/*-
 * ============LICENSE_START=======================================================
 * org.openecomp.aai
 * ================================================================================
 * Copyright (C) 2017 AT&T Intellectual Property. All rights reserved.
 * ================================================================================
 * 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.
 * ============LICENSE_END=========================================================
 */

package org.openecomp.aai.introspection.tools;

import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import java.util.Optional;
import java.util.Set;

import org.openecomp.aai.db.props.AAIProperties;
import org.openecomp.aai.exceptions.AAIException;
import org.openecomp.aai.introspection.Introspector;
import org.openecomp.aai.introspection.IntrospectorWalker;
import org.openecomp.aai.introspection.Visibility;
import org.openecomp.aai.introspection.Wanderer;
import org.openecomp.aai.schema.enums.PropertyMetadata;

public class IntrospectorValidator implements Wanderer {

	
	private List<Issue> issues = null;
	private List<IssueResolver> issueResolvers = null; 
	private boolean validateRequired = true;
	private final int maximumDepth;
	private int currentDepth = 0;
	
	private final Set<String> relationshipChain;
	/**
	 * Instantiates a new introspector validator.
	 *
	 * @param builder the builder
	 */
	private IntrospectorValidator(IntrospectorValidator.Builder builder) {
		this.validateRequired = builder.getValidateRequired();
		this.issueResolvers = builder.getResolvers();
		this.maximumDepth = builder.getMaximumDepth();
		issues = new ArrayList<>();
		
		relationshipChain = new HashSet<>();
		
		relationshipChain.add("relationship-list");
		relationshipChain.add("relationship");
		relationshipChain.add("relationship-data");
		relationshipChain.add("related-to-property");


	}
	
	/**
	 * Validate.
	 *
	 * @param obj the obj
	 * @return true, if successful
	 * @throws AAIException 
	 */
	public boolean validate(Introspector obj) throws AAIException {
		IntrospectorWalker walker = new IntrospectorWalker(this);
		this.currentDepth = 0;
		walker.walk(obj);
		
		for (Issue m : issues) {
			if (!m.getSeverity().equals(Severity.WARNING)) {
				return false;
			}
		}
		
		return true;
	}
	
	/**
	 * Gets the issues.
	 *
	 * @return the issues
	 */
	public List<Issue> getIssues() {
		return this.issues;
	}
	
	/**
	 * Sets the issue resolvers.
	 *
	 * @param resolvers the new issue resolvers
	 */
	public void setIssueResolvers(List<IssueResolver> resolvers) {
		issueResolvers = new ArrayList<>();
		for (IssueResolver resolver : resolvers) {
			issueResolvers.add(resolver);
		}
	}
	
	/**
	 * Resolve issues.
	 *
	 * @return true, if successful
	 */
	public boolean resolveIssues() {
		boolean result = true;
		for (Issue issue : issues) {
			for (IssueResolver resolver : issueResolvers) {
				if (resolver.resolveIssue(issue)) {
					issue.setResolved(true);
				}
			}
			if (!issue.isResolved()) {
				result = false;
			}
		}
		
		return result;
	}
	
	/**
	 * {@inheritDoc}
	 */
	@Override
	public void processComplexObj(Introspector obj) {
				
		if (this.currentDepth > this.maximumDepth && !relationshipChain.contains(obj.getDbName())) {
			Issue message = 
					this.buildMessage(Severity.CRITICAL, IssueType.EXCEEDED_ALLOWED_DEPTH, "Maximum allowed depth of this object has been exceeded on: " + obj.getDbName());
			message.setIntrospector(obj);
			issues.add(message);
		}
		Set<String> requiredProps = obj.getRequiredProperties();
		Set<String> keys = obj.getKeys();
		Set<String> props = obj.getProperties();
		
		for (String prop : props) {
			Object value = obj.getValue(prop);
			if (keys.contains(prop)) {
				if (value == null) {
					Issue message = 
							this.buildMessage(Severity.CRITICAL, IssueType.MISSING_KEY_PROP, "Missing key property: " + prop);
					message.setIntrospector(obj);
					message.setPropName(prop);
					issues.add(message);
				}
			} else if (requiredProps.contains(prop)) {
				if (value == null && validateRequired) {
					Issue message = 
							this.buildMessage(Severity.CRITICAL, IssueType.MISSING_REQUIRED_PROP, "Missing required property: " + prop);
					message.setIntrospector(obj);
					message.setPropName(prop);
					issues.add(message);
				}
			}
			
			final Optional<String> visibility = obj.getPropertyMetadata(prop, PropertyMetadata.VISIBILITY);
			if(visibility.isPresent() && Visibility.internal.equals(Visibility.valueOf(visibility.get()))) {
				Issue message =
						this.buildMessage(Severity.ERROR, IssueType.PROPERTY_NOT_VISIBLE, "client attemptted to set property not visible: " + prop);
				message.setIntrospector(obj);
				message.setPropName(prop);
				issues.add(message);
				
			}			
		}
		
		if (!relationshipChain.contains(obj.getDbName())) {
			this.currentDepth++;
		}

	}

	/**
	 * {@inheritDoc}
	 */
	@Override
	public void processPrimitive(String propName, Introspector obj) {
		//NO OP
	}

	/**
	 * {@inheritDoc}
	 */
	@Override
	public void processPrimitiveList(String propName, Introspector obj) {
		//NO OP
	}

	/**
	 * {@inheritDoc}
	 */
	@Override
	public void modifyComplexList(List<Introspector> list, List<Object> listReference, Introspector parent, Introspector child) {
		//NO OP
	}
	
	
	/**
	 * Builds the message.
	 *
	 * @param severity the severity
	 * @param error the error
	 * @param detail the detail
	 * @return the issue
	 */
	private Issue buildMessage(Severity severity, IssueType error, String detail) {
		Issue message = new Issue();
		message.setSeverity(severity);
		message.setType(error);
		message.setDetail(detail);
		
		return message;
	}

	/**
	 * {@inheritDoc}
	 */
	@Override
	public boolean createComplexObjIfNull() {
		return false;
	}

	/**
	 * {@inheritDoc}
	 */
	@Override
	public int createComplexListSize(Introspector parent, Introspector child) {
		return 0;
	}
	
	public static class Builder {
		
		private boolean validateRequired = true;
		private List<IssueResolver> issueResolvers = null;
		private int maximumDepth = AAIProperties.MAXIMUM_DEPTH;
		/**
		 * Instantiates a new builder.
		 *
		 * @param llBuilder the ll builder
		 */
		public Builder() {
			issueResolvers = new ArrayList<IssueResolver>();
		}
		
		/**
		 * Validate required.
		 *
		 * @param validateRequired the validate required
		 * @return the builder
		 */
		public Builder validateRequired(boolean validateRequired) {
			this.validateRequired = validateRequired;
			return this;
		}
		
		public Builder restrictDepth(int depth) {
			this.maximumDepth = depth; 
			return this;
		}
		/**
		 * Adds the resolver.
		 *
		 * @param resolver the resolver
		 * @return the builder
		 */
		public Builder addResolver(IssueResolver resolver) {
			issueResolvers.add(resolver);
			return this;
		}
		
		/**
		 * Builds the.
		 *
		 * @return the introspector validator
		 */
		public IntrospectorValidator build() {
			return new IntrospectorValidator(this);
		}
		
		/**
		 * Gets the validate required.
		 *
		 * @return the validate required
		 */
		public boolean getValidateRequired() {
			return this.validateRequired;
		}
		
		/**
		 * Gets the resolvers.
		 *
		 * @return the resolvers
		 */
		public List<IssueResolver> getResolvers() {
			return this.issueResolvers;
		}
		
		public int getMaximumDepth() {
			return this.maximumDepth;
		}
	}
	
}