// 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 com.cloud.cluster.dao;

import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import java.util.TimeZone;

import javax.ejb.Local;

import org.apache.log4j.Logger;

import com.cloud.cluster.ClusterInvalidSessionException;
import com.cloud.cluster.ManagementServerHost;
import com.cloud.cluster.ManagementServerHost.State;
import com.cloud.cluster.ManagementServerHostVO;
import com.cloud.utils.DateUtil;
import com.cloud.utils.db.DB;
import com.cloud.utils.db.Filter;
import com.cloud.utils.db.GenericDaoBase;
import com.cloud.utils.db.SearchBuilder;
import com.cloud.utils.db.SearchCriteria;
import com.cloud.utils.db.TransactionLegacy;
import com.cloud.utils.exception.CloudRuntimeException;

@Local(value = {ManagementServerHostDao.class})
public class ManagementServerHostDaoImpl extends GenericDaoBase<ManagementServerHostVO, Long> implements ManagementServerHostDao {
    private static final Logger s_logger = Logger.getLogger(ManagementServerHostDaoImpl.class);

    private final SearchBuilder<ManagementServerHostVO> MsIdSearch;
    private final SearchBuilder<ManagementServerHostVO> ActiveSearch;
    private final SearchBuilder<ManagementServerHostVO> InactiveSearch;
    private final SearchBuilder<ManagementServerHostVO> StateSearch;

    @Override
    public void invalidateRunSession(long id, long runid) {
        TransactionLegacy txn = TransactionLegacy.currentTxn();
        PreparedStatement pstmt = null;
        try {
            pstmt = txn.prepareAutoCloseStatement("update mshost set runid=0, state='Down' where id=? and runid=?");
            pstmt.setLong(1, id);
            pstmt.setLong(2, runid);

            pstmt.executeUpdate();
        } catch (SQLException e) {
            throw new CloudRuntimeException("DB exception on " + pstmt.toString(), e);
        }
    }

    @Override
    public ManagementServerHostVO findByMsid(long msid) {
        SearchCriteria<ManagementServerHostVO> sc = MsIdSearch.create();
        sc.setParameters("msid", msid);

        List<ManagementServerHostVO> l = listIncludingRemovedBy(sc);
        if (l != null && l.size() > 0) {
            return l.get(0);
        }

        return null;
    }

    @Override
    @DB
    public void update(long id, long runid, String name, String version, String serviceIP, int servicePort, Date lastUpdate) {
        TransactionLegacy txn = TransactionLegacy.currentTxn();
        PreparedStatement pstmt = null;
        try {
            txn.start();

            pstmt =
                txn.prepareAutoCloseStatement("update mshost set name=?, version=?, service_ip=?, service_port=?, last_update=?, removed=null, alert_count=0, runid=?, state=? where id=?");
            pstmt.setString(1, name);
            pstmt.setString(2, version);
            pstmt.setString(3, serviceIP);
            pstmt.setInt(4, servicePort);
            pstmt.setString(5, DateUtil.getDateDisplayString(TimeZone.getTimeZone("GMT"), lastUpdate));
            pstmt.setLong(6, runid);
            pstmt.setString(7, ManagementServerHost.State.Up.toString());
            pstmt.setLong(8, id);

            pstmt.executeUpdate();
            txn.commit();
        } catch (Exception e) {
            s_logger.warn("Unexpected exception, ", e);
            throw new RuntimeException(e.getMessage(), e);
        }
    }

    @Override
    @DB
    public boolean remove(Long id) {
        TransactionLegacy txn = TransactionLegacy.currentTxn();

        try {
            txn.start();

            ManagementServerHostVO msHost = findById(id);
            msHost.setState(ManagementServerHost.State.Down);
            super.remove(id);

            txn.commit();
            return true;
        } catch (Exception e) {
            s_logger.warn("Unexpected exception, ", e);
            throw new RuntimeException(e.getMessage(), e);
        }
    }

    @Override
    @DB
    public void update(long id, long runid, Date lastUpdate) {
        TransactionLegacy txn = TransactionLegacy.currentTxn();
        PreparedStatement pstmt = null;
        try {
            txn.start();

            pstmt = txn.prepareAutoCloseStatement("update mshost set last_update=?, removed=null, alert_count=0 where id=? and runid=?");
            pstmt.setString(1, DateUtil.getDateDisplayString(TimeZone.getTimeZone("GMT"), lastUpdate));
            pstmt.setLong(2, id);
            pstmt.setLong(3, runid);

            int count = pstmt.executeUpdate();
            txn.commit();

            if (count < 1) {
                throw new CloudRuntimeException("Invalid cluster session detected", new ClusterInvalidSessionException("runid " + runid + " is no longer valid"));
            }
        } catch (Exception e) {
            s_logger.warn("Unexpected exception, ", e);
            throw new RuntimeException(e.getMessage(), e);
        }
    }

    @Override
    public List<ManagementServerHostVO> getActiveList(Date cutTime) {
        SearchCriteria<ManagementServerHostVO> sc = ActiveSearch.create();
        sc.setParameters("lastUpdateTime", cutTime);

        return listIncludingRemovedBy(sc);
    }

    @Override
    public List<ManagementServerHostVO> getInactiveList(Date cutTime) {
        SearchCriteria<ManagementServerHostVO> sc = InactiveSearch.create();
        sc.setParameters("lastUpdateTime", cutTime);

        return listIncludingRemovedBy(sc);
    }

    @Override
    @DB
    public int increaseAlertCount(long id) {
        TransactionLegacy txn = TransactionLegacy.currentTxn();
        PreparedStatement pstmt = null;
        int changedRows = 0;
        try {
            txn.start();

            pstmt = txn.prepareAutoCloseStatement("update mshost set alert_count=alert_count+1 where id=? and alert_count=0");
            pstmt.setLong(1, id);

            changedRows = pstmt.executeUpdate();
            txn.commit();
        } catch (Exception e) {
            s_logger.warn("Unexpected exception, ", e);
            throw new RuntimeException(e.getMessage(), e);
        }

        return changedRows;
    }

    protected ManagementServerHostDaoImpl() {
        MsIdSearch = createSearchBuilder();
        MsIdSearch.and("msid", MsIdSearch.entity().getMsid(), SearchCriteria.Op.EQ);
        MsIdSearch.done();

        ActiveSearch = createSearchBuilder();
        ActiveSearch.and("lastUpdateTime", ActiveSearch.entity().getLastUpdateTime(), SearchCriteria.Op.GT);
        ActiveSearch.and("removed", ActiveSearch.entity().getRemoved(), SearchCriteria.Op.NULL);
        ActiveSearch.done();

        InactiveSearch = createSearchBuilder();
        InactiveSearch.and("lastUpdateTime", InactiveSearch.entity().getLastUpdateTime(), SearchCriteria.Op.LTEQ);
        InactiveSearch.and("removed", InactiveSearch.entity().getRemoved(), SearchCriteria.Op.NULL);
        InactiveSearch.done();

        StateSearch = createSearchBuilder();
        StateSearch.and("state", StateSearch.entity().getState(), SearchCriteria.Op.IN);
        StateSearch.done();
    }

    @Override
    public void update(long id, long runId, State state, Date lastUpdate) {
        TransactionLegacy txn = TransactionLegacy.currentTxn();
        PreparedStatement pstmt = null;
        try {
            pstmt = txn.prepareAutoCloseStatement("update mshost set state=?, last_update=? where id=? and runid=?");
            pstmt.setString(1, state.toString());
            pstmt.setString(2, DateUtil.getDateDisplayString(TimeZone.getTimeZone("GMT"), lastUpdate));
            pstmt.setLong(3, id);
            pstmt.setLong(4, runId);

            int count = pstmt.executeUpdate();

            if (count < 1) {
                throw new CloudRuntimeException("Invalid cluster session detected", new ClusterInvalidSessionException("runid " + runId + " is no longer valid"));
            }
        } catch (SQLException e) {
            throw new CloudRuntimeException("DB exception on " + pstmt.toString(), e);
        }
    }

    @Override
    public List<ManagementServerHostVO> listBy(ManagementServerHost.State... states) {
        SearchCriteria<ManagementServerHostVO> sc = StateSearch.create();

        sc.setParameters("state", (Object[])states);

        return listBy(sc);
    }

    @Override
    public List<Long> listOrphanMsids() {
        List<Long> orphanList = new ArrayList<Long>();

        TransactionLegacy txn = TransactionLegacy.currentTxn();
        PreparedStatement pstmt = null;
        try {
            pstmt =
                txn.prepareAutoCloseStatement("select t.mgmt_server_id from (select mgmt_server_id, count(*) as count from host group by mgmt_server_id) as t WHERE t.count > 0 AND t.mgmt_server_id NOT IN (select msid from mshost)");

            ResultSet rs = pstmt.executeQuery();
            while (rs.next()) {
                orphanList.add(rs.getLong(1));
            }
        } catch (SQLException e) {
            throw new CloudRuntimeException("DB exception on " + pstmt.toString(), e);
        }

        return orphanList;
    }

    @Override
    public ManagementServerHostVO findOneInUpState(Filter filter) {
        SearchCriteria<ManagementServerHostVO> sc = StateSearch.create();

        sc.setParameters("state", ManagementServerHost.State.Up);

        List<ManagementServerHostVO> mshosts = listBy(sc, filter);
        if (mshosts != null && mshosts.size() > 0) {
            return mshosts.get(0);
        }
        return null;
    }

}
