package org.simantics.modeling;

import java.util.HashMap;
import java.util.Map;
import java.util.Set;

import org.simantics.Simantics;
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.WriteGraph;
import org.simantics.db.exception.DatabaseException;
import org.simantics.db.layer0.util.Layer0Utils;
import org.simantics.db.layer0.variable.AbstractPropertyVariable;
import org.simantics.db.layer0.variable.Variable;

class ImmutableComponentPropertyVariable extends AbstractPropertyVariable {

	final Variable parent;
	final ImmutableComponentPropertyContent content;

	@Override
	public int hashCode() {
		final int prime = 31;
		int result = 1;
		result = prime * result + ((content == null) ? 0 : content.hashCode());
		result = prime * result + ((parent == null) ? 0 : parent.hashCode());
		return result;
	}

	@Override
	public boolean equals(Object obj) {
		if (this == obj)
			return true;
		if (obj == null)
			return false;
		if (getClass() != obj.getClass())
			return false;
		ImmutableComponentPropertyVariable other = (ImmutableComponentPropertyVariable) obj;
		if (content == null) {
			if (other.content != null)
				return false;
		} else if (!content.equals(other.content))
			return false;
		if (parent == null) {
			if (other.parent != null)
				return false;
		} else if (!parent.equals(other.parent))
			return false;
		return true;
	}

	ImmutableComponentPropertyVariable(Variable parent, ImmutableComponentPropertyContent content) {
		this.parent = parent;
		this.content = content;
	}

	@Override
	public Resource getPropertyResource(ReadGraph graph) throws DatabaseException {
		return content.pi.predicate;
	}

	@Override
	public Resource getPossiblePredicateResource(ReadGraph graph) throws DatabaseException {
		return content.pi.predicate;
	}

	@Override
	public Resource getContainerResource(ReadGraph graph) throws DatabaseException {
		throw new IllegalStateException();
	}

	@Override
	public Datatype getDatatype(ReadGraph graph) throws DatabaseException {
		return Layer0Utils.getDatatype(graph, this);
	}

	@Override
	public Resource getPredicateResource(ReadGraph graph) throws DatabaseException {
		return content.pi.predicate;
	}

	@Override
	public Variable getPredicate(ReadGraph graph) throws DatabaseException {
		throw new IllegalStateException();
	}

	@Override
	public <T> T getValue(ReadGraph graph) throws DatabaseException {
		if(content.value != null) return (T)content.value;
		return (T)Simantics.applySCLRead(graph, content.expression, this);
	}

	@Override
	public <T> T getValue(ReadGraph graph, Binding binding) throws DatabaseException {
		if(content.value != null) return (T)content.value;
		return (T)Simantics.applySCLRead(graph, content.expression, this);
	}

	@Override
	public void setValue(WriteGraph graph, Object value, Binding binding) throws DatabaseException {
		throw new IllegalStateException();
	}

	@Override
	public String getName(ReadGraph graph) throws DatabaseException {
		return content.pi.name;
	}

	@Override
	public Variable getParent(ReadGraph graph) throws DatabaseException {
		return parent;
	}

	@Override
	public Set<String> getClassifications(ReadGraph graph) throws DatabaseException {
		return content.pi.classifications;
	}

	@Override
	protected Variable getPossibleDomainProperty(ReadGraph graph, String name) throws DatabaseException {

		if(content.properties == null)
			return null;

		ImmutableComponentPropertyContent p = content.properties.get(name);
		if(p != null)
			return new ImmutableComponentPropertyVariable(this, p);

		return null;

	}

	@Override
	public Map<String, Variable> collectDomainProperties(ReadGraph graph, Map<String, Variable> map)
			throws DatabaseException {

		if(content.properties == null)
			return map;

		if(map == null)
			map = new HashMap<>();

		for(ImmutableComponentPropertyContent p : content.properties.values()) {
			map.put(p.pi.name, new ImmutableComponentPropertyVariable(this, p));
		}

		return map;

	}

}