/*
 * 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.camel.spring.boot.util;

import java.util.Collection;
import org.springframework.boot.context.properties.bind.Bindable;
import org.springframework.boot.context.properties.bind.Binder;
import org.springframework.context.ApplicationContext;
import org.springframework.core.env.Environment;

public final class HierarchicalPropertiesEvaluator {

    private HierarchicalPropertiesEvaluator() {
    }

    /**
     * Determine the value of the "enabled" flag for a hierarchy of properties.
     *
     * @param applicationContext
     *            the spring {@link ApplicationContext}
     * @param prefixes
     *            an ordered list of prefixed (less restrictive to more restrictive)
     *
     * @return the value of the key `enabled` for most restrictive prefix
     */
    public static boolean evaluate(ApplicationContext applicationContext, String... prefixes) {
        return evaluate(applicationContext.getEnvironment(), prefixes);
    }

    /**
     * Determine the value of the "enabled" flag for a hierarchy of properties.
     *
     * @param environment
     *            the environment
     * @param prefixes
     *            an ordered list of prefixed (less restrictive to more restrictive)
     *
     * @return the value of the key `enabled` for most restrictive prefix
     */
    public static boolean evaluate(Environment environment, String... prefixes) {
        boolean answer = true;

        // Loop over all the prefixes to find out the value of the key `enabled`
        // for the most restrictive prefix.
        for (String prefix : prefixes) {
            // evaluate the value of the current prefix using the parent one
            // as default value so if the enabled property is not set, the parent
            // one is used.
            answer = isEnabled(environment, prefix, answer);
        }

        return answer;
    }

    /**
     * Determine the value of the "enabled" flag for a hierarchy of properties.
     *
     * @param environment
     *            the environment
     * @param prefixes
     *            an ordered list of prefixed (less restrictive to more restrictive)
     *
     * @return the value of the key `enabled` for most restrictive prefix
     */
    public static boolean evaluate(Environment environment, Collection<String> prefixes) {
        boolean answer = true;

        // Loop over all the prefixes to find out the value of the key `enabled`
        // for the most restrictive prefix.
        for (String prefix : prefixes) {
            // evaluate the value of the current prefix using the parent one
            // as default value so if the enabled property is not set, the parent
            // one is used.
            answer = isEnabled(environment, prefix, answer);
        }

        return answer;
    }

    private static boolean isEnabled(Environment environment, String prefix, boolean defaultValue) {
        String property = prefix.endsWith(".") ? prefix + "enabled" : prefix + ".enabled";
        Binder binder = Binder.get(environment);
        return binder.bind(property, Bindable.of(Boolean.class)).orElse(defaultValue);
    }
}
