/*
 * Copyright (c) 2016, 2017 Ericsson India Global Services Pvt Ltd. 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.ovsdb.hwvtepsouthbound;

import org.opendaylight.ovsdb.hwvtepsouthbound.transact.DependencyQueue;
import org.opendaylight.ovsdb.hwvtepsouthbound.transact.DependentJob;
import org.opendaylight.ovsdb.hwvtepsouthbound.transact.TransactCommand;
import org.opendaylight.ovsdb.lib.notation.UUID;
import org.opendaylight.ovsdb.schema.hardwarevtep.LogicalSwitch;
import org.opendaylight.ovsdb.schema.hardwarevtep.PhysicalLocator;
import org.opendaylight.ovsdb.schema.hardwarevtep.PhysicalSwitch;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.ovsdb.hwvtep.rev150901.hwvtep.global.attributes.LogicalSwitches;
import org.opendaylight.yang.gen.v1.urn.tbd.params.xml.ns.yang.network.topology.rev131021.network.topology.topology.node.TerminationPoint;
import org.opendaylight.yangtools.yang.binding.Identifiable;
import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;

/*
 * HwvtepDeviceInfo is used to store some of the table entries received
 * in updates from a Hwvtep device. There will be one instance of this per
 * Hwvtep device connected. Table entries are stored in a map keyed by
 * uuids of respective rows.
 *
 * Purpose of this class is to provide data present in tables which
 * were updated in a previous transaction and are not available in
 * current updatedRows. This allows us to handle updates for Tables
 * which reference other tables and need information in those tables
 * to add data to Operational data store.
 *
 * e.g. Mac-entries in data store use logical-switch-ref as one of the
 * keys. Mac-entry updates from switch rarely contain Logical_Switch
 * table entries. To add mac-entries we need table entries from
 * Logical_Switch table which were created in an earlier update.
 *
 */
public class HwvtepDeviceInfo {

    private static final Logger LOG = LoggerFactory.getLogger(HwvtepDeviceInfo.class);

    public enum DeviceDataStatus {
        IN_TRANSIT,
        UNAVAILABLE,
        AVAILABLE
    }

    public static class DeviceData {
        private final InstanceIdentifier key;
        private final UUID uuid;
        private final Object data;
        private final DeviceDataStatus status;

        DeviceData(InstanceIdentifier key, UUID uuid, Object data, DeviceDataStatus status) {
            this.data = data;
            this.key = key;
            this.status = status;
            this.uuid = uuid;
        }

        public Object getData() {
            return data;
        }

        public DeviceDataStatus getStatus() {
            return status;
        }

        public UUID getUuid() {
            return uuid;
        }
    }

    //TODO remove this
    private Map<UUID, LogicalSwitch> logicalSwitches = null;
    private Map<UUID, PhysicalSwitch> physicalSwitches = null;
    private Map<UUID, PhysicalLocator> physicalLocators = null;
    private Map<UUID, UUID> mapTunnelToPhysicalSwitch = null;

    private HwvtepConnectionInstance connectionInstance;

    private Map<Class<? extends Identifiable>, Map<InstanceIdentifier, DeviceData>> configKeyVsData = new ConcurrentHashMap<>();
    private Map<Class<? extends Identifiable>, Map<InstanceIdentifier, DeviceData>> opKeyVsData = new ConcurrentHashMap<>();
    private Map<Class<? extends Identifiable>, Map<UUID, Object>> uuidVsData = new ConcurrentHashMap<>();
    private DependencyQueue dependencyQueue;

    public HwvtepDeviceInfo(HwvtepConnectionInstance hwvtepConnectionInstance) {
        this.connectionInstance = hwvtepConnectionInstance;
        this.logicalSwitches = new HashMap<>();
        this.physicalSwitches = new HashMap<>();
        this.physicalLocators = new HashMap<>();
        this.mapTunnelToPhysicalSwitch = new HashMap<>();
        this.dependencyQueue = new DependencyQueue(this);
    }

    public LogicalSwitch getLogicalSwitch(UUID uuid) {
        return (LogicalSwitch) getDeviceOperData(LogicalSwitches.class, uuid);
    }

    public Map<UUID, LogicalSwitch> getLogicalSwitches() {
        Map<UUID, Object> switches = uuidVsData.get(LogicalSwitches.class);
        Map<UUID, LogicalSwitch> result = new HashMap<>();
        if (switches != null) {
            for (Map.Entry<UUID, Object> entry : switches.entrySet()) {
                result.put(entry.getKey(), (LogicalSwitch) entry.getValue());
            }
        }
        return result;
    }

    public void putPhysicalSwitch(UUID uuid, PhysicalSwitch pSwitch) {
        physicalSwitches.put(uuid, pSwitch);
    }

    public PhysicalSwitch getPhysicalSwitch(UUID uuid) {
        return physicalSwitches.get(uuid);
    }

    public PhysicalSwitch removePhysicalSwitch(UUID uuid) {
        return physicalSwitches.remove(uuid);
    }

    public Map<UUID, PhysicalSwitch> getPhysicalSwitches() {
        return physicalSwitches;
    }

    public PhysicalLocator getPhysicalLocator(UUID uuid) {
        return (PhysicalLocator) getDeviceOperData(TerminationPoint.class, uuid);
    }

    public Map<UUID, PhysicalLocator> getPhysicalLocators() {
        Map<UUID, Object> locators = uuidVsData.get(LogicalSwitches.class);
        Map<UUID, PhysicalLocator> result = new HashMap<>();
        if (locators != null) {
            for (Map.Entry<UUID, Object> entry : locators.entrySet()) {
                result.put(entry.getKey(), (PhysicalLocator) entry.getValue());
            }
        }
        return result;
    }

    public void putPhysicalSwitchForTunnel(UUID uuid, UUID psUUID) {
        mapTunnelToPhysicalSwitch.put(uuid, psUUID);
    }

    public PhysicalSwitch getPhysicalSwitchForTunnel(UUID uuid) {
        return physicalSwitches.get(mapTunnelToPhysicalSwitch.get(uuid));
    }

    public void removePhysicalSwitchForTunnel(UUID uuid) {
        mapTunnelToPhysicalSwitch.remove(uuid);
    }

    public Map<UUID, UUID> getPhysicalSwitchesForTunnels() {
        return mapTunnelToPhysicalSwitch;
    }

    public boolean isKeyInTransit(Class<? extends Identifiable> cls, InstanceIdentifier key) {
        DeviceData deviceData = HwvtepSouthboundUtil.getData(opKeyVsData, cls, key);
        return deviceData != null && DeviceDataStatus.IN_TRANSIT == deviceData.status;
    }

    public boolean isConfigDataAvailable(Class<? extends Identifiable> cls, InstanceIdentifier key) {
        return HwvtepSouthboundUtil.getData(configKeyVsData, cls, key) != null;
    }

    public void updateConfigData(Class<? extends Identifiable> cls, InstanceIdentifier key, Object data) {
        HwvtepSouthboundUtil.updateData(configKeyVsData, cls, key,
                new DeviceData(key, null, data, DeviceDataStatus.AVAILABLE));
    }

    public Object getConfigData(Class<? extends Identifiable> cls, InstanceIdentifier key) {
        return HwvtepSouthboundUtil.getData(configKeyVsData, cls, key);
    }

    public void clearConfigData(Class<? extends Identifiable> cls, InstanceIdentifier key) {
        HwvtepSouthboundUtil.clearData(configKeyVsData, cls, key);
    }

    public void markKeyAsInTransit(Class<? extends Identifiable> cls, InstanceIdentifier key) {
        LOG.debug("Marking device data as intransit {}", key);
        DeviceData deviceData = getDeviceOperData(cls, key);
        UUID uuid = null;
        Object data = null;
        if (deviceData != null) {
            uuid = deviceData.getUuid();
            data = deviceData.getData();
        }
        HwvtepSouthboundUtil.updateData(opKeyVsData, cls, key,
                new DeviceData(key, uuid, data, DeviceDataStatus.IN_TRANSIT));
    }

    public void updateDeviceOperData(Class<? extends Identifiable> cls, InstanceIdentifier key, UUID uuid, Object data) {
        LOG.debug("Updating device data {}", key);
        HwvtepSouthboundUtil.updateData(opKeyVsData, cls, key,
                new DeviceData(key, uuid, data, DeviceDataStatus.AVAILABLE));
        HwvtepSouthboundUtil.updateData(uuidVsData, cls, uuid, data);
    }

    public void clearDeviceOperData(Class<? extends Identifiable> cls, InstanceIdentifier key) {
        DeviceData deviceData = HwvtepSouthboundUtil.getData(opKeyVsData, cls, key);
        if (deviceData != null && deviceData.uuid != null) {
            HwvtepSouthboundUtil.clearData(uuidVsData, cls, deviceData.uuid);
        }
        HwvtepSouthboundUtil.clearData(opKeyVsData, cls, key);
    }

    public Object getDeviceOperData(Class<? extends Identifiable> cls, UUID uuid) {
        return HwvtepSouthboundUtil.getData(uuidVsData, cls, uuid);
    }

    public DeviceData getDeviceOperData(Class<? extends Identifiable> cls, InstanceIdentifier key) {
        return HwvtepSouthboundUtil.getData(opKeyVsData, cls, key);
    }

    public UUID getUUID(Class<? extends Identifiable> cls, InstanceIdentifier key) {
        DeviceData data = HwvtepSouthboundUtil.getData(opKeyVsData, cls, key);
        if (data != null) {
            return data.uuid;
        }
        return null;
    }

    public <T extends Identifiable> void addJobToQueue(DependentJob<T> job) {
        dependencyQueue.addToQueue(job);
    }

    public void onConfigDataAvailable() {
        dependencyQueue.processReadyJobsFromConfigQueue(connectionInstance);
    }

    public void onOperDataAvailable() {
        dependencyQueue.processReadyJobsFromOpQueue(connectionInstance);
    }

    public void scheduleTransaction(final TransactCommand transactCommand) {
        dependencyQueue.submit(new Runnable() {
            @Override
            public void run() {
                connectionInstance.transact(transactCommand);
            }
        });
    }

    public void clearInTransitData() {
        //TODO restore old data
        for (Map<InstanceIdentifier, DeviceData> map : opKeyVsData.values()) {
            Iterator<Map.Entry<InstanceIdentifier, DeviceData>> iterator = map.entrySet().iterator();
            while ( iterator.hasNext() ) {
                Map.Entry<InstanceIdentifier, DeviceData> entry = iterator.next();
                if (entry.getValue().getStatus() == DeviceDataStatus.IN_TRANSIT) {
                    iterator.remove();
                }
            }
        }
        onOperDataAvailable();
    }
}