/*
 * Copyright (C) 2009 Google Inc.
 *
 * 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.elasticsearch.common.inject.internal;

import org.elasticsearch.common.inject.Binder;
import org.elasticsearch.common.inject.Key;
import org.elasticsearch.common.inject.binder.AnnotatedElementBuilder;

import java.lang.annotation.Annotation;
import java.util.Objects;

/**
 * For private binder's expose() method.
 */
public class ExposureBuilder<T> implements AnnotatedElementBuilder {
    private final Binder binder;
    private final Object source;
    private Key<T> key;

    public ExposureBuilder(Binder binder, Object source, Key<T> key) {
        this.binder = binder;
        this.source = source;
        this.key = key;
    }

    protected void checkNotAnnotated() {
        if (key.getAnnotationType() != null) {
            binder.addError(AbstractBindingBuilder.ANNOTATION_ALREADY_SPECIFIED);
        }
    }

    @Override
    public void annotatedWith(Class<? extends Annotation> annotationType) {
        Objects.requireNonNull(annotationType, "annotationType");
        checkNotAnnotated();
        key = Key.get(key.getTypeLiteral(), annotationType);
    }

    @Override
    public void annotatedWith(Annotation annotation) {
        Objects.requireNonNull(annotation, "annotation");
        checkNotAnnotated();
        key = Key.get(key.getTypeLiteral(), annotation);
    }

    public Key<?> getKey() {
        return key;
    }

    public Object getSource() {
        return source;
    }

    @Override
    public String toString() {
        return "AnnotatedElementBuilder";
    }
}