source: ComponentRegistry/trunk/ComponentRegistry/src/main/java/clarin/cmdi/componentregistry/CMDComponentSpecExpander.java @ 1562

package clarin.cmdi.componentregistry;

import clarin.cmdi.componentregistry.components.CMDComponentSpec;
import clarin.cmdi.componentregistry.components.CMDComponentType;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashSet;
import java.util.List;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * 
 * @author Twan Goosen <twan.goosen@mpi.nl>
 */
public abstract class CMDComponentSpecExpander {

    private final static Logger LOG = LoggerFactory.getLogger(CMDComponentSpecExpander.class);
    protected final ComponentRegistry registry;

    public CMDComponentSpecExpander(ComponentRegistry registry) {
        this.registry = registry;
    }

    private void expandNestedComponent(List<CMDComponentType> cmdComponents) throws ComponentRegistryException {
        expandNestedComponent(cmdComponents, new HashSet<String>());
    }

    private void expandNestedComponent(List<CMDComponentType> cmdComponents, Collection<String> path) throws ComponentRegistryException {
        List<CMDComponentType> expanded = new ArrayList<CMDComponentType>();
        for (CMDComponentType cmdComponentType : cmdComponents) {
            String componentId = cmdComponentType.getComponentId();
            if (componentId != null) {
                if (path.contains(componentId)) {
                    throw new ComponentRegistryException("Detected recursion in component specification: " + path.toString() + " already contains " + componentId);
                } else {
                    Collection<String> newPath = new HashSet<String>(path);
                    newPath.add(componentId);
                    // Use uncached components and profiles, because we expand and thus change them this change should not be in the cache.
                    CMDComponentSpec spec = getUncachedComponent(componentId);
                    if (spec != null) {
                        CMDComponentType nested = getComponentTypeOfAComponent(spec);
                        expandNestedComponent(nested.getCMDComponent(), newPath);
                        overwriteAttributes(cmdComponentType, nested);
                        expanded.add(nested);
                    } else {
                        // Spec could not be resolved
                        LOG.warn("Could not resolve referenced component with id " + componentId);
                        // Add spec itself, without futher expanding
                        expanded.add(cmdComponentType);
                    }
                }
            } else {
                // No id = embedded component
                expandNestedComponent(cmdComponentType.getCMDComponent(), path);
                expanded.add(cmdComponentType);//no attributes overwritten
            }
        }
        cmdComponents.clear();
        cmdComponents.addAll(expanded);
    }

    private CMDComponentType getComponentTypeOfAComponent(CMDComponentSpec result) {
        List<CMDComponentType> cmdComponents = result.getCMDComponent();
        if (cmdComponents.size() != 1) {
            LOG.error("Internal error: CMDComponentSpec which is not a profile can only have one "
                    + "CMDComponentType (which is the description of the component itself).");
        }
        CMDComponentType cmdComponentType = cmdComponents.get(0);
        return cmdComponentType;
    }

    /**
     * Copying the cardinality specified in the referenceDeclaration over the values in the actual component.
     */
    private void overwriteAttributes(CMDComponentType referenceDeclaration, CMDComponentType nested) {
        if (!referenceDeclaration.getCardinalityMax().isEmpty()) {
            List<String> cardinalityMax = nested.getCardinalityMax();
            cardinalityMax.clear();
            cardinalityMax.addAll(referenceDeclaration.getCardinalityMax());
        }
        if (!referenceDeclaration.getCardinalityMin().isEmpty()) {
            List<String> cardinalityMin = nested.getCardinalityMin();
            cardinalityMin.clear();
            cardinalityMin.addAll(referenceDeclaration.getCardinalityMin());
        }
        nested.setComponentId(referenceDeclaration.getComponentId()); // Setting componentId for better xsd generation.
    }

    protected CMDComponentSpec expandComponent(String componentId) throws ComponentRegistryException {
        // Use uncached components and profiles, because we expand and thus change them this change should not be in the cache.
        CMDComponentSpec result = getUncachedComponent(componentId);//registry.getUncachedComponent(componentId);
        CMDComponentType cmdComponentType = getComponentTypeOfAComponent(result);
        expandNestedComponent(cmdComponentType.getCMDComponent());
        return result;
    }

    protected CMDComponentSpec expandProfile(String profileId) throws ComponentRegistryException {
        // Use uncached components and profiles, because we expand and thus change them this change should not be in the cache.
        CMDComponentSpec result = getUncachedProfile(profileId);//registry.getUncachedProfile(profileId);
        List<CMDComponentType> cmdComponents = result.getCMDComponent();
        expandNestedComponent(cmdComponents);
        return result;
    }

    /**
     * Get uncached component from "this" registry and possibly from public registry. Note: "this" registry can be a user registry.
     * @param componentId
     */
    protected abstract CMDComponentSpec getUncachedComponent(String componentId) throws ComponentRegistryException;

    protected abstract CMDComponentSpec getUncachedProfile(String profileId) throws ComponentRegistryException;
}