package org.eclipse.osbp.xtext.oxtype.value;

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

import org.eclipse.emf.common.util.URI;
import org.eclipse.emf.ecore.EAttribute;
import org.eclipse.emf.ecore.EObject;
import org.eclipse.emf.ecore.EStructuralFeature;
import org.eclipse.osbp.xtext.oxtype.oxtype.OXImportDeclaration;
import org.eclipse.osbp.xtext.oxtype.oxtype.OXtypeFactory;
import org.eclipse.xtext.naming.QualifiedName;
import org.eclipse.xtext.resource.IResourceServiceProvider;
import org.eclipse.xtext.xtype.XImportDeclaration;
import org.eclipse.xtext.xtype.XImportSection;

public class OXTypeUtil {

	/**
	 * Tries to find the name by a "name" {@link EAttribute}.
	 * 
	 * @param eObject
	 * @return
	 */
	public static String getNameOrNull(EObject eObject) {
		EStructuralFeature nameFeature = eObject.eClass().getEStructuralFeature("name");
		if (nameFeature != null) {
			Object value = eObject.eGet(nameFeature);
			if (value instanceof String) {
				return (String) value;
			}
		}
		return null;
	}

	public static String getImportedName(XImportDeclaration decl) {
		OXImportDeclaration declCustom = (OXImportDeclaration) decl;

		if (declCustom.isWildcard()) {
			return declCustom.getImportedNamespace();
		} else if (declCustom.isFqnImport()) {
			return declCustom.getImportedFullyQualifiedName();
		}

		return declCustom.getImportedName();
	}

	public static List<OXImportDeclaration> getImportDeclarations(XImportSection section) {
		@SuppressWarnings("unchecked")
		List<OXImportDeclaration> result = section != null
				? new ArrayList<OXImportDeclaration>(
						(Collection<? extends OXImportDeclaration>) section.getImportDeclarations())
				: new ArrayList<>();
		return result;
	}

	public static void addFQNImport(XImportSection importSection, QualifiedName fqn) {
		OXImportDeclaration decl = OXtypeFactory.eINSTANCE.createOXImportDeclaration();
		decl.setFqnImport(true);
		decl.setImportedFullyQualifiedName(fqn.toString());
		importSection.getImportDeclarations().add(decl);
	}

	public static void addFQNImportIfNotExists(XImportSection importSection, QualifiedName fqn) {

		// check if already exists
		for (XImportDeclaration decl : importSection.getImportDeclarations()) {
			OXImportDeclaration oDecl = (OXImportDeclaration) decl;
			if (oDecl.isFqnImport() && oDecl.getImportedFullyQualifiedName().equals(fqn.toString())) {
				return;
			}
		}

		OXImportDeclaration decl = OXtypeFactory.eINSTANCE.createOXImportDeclaration();
		decl.setFqnImport(true);
		decl.setImportedFullyQualifiedName(fqn.toString());
		importSection.getImportDeclarations().add(decl);
	}

	public static <T> T makeInstance(String modelExtension, Class<T> clazz) {
		return IResourceServiceProvider.Registry.INSTANCE
				.getResourceServiceProvider(URI.createFileURI("file://my.osbp." + modelExtension)).get(clazz);
	}

}