/*
 * Copyright 2004, 2005, 2006 Acegi Technology Pty Limited
 *
 * 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
 *
 *      https://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.springframework.security.access.annotation;

import java.lang.annotation.Annotation;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;

import org.springframework.core.GenericTypeResolver;
import org.springframework.core.annotation.AnnotationUtils;
import org.springframework.security.access.ConfigAttribute;
import org.springframework.security.access.SecurityConfig;
import org.springframework.security.access.method.AbstractFallbackMethodSecurityMetadataSource;
import org.springframework.util.Assert;

/**
 * Sources method security metadata from Spring Security's {@link Secured} annotation.
 * <p>
 * Can also be used with custom security annotations by injecting an
 * {@link AnnotationMetadataExtractor}. The annotation type will then be obtained from the
 * generic parameter type supplied to this interface
 *
 * @author Ben Alex
 * @author Luke Taylor
 * @deprecated Use
 * {@link org.springframework.security.authorization.method.AuthorizationManagerBeforeMethodInterceptor#secured}
 */
@Deprecated
@SuppressWarnings({ "unchecked" })
public class SecuredAnnotationSecurityMetadataSource extends AbstractFallbackMethodSecurityMetadataSource {

	private AnnotationMetadataExtractor annotationExtractor;

	private Class<? extends Annotation> annotationType;

	public SecuredAnnotationSecurityMetadataSource() {
		this(new SecuredAnnotationMetadataExtractor());
	}

	public SecuredAnnotationSecurityMetadataSource(AnnotationMetadataExtractor annotationMetadataExtractor) {
		Assert.notNull(annotationMetadataExtractor, "annotationMetadataExtractor cannot be null");
		this.annotationExtractor = annotationMetadataExtractor;
		this.annotationType = (Class<? extends Annotation>) GenericTypeResolver
				.resolveTypeArgument(this.annotationExtractor.getClass(), AnnotationMetadataExtractor.class);
		Assert.notNull(this.annotationType, () -> this.annotationExtractor.getClass().getName()
				+ " must supply a generic parameter for AnnotationMetadataExtractor");
	}

	@Override
	protected Collection<ConfigAttribute> findAttributes(Class<?> clazz) {
		return processAnnotation(AnnotationUtils.findAnnotation(clazz, this.annotationType));
	}

	@Override
	protected Collection<ConfigAttribute> findAttributes(Method method, Class<?> targetClass) {
		return processAnnotation(AnnotationUtils.findAnnotation(method, this.annotationType));
	}

	@Override
	public Collection<ConfigAttribute> getAllConfigAttributes() {
		return null;
	}

	private Collection<ConfigAttribute> processAnnotation(Annotation annotation) {
		return (annotation != null) ? this.annotationExtractor.extractAttributes(annotation) : null;
	}

	static class SecuredAnnotationMetadataExtractor implements AnnotationMetadataExtractor<Secured> {

		@Override
		public Collection<ConfigAttribute> extractAttributes(Secured secured) {
			String[] attributeTokens = secured.value();
			List<ConfigAttribute> attributes = new ArrayList<>(attributeTokens.length);
			for (String token : attributeTokens) {
				attributes.add(new SecurityConfig(token));
			}
			return attributes;
		}

	}

}
