/*
 * 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.flink.runtime.metrics.dump;

/**
 * Container for scope related information as required by the MetricQueryService.
 */
public abstract class QueryScopeInfo {
	/** Categories to be returned by {@link QueryScopeInfo#getCategory()} to avoid instanceof checks. */
	public static final byte INFO_CATEGORY_JM = 0;
	public static final byte INFO_CATEGORY_TM = 1;
	public static final byte INFO_CATEGORY_JOB = 2;
	public static final byte INFO_CATEGORY_TASK = 3;
	public static final byte INFO_CATEGORY_OPERATOR = 4;

	/** The remaining scope not covered by specific fields */
	public final String scope;

	private QueryScopeInfo(String scope) {
		this.scope = scope;
	}

	/**
	 * Create a copy of this QueryScopeInfo and append the given scope.
	 *
	 * @param userScope scope to append
	 * @return modified copy of this QueryScopeInfo
	 */
	public abstract QueryScopeInfo copy(String userScope);

	/**
	 * Returns the category for this QueryScopeInfo.
	 * 
	 * @return category
     */
	public abstract byte getCategory();

	protected String concatScopes(String additionalScope) {
		return scope.isEmpty()
			? additionalScope
			: scope + "." + additionalScope;
	}

	/**
	 * Container for the job manager scope. Stores no additional information.
     */
	public static class JobManagerQueryScopeInfo extends QueryScopeInfo {
		public JobManagerQueryScopeInfo() {
			super("");
		}

		public JobManagerQueryScopeInfo(String scope) {
			super(scope);
		}

		@Override
		public JobManagerQueryScopeInfo copy(String additionalScope) {
			return new JobManagerQueryScopeInfo(concatScopes(additionalScope));
		}

		@Override
		public byte getCategory() {
			return INFO_CATEGORY_JM;
		}
	}

	/**
	 * Container for the task manager scope. Stores the ID of the task manager.
     */
	public static class TaskManagerQueryScopeInfo extends QueryScopeInfo {
		public final String taskManagerID;

		public TaskManagerQueryScopeInfo(String taskManagerId) {
			this(taskManagerId, "");
		}

		public TaskManagerQueryScopeInfo(String taskManagerId, String scope) {
			super(scope);
			this.taskManagerID = taskManagerId;
		}

		@Override
		public TaskManagerQueryScopeInfo copy(String additionalScope) {
			return new TaskManagerQueryScopeInfo(this.taskManagerID, concatScopes(additionalScope));
		}

		@Override
		public byte getCategory() {
			return INFO_CATEGORY_TM;
		}
	}

	/**
	 * Container for the job scope. Stores the ID of the job.
     */
	public static class JobQueryScopeInfo extends QueryScopeInfo {
		public final String jobID;

		public JobQueryScopeInfo(String jobID) {
			this(jobID, "");
		}

		public JobQueryScopeInfo(String jobID, String scope) {
			super(scope);
			this.jobID = jobID;
		}

		@Override
		public JobQueryScopeInfo copy(String additionalScope) {
			return new JobQueryScopeInfo(this.jobID, concatScopes(additionalScope));
		}

		@Override
		public byte getCategory() {
			return INFO_CATEGORY_JOB;
		}
	}

	/**
	 * Container for the task scope. Stores the ID of the job/vertex and subtask index.
     */
	public static class TaskQueryScopeInfo extends QueryScopeInfo {
		public final String jobID;
		public final String vertexID;
		public final int subtaskIndex;

		public TaskQueryScopeInfo(String jobID, String vertexid, int subtaskIndex) {
			this(jobID, vertexid, subtaskIndex, "");
		}

		public TaskQueryScopeInfo(String jobID, String vertexid, int subtaskIndex, String scope) {
			super(scope);
			this.jobID = jobID;
			this.vertexID = vertexid;
			this.subtaskIndex = subtaskIndex;
		}

		@Override
		public TaskQueryScopeInfo copy(String additionalScope) {
			return new TaskQueryScopeInfo(this.jobID, this.vertexID, this.subtaskIndex, concatScopes(additionalScope));
		}

		@Override
		public byte getCategory() {
			return INFO_CATEGORY_TASK;
		}
	}

	/**
	 * Container for the operator scope. Stores the ID of the job/vertex, the subtask index and the name of the operator.
     */
	public static class OperatorQueryScopeInfo extends QueryScopeInfo {
		public final String jobID;
		public final String vertexID;
		public final int subtaskIndex;
		public final String operatorName;

		public OperatorQueryScopeInfo(String jobID, String vertexid, int subtaskIndex, String operatorName) {
			this(jobID, vertexid, subtaskIndex, operatorName, "");
		}

		public OperatorQueryScopeInfo(String jobID, String vertexid, int subtaskIndex, String operatorName, String scope) {
			super(scope);
			this.jobID = jobID;
			this.vertexID = vertexid;
			this.subtaskIndex = subtaskIndex;
			this.operatorName = operatorName;
		}

		@Override
		public OperatorQueryScopeInfo copy(String additionalScope) {
			return new OperatorQueryScopeInfo(this.jobID, this.vertexID, this.subtaskIndex, this.operatorName, concatScopes(additionalScope));
		}

		@Override
		public byte getCategory() {
			return INFO_CATEGORY_OPERATOR;
		}
	}
}