package net.sf.saxon.style;
import net.sf.saxon.expr.*;
import net.sf.saxon.functions.Concat;
import net.sf.saxon.functions.SystemFunction;
import net.sf.saxon.instruct.SimpleContentConstructor;
import net.sf.saxon.trans.XPathException;
import net.sf.saxon.type.BuiltInAtomicType;
import net.sf.saxon.type.TypeHierarchy;
import net.sf.saxon.value.Cardinality;
import net.sf.saxon.value.StringValue;
import java.util.ArrayList;
import java.util.List;
/**
* This class represents an attribute value template. The class allows an AVT to be parsed, and
* can construct an Expression that returns the effective value of the AVT.
*
* This is an abstract class that is never instantiated, it contains static methods only.
*/
public abstract class AttributeValueTemplate {
private AttributeValueTemplate() {}
/**
* Static factory method to create an AVT from an XSLT string representation.
*/
public static Expression make(String avt,
int lineNumber,
StaticContext env) throws XPathException {
List components = new ArrayList(5);
int i0, i1, i8, i9;
int len = avt.length();
int last = 0;
ExpressionVisitor visitor = ExpressionVisitor.make(env);
while (last < len) {
i0 = avt.indexOf("{", last);
i1 = avt.indexOf("{{", last);
i8 = avt.indexOf("}", last);
i9 = avt.indexOf("}}", last);
if ((i0 < 0 || len < i0) && (i8 < 0 || len < i8)) { // found end of string
addStringComponent(components, avt, last, len);
break;
} else if (i8 >= 0 && (i0 < 0 || i8 < i0)) { // found a "}"
if (i8 != i9) { // a "}" that isn't a "}}"
XPathException err = new XPathException("Closing curly brace in attribute value template \"" + avt.substring(0, len) + "\" must be doubled");
err.setErrorCode("XTSE0370");
err.setIsStaticError(true);
throw err;
}
addStringComponent(components, avt, last, i8 + 1);
last = i8 + 2;
} else if (i1 >= 0 && i1 == i0) { // found a doubled "{{"
addStringComponent(components, avt, last, i1 + 1);
last = i1 + 2;
} else if (i0 >= 0) { // found a single "{"
if (i0 > last) {
addStringComponent(components, avt, last, i0);
}
Expression exp;
ExpressionParser parser = new ExpressionParser();
exp = parser.parse(avt, i0 + 1, Token.RCURLY, lineNumber, env);
exp = visitor.simplify(exp);
last = parser.getTokenizer().currentTokenStartOffset + 1;
if (env.isInBackwardsCompatibleMode()) {
components.add(makeFirstItem(exp, env));
} else {
components.add(visitor.simplify(
new SimpleContentConstructor(exp, new StringLiteral(StringValue.SINGLE_SPACE))));
}
} else {
throw new IllegalStateException("Internal error parsing AVT");
}
}
// is it empty?
if (components.size() == 0) {
return new StringLiteral(StringValue.EMPTY_STRING);
}
// is it a single component?
if (components.size() == 1) {
return visitor.simplify((Expression) components.get(0));
}
// otherwise, return an expression that concatenates the components
Expression[] args = new Expression[components.size()];
components.toArray(args);
Concat fn = (Concat) SystemFunction.makeSystemFunction("concat", args);
fn.setLocationId(env.getLocationMap().allocateLocationId(env.getSystemId(), lineNumber));
return visitor.simplify(fn);
}
private static void addStringComponent(List components, String avt, int start, int end) {
if (start < end) {
components.add(new StringLiteral(avt.substring(start, end)));
}
}
/**
* Make an expression that extracts the first item of a sequence, after atomization
*/
public static Expression makeFirstItem(Expression exp, StaticContext env) {
final TypeHierarchy th = env.getConfiguration().getTypeHierarchy();
if (!exp.getItemType(th).isAtomicType()) {
exp = new Atomizer(exp);
}
if (Cardinality.allowsMany(exp.getCardinality())) {
exp = new FirstItemExpression(exp);
}
if (!th.isSubType(exp.getItemType(th), BuiltInAtomicType.STRING)) {
exp = new AtomicSequenceConverter(exp, BuiltInAtomicType.STRING);
}
return exp;
}
}
//
// The contents of this file are subject to the Mozilla Public License Version 1.0 (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.mozilla.org/MPL/
//
// Software distributed under the License is distributed on an "AS IS" basis,
// WITHOUT WARRANTY OF ANY KIND, either express or implied.
// See the License for the specific language governing rights and limitations under the License.
//
// The Original Code is: all this file.
//
// The Initial Developer of the Original Code is Michael H. Kay.
//
// Portions created by (your name) are Copyright (C) (your legal entity). All Rights Reserved.
//
// Contributor(s): none.
//