package org.simantics.structural2.variables;

import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import java.util.Set;

import org.simantics.db.ReadGraph;
import org.simantics.db.Resource;
import org.simantics.db.exception.DatabaseException;
import org.simantics.db.layer0.variable.Variable;
import org.simantics.utils.datastructures.Pair;

import gnu.trove.set.hash.THashSet;

public class FixedConnection implements Connection, Connection2 {

    /*
     * This is the parent of the component to be connected
     */
    final private Variable procedural;
    
    final private Collection<Pair<String,Resource>> cps = new ArrayList<Pair<String,Resource>>();
    
    public FixedConnection(Variable procedural) {
        this.procedural = procedural;
    }
    
    public void addAll(List<Pair<String,Resource>> cps) throws DatabaseException {
        /*
         * For interface connections the name is null
         */
        for(Pair<String,Resource> cp : cps) {
            this.cps.add(cp);
        }
    }
    
    public int size() {
        return cps.size();
    }
    
    public void addConnectionDescriptors(ReadGraph graph, Variable curConfiguration, Collection<VariableConnectionPointDescriptor> result) throws DatabaseException {
        for(Pair<String,Resource> cpzz : cps) {
            // This is a connection to an interface terminal. It is handled by ConnectionBrowser in separate logic. We should never have gotten this far
            if(cpzz.first == null) {
                String message = "Lifted connection was not resolved. Child = " + procedural.getURI(graph);
                throw new DatabaseException(message);
            }
            result.add(new PairConnectionDescriptor(curConfiguration, cpzz));
        }
    }
    
    @Override
    public Collection<Variable> getConnectionPoints(ReadGraph graph, Resource relationType) throws DatabaseException {
        Set<Variable> result = new THashSet<Variable>();
        for(Pair<String,Resource> cp : cps) {
            Variable component = cp.first == null ? procedural : procedural.getChild(graph, cp.first); 
            Variable cp2 = component.getPossibleProperty(graph, cp.second);
            if(cp2 != null)
                for(VariableConnectionPointDescriptor desc : ConnectionBrowser.flatten(graph, component, cp.second, relationType)) {
                    result.add(desc.getVariable(graph));
                }
            else
                StandardProceduralChildVariable.LOGGER.warn("no cp " + cp.first + " for " + component.getURI(graph));
        }
        return result;
    }
    
	@Override
	public Collection<String> getConnectionPointURIs(ReadGraph graph, Resource relationType) throws DatabaseException {
        Set<String> result = new THashSet<String>();
        for(Pair<String,Resource> cp : cps) {
            Variable component = cp.first == null ? procedural : procedural.getChild(graph, cp.first);
            Variable cp2 = component.getPossibleProperty(graph, cp.second);
            if(cp2 != null)
                for(VariableConnectionPointDescriptor desc : ConnectionBrowser.flatten(graph, component, cp.second, relationType)) {
                    result.add(desc.getURI(graph));
                }
            else
                StandardProceduralChildVariable.LOGGER.warn("no cp " + cp.first + " for " + component.getURI(graph));
        }
        return result;
	}
	
	@Override
	public Collection<VariableConnectionPointDescriptor> getConnectionPointDescriptors(ReadGraph graph, Resource relationType) throws DatabaseException {
        Set<VariableConnectionPointDescriptor> result = new THashSet<VariableConnectionPointDescriptor>();
        for(Pair<String,Resource> cp : cps) {
            Variable component = cp.first == null ? procedural : procedural.getChild(graph, cp.first); 
            Variable cp2 = component.getPossibleProperty(graph, cp.second);
            if(cp2 != null)
                result.addAll(ConnectionBrowser.flatten(graph, component, cp.second, relationType));
            else
                StandardProceduralChildVariable.LOGGER.warn("no cp " + cp.first + " for " + component.getURI(graph));
        }
        return result;
	}

    @Override
	public int hashCode() {
		final int prime = 31;
		int result = 1;
		result = prime * result + ((cps == null) ? 0 : cps.hashCode());
		result = prime * result
				+ ((procedural == null) ? 0 : procedural.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;
		FixedConnection other = (FixedConnection) obj;
		if (cps == null) {
			if (other.cps != null)
				return false;
		} else if (!cps.equals(other.cps))
			return false;
		if (procedural == null) {
			if (other.procedural != null)
				return false;
		} else if (!procedural.equals(other.procedural))
			return false;
		return true;
	}

	@Override
	public Collection<VariableConnectionPointDescriptor> getConnectionPointDescriptors(ReadGraph graph,
	        Variable component_, Resource relationType) throws DatabaseException {
        Set<VariableConnectionPointDescriptor> result = new THashSet<VariableConnectionPointDescriptor>();
        for(Pair<String,Resource> cp : cps) {
            Variable component = cp.first == null ? component_.getParent(graph) : component_;
            Variable cp2 = component.getPossibleProperty(graph, cp.second);
            if(cp2 != null)
                result.addAll(ConnectionBrowser.flatten(graph, component, cp.second, relationType));
            else
                StandardProceduralChildVariable.LOGGER.warn("no cp " + cp.first + " for " + component.getURI(graph));
        }
        return result;
	}
	
	@Override
	public Collection<Variable> getConnectionPoints(ReadGraph graph, Variable component_, Resource relationType)
	        throws DatabaseException {
        Set<Variable> result = new THashSet<Variable>();
        for(Pair<String,Resource> cp : cps) {
            Variable component = cp.first == null ? component_.getParent(graph) : component_;
            Variable cp2 = component.getPossibleProperty(graph, cp.second);
            if(cp2 != null)
                for(VariableConnectionPointDescriptor desc : ConnectionBrowser.flatten(graph, component, cp.second, relationType)) {
                    result.add(desc.getVariable(graph));
                }
            else
                StandardProceduralChildVariable.LOGGER.warn("no cp " + cp.first + " for " + component.getURI(graph));
        }
        return result;
	}
	
	@Override
	public Collection<String> getConnectionPointURIs(ReadGraph graph, Variable component_, Resource relationType)
	        throws DatabaseException {
        Set<String> result = new THashSet<String>();
        for(Pair<String,Resource> cp : cps) {
            Variable component = cp.first == null ? component_.getParent(graph) : component_;
            Variable cp2 = component.getPossibleProperty(graph, cp.second);
            if(cp2 != null)
                for(VariableConnectionPointDescriptor desc : ConnectionBrowser.flatten(graph, component, cp.second, relationType)) {
                    result.add(desc.getURI(graph));
                }
            else
                StandardProceduralChildVariable.LOGGER.warn("no cp " + cp.first + " for " + component.getURI(graph));
        }
        return result;
	}

    @Override
    public Connection2 getConnection2() {
        return this;
    }
	
}