/*
 * Copyright (C) 2011 Red Hat, Inc. and/or its affiliates.
 *
 * Licensed 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 under the License.
 */

package org.jboss.errai.codegen.util;

import org.jboss.errai.codegen.Context;
import org.jboss.errai.codegen.Statement;
import org.jboss.errai.codegen.VariableReference;
import org.jboss.errai.codegen.exception.OutOfScopeException;
import org.jboss.errai.codegen.meta.MetaClass;

/**
 * @author Mike Brock <cbrock@redhat.com>
 */
public abstract class Refs {
  public static VariableReference get(final String name, final MetaClass type) {
    return new VariableReference() {
      @Override
      public String getName() {
        return name;
      }

      @Override
      public Statement getValue() {
        return new Statement() {
          @Override
          public String generate(Context context) {
            return name;
          }

          @Override
          public MetaClass getType() {
            return type;
          }
        };
      }
    };
  }

  public static VariableReference get(final String name) {
    return new VariableReference() {
      private MetaClass type;

      @Override
      public String getName() {
        return name;
      }

      @Override
      public Statement getValue() {
        return new Statement() {

          String generatedCache;

          @Override
          public String generate(final Context context) {
            if (generatedCache != null) return generatedCache;

            final VariableReference var = context.getVariable(name);

            if (var == null) {
              throw new OutOfScopeException("could not access variable: " + name);
            }

            type = var.getType();

            return generatedCache = name;
          }

          @Override
          public MetaClass getType() {
            return type;
          }
        };
      }

      @Override
      public String generate(final Context context) {
        return getValue().generate(context);
      }

      @Override
      public MetaClass getType() {
        return type;
      }

      @Override
      public String toString() {
        return "[var-ref:" + name + "::" + type + "]";
      }
    };
  }
}