
boolean noPrefix = afterAttr || s1 == null || s1.length() == 0 ;
if ("n".equals(s2)) {
return s1;
}
if ("even".equals(s2)) {
return prefix + "[position() mod 2=0 and position()>=0]" + (noPrefix ? "" : "/self::" + s1);
}
if ("odd".equals(s2)) {
prefix = afterAttr ? prefix : noPrefix ? "" : s1;
return prefix + "[(count(preceding-sibling::*) + 1) mod 2=1]";
}
if (!s2.contains("n")){
return prefix + "[position() = "+s2+"]" + (noPrefix ? "" : "/self::" + s1);
}
String[] t = s2.replaceAll("^([0-9]*)n.*?([0-9]*)?$", "$1+$2").split("\\+");
String t0 = t[0];
String t1 = t.length > 1 ? t[1] : "0";
return prefix + "[(position()-" + t1 + ") mod " + t0 + "=0 and position()>=" + t1 + "]" + (noPrefix ? "" : "/self::" + s1);
}
};
public static Object[] regs = new Object[]{
// scape some dots and spaces
"(['\\[])([^'\\]]*)([\\s\\.#])([^'\\]]*)(['\\]])", rc_scp,
// add @ for attrib
"\\[([^@\\]~\\$\\*\\^\\|\\!]+)(=[^\\]]+)?\\]", "[@$1$2]",
// multiple queries
"\\s*,\\s*", "|.//",
// , + ~ >
"\\s*(\\+|~|>)\\s*", "$1",
//* ~ + >
"([\\w\\-\\*])~([\\w\\-\\*])", "$1/following-sibling::$2",
"([\\w\\-\\*])\\+([\\w\\-\\*])", "$1/following-sibling::*[1]/self::$2",
"([\\w\\-\\*])>([\\w\\-\\*])", "$1/$2",
// all unescaped stuff escaped
"\\[([^=]+)=([^'|\"][^\\]]*)\\]", "[$1='$2']",
// all descendant or self to
"(^|[^\\w\\-\\*])(#|\\.)([\\w\\-]+)", "$1*$2$3",
"([\\>\\+\\|\\~\\,\\s])([a-zA-Z\\*]+)", "$1//$2",
"\\s+//", "//",
// :first-child
"([\\w\\-\\*]+):first-child", "*[1]/self::$1",
// :last-child
"([\\w\\-\\*]+):last-child", "$1[not(following-sibling::*)]",
// :only-child
"([\\w\\-\\*]+):only-child", "*[last()=1]/self::$1",
// :empty
"([\\w\\-\\*]+):empty", "$1[not(*) and not(normalize-space())]",
// :odd :even, this is intentional since sizzle behaves so
":odd" , ":nth-child(even)",
":even" , ":nth-child(odd)",
// :not
"(.+):not\\(([^\\)]*)\\)", rc_Not,
// :nth-child
"([a-zA-Z0-9\\_\\-\\*]*|\\]):nth-child\\(([^\\)]*)\\)", rc_nth_child,
// :contains(selectors)
":contains\\(([^\\)]*)\\)", "[contains(string(.),'$1')]",
// |= attrib
"\\[([\\w\\-]+)\\|=([^\\]]+)\\]", "[@$1=$2 or starts-with(@$1,concat($2,'-'))]",
// *= attrib
"\\[([\\w\\-]+)\\*=([^\\]]+)\\]", "[contains(@$1,$2)]",
// ~= attrib
"\\[([\\w\\-]+)~=([^\\]]+)\\]", "[contains(concat(' ',normalize-space(@$1),' '),concat(' ',$2,' '))]",
// ^= attrib
"\\[([\\w\\-]+)\\^=([^\\]]+)\\]", "[starts-with(@$1,$2)]",
// $= attrib
"\\[([\\w\\-]+)\\$=([^\\]]+)\\]", rc_$Attr,
// != attrib
"\\[([\\w\\-]+)\\!=([^\\]]+)\\]", "[not(@$1) or @$1!=$2]",
// ids and classes
"#([\\w\\-]+)", "[@id='$1']",
"\\.([\\w\\-]+)", "[contains(concat(' ',normalize-space(@class),' '),' $1 ')]",
// normalize multiple filters
"\\]\\[([^\\]]+)", " and ($1)",
// tag:pseudo
":(enabled)", "[not(@disabled)]",
":(checked)", "[@$1='$1']",
":(disabled)", "[@$1]",
":(first)", "[1]",
":(last)", "[last()]",
// put '*' when tag is omitted
"(^|\\|[\\./]*)(\\[)", "$1*$2",
// Replace escaped dots and spaces
"%S%"," ",
"%P%",".",
"%H%","#",
// Duplicated quotes
"'+","'",
};
public static SelectorEngineCssToXPath getInstance() {
if (instance == null) {
instance = new SelectorEngineCssToXPath();
}
return instance;
}
// This replacer only works in browser, it must be replaced
// when using this engine in generators and tests for the JVM
private Replacer replacer = new Replacer() {
public String replaceAll(String s, String r, Object o) {
RegExp p = RegExp.compile(r);
if (o instanceof ReplaceCallback) {
ReplaceCallback callback = (ReplaceCallback) o;
while (p.test(s)) {
MatchResult a = p.exec(s);
ArrayList<String> args = new ArrayList<String>();
for (int i = 0; a != null && i < a.getGroupCount(); i++) {
args.add(a.getGroup(i));
}
String f = callback.foundMatch(args);
s = s.replaceFirst(r, f);
}
return s;
} else {
return s.replaceAll(r, o.toString());
}
}
};
/**
* A replacer which works in both sides. Right now gquery JsRegexp is faster
* than gwt shared RegExp and does not uses HashSet
*/
public static final Replacer replacerGwt = new Replacer() {
public String replaceAll(String s, String r, Object o) {
RegExp p = RegExp.compile(r, "g");
if (o instanceof ReplaceCallback) {
ReplaceCallback callback = (ReplaceCallback) o;
com.google.gwt.regexp.shared.MatchResult a = null;
while ((a = p.exec(s)) != null) {
ArrayList<String> args = new ArrayList<String>();
for (int i = 0; i < a.getGroupCount(); i++) {
args.add(a.getGroup(i));
}
String f = callback.foundMatch(args);
s = s.replace(a.getGroup(0), f);
p = RegExp.compile(r, "g");
}
return s;
} else {
return p.replace(s, o.toString());
}
}
};
public SelectorEngineCssToXPath() {
instance = this;
}
public SelectorEngineCssToXPath(Replacer r) {
replacer = r;
instance = this;
}
public String css2Xpath(String selector) {
String ret = selector;
for (int i = 0; i < regs.length;) {
ret = replacer.replaceAll(ret, regs[i++].toString(), regs[i++]);
}
return ".//" + ret;
}
public NodeList<Element> select(String sel, Node ctx) {
if (cache == null) {
cache = JsNamedArray.create();
}
String xsel = cache.get(sel);
if (xsel == null) {
xsel = sel.startsWith("./") || sel.startsWith("/") ? sel : css2Xpath(sel);
cache.put(sel, xsel);
}
JsNodeArray elm = JsNodeArray.create();
try {
SelectorEngine.xpathEvaluate(xsel, ctx, elm);
return JsUtils.unique(elm.<JsArray<Element>> cast()).cast();
} catch (Exception e) {
if (!GWT.isScript()) {
if (!SelectorEngine.hasXpathEvaluate()) {
throw new RuntimeException("This Browser does not support Xpath selectors.", e);
}
System.err.println("ERROR: xpathEvaluate invalid xpath expression:"
+ xsel + " css-selector:" + sel + "\n");
e.printStackTrace();
}
return elm;
}
}
}