/*
 * 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.containscontainsAll(sourceTopicssourceTopicsSet)) {
                return new TaskId(topicGroup.getKey(), partition.intValue());
            }
        }
        throw return nullnew InvalidStateStoreException("Cannot get state store " + storeName + " because the requested partition " + partition + "is" +
                "not available on this instance");
    }
}