/*
 * 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.brooklyn.core.location;

import static com.google.common.base.Preconditions.checkNotNull;

import java.util.Map;

import org.apache.brooklyn.api.location.Location;
import org.apache.brooklyn.api.location.LocationRegistry;
import org.apache.brooklyn.api.location.LocationResolver;
import org.apache.brooklyn.api.location.LocationSpec;
import org.apache.brooklyn.api.mgmt.ManagementContext;
import org.apache.brooklyn.api.typereg.RegisteredType;
import org.apache.brooklyn.util.text.Strings;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.google.common.annotations.Beta;

/**
 * Given a location spec in the form {@code brooklyn.catalog:<symbolicName>:<version>}, 
 * looks up the catalog to get its definition and creates such a location.
 */
public class CatalogLocationResolver implements LocationResolver {

    private static final Logger log = LoggerFactory.getLogger(CatalogLocationResolver.class);

    public static final String NAME = "brooklyn.catalog";

    private ManagementContext managementContext;

    @Override
    public void init(ManagementContext managementContext) {
        this.managementContext = checkNotNull(managementContext, "managementContext");
    }
    
    @Override
    public boolean isEnabled() {
        return true;
    }
    
    @Override
    public LocationSpec<? extends Location> newLocationSpecFromString(String spec, Map<?, ?> locationFlags, LocationRegistry registry) {
        String id = spec.substring(NAME.length()+1);
        RegisteredType item = managementContext.getTypeRegistry().get(id);
        if (item.isDisabled()) {
            throw new IllegalStateException("Illegal use of disabled catalog item "+item.getSymbolicName()+":"+item.getVersion());
        } else if (item.isDeprecated()) {
            log.warn("Use of deprecated catalog item "+item.getSymbolicName()+":"+item.getVersion());
        }
        
        LocationSpec<?> origLocSpec = managementContext.getTypeRegistry().createSpec(item, null, LocationSpec.class);
        return LocationSpec.create(origLocSpec).configure(locationFlags);
    }

    @Override
    public String getPrefix() {
        return NAME;
    }
    
    /**
     * accepts anything that looks like it will be a YAML catalog item (e.g. starting "brooklyn.catalog:")
     */
    @Override
    public boolean accepts(String spec, LocationRegistry registry) {
        if (BasicLocationRegistry.isResolverPrefixForSpec(this, spec, false)) return true;
        if (registry.getDefinedLocationByName(spec)!=null) return true;
        return false;
    }

    @Beta /** for transitioning away from LocationDefinition */
    public static boolean isLegacyWrappedReference(String spec) {
        if (spec==null) return false;
        if (spec.startsWith(NAME+":")) return true;
        return false;
    }
    @Beta /** for transitioning away from LocationDefinition */
    public static String createLegacyWrappedReference(String id) {
        return NAME + ":" + id;
    }
    @Beta /** for transitioning away from LocationDefinition */
    public static String unwrapLegacyWrappedReference(String id) {
        return Strings.removeFromStart(id, NAME+":");
    }
}
