/*
 * Copyright (c) 2013 Cisco Systems, Inc. and others.  All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v1.0 which accompanies this distribution,
 * and is available at http://www.eclipse.org/legal/epl-v10.html
 */

package org.opendaylight.controller.netconf.confignetconfconnector.osgi;

import java.util.Collection;
import java.util.Collections;
import java.util.Map;
import java.util.Set;

import org.opendaylight.controller.config.util.ConfigRegistryJMXClient;
import org.opendaylight.controller.config.yang.store.api.YangStoreException;
import org.opendaylight.controller.config.yang.store.api.YangStoreService;
import org.opendaylight.controller.config.yang.store.api.YangStoreSnapshot;
import org.opendaylight.controller.netconf.confignetconfconnector.transactions.TransactionProvider;
import org.opendaylight.controller.netconf.confignetconfconnector.util.Util;
import org.opendaylight.controller.netconf.mapping.api.Capability;
import org.opendaylight.controller.netconf.mapping.api.NetconfOperation;
import org.opendaylight.controller.netconf.mapping.api.NetconfOperationFilter;
import org.opendaylight.controller.netconf.mapping.api.NetconfOperationService;
import org.opendaylight.yangtools.yang.model.api.Module;

import com.google.common.base.Optional;
import com.google.common.collect.Sets;

/**
 * Manages life cycle of {@link YangStoreSnapshot}.
 */
public class NetconfOperationServiceImpl implements NetconfOperationService {

    private final YangStoreSnapshot yangStoreSnapshot;
    private final NetconfOperationProvider operationProvider;
    private final Set<Capability> capabilities;
    private final TransactionProvider transactionProvider;

    public NetconfOperationServiceImpl(YangStoreService yangStoreService, ConfigRegistryJMXClient jmxClient,
            String netconfSessionIdForReporting) throws YangStoreException {

        yangStoreSnapshot = yangStoreService.getYangStoreSnapshot();
        transactionProvider = new TransactionProvider(jmxClient, netconfSessionIdForReporting);
        operationProvider = new NetconfOperationProvider(yangStoreSnapshot, jmxClient, transactionProvider,
                netconfSessionIdForReporting);
        capabilities = setupCapabilities(yangStoreSnapshot);
    }

    @Override
    public void close() {
        yangStoreSnapshot.close();
        transactionProvider.close();
    }

    @Override
    public Set<Capability> getCapabilities() {
        return capabilities;
    }

    @Override
    public Set<NetconfOperation> getNetconfOperations() {
        return operationProvider.getOperations();
    }

    @Override
    public Set<NetconfOperationFilter> getFilters() {
        return Collections.emptySet();
    }

    private static Set<Capability> setupCapabilities(YangStoreSnapshot yangStoreSnapshot) {
        Set<Capability> capabilities = Sets.newHashSet();

        capabilities.add(new BasicCapability("urn:ietf:params:netconf:capability:candidate:1.0"));
        capabilities.add(new BasicCapability("urn:ietf:params:netconf:capability:rollback-on-error:1.0"));
        capabilities.add(new BasicCapability("urn:ietf:params:netconf:capability:operations:1.0"));
        capabilities.add(new BasicCapability("urn:ietf:params:netconf:capability:operations:1.1"));
        capabilities
                .add(new BasicCapability(
                        "urn:ietf:params:xml:ns:yang:ietf-netconf-monitoring?module=ietf-netconf-monitoring&amp;revision=2010-10-04"));

        final Collection<Map.Entry<Module, String>> modulesAndContents = yangStoreSnapshot.getModuleMap().values();
        for (Map.Entry<Module, String> moduleAndContent : modulesAndContents) {
            capabilities.add(new YangStoreCapability(moduleAndContent));
        }

        return capabilities;
    }

    private static class BasicCapability implements Capability {

        private final String capability;

        private BasicCapability(String capability) {
            this.capability = capability;
        }

        @Override
        public String getCapabilityUri() {
            return capability;
        }

        @Override
        public Optional<String> getModuleName() {
            return Optional.absent();
        }

        @Override
        public Optional<String> getRevision() {
            return Optional.absent();
        }

        @Override
        public Optional<String> getCapabilitySchema() {
            return Optional.absent();
        }
    }

    private static class YangStoreCapability extends BasicCapability {

        private final String content;
        private final String revision;
        private final String moduleName;

        public YangStoreCapability(Map.Entry<Module, String> moduleAndContent) {
            super(getAsString(moduleAndContent.getKey()));
            this.content = moduleAndContent.getValue();
            Module module = moduleAndContent.getKey();
            this.moduleName = module.getName();
            this.revision = Util.writeDate(module.getRevision());
        }

        @Override
        public Optional<String> getCapabilitySchema() {
            return Optional.of(content);
        }

        private static String getAsString(Module module) {
            final StringBuffer capabilityContent = new StringBuffer();
            capabilityContent.append(module.getNamespace());
            capabilityContent.append("?module=");
            capabilityContent.append(module.getName());
            capabilityContent.append("&revision=");
            capabilityContent.append(Util.writeDate(module.getRevision()));
            return capabilityContent.toString();
        }

        @Override
        public Optional<String> getModuleName() {
            return Optional.of(moduleName);
        }

        @Override
        public Optional<String> getRevision() {
            return Optional.of(revision);
        }
    }
}