/*
* 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.kafka.streams;


/**
* Represents all the query options that a user can provide to state what kind of stores it is expecting.
* The options would be whether a user would want to enable/disable stale stores
* or whether it knows the list of partitions that it specifically wants to fetch.
* If this information is not provided the default behavior is to fetch the stores for all the
* partitions available on that instance for that particular store name.
* It contains a list of partitions, which for a point queries can be populated from the  KeyQueryMetadata.
*/
public class StoreQueryParams {


private final List<Integer> partitions;


private final boolean includeStaleStores;


public StoreQueryParams(final List<Integer> partitions, final boolean includeStaleStores) {
this.partitions = partitions;
this.includeStaleStores = includeStaleStores;
}


/**
* Get the list of partitions to be used to fetch list of Queryable store from QueryableStoreProvider. 
*
* @return list of partitions
*/
public List<Integer> getPartitions() {
return partitions;
}

/**
* Get the flag includeStaleStores. If true, include standbys and recovering stores along with running stores
*
* @return includeStaleStores
*/
public boolean getIncludeStaleStores() {
return includeStaleStores;
}


@Override
public boolean equals(final Object obj) {
if (!(obj instanceof StoreQueryParams)) {
return false;
}
final StoreQueryParams storeQueryParams = (StoreQueryParams) obj;
return Objects.equals(storeQueryParams.partitions, partitions)
&& Objects.equals(storeQueryParams.includeStaleStores, includeStaleStores);
}


@Override
public String toString() {
return "StoreQueryParams {" +
"partitions=" + partitions +
", includeStaleStores=" + includeStaleStores +
'}';
}


@Override
public int hashCode() {
return Objects.hash(partitions, includeStaleStores);
}
}

 public <T> T store(final String storeName, final QueryableStoreType<T> queryableStoreType) {
 return store(storeName, queryableStoreType, new StoreQueryParams(null, false));
 }   


public <T> T store(final String storeName, final QueryableStoreType<T> queryableStoreType, final StoreQueryParams storeQueryParams) {
validateIsRunningOrRebalancing();
return queryableStoreProvider.getStore(storeName, queryableStoreType, storeQueryParams);
}

 public <T> T getStore(final String storeName, final QueryableStoreType<T> queryableStoreType, final StoreQueryParams storeQueryParams) {
        final List<T> globalStore = globalStoreProvider.stores(storeName, queryableStoreType);
        if (!globalStore.isEmpty()) {
            return queryableStoreType.create(globalStoreProvider, storeName);
        }
        final List<T> allStores = new ArrayList<>();
        for (final StreamThreadStateStoreProvider storeProvider : storeProviders) {
            allStores.addAll(storeProvider.stores(storeName, queryableStoreType, storeQueryParams));
        }
        if (allStores.isEmpty()) {
            throw new InvalidStateStoreException("The state store, " + storeName + ", may have migrated to another instance.");
        }
        return queryableStoreType.create(
            new WrappingStoreProvider(storeProviders, storeQueryParams),
            storeName
        );
 }

/*
 * 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.kafka.streams.state.internals;

import org.apache.kafka.streams.StoreQueryParams;
import org.apache.kafka.streams.errors.InvalidStateStoreException;
import org.apache.kafka.streams.processor.StateStore;
import org.apache.kafka.streams.processor.TaskId;
import org.apache.kafka.streams.processor.internals.InternalTopologyBuilder;
import org.apache.kafka.streams.processor.internals.StreamThread;
import org.apache.kafka.streams.processor.internals.Task;
import org.apache.kafka.streams.state.QueryableStoreType;
import org.apache.kafka.streams.state.QueryableStoreTypes;
import org.apache.kafka.streams.state.TimestampedKeyValueStore;
import org.apache.kafka.streams.state.TimestampedWindowStore;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.stream.Collectors;

public class StreamThreadStateStoreProvider {

    private final StreamThread streamThread;
    private final InternalTopologyBuilder internalTopologyBuilder;

    public StreamThreadStateStoreProvider(final StreamThread streamThread, final InternalTopologyBuilder internalTopologyBuilder) {
        this.streamThread = streamThread;
        this.internalTopologyBuilder = internalTopologyBuilder;
    }

    @SuppressWarnings("unchecked")
    public <T> List<T> stores(final String storeName,
                              final QueryableStoreType<T> queryableStoreType,
                              final StoreQueryParams storeQueryParams) {

        final TaskId keyTaskId = createKeyTaskId(storeName, storeQueryParams.getPartition());
        if (streamThread.state() == StreamThread.State.DEAD) {
            return Collections.emptyList();
        }
        final StreamThread.State state = streamThread.state();
        if (storeQueryParams.getIncludeStaleStores() ? state.isAlive() : state == StreamThread.State.RUNNING) {
            final Map<TaskId, ? extends Task> tasks = storeQueryParams.getIncludeStaleStores() ? streamThread.allTasks() : streamThread.activeTasks();
            final List<T> stores = new ArrayList<>();
            for (final Task streamTask : tasks.values()) {
                if (keyTaskId != null && !keyTaskId.equals(streamTask.id())) {
                    continue;
                }
                final StateStore store = streamTask.getStore(storeName);
                if (store != null && queryableStoreType.accepts(store)) {
                    if (!store.isOpen()) {
                        throw new InvalidStateStoreException(
                                "Cannot get state store " + storeName + " for task " + streamTask +
                                        " because the store is not open. " +
                                        "The state store may have migrated to another instances.");
                    }
                    if (store instanceof TimestampedKeyValueStore && queryableStoreType instanceof QueryableStoreTypes.KeyValueStoreType) {
                        stores.add((T) new ReadOnlyKeyValueStoreFacade<>((TimestampedKeyValueStore<Object, Object>) store));
                    } else if (store instanceof TimestampedWindowStore && queryableStoreType instanceof QueryableStoreTypes.WindowStoreType) {
                        stores.add((T) new ReadOnlyWindowStoreFacade<>((TimestampedWindowStore<Object, Object>) store));
                    } else {
                        stores.add((T) store);
                    }
                }
            }
            return stores;
        } else {
            throw new InvalidStateStoreException("Cannot get state store " + storeName + " because the stream thread is " +
                    state + ", not RUNNING" +
                    (storeQueryParams.getIncludeStaleStores() ? " or REBALANCING" : ""));
        }
    }

    private TaskId createKeyTaskId(final String storeName, final Integer partition) {
        if (partition == null) {
            return null;
        }
        final List<String> sourceTopics = internalTopologyBuilder.stateStoreNameToSourceTopics().get(storeName);
        final Set<String> sourceTopicsSet = sourceTopics.stream().collect(Collectors.toSet());
        final Map<Integer, InternalTopologyBuilder.TopicsInfo> topicGroups = internalTopologyBuilder.topicGroups();
        for (final Map.Entry<Integer, InternalTopologyBuilder.TopicsInfo> topicGroup : topicGroups.entrySet()) {
            if (topicGroup.getValue().sourceTopics.containsAll(sourceTopicsSet)) {
                return new TaskId(topicGroup.getKey(), partition.intValue());
            }
        }
        throw new InvalidStateStoreException("Cannot get state store " + storeName + " because the requested partition " + partition + "is" +
                "not available on this instance");
    }
}