package org.simantics.modeling;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;

import org.simantics.db.ReadGraph;
import org.simantics.db.Resource;
import org.simantics.db.exception.DatabaseException;
import org.simantics.db.layer0.variable.AbstractChildVariable;
import org.simantics.db.layer0.variable.StandardGraphChildVariable;
import org.simantics.db.layer0.variable.Variable;

public class ImmutableComponentVariable extends AbstractChildVariable {

	@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;
		ImmutableComponentVariable other = (ImmutableComponentVariable) 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;
	}

	final private Variable parent;
	final private ImmutableComponentVariableContent content;
	
	ImmutableComponentVariable(Variable parent, ImmutableComponentVariableContent content) {
		this.parent = parent;
		this.content = content;
	}
	
	@Override
	public String getName(ReadGraph graph) throws DatabaseException {
		return content.name;
	}
	
	@Override
	public Variable getParent(ReadGraph graph) throws DatabaseException {
		return parent;
	}
	
	@Override
	public Resource getRepresents(ReadGraph graph) throws DatabaseException {
		return content.resource;
	}

	@Override
	public Variable getPossibleChild(ReadGraph graph, String name) throws DatabaseException {
		if(content.children == null) return null;
		ImmutableComponentVariableContent c = content.children.get(name);
		if(c == null) return null;
		return new ImmutableComponentVariable(this, c);
	}
	
	@Override
	public Collection<Variable> getChildren(ReadGraph graph) throws DatabaseException {
		if(content.children == null) return Collections.emptyList();
		ArrayList<Variable> result = new ArrayList<Variable>(content.children.size());
		for(ImmutableComponentVariableContent c : content.children.values()) {
			result.add(new ImmutableComponentVariable(this, c));
		}
		return result;
	}
	
	@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 new StandardGraphChildVariable(parent, node, content.resource).getPossibleProperty(graph, name);
		
	}
	
	@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;
		
	}
	
}