/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.apache.maven.configuration.internal;

import java.io.File;
import java.util.Objects;

import org.apache.maven.configuration.BeanConfigurationException;
import org.apache.maven.configuration.BeanConfigurationPathTranslator;
import org.apache.maven.configuration.BeanConfigurationRequest;
import org.apache.maven.configuration.BeanConfigurationValuePreprocessor;
import org.apache.maven.configuration.BeanConfigurator;
import org.codehaus.plexus.component.annotations.Component;
import org.codehaus.plexus.component.configurator.ComponentConfigurationException;
import org.codehaus.plexus.component.configurator.converters.composite.ObjectWithFieldsConverter;
import org.codehaus.plexus.component.configurator.converters.lookup.ConverterLookup;
import org.codehaus.plexus.component.configurator.converters.lookup.DefaultConverterLookup;
import org.codehaus.plexus.component.configurator.expression.ExpressionEvaluationException;
import org.codehaus.plexus.component.configurator.expression.TypeAwareExpressionEvaluator;
import org.codehaus.plexus.configuration.PlexusConfiguration;
import org.codehaus.plexus.configuration.xml.XmlPlexusConfiguration;
import org.codehaus.plexus.util.xml.Xpp3Dom;

/**
 * <strong>Warning:</strong> This is an internal class that is only public for technical reasons, it is not part of the
 * public API. In particular, this class can be changed or deleted without prior notice.
 *
 * @author Benjamin Bentmann
 */
@Component(role = BeanConfigurator.class)
public class DefaultBeanConfigurator implements BeanConfigurator {

    private final ConverterLookup converterLookup = new DefaultConverterLookup();

    public void configureBean(BeanConfigurationRequest request) throws BeanConfigurationException {
        Objects.requireNonNull(request, "request cannot be null");
        Objects.requireNonNull(request.getBean(), "request.bean cannot be null");

        Object configuration = request.getConfiguration();
        if (configuration == null) {
            return;
        }

        PlexusConfiguration plexusConfig;
        if (configuration instanceof PlexusConfiguration) {
            plexusConfig = (PlexusConfiguration) configuration;
        } else if (configuration instanceof Xpp3Dom) {
            plexusConfig = new XmlPlexusConfiguration((Xpp3Dom) configuration);
        } else {
            throw new BeanConfigurationException("unsupported bean configuration source ("
                    + configuration.getClass().getName() + ")");
        }

        if (request.getConfigurationElement() != null) {
            plexusConfig = plexusConfig.getChild(request.getConfigurationElement());
        }

        ClassLoader classLoader = request.getClassLoader();
        if (classLoader == null) {
            classLoader = request.getBean().getClass().getClassLoader();
        }

        BeanExpressionEvaluator evaluator = new BeanExpressionEvaluator(request);

        ObjectWithFieldsConverter converter = new ObjectWithFieldsConverter();

        try {
            converter.processConfiguration(converterLookup, request.getBean(), classLoader, plexusConfig, evaluator);
        } catch (ComponentConfigurationException e) {
            throw new BeanConfigurationException(e.getMessage(), e);
        }
    }

    static class BeanExpressionEvaluator implements TypeAwareExpressionEvaluator {

        private final BeanConfigurationValuePreprocessor preprocessor;

        private final BeanConfigurationPathTranslator translator;

        BeanExpressionEvaluator(BeanConfigurationRequest request) {
            preprocessor = request.getValuePreprocessor();
            translator = request.getPathTranslator();
        }

        public Object evaluate(String expression, Class<?> type) throws ExpressionEvaluationException {
            if (preprocessor != null) {
                try {
                    return preprocessor.preprocessValue(expression, type);
                } catch (BeanConfigurationException e) {
                    throw new ExpressionEvaluationException(e.getMessage(), e);
                }
            }
            return expression;
        }

        public Object evaluate(String expression) throws ExpressionEvaluationException {
            return evaluate(expression, null);
        }

        public File alignToBaseDirectory(File file) {
            if (translator != null) {
                return translator.translatePath(file);
            }
            return file;
        }
    }
}
