src/main/java/org/apache/sling/scripting/sightly/impl/filter/I18nFilter.java

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 * to you under the Apache License, Version 2.0 (the
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package org.apache.sling.scripting.sightly.impl.filter;

import java.util.Arrays;
import java.util.Collections;
import java.util.HashSet;
import java.util.Map;

import org.apache.sling.scripting.sightly.compiler.expression.Expression;
import org.apache.sling.scripting.sightly.compiler.expression.ExpressionNode;
import org.apache.sling.scripting.sightly.compiler.expression.nodes.MapLiteral;
import org.apache.sling.scripting.sightly.compiler.expression.nodes.RuntimeCall;

/**
 * Filter for i18n translation
 */
public final class I18nFilter extends AbstractFilter {

    public static final String I18N_OPTION = "i18n";
    public static final String HINT_OPTION = "hint";
    public static final String LOCALE_OPTION = "locale";
    public static final String BASENAME_OPTION = "basename";

    private static final class I18nFilterLoader {
        private static final I18nFilter INSTANCE = new I18nFilter();
    }

    private I18nFilter() {
        super(NON_PARAMETRIZABLE_CONTEXTS, new HashSet<>(Arrays.asList(I18N_OPTION, HINT_OPTION, LOCALE_OPTION, BASENAME_OPTION)), Collections.singleton(I18N_OPTION));
        priority = 90;
    }

    public static I18nFilter getInstance() {
        return I18nFilterLoader.INSTANCE;
    }

    @Override
    protected Expression apply(Expression expression, Map<String, ExpressionNode> options) {
        ExpressionNode translation = new RuntimeCall(RuntimeCall.I18N, expression.getRoot(), new MapLiteral(options));
        if (options.containsKey(LOCALE_OPTION)) {
            // put back the locale option, in case it will be used by the FormatFilter
            expression.getOptions().put(LOCALE_OPTION, options.get(LOCALE_OPTION));
        }
        return expression.withNode(translation);
    }
}