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 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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
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package org.apache.sling.scripting.sightly.impl.plugin;

import org.apache.sling.scripting.sightly.compiler.SightlyCompilerException;
import org.apache.sling.scripting.sightly.compiler.commands.Procedure;
import org.apache.sling.scripting.sightly.compiler.commands.VariableBinding;
import org.apache.sling.scripting.sightly.compiler.expression.Expression;
import org.apache.sling.scripting.sightly.compiler.expression.nodes.MapLiteral;
import org.apache.sling.scripting.sightly.impl.compiler.Patterns;
import org.apache.sling.scripting.sightly.impl.compiler.PushStream;
import org.apache.sling.scripting.sightly.impl.compiler.frontend.CompilerContext;

public class CallPlugin extends AbstractPlugin {

    public CallPlugin() {
        name = "call";
        priority = 3;
    }

    @Override
    public PluginInvoke invoke(final Expression expression,
                               final PluginCallInfo callInfo,
                               final CompilerContext compilerContext) {
        if (callInfo.getArguments().length > 0) {
            throw new SightlyCompilerException("Call plugin should have no arguments.", "data-sly-call." + callInfo.getArguments()[0]);
        }
        return new DefaultPluginInvoke() {

            @Override
            public void beforeChildren(PushStream stream) {
                String templateVar = compilerContext.generateVariable("templateVar");
                String argsVar = compilerContext.generateVariable("templateOptions");
                MapLiteral args = new MapLiteral(expression.getOptions());
                stream.write(new VariableBinding.Start(templateVar, expression.getRoot()));
                stream.write(new VariableBinding.Start(argsVar, args));
                stream.write(new Procedure.Call(templateVar, argsVar));
                stream.write(VariableBinding.END);
                stream.write(VariableBinding.END);
                //ignoring everything else
                Patterns.beginStreamIgnore(stream);
            }

            @Override
            public void afterChildren(PushStream stream) {
                Patterns.endStreamIgnore(stream);
            }

        };
    }
}