/*
 * 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 org.apache.ignite.internal.processors.cache;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.HashSet;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.UUID;
import org.apache.ignite.internal.util.typedef.C1;
import org.apache.ignite.internal.util.typedef.F;
import org.apache.ignite.internal.util.typedef.internal.CU;
import org.jetbrains.annotations.Nullable;

/**
 * Cache change requests to execute when receive {@link DynamicCacheChangeBatch} event.
 */
public class ExchangeActions {
    /** */
    private List<CacheGroupActionData> cacheGrpsToStart;

    /** */
    private List<CacheGroupActionData> cacheGrpsToStop;

    /** */
    private Map<String, CacheActionData> cachesToStart;

    /**
     * Server nodes on which a successful start of the cache(s) is required, if any of these nodes fails when starting
     * the cache(s), the whole procedure is rolled back.
     */
    private Collection<UUID> cacheStartRequiredAliveNodes;

    /** */
    private Map<String, CacheActionData> cachesToStop;

    /** */
    private Map<String, CacheActionData> cachesToResetLostParts;

    /** */
    private LocalJoinCachesContext locJoinCtx;

    /** */
    private StateChangeRequest stateChangeReq;

    /**
     * @param grpId Group ID.
     * @return Always {@code true}, fails with assert error if inconsistent.
     */
    boolean checkStopRequestConsistency(int grpId) {
        Boolean destroy = null;

        // Check that caches associated with that group will be all stopped only or all destroyed.
        for (CacheActionData action : cacheStopRequests()) {
            if (action.descriptor().groupId() == grpId) {
                if (destroy == null)
                    destroy = action.request().destroy();
                else {
                    assert action.request().destroy() == destroy
                        : "Both cache stop only and cache destroy request associated with one group in batch "
                        + cacheStopRequests();
                }
            }
        }

        return true;
    }

    /**
     * @return {@code True} if server nodes should not participate in exchange.
     */
    public boolean clientOnlyExchange() {
        return F.isEmpty(cachesToStart) &&
            F.isEmpty(cachesToStop) &&
            F.isEmpty(cacheGrpsToStart) &&
            F.isEmpty(cacheGrpsToStop) &&
            F.isEmpty(cachesToResetLostParts);
    }

    /**
     * @return New caches start requests.
     */
    public Collection<CacheActionData> cacheStartRequests() {
        return cachesToStart != null ? cachesToStart.values() : Collections.emptyList();
    }

    /**
     * @return Stop cache requests.
     */
    public Collection<CacheActionData> cacheStopRequests() {
        return cachesToStop != null ? cachesToStop.values() : Collections.emptyList();
    }

    /**
     * @param ctx Context.
     * @param err Error if any.
     */
    public void completeRequestFutures(GridCacheSharedContext ctx, Throwable err) {
        completeRequestFutures(cachesToStart, ctx, err);
        completeRequestFutures(cachesToStop, ctx, err);
        completeRequestFutures(cachesToResetLostParts, ctx, err);
    }

    /**
     * @return {@code True} if starting system caches.
     */
    public boolean systemCachesStarting() {
        if (cachesToStart != null) {
            for (CacheActionData data : cachesToStart.values()) {
                if (CU.isSystemCache(data.request().cacheName()))
                    return true;
            }
        }

        return false;
    }

    /**
     * @param map Actions map.
     * @param ctx Context.
     */
    private void completeRequestFutures(
        Map<String, CacheActionData> map,
        GridCacheSharedContext ctx,
        @Nullable Throwable err
    ) {
        if (map != null) {
            for (CacheActionData req : map.values())
                ctx.cache().completeCacheStartFuture(req.req, (err == null), err);
        }
    }

    /**
     * @return {@code True} if have cache stop requests.
     */
    public boolean hasStop() {
        return !F.isEmpty(cachesToStop);
    }

    /**
     * @return Caches to reset lost partitions for.
     */
    public Set<String> cachesToResetLostPartitions() {
        Set<String> caches = null;

        if (cachesToResetLostParts != null)
            caches = new HashSet<>(cachesToResetLostParts.keySet());

        return caches != null ? caches : Collections.<String>emptySet();
    }

    /**
     * @param cacheId Cache ID.
     * @return {@code True} if cache stop was requested.
     */
    public boolean cacheStopped(int cacheId) {
        if (cachesToStop != null) {
            for (CacheActionData cache : cachesToStop.values()) {
                if (cache.desc.cacheId() == cacheId)
                    return true;
            }
        }

        return false;
    }

    /**
     * @param cacheId Cache ID.
     * @return {@code True} if cache start was requested.
     */
    public boolean cacheStarted(int cacheId) {
        if (cachesToStart != null) {
            for (CacheActionData cache : cachesToStart.values()) {
                if (cache.desc.cacheId() == cacheId)
                    return true;
            }
        }

        return false;
    }

    /**
     * @param stateChange Cluster state change request.
     */
    public void stateChangeRequest(StateChangeRequest stateChange) {
        this.stateChangeReq = stateChange;
    }

    /**
     * @return {@code True} if has deactivate request.
     */
    public boolean deactivate() {
        return stateChangeReq != null && stateChangeReq.activeChanged() && !stateChangeReq.state().active();
    }

    /**
     * @return {@code True} if has activate request.
     */
    public boolean activate() {
        return stateChangeReq != null && stateChangeReq.activeChanged() && stateChangeReq.state().active();
    }

    /**
     * @return {@code True} if cluster state was changed.
     */
    public boolean changedClusterState() {
        return stateChangeReq != null && stateChangeReq.prevState() != stateChangeReq.state();
    }

    /**
     * @return {@code True} if has baseline topology change request.
     */
    public boolean changedBaseline() {
        return stateChangeReq != null && !stateChangeReq.activeChanged();
    }

    /**
     * @return Cluster state change request.
     */
    @Nullable public StateChangeRequest stateChangeRequest() {
        return stateChangeReq;
    }

    /**
     * @param map Actions map.
     * @param req Request.
     * @param desc Cache descriptor.
     * @return Actions map.
     */
    private Map<String, CacheActionData> add(Map<String, CacheActionData> map,
        DynamicCacheChangeRequest req,
        DynamicCacheDescriptor desc) {
        assert req != null;
        assert desc != null;

        if (map == null)
            map = new LinkedHashMap<>();

        CacheActionData old = map.put(req.cacheName(), new CacheActionData(req, desc));

        assert old == null : old;

        return map;
    }

    /**
     * @param req Request.
     * @param desc Cache descriptor.
     */
    void addCacheToStart(DynamicCacheChangeRequest req, DynamicCacheDescriptor desc) {
        assert req.start() : req;

        cachesToStart = add(cachesToStart, req, desc);
    }

    /**
     * @param req Request.
     * @param desc Cache descriptor.
     */
    public void addCacheToStop(DynamicCacheChangeRequest req, DynamicCacheDescriptor desc) {
        assert req.stop() : req;

        cachesToStop = add(cachesToStop, req, desc);
    }

    /**
     * @param req Request.
     * @param desc Cache descriptor.
     */
    void addCacheToResetLostPartitions(DynamicCacheChangeRequest req, DynamicCacheDescriptor desc) {
        assert req.resetLostPartitions() : req;

        cachesToResetLostParts = add(cachesToResetLostParts, req, desc);
    }

    /**
     * @param grpDesc Group descriptor.
     */
    void addCacheGroupToStart(CacheGroupDescriptor grpDesc) {
        assert grpDesc != null;

        if (cacheGrpsToStart == null)
            cacheGrpsToStart = new ArrayList<>();

        cacheGrpsToStart.add(new CacheGroupActionData(grpDesc));
    }

    /**
     * @return Cache groups to start.
     */
    public List<CacheGroupActionData> cacheGroupsToStart() {
        return cacheGrpsToStart != null ? cacheGrpsToStart : Collections.<CacheGroupActionData>emptyList();
    }

    /**
     * @param grpId Group ID.
     * @return {@code True} if given cache group starting.
     */
    public boolean cacheGroupStarting(int grpId) {
        if (cacheGrpsToStart != null) {
            for (CacheGroupActionData grp : cacheGrpsToStart) {
                if (grp.desc.groupId() == grpId)
                    return true;
            }
        }

        return false;
    }

    /**
     * @return Server nodes on which a successful start of the cache(s) is required, if any of these nodes fails when
     *      starting the cache(s), the whole procedure is rolled back.
     */
    public Collection<UUID> cacheStartRequiredAliveNodes() {
        return cacheStartRequiredAliveNodes == null ? Collections.emptyList() : cacheStartRequiredAliveNodes;
    }

    /**
     * @param cacheStartRequiredAliveNodes Server nodes on which a successful start of the cache(s) is required, if any
     *                                     of these nodes fails when starting the cache(s), the whole procedure is
     *                                     rolled back.
     */
    public void cacheStartRequiredAliveNodes(Collection<UUID> cacheStartRequiredAliveNodes) {
        this.cacheStartRequiredAliveNodes = new ArrayList<>(cacheStartRequiredAliveNodes);
    }

    /**
     * @param grpDesc Group descriptor.
     * @param destroy Destroy flag.
     */
    public void addCacheGroupToStop(CacheGroupDescriptor grpDesc, boolean destroy) {
        assert grpDesc != null;

        if (cacheGrpsToStop == null)
            cacheGrpsToStop = new ArrayList<>();

        cacheGrpsToStop.add(new CacheGroupActionData(grpDesc, destroy));
    }

    /**
     * @return Cache groups to start.
     */
    public List<CacheGroupActionData> cacheGroupsToStop() {
        return cacheGrpsToStop != null ? cacheGrpsToStop : Collections.<CacheGroupActionData>emptyList();
    }

    /**
     * @param grpId Group ID.
     * @return {@code True} if given cache group stopping.
     */
    public boolean cacheGroupStopping(int grpId) {
        if (cacheGrpsToStop != null) {
            for (CacheGroupActionData grp : cacheGrpsToStop) {
                if (grp.desc.groupId() == grpId)
                    return true;
            }
        }

        return false;
    }

    /**
     * @return {@code True} if there are no cache change actions.
     */
    public boolean empty() {
        return F.isEmpty(cachesToStart) &&
            F.isEmpty(cachesToStop) &&
            F.isEmpty(cacheGrpsToStart) &&
            F.isEmpty(cacheGrpsToStop) &&
            F.isEmpty(cachesToResetLostParts) &&
            stateChangeReq == null &&
            locJoinCtx == null;
    }

    /**
     * @param locJoinCtx Caches local join context.
     */
    public void localJoinContext(LocalJoinCachesContext locJoinCtx) {
        this.locJoinCtx = locJoinCtx;
    }

    /**
     * @return Caches local join context.
     */
    public LocalJoinCachesContext localJoinContext() {
        return locJoinCtx;
    }

    /**
     *
     */
    public static class CacheActionData {
        /** */
        private final DynamicCacheChangeRequest req;

        /** */
        private final DynamicCacheDescriptor desc;

        /**
         * @param req Request.
         * @param desc Cache descriptor.
         */
        CacheActionData(DynamicCacheChangeRequest req, DynamicCacheDescriptor desc) {
            assert req != null;
            assert desc != null;

            this.req = req;
            this.desc = desc;
        }

        /**
         * @return Request.
         */
        public DynamicCacheChangeRequest request() {
            return req;
        }

        /**
         * @return Cache descriptor.
         */
        public DynamicCacheDescriptor descriptor() {
            return desc;
        }
    }

    /**
     *
     */
    public static class CacheGroupActionData {
        /** */
        private final CacheGroupDescriptor desc;

        /** */
        private final boolean destroy;

        /**
         * @param desc Group descriptor
         * @param destroy Destroy flag
         */
        CacheGroupActionData(CacheGroupDescriptor desc, boolean destroy) {
            assert desc != null;

            this.desc = desc;
            this.destroy = destroy;
        }

        /**
         * @param desc Group descriptor
         */
        CacheGroupActionData(CacheGroupDescriptor desc) {
            this(desc, false);
        }

        /**
         * @return Group descriptor
         */
        public CacheGroupDescriptor descriptor() {
            return desc;
        }

        /**
         * @return Destroy flag
         */
        public boolean destroy() {
            return destroy;
        }
    }

    /** {@inheritDoc} */
    @Override public String toString() {
        Object startGrps = F.viewReadOnly(cacheGrpsToStart, new C1<CacheGroupActionData, String>() {
            @Override public String apply(CacheGroupActionData data) {
                return data.desc.cacheOrGroupName();
            }
        });
        Object stopGrps = F.viewReadOnly(cacheGrpsToStop, new C1<CacheGroupActionData, String>() {
            @Override public String apply(CacheGroupActionData data) {
                return data.desc.cacheOrGroupName() + ", destroy=" + data.destroy;
            }
        });

        return "ExchangeActions [startCaches=" + (cachesToStart != null ? cachesToStart.keySet() : null) +
            ", stopCaches=" + (cachesToStop != null ? cachesToStop.keySet() : null) +
            ", startGrps=" + startGrps +
            ", stopGrps=" + stopGrps +
            ", resetParts=" + (cachesToResetLostParts != null ? cachesToResetLostParts.keySet() : null) +
            ", stateChangeRequest=" + stateChangeReq + ']';
    }
}
