// **********************************************************************
//
// Copyright (c) 2003-2007 ZeroC, Inc. All rights reserved.
//
// This copy of Ice is licensed to you under the terms described in the
// ICE_LICENSE file included in this distribution.
//
// **********************************************************************

#include <Ice/Communicator.h>
#include <Ice/LocalException.h>
#include <Ice/LoggerUtil.h>
#include <IceGrid/ReplicaCache.h>
#include <IceGrid/ReplicaSessionI.h>
#include <IceGrid/Topics.h>

using namespace std;
using namespace IceGrid;

ReplicaCache::ReplicaCache(const Ice::CommunicatorPtr& communicator, const IceStorm::TopicManagerPrx& topicManager) :
    _communicator(communicator)
{
    IceStorm::TopicPrx t;
    try
    {
	t = topicManager->create("ReplicaObserverTopic");
    }
    catch(const IceStorm::TopicExists&)
    {
	t = topicManager->retrieve("ReplicaObserverTopic");
    }

    const_cast<IceStorm::TopicPrx&>(_topic) = IceStorm::TopicPrx::uncheckedCast(t->ice_collocationOptimized(true));
    const_cast<ReplicaObserverPrx&>(_observers) = ReplicaObserverPrx::uncheckedCast(_topic->getPublisher());
}

ReplicaEntryPtr
ReplicaCache::add(const string& name, const ReplicaSessionIPtr& session)
{
    Lock sync(*this);
    
    ReplicaEntryPtr entry;
    while(entry = getImpl(name))
    {
	ReplicaSessionIPtr session = entry->getSession();
	if(session->isDestroyed())
	{
	    wait(); // Wait for the session to be removed.
	}
	else
	{
	    //
	    // Check if the replica is still reachable, if not, we
	    // destroy its session.
	    //
	    sync.release();
	    try
	    {
		session->getInternalRegistry()->ice_ping();
		throw ReplicaActiveException();
	    }
	    catch(const Ice::LocalException&)
	    {
		try
		{
		    session->destroy();
		}
		catch(const Ice::LocalException&)
		{
		}
	    }
	    sync.acquire();
	}
    }
    
    if(_traceLevels && _traceLevels->replica > 0)
    {
	Ice::Trace out(_traceLevels->logger, _traceLevels->replicaCat);
	out << "replica `" << name << "' up";
    }
    
    try
    {
	_observers->replicaAdded(session->getInternalRegistry());
    }
    catch(const Ice::ConnectionRefusedException&)
    {
	// Expected if the replica is being shutdown.
    }
    catch(const Ice::LocalException& ex)
    {
	TraceLevelsPtr traceLevels = getTraceLevels();
	if(traceLevels)
	{
	    Ice::Warning out(traceLevels->logger);
	    out << "unexpected exception while publishing `replicaAdded' update:\n" << ex;    
	}
    }

    return addImpl(name, new ReplicaEntry(name, session));
}

ReplicaEntryPtr
ReplicaCache::remove(const string& name, bool shutdown)
{
    Lock sync(*this);

    ReplicaEntryPtr entry = getImpl(name);
    assert(entry);
    removeImpl(name);
    notifyAll();
    
    if(_traceLevels && _traceLevels->replica > 0)
    {
	Ice::Trace out(_traceLevels->logger, _traceLevels->replicaCat);
	out << "replica `" << name << "' down";
    }

    if(!shutdown)
    {
	try
	{
	    _observers->replicaRemoved(entry->getProxy());
	}
	catch(const Ice::ConnectionRefusedException&)
	{
	    // Expected if the replica is being shutdown.
	}
	catch(const Ice::LocalException& ex)
	{
	    TraceLevelsPtr traceLevels = getTraceLevels();
	    if(traceLevels)
	    {
		Ice::Warning out(traceLevels->logger);
		out << "unexpected exception while publishing `replicaRemoved' update:\n" << ex;    
	    }
	}
    }
    
    return entry;
}

ReplicaEntryPtr
ReplicaCache::get(const string& name) const
{
    Lock sync(*this);
    ReplicaEntryPtr entry = getImpl(name);
    if(!entry)
    {
	RegistryNotExistException ex;
	ex.name = name;
	throw ex;
    }
    return entry;
}

void
ReplicaCache::subscribe(const ReplicaObserverPrx& observer)
{
    try
    {
	Lock sync(*this);
	InternalRegistryPrxSeq replicas;
	for(map<string, ReplicaEntryPtr>::const_iterator p = _entries.begin(); p != _entries.end(); ++p)
	{
	    replicas.push_back(p->second->getProxy());
	}
	
	IceStorm::QoS qos;
	qos["reliability"] = "twoway ordered";
	Ice::ObjectPrx publisher = _topic->subscribeAndGetPublisher(qos, observer);
	ReplicaObserverPrx::uncheckedCast(publisher)->replicaInit(replicas);
    }
    catch(const Ice::ConnectionRefusedException&)
    {
	// The replica is being shutdown.
    }
    catch(const Ice::LocalException& ex)
    {
	TraceLevelsPtr traceLevels = getTraceLevels();
	if(traceLevels)
	{
	    Ice::Warning out(traceLevels->logger);
	    out << "unexpected exception while subscribing observer from replica observer topic:\n" << ex;    
	}
    }
}

void
ReplicaCache::unsubscribe(const ReplicaObserverPrx& observer)
{
    try
    {
	_topic->unsubscribe(observer);
    }
    catch(const Ice::ConnectionRefusedException&)
    {
	// The replica is being shutdown.
    }
    catch(const Ice::LocalException& ex)
    {
	TraceLevelsPtr traceLevels = getTraceLevels();
	if(traceLevels)
	{
	    Ice::Warning out(traceLevels->logger);
	    out << "unexpected exception while unsubscribing observer from replica observer topic:\n" << ex;    
	}
    }
}

Ice::ObjectPrx
ReplicaCache::getEndpoints(const string& name, const Ice::ObjectPrx& proxy) const
{
    Ice::EndpointSeq endpoints;

    if(proxy)
    {
	Ice::EndpointSeq endpts = proxy->ice_getEndpoints();
	endpoints.insert(endpoints.end(), endpts.begin(), endpts.end());
    }

    Lock sync(*this);
    for(map<string, ReplicaEntryPtr>::const_iterator p = _entries.begin(); p != _entries.end(); ++p)
    {
	Ice::ObjectPrx prx = p->second->getSession()->getEndpoint(name);
	if(prx)
	{
	    Ice::EndpointSeq endpts = prx->ice_getEndpoints();
	    endpoints.insert(endpoints.end(), endpts.begin(), endpts.end());
	}
    }

    return _communicator->stringToProxy("dummy")->ice_endpoints(endpoints);
}

void
ReplicaCache::setInternalRegistry(const InternalRegistryPrx& proxy)
{
    // 
    // Setup this replica internal registry proxy.
    //
    _self = proxy;
}

InternalRegistryPrx
ReplicaCache::getInternalRegistry() const
{
    // 
    // This replica internal registry proxy.
    //
    return _self;
}

ReplicaEntry::ReplicaEntry(const std::string& name, const ReplicaSessionIPtr& session) : 
    _name(name),
    _session(session)
{
}

ReplicaEntry::~ReplicaEntry()
{
}

const ReplicaSessionIPtr&
ReplicaEntry::getSession() const
{ 
    return _session;
}

InternalReplicaInfoPtr
ReplicaEntry::getInfo() const
{
    return _session->getInfo();
}

InternalRegistryPrx
ReplicaEntry::getProxy() const
{
    return _session->getInternalRegistry();
}