/*-
    * #%L
    * io.earcam.instrumental.module.osgi
    * %%
    * Copyright (C) 2018 earcam
    * %%
    * SPDX-License-Identifier: (BSD-3-Clause OR EPL-1.0 OR Apache-2.0 OR MIT)
    * 
    * You <b>must</b> choose to accept, in full - any individual or combination of 
   * the following licenses:
   * <ul>
   * 	<li><a href="https://opensource.org/licenses/BSD-3-Clause">BSD-3-Clause</a></li>
   * 	<li><a href="https://www.eclipse.org/legal/epl-v10.html">EPL-1.0</a></li>
   * 	<li><a href="https://www.apache.org/licenses/LICENSE-2.0">Apache-2.0</a></li>
   * 	<li><a href="https://opensource.org/licenses/MIT">MIT</a></li>
   * </ul>
   * #L%
   */
  package io.earcam.instrumental.module.osgi;
  
  import static io.earcam.instrumental.module.osgi.OsgiAttributeConstants.VERSION_ATTRIBUTE;
  import static java.util.Collections.emptyMap;
  
  import java.io.IOException;
  import java.util.HashMap;
  import java.util.Iterator;
  import java.util.Map;
  import java.util.Map.Entry;
  import java.util.Objects;
  
  import io.earcam.instrumental.fluent.Fluent;
  import io.earcam.unexceptional.Exceptional;
  
  /**
   * <p>
   * ClauseParameters class.
   * </p>
   *
   * @see ClauseParameter for construction
   */
  public final class ClauseParameters {
  
  	public static final class ClauseParameter {
  
  		private ClauseParameter()
  		{}
  
  
  		@Fluent
  		public static ClauseParameters directive(String key, String value)
  		{
  			ClauseParameters parameters = new ClauseParameters();
  			parameters.directive(key, value);
  			return parameters;
  		}
  
  
  		@Fluent
  		public static ClauseParameters attribute(String key, String value)
  		{
  			ClauseParameters parameters = new ClauseParameters();
  			parameters.attribute(key, value);
  			return parameters;
  		}
  
  
  		@Fluent
  		public static ClauseParameters version(int major, int minor, int micro)
  		{
  			ClauseParameters parameters = new ClauseParameters();
  			parameters.attribute(VERSION_ATTRIBUTE.value, major + "." + minor + "." + micro);
  			return parameters;
  		}
  	}
  
  	/**
  	 * Empty parameters, immutably so
  	 */
  	public static final ClauseParameters EMPTY_PARAMETERS = new ClauseParameters(emptyMap(), emptyMap());
  
  	private final Map<String, String> attributes;
  	private final Map<String, String> directives;
  
  
  	/**
  	 * <p>
  	 * Constructor for ClauseParameters.
  	 * </p>
  	 */
  	public ClauseParameters()
  	{
  		this(new HashMap<>(), new HashMap<>());
  	}
  
  
  	/**
  	 * <p>
  	 * Constructor for ClauseParameters.
  	 * </p>
 	 *
 	 * @param attributes a {@link java.util.Map} object.
 	 * @param directives a {@link java.util.Map} object.
 	 * @see ClauseParameter#attribute(String, String)
 	 * @see ClauseParameter#directive(String, String)
 	 * @see ClauseParameter#attribute(String, String)
 	 * @see ClauseParameter#directive(String, String)
 	 */
 	public ClauseParameters(Map<String, String> attributes, Map<String, String> directives)
 	{
 		this.attributes = attributes;
 		this.directives = directives;
 	}
 
 
 	@Override
 	public String toString()
 	{
 		return Exceptional.apply(this::appendTo, new StringBuilder()).toString();
 	}
 
 
 	@Override
 	public boolean equals(Object other)
 	{
 		return other instanceof ClauseParameters && equals((ClauseParameters) other);
 	}
 
 
 	/**
 	 * <p>
 	 * equals.
 	 * </p>
 	 *
 	 * @param that a {@link io.earcam.instrumental.module.osgi.ClauseParameters} object.
 	 * @return a boolean.
 	 */
 	public boolean equals(ClauseParameters that)
 	{
 		return that != null
 				&& that.attributes.equals(this.attributes)
 				&& that.directives.equals(this.directives);
 	}
 
 
 	@Override
 	public int hashCode()
 	{
 		return Objects.hash(attributes, directives);
 	}
 
 
 	/**
 	 * <p>
 	 * isEmpty.
 	 * </p>
 	 *
 	 * @return a boolean.
 	 */
 	public boolean isEmpty()
 	{
 		return attributes().isEmpty()
 				&& directives().isEmpty();
 	}
 
 
 	/**
 	 * <p>
 	 * directives.
 	 * </p>
 	 *
 	 * @return a {@link java.util.Map} object.
 	 */
 	public Map<String, String> directives()
 	{
 		return directives;
 	}
 
 
 	/**
 	 * <p>
 	 * directive.
 	 * </p>
 	 *
 	 * @param key a {@link java.lang.String} object.
 	 * @param value a {@link java.lang.String} object.
 	 * @return a {@link io.earcam.instrumental.module.osgi.ClauseParameters} object.
 	 */
 	public ClauseParameters directive(String key, String value)
 	{
 		directives.put(key, value);
 		return this;
 	}
 
 
 	/**
 	 * <p>
 	 * attributes.
 	 * </p>
 	 *
 	 * @return a modifiable {@link Map}.
 	 */
 	public Map<String, String> attributes()
 	{
 		return attributes;
 	}
 
 
 	/**
 	 * <p>
 	 * attribute.
 	 * </p>
 	 *
 	 * @param key a {@link java.lang.String} object.
 	 * @param value a {@link java.lang.String} object.
 	 * @return a {@link io.earcam.instrumental.module.osgi.ClauseParameters} object.
 	 */
 	public ClauseParameters attribute(String key, String value)
 	{
 		attributes.put(key, value);
 		return this;
 	}
 
 
 	/**
 	 * <p>
 	 * appendTo.
 	 * </p>
 	 *
 	 * @param appendix a {@link java.lang.Appendable} object.
 	 * @return a {@link java.lang.Appendable} object.
 	 * @throws java.io.IOException if any.
 	 */
 	public Appendable appendTo(Appendable appendix) throws IOException
 	{
 		appendTo(appendix, attributes, "=");
 		appendTo(appendix, directives, ":=");
 		return appendix;
 	}
 
 
 	private void appendTo(Appendable appendage, Map<String, String> source, String symbol) throws IOException
 	{
 		if(!source.isEmpty()) {
 			appendage.append(';');
 			for(Iterator<Entry<String, String>> it = source.entrySet().iterator(); it.hasNext();) {
 				Entry<String, String> entry = it.next();
 				appendage.append(entry.getKey()).append(symbol);
 
 				if(entry.getValue().indexOf('.') != -1 ||
 						entry.getValue().indexOf(',') != -1) {
 					appendage.append('"').append(entry.getValue()).append('"');
 				} else {
 					appendage.append(entry.getValue());
 				}
 				if(it.hasNext()) {
 					appendage.append(';');
 				}
 			}
 		}
 	}
 
 
 	/**
 	 * <p>
 	 * attributeOrDefault.
 	 * </p>
 	 *
 	 * @param name a {@link java.lang.String} object.
 	 * @param defaultValue a {@link java.lang.String} object.
 	 * @return a {@link java.lang.String} object.
 	 */
 	public String attributeOrDefault(String name, String defaultValue)
 	{
 		String value = attribute(name);
 		return (value == null) ? defaultValue : value;
 	}
 
 
 	/**
 	 * <p>
 	 * attribute.
 	 * </p>
 	 *
 	 * @param name a {@link java.lang.String} object.
 	 * @return a {@link java.lang.String} object.
 	 */
 	public String attribute(String name)
 	{
 		return attributes().get(name);
 	}
 }