/**
 *    Copyright (C) 2014 MongoDB Inc.
 *
 *    This program is free software: you can redistribute it and/or  modify
 *    it under the terms of the GNU Affero General Public License, version 3,
 *    as published by the Free Software Foundation.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU Affero General Public License for more details.
 *
 *    You should have received a copy of the GNU Affero General Public License
 *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 *    As a special exception, the copyright holders give permission to link the
 *    code of portions of this program with the OpenSSL library under certain
 *    conditions as described in each individual source file and distribute
 *    linked combinations including the program with the OpenSSL library. You
 *    must comply with the GNU Affero General Public License in all respects for
 *    all of the code used other than as permitted herein. If you modify file(s)
 *    with this exception, you may extend this exception to your version of the
 *    file(s), but you are not obligated to do so. If you do not wish to do so,
 *    delete this exception statement from your version. If you delete this
 *    exception statement from all source files in the program, then also delete
 *    it in the license file.
 */

#include "mongo/db/global_environment_d.h"

#include <set>

#include "mongo/bson/util/atomic_int.h"
#include "mongo/db/client.h"
#include "mongo/db/curop.h"
#include "mongo/db/operation_context_impl.h"
#include "mongo/db/storage/storage_engine.h"
#include "mongo/scripting/engine.h"

namespace mongo {

    GlobalEnvironmentMongoD::GlobalEnvironmentMongoD()
        : _globalKill(false),
          _registeredOpContextsMutex("RegisteredOpContextsMutex") {

    }

    GlobalEnvironmentMongoD::~GlobalEnvironmentMongoD() {
        if (!_registeredOpContexts.empty()) {
            warning() << "Terminating with outstanding operation contexts." << endl;
        }
    }

    StorageEngine* GlobalEnvironmentMongoD::getGlobalStorageEngine() {
        return globalStorageEngine;
    }

    namespace {
        void interruptJs(AtomicUInt* op) {
            if (!globalScriptEngine) {
                return;
            }

            if (!op) {
                globalScriptEngine->interruptAll();
            }
            else {
                globalScriptEngine->interrupt(*op);
            }
        }
    }  // namespace

    void GlobalEnvironmentMongoD::setKillAllOperations() {
        _globalKill = true;
        interruptJs(0);
    }

    bool GlobalEnvironmentMongoD::getKillAllOperations() {
        return _globalKill;
    }

    bool GlobalEnvironmentMongoD::killOperation(AtomicUInt opId) {
        scoped_lock clientLock(Client::clientsMutex);
        bool found = false;

        // XXX clean up
        {
            for( set< Client* >::const_iterator j = Client::clients.begin();
                 !found && j != Client::clients.end();
                 ++j ) {

                for( CurOp *k = ( *j )->curop(); !found && k; k = k->parent() ) {
                    if ( k->opNum() != opId )
                        continue;

                    k->kill();
                    for( CurOp *l = ( *j )->curop(); l; l = l->parent() ) {
                        l->kill();
                    }

                    found = true;
                }
            }
        }
        if ( found ) {
            interruptJs( &opId );
        }
        return found;
    }

    void GlobalEnvironmentMongoD::unsetKillAllOperations() {
        _globalKill = false;
    }

    void GlobalEnvironmentMongoD::registerOperationContext(OperationContext* txn) {
        scoped_lock lock(_registeredOpContextsMutex);

        // It is an error to register twice
        pair<OperationContextSet::const_iterator, bool> inserted 
                    = _registeredOpContexts.insert(txn);
        invariant(inserted.second);
    }

    void GlobalEnvironmentMongoD::unregisterOperationContext(OperationContext* txn) {
        scoped_lock lock(_registeredOpContextsMutex);

        // It is an error to unregister twice or to unregister something that's not been registered
        OperationContextSet::const_iterator it = _registeredOpContexts.find(txn);
        invariant(it != _registeredOpContexts.end());

        _registeredOpContexts.erase(it);
    }

    void GlobalEnvironmentMongoD::forEachOperationContext(ProcessOperationContext* procOpCtx) {
        scoped_lock lock(_registeredOpContextsMutex);

        OperationContextSet::iterator it;
        for (it = _registeredOpContexts.begin(); it != _registeredOpContexts.end(); it++) {
            procOpCtx->processOpContext(*it);
        }
    }

    OperationContext* GlobalEnvironmentMongoD::newOpCtx() {
        return new OperationContextImpl();
    }

}  // namespace mongo