EDIT

package eu.etaxonomy.cdm.api.service;

import java.util.ArrayList;

import java.util.HashSet;

import java.util.Iterator;

import java.util.List;

import java.util.Map;

import java.util.Set;

import org.apache.commons.lang.StringUtils;

import org.apache.log4j.Logger;

import org.springframework.stereotype.Component;

import eu.etaxonomy.cdm.model.description.CategoricalData;

import eu.etaxonomy.cdm.model.description.DescriptionElementBase;

import eu.etaxonomy.cdm.model.description.Feature;

import eu.etaxonomy.cdm.model.description.FeatureNode;

import eu.etaxonomy.cdm.model.description.FeatureTree;

import eu.etaxonomy.cdm.model.description.QuantitativeData;

import eu.etaxonomy.cdm.model.description.TaxonDescription;

import eu.etaxonomy.cdm.model.description.TextData;

import eu.etaxonomy.cdm.model.description.TextFormat;

import eu.etaxonomy.cdm.model.common.Annotation;

import eu.etaxonomy.cdm.model.common.AnnotationType;

import eu.etaxonomy.cdm.model.common.Language;

/**

 * Generator of natural language descriptions from TaxonDescriptions.

 * 

 * @author m.venin

 * @created 13.04.2010

 * @version 1.0

 */

@Component

public class NaturalLanguageGenerator implements INaturalLanguageGenerator {

	@SuppressWarnings("unused")

	private static final Logger logger = Logger.getLogger(NaturalLanguageGenerator.class);

	private String firstSeparator = ",";

	private String secondSeparator = ".";

	private List<Integer> levels = new ArrayList<Integer>();

	private DescriptionBuilder<QuantitativeData> quantitativeDescriptionBuilder = new DefaultQuantitativeDescriptionBuilder();

	private DescriptionBuilder<CategoricalData> categoricalDescriptionBuilder = new DefaultCategoricalDescriptionBuilder();

	private TextData previousTextData;

	DeltaTextDataProcessor deltaTextDataProcessor = new DeltaTextDataProcessor();

	private Map<String, INaturalLanguageTextDataProcessor> elementProcessors;

	private Set<INaturalLanguageTextDataProcessor> applicableElementProcessors = new HashSet<INaturalLanguageTextDataProcessor>();

	/**

	 * Change the first separator used by generateSingleTextData. By default ",".

	 * 

	 * @param separator

	 */

	public void setFirstSeparator(String separator){

		firstSeparator=separator;

	}

	public String getFirstSeparator(){

		return firstSeparator;

	}

	/**

	 * Change the second separator used by generateSingleTextData. By default ".".

	 * 

	 * @param separator

	 */

	public void setSecondSeparator(String separator){

		secondSeparator=separator;

	}

	public String getSecondSeparator(){

		return secondSeparator;

	}

	/**

	 * @param quantitativeDescriptionBuilder

	 */

	public void setQuantitativeDescriptionBuilder(DescriptionBuilder<QuantitativeData> quantitativeDescriptionBuilder){

		this.quantitativeDescriptionBuilder = quantitativeDescriptionBuilder;

	}

	/**

	 * @param categoricalDescriptionBuilder

	 */

	public void setCategoricalDescriptionBuilder(DescriptionBuilder<CategoricalData> categoricalDescriptionBuilder){

		this.categoricalDescriptionBuilder = categoricalDescriptionBuilder;

	}

	/**

	 * @return the element processors of this generator

	 */

	public Map<String, INaturalLanguageTextDataProcessor> getElementProcessors() {

		return elementProcessors;

	}

	/**

	 * The keys of the elementProcessors map are regular expressions which are

	 * being used to identify the those Descriptions to which the mapped

	 * NaturalLanguageTextDataProcessor is applicable.

	 * 

	 * @param elementProcessors

	 */

	public void setElementProcessors(

			Map<String, INaturalLanguageTextDataProcessor> elementProcessors) {

		this.elementProcessors = elementProcessors;

	}

	/**

	 * Looks for technical annotations, if one matches a regular expression of the element processors

	 * the associated processor is added to the applicable element processors which will then be applied

	 * when generating the description.

	 * 

	 * @param annotations the set of annotations of the description

	 */

	private void initNaturalLanguageDescriptionElementProcessors(Set<Annotation> annotations) {

		if(annotations != null){

			for(Annotation annotation : annotations){

				if(annotation.getAnnotationType().equals(AnnotationType.TECHNICAL())){

					if (elementProcessors!=null){

						for(String regex : elementProcessors.keySet()){

							if(annotation.getText().matches(regex)){

								applicableElementProcessors.add(elementProcessors.get(regex));

							}

						}

					}

				}

			}

		}

	}

	/**

	 * Applies the list of applicable processors to a TextData.

	 * 

	 * @param textData the TextData to be modified

	 * @param previousTextData the TextData corresponding to the feature of the previous level in the tree

	 */

	private void applyNaturalLanguageDescriptionElementProcessors(TextData textData, TextData previousTextData){

		for(INaturalLanguageTextDataProcessor processor : applicableElementProcessors){

			processor.process(textData, previousTextData);

		}

	}

	/**

	 * The most simple function to generate a description. The language used is the default one.

	 * 

	 * @param featureTree the FeatureTree holding the order in which features and their states must be printed

	 * @param description the TaxonDescription with all the data

	 * 

	 * @return a list of TextData, each one being a basic element of the natural language description

	 */

	public List<TextData> generateNaturalLanguageDescription(FeatureTree featureTree,TaxonDescription description) {

		return generateNaturalLanguageDescription(featureTree,description,Language.DEFAULT());

	}

	/**

	 * Generate a description in a specified language.

	 * 

	 * @param featureTree the FeatureTree holding the order in which features and their states must be printed

	 * @param description the TaxonDescription with all the data

	 * @param language the language in which the description has to be printed

	 * 

	 * @return a list of TextData, each one being a basic element of the natural language description

	 */

	public List<TextData> generateNaturalLanguageDescription(FeatureTree featureTree, TaxonDescription description,	Language language) {

		List<Language> languages = new ArrayList<Language>();

		languages.add(language);

		initNaturalLanguageDescriptionElementProcessors(description.getAnnotations());

		return generatePreferredNaturalLanguageDescription(featureTree,description,languages);

	}

	/**

	 * Generate a description with a specified list of preferred languages.

	 * 

	 * @param featureTree the FeatureTree holding the order in which features and their states must be printed

	 * @param description the TaxonDescription with all the data

	 * @param languages the ordered list of languages preferred for printing the description

	 * 

	 * @return a list of TextData, each one being a basic element of the natural language description

	 */

	public List<TextData> generatePreferredNaturalLanguageDescription(FeatureTree featureTree,TaxonDescription description, List<Language> languages) {

		initNaturalLanguageDescriptionElementProcessors(description.getAnnotations());

		return buildBranchesDescr(featureTree.getRootChildren(), featureTree.getRoot(), description, languages,0);

	}

	/**

	 * Generate a description as a single paragraph in a TextData.

	 * 

	 * @param featureTree the FeatureTree holding the order in which features and their states must be printed

	 * @param description the TaxonDescription with all the data

	 * 

	 * @return a TextData in the default language.

	 */

	public TextData generateSingleTextData(FeatureTree featureTree, TaxonDescription description) {

		return generateSingleTextData(featureTree,description,Language.DEFAULT());

	}

	/**

	 * Generate a description as a single paragraph in a TextData.

	 * 

	 * @param featureTree the FeatureTree holding the order in which features and their states must be printed

	 * @param description the TaxonDescription with all the data

	 * @param language the language in which the description has to be printed

	 * 

	 * @return a TextData in the specified language.

	 */

	public TextData generateSingleTextData(FeatureTree featureTree, TaxonDescription description, Language language) {

		List<Language> languages = new ArrayList<Language>();

		languages.add(language);

		return generatePreferredSingleTextData(featureTree,description,languages);

	}

	/**

	 * Generate a description with a specified list of preferred languages.

	 * 

	 * @param featureTree the FeatureTree holding the order in which features and their states must be printed

	 * @param description the TaxonDescription with all the data

	 * @param languages the ordered list of languages preferred for printing the description

	 * 

	 * @return a TextData using the languages (in the given order of preference)

	 */

	public TextData generatePreferredSingleTextData(FeatureTree featureTree, TaxonDescription description, List<Language> languages) {

		levels.clear(); // before the start, the table containing the levels of each node must be cleared

		// Note: this is not the most efficient way to keep track of the levels of the nodes but it allows some flexibility

		List<TextData> texts = generatePreferredNaturalLanguageDescription(featureTree,description, languages);// first get the description as a raw list of TextData

		StringBuilder descriptionStringBuilder = new StringBuilder(); // the StringBuilder used to generate the description

		int i = 0,j,level; // i is used to store the index of the TextData to use

		boolean startSentence = false, firstOne = true;

		for (j=0 ; j<levels.size() ; j++){

			level = levels.get(j);

			if (level==-1){

				if ((j+1)<levels.size() && levels.get(j+1).equals(0)){ // if this node is the direct father of a leaf

					descriptionStringBuilder.append(secondSeparator + " ");

					startSentence=true;

					firstOne=false;

					String asString = texts.get(i).getText(Language.DEFAULT()).toString();

					if (asString.length()>1) descriptionStringBuilder.append(asString.substring(0,1).toUpperCase() + asString.substring(1));

				}

				i++;

			}

			else if (level==0) { // if this node is a leaf

				if (startSentence) descriptionStringBuilder.append(texts.get(i).getText(Language.DEFAULT()));

				else descriptionStringBuilder.append(firstSeparator + texts.get(i).getText(Language.DEFAULT()));

				startSentence=false;

				i++;

			}

			else {

				if (!firstOne && levels.get(j-1).equals(0)){ // if this node corresponds to the states linked to the previous leaf

					if (i<texts.size()) descriptionStringBuilder.append(texts.get(i).getText(Language.DEFAULT()));

					i++;

				}

			}

		}

		descriptionStringBuilder.append(secondSeparator);

		String returnString = descriptionStringBuilder.toString();

		returnString = StringUtils.replace(returnString, "  ", " ");

		returnString = StringUtils.removeStart(returnString, secondSeparator + " ");

		return TextData.NewInstance(returnString,Language.DEFAULT(),TextFormat.NewInstance("", "Text", ""));

	}

	/** recursive function that goes through a tree containing the order in which the description has to be generated,

	 *  if an element of this tree matches one of the TaxonDescription, a DescriptionBuilder is called which returns a TextData with the corresponding description.

	 * 

	 * @param children the children of the feature node considered

	 * @param parent the feature node considered

	 * @param description the TaxonDescription element for which we want a natural language output

	 * @param language The language in which the description has to be written

	 * @param floor integer to keep track of the level in the tree

	 * @return a list of TextData elements containing the part of description corresponding to the feature node considered

	 */

	private List<TextData> buildBranchesDescr(List<FeatureNode> children, FeatureNode parent, TaxonDescription description, List<Language> languages, int floor) {

		List<TextData> listTextData = new ArrayList<TextData>();

		floor++; // counter to know the current level in the tree

		if (!parent.isLeaf()){ // if this node is not a leaf, continue recursively (only the leaves of a FeatureTree contain states)

			levels.add(new Integer(floor)); // the level of the different nodes in the tree are kept, thus it is easier to build a structured text out of the List<TextData>

			Feature feature = parent.getFeature();

			TextData featureName;

			if (feature!=null && feature.getLabel()!=null){ // if a node is associated to a feature

				featureName = categoricalDescriptionBuilder.buildTextDataFeature(feature, languages);

				levels.add(new Integer(-1)); // it is indicated by a '-1' after its level

				listTextData.add(featureName); // the TextData representing the name of the feature is concatenated to the list

			}

			else featureName = new TextData(); // else an empty TextData is created (because we keep track of the features, it is useful to inform when the upper node has no feature attached)

			for (Iterator<FeatureNode> ifn = children.iterator() ; ifn.hasNext() ;){

				previousTextData = featureName; // this allows to keep track of the name of the feature one level up in the tree

				FeatureNode fn = ifn.next();

				listTextData.addAll(buildBranchesDescr(fn.getChildNodes(),fn,description, languages, floor));

			}

		}

		else { //once a leaf is reached

			Feature feature = parent.getFeature();

			if (feature!=null && (feature.isSupportsQuantitativeData() || feature.isSupportsCategoricalData())) {

				Set<DescriptionElementBase> elements = description.getElements();

				for (Iterator<DescriptionElementBase> deb = elements.iterator() ; deb.hasNext() ;){ // iterates over all the descriptions enclosed in the TaxonDescription

					DescriptionElementBase descriptionElement = deb.next();

					if (descriptionElement.getFeature().equals(feature)){ // if one matches the corresponding feature associated to this leaf

						if (descriptionElement instanceof CategoricalData || descriptionElement instanceof QuantitativeData){

							TextData featureTextData;

							TextData statesTextData;

							if (descriptionElement instanceof CategoricalData) { // if this description is a CategoricalData, generate the according TextData

								CategoricalData categoricalData = (CategoricalData) descriptionElement;

								statesTextData = categoricalDescriptionBuilder.build(categoricalData, languages);

								featureTextData = categoricalDescriptionBuilder.buildTextDataFeature(feature, languages);

							}

							else { // if this description is a QuantitativeData, generate the according TextData

								QuantitativeData quantitativeData = (QuantitativeData) descriptionElement;

								statesTextData = quantitativeDescriptionBuilder.build(quantitativeData, languages);

								featureTextData = quantitativeDescriptionBuilder.buildTextDataFeature(feature, languages);

							}

							applyNaturalLanguageDescriptionElementProcessors(featureTextData, previousTextData);

							levels.add(new Integer(0)); // 0 indicates a feature, which is a leaf of the tree

							listTextData.add(featureTextData);

							levels.add(new Integer(floor)); // this represents the level of the feature and means it is followed by a TextData containing the states of the feature

							listTextData.add(statesTextData);

						}

					}

				}

			}

		}

		return listTextData;

	}	

}