/*
 * Copyright (c) MuleSoft, Inc.  All rights reserved.  http://www.mulesoft.com
 * The software in this package is published under the terms of the CPAL v1.0
 * license, a copy of which has been included with this distribution in the
 * LICENSE.txt file.
 */
package org.mule.runtime.core.el.mvel;

import org.mule.runtime.core.api.MuleContext;
import org.mule.runtime.core.api.el.ExpressionLanguageExtension;
import org.mule.mvel2.ParserConfiguration;
import org.mule.mvel2.ast.Function;
import org.mule.mvel2.ast.FunctionInstance;

import java.util.List;
import java.util.Map;
import java.util.Map.Entry;

public class GlobalVariableResolverFactory extends MVELExpressionLanguageContext {

  private static final long serialVersionUID = -6819292692339684915L;

  // Minor optimization to avoid HashMap contains if it can be avoided.
  private boolean hasTarget = false;

  public GlobalVariableResolverFactory(Map<String, String> aliases, Map<String, Function> functions,
                                       ParserConfiguration parserConfiguration, MuleContext muleContext) {
    super(parserConfiguration, muleContext);
    List<ExpressionLanguageExtension> extensions = (List<ExpressionLanguageExtension>) muleContext.getRegistry()
        .lookupObjectsForLifecycle(ExpressionLanguageExtension.class);

    hasTarget = !(aliases.isEmpty() && functions.isEmpty() && extensions.isEmpty());

    for (ExpressionLanguageExtension extension : extensions) {
      extension.configureContext(this);
    }
    for (Entry<String, String> alias : aliases.entrySet()) {
      addAlias(alias.getKey(), alias.getValue());
    }
    for (Entry<String, Function> function : functions.entrySet()) {
      addFinalVariable(function.getKey(), new FunctionInstance(function.getValue()));
    }
  }

  @Override
  public boolean isTarget(String name) {
    return hasTarget && super.isTarget(name);
  }

}