package org.gcube.informationsystem.utils.documentation.model;

import java.util.Collection;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;

import org.gcube.informationsystem.base.reference.AccessType;
import org.gcube.informationsystem.discovery.knowledge.UsageKnowledge;
import org.gcube.informationsystem.types.reference.Type;
import org.gcube.informationsystem.types.reference.properties.LinkedEntity;
import org.gcube.informationsystem.types.reference.properties.PropertyDefinition;
import org.gcube.informationsystem.utils.documentation.rst.Section;
import org.gcube.informationsystem.utils.documentation.rst.Section.SectionType;
import org.gcube.informationsystem.utils.documentation.rst.table.Cell;
import org.gcube.informationsystem.utils.documentation.rst.table.Row;
import org.gcube.informationsystem.utils.documentation.rst.table.RowType;
import org.gcube.informationsystem.utils.documentation.rst.table.Table;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * @author Luca Frosini (ISTI - CNR)
 */
public abstract class DocumentationGenerator {
	
	private static final Logger logger = LoggerFactory.getLogger(DocumentationGenerator.class);
	
	private static final int DEFAULT_NUMBER_OF_COLUMNS = 5;
	
	public static final String NO_ADDITIONAL_ATTRIBUTE = "This type does not define any additional attributes.";
	public static final String NO_SPECIFIC_KNOWN_USAGE = "No specific known usage for this type.";
	
	protected static int defaultOffsetLevel = 0;
	
	public static int getDefaultOffsetLevel() {
		return defaultOffsetLevel;
	}

	public static void setDefaultOffsetLevel(int defaultOffsetLevel) {
		DocumentationGenerator.defaultOffsetLevel = defaultOffsetLevel;
	}

	protected final Type type;
	protected final AccessType requiredType;
	protected String superClassToBeExcluded;
	protected int requiredNumberOfColumns;
	protected int offsetLevel;
	protected int level;
	
	protected UsageKnowledge facetKnowledge;
	protected UsageKnowledge resourceKnowledge;
	
	public UsageKnowledge getFacetKnowledge() {
		return facetKnowledge;
	}

	public void setFacetKnowledge(UsageKnowledge facetKnowledge) {
		this.facetKnowledge = facetKnowledge;
	}

	public UsageKnowledge getResourceKnowledge() {
		return resourceKnowledge;
	}

	public void setResourceKnowledge(UsageKnowledge resourceKnowledge) {
		this.resourceKnowledge = resourceKnowledge;
	}
	
	protected DocumentationGenerator(Type type, AccessType requiredType) {
		this.type = type;
		this.requiredType = requiredType;
		AccessType accessType = type.getAccessType();
		if(accessType!=requiredType) {
			throw new RuntimeException(type.getName() + " is not a " + requiredType.getName() + " type");
		}
		this.requiredNumberOfColumns = DEFAULT_NUMBER_OF_COLUMNS;
		this.superClassToBeExcluded = null;
		this.offsetLevel = DocumentationGenerator.defaultOffsetLevel;
	}
	
	public void setLevel(int level) {
		this.level = level;
	}
	
	public void setOffsetLevel(int offsetLevel) {
		this.offsetLevel = offsetLevel;
	}
	protected Row getPropertyFieldsBoldRow() {
		Row row = new Row(RowType.NORMAL);
		Cell name = new Cell();
		name.setText("**Name**");
		row.appendCell(name);
		Cell type = new Cell();
		type.setText("**Type**");
		row.appendCell(type);
		Cell attributes = new Cell();
		attributes.setText("**Attributes**");
		row.appendCell(attributes);
		Cell description = new Cell();
		description.setText("**Description**");
		row.appendCell(description);
		for(int i=row.getCells().size(); i<requiredNumberOfColumns; i++) {
			row.appendCell(description);
		}
		return row;
	}

	
	protected Row getPropertyFieldsHeadingRow() {
		Row row = new Row(RowType.HEADING);
		Cell name = new Cell();
		name.setText("Name");
		row.appendCell(name);
		Cell type = new Cell();
		type.setText("Type");
		row.appendCell(type);
		Cell attributes = new Cell();
		attributes.setText("Attributes");
		row.appendCell(attributes);
		Cell description = new Cell();
		description.setText("Description");
		row.appendCell(description);
		for(int i=row.getCells().size(); i<requiredNumberOfColumns; i++) {
			row.appendCell(description);
		}
		return row;
	}
	
	protected Row getSourceTargetBoldRow() {
		Row row = new Row(RowType.NORMAL);
		Cell source = new Cell();
		source.setText("**Source**");
		row.appendCell(source);
		Cell relation = new Cell();
		relation.setText("**Relation**");
		row.appendCell(relation);
		Cell multiplicity = new Cell();
		multiplicity.setText("**Multiplicity**");
		row.appendCell(multiplicity);
		Cell target = new Cell();
		target.setText("**Target**");
		row.appendCell(target);
		Cell description = new Cell();
		description.setText("**Description**");
		row.appendCell(description);
		for(int i=row.getCells().size(); i<requiredNumberOfColumns; i++) {
			row.appendCell(description);
		}
		return row;
	}
	
	protected Row getSourceTargetHeadingRow() {
		Row row = new Row(RowType.HEADING);
		Cell source = new Cell();
		source.setText("Source");
		row.appendCell(source);
		Cell relation = new Cell();
		relation.setText("Relation");
		row.appendCell(relation);
		Cell multiplicity = new Cell();
		multiplicity.setText("Multiplicity");
		row.appendCell(multiplicity);
		Cell target = new Cell();
		target.setText("Target");
		row.appendCell(target);
		Cell description = new Cell();
		description.setText("Description");
		row.appendCell(description);
		for(int i=row.getCells().size(); i<requiredNumberOfColumns; i++) {
			row.appendCell(description);
		}
		return row;
	}
	
	protected Row getKnownUsageBoldRow() {
		Row row = new Row(RowType.NORMAL);
		row = addCellSpanToRow(row, "**Known Usage**", requiredNumberOfColumns);
		return row;
	}
	
	protected Row getPropertiesBoldRow() {
		Row row = new Row(RowType.NORMAL);
		row = addCellSpanToRow(row, "**Properties**", requiredNumberOfColumns);
		return row;
	}
	
	protected Row getLinkedEntityrow(LinkedEntity linkedEntity) {
		Row row = new Row(RowType.NORMAL);
		Cell source = new Cell();
		source.setText(linkedEntity.getSource());
		row.appendCell(source);
		
		Cell relation = new Cell();
		relation.setText(linkedEntity.getRelation());
		row.appendCell(relation);
		
		Cell multiplicity = new Cell();
		StringBuffer buffer = new StringBuffer();
		Integer min = linkedEntity.getMin();
		buffer.append(min==null? "0" : min.toString());
		buffer.append("..");
		Integer max = linkedEntity.getMax();
		buffer.append(max==null? "n" : max.toString());
		multiplicity.setText(buffer.toString());
		row.appendCell(multiplicity);
		
		Cell target = new Cell();
		target.setText(linkedEntity.getTarget());
		row.appendCell(target);
		
		Cell description = new Cell();
		description.setText(linkedEntity.getDescription());
		row.appendCell(description);
		
		for(int i=row.getCells().size(); i<requiredNumberOfColumns; i++) {
			row.appendCell(description);
		}
		
		return row;
	}
	
	protected Table addLinkedEntities(Table table, Collection<LinkedEntity> entities, String messageFroNullOrEmptyCollection) {
		if(entities!=null && entities.size()>0) {
			for(LinkedEntity entity : entities) {
				Row row = getLinkedEntityrow(entity);
				table.appendRow(row);
			}
		}else {
			Row row = getRowCellSpan(messageFroNullOrEmptyCollection, requiredNumberOfColumns);;
			table.appendRow(row);
		}
		return table;
	}
	
	protected String getPropertyAttributes(PropertyDefinition propertyDefinition) {
		StringBuffer stringBuffer = new StringBuffer();
		
		boolean mandatory = propertyDefinition.isMandatory();
		stringBuffer.append("``Mandatory:");
		stringBuffer.append(mandatory);
		
		boolean readOnly = propertyDefinition.isReadonly();
		stringBuffer.append("`` ``ReadOnly:");
		stringBuffer.append(readOnly);
		
		boolean notNull = propertyDefinition.isNotnull();
		stringBuffer.append("`` ``NotNull:");
		stringBuffer.append(notNull);
		
		String regex = propertyDefinition.getRegexp();
		if(regex!=null && regex.compareTo("")!=0) {
			stringBuffer.append("`` ``Regex:");
			stringBuffer.append(regex);
		}
		
		Integer max = propertyDefinition.getMax();
		if(max!=null) {
			stringBuffer.append("`` ``Max:");
			stringBuffer.append(max);
		}
		
		Integer min = propertyDefinition.getMin();
		if(min!=null) {
			stringBuffer.append("`` ``Min:");
			stringBuffer.append(min);
		}
		stringBuffer.append("``");
		return stringBuffer.toString();
	}
	
	protected Row getPropertyRow(PropertyDefinition propertyDefinition) {
		Row row = new Row(RowType.NORMAL);
		Cell name = new Cell();
		name.setText(propertyDefinition.getName());
		row.appendCell(name);
		Cell type = new Cell();
		type.setText(propertyDefinition.getType());
		row.appendCell(type);
		Cell attributes = new Cell();
		attributes.setText(getPropertyAttributes(propertyDefinition));
		row.appendCell(attributes);
		Cell description = new Cell();
		description.setText(propertyDefinition.getDescription());
		row.appendCell(description);
		for(int i=row.getCells().size(); i<requiredNumberOfColumns; i++) {
			row.appendCell(description);
		}
		return row;
	}
	
	protected Row getNoPropertyRow() {
		return getRowCellSpan(NO_ADDITIONAL_ATTRIBUTE, requiredNumberOfColumns);
	}
	
	protected Row addCellSpanToRow(Row row, String content, int cellSpan) {
		Cell cellToSpan = new Cell();
		cellToSpan.setText(content);
		for(int i=0; i<cellSpan; i++) {
			row.appendCell(cellToSpan);
		}
		return row;
	}
	
	protected Row getRowCellSpan(String content, int cellSpan) {
		Row row = new Row(RowType.NORMAL);
		return addCellSpanToRow(row, content, cellSpan);
	}
	
	protected Row getHeadingRowCellSpan(String content, int cellSpan) {
		Row row = new Row(RowType.HEADING);
		return addCellSpanToRow(row, content, cellSpan);
	}
	
	protected Table addPropertyRows(Table table, Set<PropertyDefinition> properties) {
		table.appendRow(getPropertyFieldsBoldRow());
		if(properties!=null && properties.size()>0) {
			Set<PropertyDefinition> notMandatoryProperties = new HashSet<>();
			for(PropertyDefinition propertyDefinition : properties) {
				if(propertyDefinition.isMandatory()) {
					/*
					 * Adding Mandatory properties first in the table
					 */
					table.appendRow(getPropertyRow(propertyDefinition));
				}else {
					notMandatoryProperties.add(propertyDefinition);
				}
			}
			for(PropertyDefinition propertyDefinition : notMandatoryProperties) {
				table.appendRow(getPropertyRow(propertyDefinition));
			}
		}else {
			table.appendRow(getNoPropertyRow());
		}
		return table;
	}
	
	/*
	 * E.g. GCubeProperty extends Property
	 */
	protected StringBuffer getTypeDeclaration() {
		StringBuffer stringBuffer = new StringBuffer();
		stringBuffer.append("**");
		stringBuffer.append(type.getName());
		stringBuffer.append("**");
		Set<String> superClasses = type.getSuperClasses();
		if(superClassToBeExcluded!=null) {
			superClasses.remove(superClassToBeExcluded);
		}
		if(superClasses.size()>0){
			stringBuffer.append(" ``extends`` ");
			boolean first = true;
			for(String superClass : superClasses) {
				if(!first) {
					stringBuffer.append(", ");
				}else {
					first = false;
				}
				stringBuffer.append("**");
				stringBuffer.append(superClass);
				stringBuffer.append("**");
			}
		}
		return stringBuffer;
	}
	
	public Section getSection() {
		Section section = new Section();
		int sectionLevel = level+offsetLevel;
		SectionType[] sectionTypes =  SectionType.values();
		int maxSectionLevel = sectionTypes.length-1;
		sectionLevel = sectionLevel>=maxSectionLevel ? maxSectionLevel : sectionLevel;  
		SectionType sectionType = SectionType.values()[sectionLevel];
		section.setSectionType(sectionType);
		return section;
	}
	
	public StringBuffer generateSection() {
		StringBuffer stringBuffer = new StringBuffer();
		stringBuffer.append("\n");
		Section section = getSection();
		String name = type.getName();
		stringBuffer.append(section.generate(name));
		return stringBuffer;
	}
	
	protected StringBuffer generateChangelog() {
		StringBuffer stringBuffer = new StringBuffer();
		stringBuffer.append("The **");
		stringBuffer.append(type.getName());
		stringBuffer.append("** current version is ");
		stringBuffer.append(type.getVersionAsString());
		stringBuffer.append(".\n\n");
		Map<String, String> changelog = type.getChangelogWithVersionAsString();
		Set<String> keySet = changelog.keySet();
		stringBuffer.append("Changelog:\n\n");
		int i=0;
		for(String version : keySet) {
			stringBuffer.append("* **");
			stringBuffer.append(version);
			stringBuffer.append("**: ");
			stringBuffer.append(changelog.get(version));
			if(i==keySet.size()-1) {
				stringBuffer.append(".");
			}else {
				stringBuffer.append(";");
			}
		}
		stringBuffer.append("\n\n");
		return stringBuffer;
	}

	protected abstract Table getTable();
	
	protected StringBuffer generateTable() {
		StringBuffer stringBuffer = new StringBuffer();
		String tableTitle = getTypeDeclaration().toString();
		Table table = getTable();
		stringBuffer.append(table.generateTable(tableTitle));
		return stringBuffer;
	}
	
	public StringBuffer generate() {
		StringBuffer stringBuffer = generateSection();
		stringBuffer.append(type.getDescription());
		stringBuffer.append("\n");
		stringBuffer.append(generateTable());
		stringBuffer.append(generateChangelog());
		logger.trace(stringBuffer.toString());
		return stringBuffer;
	}
}