/*
 * Copyright 2012-present the original author or authors.
 *
 * 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
 *
 *      https://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.springframework.boot.actuate.autoconfigure.tracing;

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

import org.springframework.boot.context.properties.ConfigurationProperties;

/**
 * Configuration properties for tracing.
 *
 * @author Moritz Halbritter
 * @author Jonatan Ivanov
 * @since 3.0.0
 */
@ConfigurationProperties("management.tracing")
public class TracingProperties {

	/**
	 * Sampling configuration.
	 */
	private final Sampling sampling = new Sampling();

	/**
	 * Baggage configuration.
	 */
	private final Baggage baggage = new Baggage();

	/**
	 * Propagation configuration.
	 */
	private final Propagation propagation = new Propagation();

	/**
	 * Brave configuration.
	 */
	private final Brave brave = new Brave();

	public Sampling getSampling() {
		return this.sampling;
	}

	public Baggage getBaggage() {
		return this.baggage;
	}

	public Propagation getPropagation() {
		return this.propagation;
	}

	public Brave getBrave() {
		return this.brave;
	}

	public static class Sampling {

		/**
		 * Probability in the range from 0.0 to 1.0 that a trace will be sampled.
		 */
		private float probability = 0.10f;

		public float getProbability() {
			return this.probability;
		}

		public void setProbability(float probability) {
			this.probability = probability;
		}

	}

	public static class Baggage {

		/**
		 * Whether to enable Micrometer Tracing baggage propagation.
		 */
		private boolean enabled = true;

		/**
		 * Correlation configuration.
		 */
		private Correlation correlation = new Correlation();

		/**
		 * List of fields that are referenced the same in-process as it is on the wire.
		 * For example, the field "x-vcap-request-id" would be set as-is including the
		 * prefix.
		 */
		private List<String> remoteFields = new ArrayList<>();

		/**
		 * List of fields that should be accessible within the JVM process but not
		 * propagated over the wire. Local fields are not supported with OpenTelemetry.
		 */
		private List<String> localFields = new ArrayList<>();

		/**
		 * List of fields that should automatically become tags.
		 */
		private List<String> tagFields = new ArrayList<>();

		public boolean isEnabled() {
			return this.enabled;
		}

		public void setEnabled(boolean enabled) {
			this.enabled = enabled;
		}

		public Correlation getCorrelation() {
			return this.correlation;
		}

		public void setCorrelation(Correlation correlation) {
			this.correlation = correlation;
		}

		public List<String> getRemoteFields() {
			return this.remoteFields;
		}

		public List<String> getLocalFields() {
			return this.localFields;
		}

		public List<String> getTagFields() {
			return this.tagFields;
		}

		public void setRemoteFields(List<String> remoteFields) {
			this.remoteFields = remoteFields;
		}

		public void setLocalFields(List<String> localFields) {
			this.localFields = localFields;
		}

		public void setTagFields(List<String> tagFields) {
			this.tagFields = tagFields;
		}

		public static class Correlation {

			/**
			 * Whether to enable correlation of the baggage context with logging contexts.
			 */
			private boolean enabled = true;

			/**
			 * List of fields that should be correlated with the logging context. That
			 * means that these fields would end up as key-value pairs in e.g. MDC.
			 */
			private List<String> fields = new ArrayList<>();

			public boolean isEnabled() {
				return this.enabled;
			}

			public void setEnabled(boolean enabled) {
				this.enabled = enabled;
			}

			public List<String> getFields() {
				return this.fields;
			}

			public void setFields(List<String> fields) {
				this.fields = fields;
			}

		}

	}

	public static class Propagation {

		/**
		 * Tracing context propagation types produced and consumed by the application.
		 * Setting this property overrides the more fine-grained propagation type
		 * properties.
		 */
		private List<PropagationType> type;

		/**
		 * Tracing context propagation types produced by the application.
		 */
		private List<PropagationType> produce = List.of(PropagationType.W3C);

		/**
		 * Tracing context propagation types consumed by the application.
		 */
		private List<PropagationType> consume = List.of(PropagationType.values());

		public void setType(List<PropagationType> type) {
			this.type = type;
		}

		public void setProduce(List<PropagationType> produce) {
			this.produce = produce;
		}

		public void setConsume(List<PropagationType> consume) {
			this.consume = consume;
		}

		public List<PropagationType> getType() {
			return this.type;
		}

		public List<PropagationType> getProduce() {
			return this.produce;
		}

		public List<PropagationType> getConsume() {
			return this.consume;
		}

		/**
		 * Returns the effective context propagation types produced by the application.
		 * This will be {@link #getType()} if set or {@link #getProduce()} otherwise.
		 * @return the effective context propagation types produced by the application
		 */
		List<PropagationType> getEffectiveProducedTypes() {
			return (this.type != null) ? this.type : this.produce;
		}

		/**
		 * Returns the effective context propagation types consumed by the application.
		 * This will be {@link #getType()} if set or {@link #getConsume()} otherwise.
		 * @return the effective context propagation types consumed by the application
		 */
		List<PropagationType> getEffectiveConsumedTypes() {
			return (this.type != null) ? this.type : this.consume;
		}

		/**
		 * Supported propagation types. The declared order of the values matter.
		 */
		public enum PropagationType {

			/**
			 * <a href="https://www.w3.org/TR/trace-context/">W3C</a> propagation.
			 */
			W3C,

			/**
			 * <a href="https://github.com/openzipkin/b3-propagation#single-header">B3
			 * single header</a> propagation.
			 */
			B3,

			/**
			 * <a href="https://github.com/openzipkin/b3-propagation#multiple-headers">B3
			 * multiple headers</a> propagation.
			 */
			B3_MULTI

		}

	}

	public static class Brave {

		/**
		 * Whether the propagation type and tracing backend support sharing the span ID
		 * between client and server spans. Requires B3 propagation and a compatible
		 * backend.
		 */
		private boolean spanJoiningSupported;

		public boolean isSpanJoiningSupported() {
			return this.spanJoiningSupported;
		}

		public void setSpanJoiningSupported(boolean spanJoiningSupported) {
			this.spanJoiningSupported = spanJoiningSupported;
		}

	}

}
