/*
 * Copyright (C) 2015 SoftIndex LLC.
 *
 * Licensed 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 io.datakernel.aggregation;

import com.google.common.base.MoreObjects;

import java.util.ArrayList;
import java.util.List;
import java.util.Objects;

import static io.datakernel.aggregation.AggregationPredicates.*;
import static java.util.Collections.unmodifiableList;

public class AggregationChunk {
	public static AggregationChunk create(int revisionId, long chunkId,
	                                      List<String> fields,
	                                      PrimaryKey minPrimaryKey, PrimaryKey maxPrimaryKey,
	                                      int count) {return new AggregationChunk(revisionId, chunkId, fields, minPrimaryKey, maxPrimaryKey, count);}

	public static class NewChunk {
		public final long chunkId;
		public final List<String> fields;
		public final PrimaryKey minPrimaryKey;
		public final PrimaryKey maxPrimaryKey;
		public final int count;

		public NewChunk(long chunkId, List<String> fields, PrimaryKey minPrimaryKey, PrimaryKey maxPrimaryKey, int count) {
			this.chunkId = chunkId;
			this.fields = fields;
			this.minPrimaryKey = minPrimaryKey;
			this.maxPrimaryKey = maxPrimaryKey;
			this.count = count;
		}

		@Override
		public String toString() {
			return MoreObjects.toStringHelper(this)
					.add("chunkId", chunkId)
					.add("fields", fields)
					.add("minPrimaryKey", minPrimaryKey)
					.add("maxPrimaryKey", maxPrimaryKey)
					.add("count", count)
					.toString();
		}
	}

	public static AggregationChunk createChunk(int revisionId, NewChunk newChunk) {
		return create(revisionId, newChunk.chunkId,
				newChunk.fields, newChunk.minPrimaryKey, newChunk.maxPrimaryKey, newChunk.count);
	}

	private final int revisionId;
	private final long chunkId;
	private final List<String> measures;
	private final PrimaryKey minPrimaryKey;
	private final PrimaryKey maxPrimaryKey;
	private final int count;

	private AggregationChunk(int revisionId, long chunkId,
	                         List<String> measures,
	                         PrimaryKey minPrimaryKey, PrimaryKey maxPrimaryKey,
	                         int count) {
		this.revisionId = revisionId;
		this.chunkId = chunkId;
		this.measures = measures;
		this.minPrimaryKey = minPrimaryKey;
		this.maxPrimaryKey = maxPrimaryKey;
		this.count = count;
	}

	public long getChunkId() {
		return chunkId;
	}

	public int getRevisionId() {
		return revisionId;
	}

	public List<String> getMeasures() {
		return unmodifiableList(measures);
	}

	public PrimaryKey getMinPrimaryKey() {
		return minPrimaryKey;
	}

	public PrimaryKey getMaxPrimaryKey() {
		return maxPrimaryKey;
	}

	public int getCount() {
		return count;
	}

	@Override
	public boolean equals(Object o) {
		if (this == o) return true;
		if (o == null || getClass() != o.getClass()) return false;
		AggregationChunk chunk = (AggregationChunk) o;
		return revisionId == chunk.revisionId &&
				chunkId == chunk.chunkId &&
				count == chunk.count &&
				Objects.equals(measures, chunk.measures) &&
				Objects.equals(minPrimaryKey, chunk.minPrimaryKey) &&
				Objects.equals(maxPrimaryKey, chunk.maxPrimaryKey);
	}

	@Override
	public int hashCode() {
		return Objects.hash(revisionId, chunkId, measures, minPrimaryKey, maxPrimaryKey, count);
	}

	public AggregationPredicate toPredicate(List<String> primaryKey) {
		List<AggregationPredicate> predicates = new ArrayList<>();
		for (int i = 0; i < primaryKey.size(); i++) {
			String key = primaryKey.get(i);
			Object from = minPrimaryKey.get(i);
			Object to = maxPrimaryKey.get(i);
			if (from.equals(to)) {
				predicates.add(eq(key, from));
			} else {
				predicates.add(between(key, (Comparable) from, (Comparable) to));
			}
		}
		return and(predicates);
	}

	@Override
	public String toString() {
		return "{" +
				"revision=" + revisionId +
				", id=" + chunkId +
				", measures=" + measures +
				", minKey=" + minPrimaryKey +
				", maxKey=" + maxPrimaryKey +
				", count=" + count +
				'}';
	}
}