org.jline.style.StyleExpression Maven / Gradle / Ivy
/*
* Copyright (c) 2002-2018, the original author or authors.
*
* This software is distributable under the BSD license. See the terms of the
* BSD license in the documentation provided with this software.
*
* https://opensource.org/licenses/BSD-3-Clause
*/
package org.jline.style;
import org.jline.utils.AttributedString;
import org.jline.utils.AttributedStringBuilder;
import org.jline.utils.AttributedStyle;
import java.util.regex.Pattern;
import static java.util.Objects.requireNonNull;
/**
* Provides {@code @{style value}} expression evaluation.
*
* @since 3.4
*/
public class StyleExpression {
private final StyleResolver resolver;
public StyleExpression() {
this(new StyleResolver(new NopStyleSource(), ""));
}
public StyleExpression(final StyleResolver resolver) {
this.resolver = requireNonNull(resolver);
}
/**
* Evaluate expression and append to buffer.
*
* @param buff the buffer to append to
* @param expression the expression to evaluate
*/
public void evaluate(final AttributedStringBuilder buff, final String expression) {
requireNonNull(buff);
requireNonNull(expression);
String translated = InterpolationHelper.substVars(expression, this::style, false);
buff.appendAnsi(translated);
}
private String style(String key) {
int idx = key.indexOf(' ');
if (idx > 0) {
String spec = key.substring(0, idx);
String value = key.substring(idx + 1);
AttributedStyle style = resolver.resolve(spec);
return new AttributedStringBuilder().style(style).ansiAppend(value).toAnsi();
}
return null;
}
/**
* Evaluate expression.
*
* @param expression the expression to evaluate
* @return the result string
*/
public AttributedString evaluate(final String expression) {
AttributedStringBuilder buff = new AttributedStringBuilder();
evaluate(buff, expression);
return buff.toAttributedString();
}
}