/*
 *  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.isis.applib;

import java.io.InputStream;
import java.util.Map;
import java.util.Properties;

public final class PropertyResource {
    private final Class<?> resourceContext;
    private final String resourceName;

    /**
     * @since 2.0.0-M2
     */
    public static PropertyResource ofClassContext(final Class<?> resourceContext, final String resourceName) {
        return new PropertyResource(resourceContext, resourceName);
    }
    
    PropertyResource(final Class<?> resourceContext, final String resourceName) {
        this.resourceContext = resourceContext;
        this.resourceName = resourceName;
    }

    /**
     * @since 2.0.0-M2
     */
    public Class<?> getResourceContext() {
        return resourceContext;
    }

    /**
     * @since 2.0.0-M2
     */
    public String getResourceName() {
        return resourceName;
    }

    void loadPropsInto(final Map<String, String> props) {
        
        final Properties properties = new Properties();
        try {
            try (final InputStream stream = resourceContext.getResourceAsStream(resourceName)) {
                properties.load(stream);
                for (Object key : properties.keySet()) {
                    final Object value = properties.get(key);
                    if (key instanceof String && value instanceof String) {
                        props.put((String) key, (String) value);
                    }
                }
            }
        } catch (Exception e) {
            throw new RuntimeException(
                    String.format("Failed to load '%s' file relative to %s", getResourceName(), getResourceContext().getName()), e);
        }
    }
}
