/**
 * Copyright 2011-2015 John Ericksen
 *
 * 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.androidtransfuse.adapter.element;

import com.google.common.base.Function;
import com.google.common.collect.FluentIterable;
import com.google.common.collect.ImmutableSet;
import org.androidtransfuse.adapter.ASTAnnotation;
import org.androidtransfuse.adapter.ASTType;
import org.apache.commons.lang.builder.HashCodeBuilder;

import javax.inject.Inject;
import javax.lang.model.element.AnnotationMirror;
import javax.lang.model.element.AnnotationValue;
import javax.lang.model.element.ExecutableElement;
import java.util.HashMap;
import java.util.Map;

/**
 * Element specific AST Annotation
 *
 * @author John Ericksen
 */
public class ASTElementAnnotation implements ASTAnnotation {

    private final AnnotationMirror annotationMirror;
    private final ASTType type;
    private final ElementConverterFactory elementConverterFactory;

    @Inject
    public ASTElementAnnotation(/*@Assisted*/ AnnotationMirror annotationMirror,
                                /*@Assisted*/ ASTType type,
                                ElementConverterFactory elementConverterFactory) {
        this.annotationMirror = annotationMirror;
        this.elementConverterFactory = elementConverterFactory;
        this.type = type;
    }

    @Override
    public ImmutableSet<String> getPropertyNames() {
        return FluentIterable.from(annotationMirror.getElementValues().keySet())
                .transform(new ExtractElementName())
                .toSet();
    }

    public AnnotationMirror getAnnotationMirror() {
        return annotationMirror;
    }

    private static final class ExtractElementName implements Function<ExecutableElement, String> {
        @Override
        public String apply(ExecutableElement property) {
            return property.getSimpleName().toString();
        }
    }

    @Override
    public <T> T getProperty(String value, Class<T> type) {
        for (Map.Entry<? extends ExecutableElement, ? extends AnnotationValue> entry : annotationMirror.getElementValues().entrySet()) {
            if (value.equals(entry.getKey().getSimpleName().toString())) {
                return entry.getValue().accept(elementConverterFactory.buildAnnotationValueConverter(type), null);
            }
        }
        return null;
    }

    @Override
    public ASTType getASTType() {
        return type;
    }

    @Override
    public String toString() {
        return "ASTElementAnnotation{" +
                "type=" + type +
                '}';
    }

    @Override
    public boolean equals(Object o) {
        if (this == o){
            return true;
        }
        if (!(o instanceof ASTAnnotation)){
            return false;
        }

        ASTAnnotation that = (ASTAnnotation) o;

        if(!type.equals(that.getASTType())){
            return false;
        }

        Map<String, Object> thisProperties = new HashMap<String, Object>();
        Map<String, Object> thatProperties = new HashMap<String, Object>();

        for (String property : getPropertyNames()) {
            thisProperties.put(property, this.getProperty(property, Object.class));
            thatProperties.put(property, that.getProperty(property, Object.class));
        }

        return thisProperties.equals(thatProperties);
    }

    @Override
    public int hashCode() {
        return new HashCodeBuilder().append(type).hashCode();
    }
}