package org.simantics.db.layer0.request;

import gnu.trove.map.hash.THashMap;

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

import org.simantics.databoard.Bindings;
import org.simantics.databoard.accessor.reference.ChildReference;
import org.simantics.databoard.accessor.reference.IndexReference;
import org.simantics.databoard.accessor.reference.NameReference;
import org.simantics.databoard.binding.Binding;
import org.simantics.databoard.type.Datatype;
import org.simantics.db.ReadGraph;
import org.simantics.db.Resource;
import org.simantics.db.common.request.ResourceRead;
import org.simantics.db.exception.DatabaseException;
import org.simantics.db.layer0.util.Layer0Utils;
import org.simantics.db.layer0.variable.ValueAccessor;
import org.simantics.db.layer0.variable.VariableBuilder;
import org.simantics.layer0.Layer0;
import org.simantics.operation.Layer0X;
import org.simantics.utils.datastructures.Pair;

final public class PropertyInfoRequest extends ResourceRead<PropertyInfo> {

	public PropertyInfoRequest(Resource resource) {
		super(resource);
	}

	@Override
	public PropertyInfo perform(ReadGraph graph) throws DatabaseException {
		
		Layer0 L0 = Layer0.getInstance(graph);
		Layer0X L0X = Layer0X.getInstance(graph);
		
		boolean isHasProperty = graph.isSubrelationOf(resource, L0.HasProperty);
		
		String name = graph.getPossibleRelatedValue(resource, L0.HasName, Bindings.STRING);
		if(name != null) name = name.intern();
		
		boolean isFunctional = graph.isInstanceOf(resource, L0.FunctionalRelation);
		
		Set<String> classifications = graph.sync(new ClassificationsRequest(graph.getPrincipalTypes(resource)));
		VariableBuilder<?> variableBuilder = graph.getPossibleAdapter(resource, VariableBuilder.class);
		
		Datatype requiredDataType = graph.getPossibleRelatedValue(resource, L0X.RequiresDataType, Bindings.DATATYPE);
		
		String definedUnit = graph.getPossibleRelatedValue(resource, L0X.HasUnit, Bindings.STRING);
		
		Resource literalRange = graph.getPossibleObject(resource, L0.HasRange);
		String requiredValueType = graph.getPossibleRelatedValue(resource, L0.RequiresValueType, Bindings.STRING);
		//System.out.println(name + " -> " + requiredValueType);
		
		ValueAccessor accessor = graph.getPossibleRelatedValue2(resource, Layer0.getInstance(graph).valueAccessor, resource);
		
		boolean hasEnumerationRange = graph.syncRequest(new HasEnumerationRange(resource));

		Collection<Resource> ranges = graph.getObjects(resource, L0.HasRange);
		if (!ranges.isEmpty()) {
			for (Resource range : ranges) {
				if (requiredValueType == null) {
					// Check if the single range defines value type
					Collection<Resource> valueTypes = graph.getAssertedObjects(range, L0.HasValueType);
					if (valueTypes.size() > 0) {
						for (Resource valueType : valueTypes) {
							String vt = graph.getPossibleValue(valueType, Bindings.STRING);
							if (vt != null && !vt.isEmpty()) {
								requiredValueType = vt;
								continue;
							}
						}
					}
				}

				Collection<Resource> subliterals = graph.getObjects(range, L0.HasSubliteralPredicate);
				if(!subliterals.isEmpty()) {
					Map<String,Pair<Resource, ChildReference>> map = new THashMap<String,Pair<Resource, ChildReference>>(); 
					for(Resource p : subliterals) {
						String pN = graph.getPossibleRelatedValue(p, L0.HasName, Bindings.STRING);
						if(pN == null) continue;
						if(pN.startsWith("n-")) {
							ChildReference r = new NameReference(pN.substring(2));
							map.put(pN, Pair.make(p, r));
						} else if (pN.startsWith("i-")) {
							ChildReference r = new IndexReference(Integer.parseInt(pN.substring(2)));
							map.put(pN, Pair.make(p, r));
						}
					}
					
					return PropertyInfo.make(graph, resource, name, isFunctional, isHasProperty, classifications, variableBuilder, literalRange, requiredDataType, definedUnit, requiredValueType, map, accessor, hasEnumerationRange);
					
				}
			}
		}
		
		return PropertyInfo.make(graph, resource, name, isFunctional, isHasProperty, classifications, variableBuilder, literalRange, requiredDataType, definedUnit, requiredValueType, Collections.<String,Pair<Resource,ChildReference>>emptyMap(), accessor, hasEnumerationRange);
		
	}
	
	@Override
	public boolean equals(Object object) {
        if (this == object)
            return true;
        else if (object == null)
            return false;
        else if (!(object instanceof PropertyInfoRequest))
            return false;
        PropertyInfoRequest r = (PropertyInfoRequest)object;
        return r.resource.equals(resource);
	}
	
	@Override
	public int hashCode() {
		return resource.hashCode() + classHash;
	}
	
	private static int classHash = 31*PropertyInfo.class.hashCode();

}