/***************************************************************************************************
 * Copyright (c) 2005, 2006 IBM Corporation and others. 
 * All rights reserved. This program and the accompanying materials 
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 * 
 * Contributors: 
 *   IBM Corporation - initial API and implementation
 **************************************************************************************************/
package org.eclipse.jst.jsf.facesconfig.util;

import java.util.List;

import org.eclipse.core.resources.IFile;
import org.eclipse.core.resources.IProject;
import org.eclipse.emf.common.util.URI;
import org.eclipse.emf.ecore.EObject;
import org.eclipse.emf.ecore.resource.Resource;
import org.eclipse.jst.jsf.facesconfig.FacesConfigPlugin;
import org.eclipse.jst.jsf.facesconfig.emf.FacesConfigType;
import org.eclipse.wst.common.componentcore.ArtifactEdit;
import org.eclipse.wst.common.componentcore.internal.ArtifactEditModel;
import org.eclipse.wst.common.componentcore.resources.IVirtualFile;
import org.eclipse.wst.common.componentcore.resources.IVirtualResource;
import org.eclipse.wst.xml.core.internal.emf2xml.EMF2DOMSSERenderer;
import org.eclipse.wst.xml.core.internal.provisional.document.IDOMModel;


/**
 * The artifact edit for the JSF Application Configuration (faces-config) model - may be used but not extended by clients.
 * 
 * This class maybe refactored to a different package in the future.
 */
public final class FacesConfigArtifactEdit extends ArtifactEdit {

	private static final String EDIT_MODEL_ID = "jsf.facesconfig"; //$NON-NLS-1$

	private String sFileName = null;
	private FacesConfigType facesConfig = null;
	private URI facesConfigURI = URI.createURI(IFacesConfigConstants.FACES_CONFIG_URI);
	private boolean bRegistered = false;

	/**
	 * @param aProject
	 * @param toAccessAsReadOnly
	 * @throws IllegalArgumentException
	 */
	public FacesConfigArtifactEdit(IProject aProject, boolean toAccessAsReadOnly) throws IllegalArgumentException {
		super(aProject, toAccessAsReadOnly, false, EDIT_MODEL_ID);
	}

	/**
	 * @param aProject
	 * @param sConfigFile
	 * @return the faces config artifact for the file config file sConfig in project aProject.
	 * Opened only for read access (no write)
	 */
	public static FacesConfigArtifactEdit getFacesConfigArtifactEditForRead(IProject aProject, String sConfigFile) {
		FacesConfigArtifactEdit artifactEdit = null;
		try {
			artifactEdit = new FacesConfigArtifactEdit(aProject, true);
			if (artifactEdit != null) {
				artifactEdit.setFilename(sConfigFile);
			}
		} catch (IllegalArgumentException iae) {
            // suppress illegal argument exception
            FacesConfigPlugin.write(iae);
		}
		return artifactEdit;
	}
	/**
	 * @param aProject
	 * @return the default artifact edit
     * @deprecated Use getFacesConfigArtifactEditForRead(IProject, String) instead. This
     * method is dangerous because the caller is assuming that the "default"
     * model exists and knows nothing about where it is coming from.
	 */
	public static FacesConfigArtifactEdit getFacesConfigArtifactEditForRead(IProject aProject) {
		return getFacesConfigArtifactEditForRead(aProject, null);
	}

    /**
     * @param aProject
     * @param sConfigFile
     * @return the faces config artifact for the file config file sConfig in project aProject.
     * Opened for both write and read access
     */	
	public static FacesConfigArtifactEdit getFacesConfigArtifactEditForWrite(IProject aProject, String sConfigFile) {
		FacesConfigArtifactEdit artifactEdit = null;
		try {
			artifactEdit = new FacesConfigArtifactEdit(aProject, false);
			if (artifactEdit != null) {
				artifactEdit.setFilename(sConfigFile);
			}
		} catch (IllegalArgumentException iae) {
            // suppress illegal argument exception
            FacesConfigPlugin.write(iae);
		}
		return artifactEdit;
	}

	/**
	 * @param aProject
	 * @return the default artifact edit for read
     * @deprecated Use getFacesConfigArtifactEditForWrite(IProject, String) 
     * instead. This method is dangerous because the caller is assuming that
     * the "default" model exists and knows nothing about where it is coming
     * from.
	 */
	public static FacesConfigArtifactEdit getFacesConfigArtifactEditForWrite(IProject aProject) {
		return getFacesConfigArtifactEditForWrite(aProject, null);
	}

	/**
	 * @return the root model object for this artifact edit model
	 */
	public FacesConfigType getFacesConfig() {
		if (facesConfig == null) {
			// TODO: XN - does not seem a good way to check whether the resource has been registered each time.
			// The following comment is from StrutsArchfactEdit:
			// This is a hack to ensure that our Resource.Factory is used to
			// create
			// the Resource. It's the same hack used by JaxRPCMapArtifactEdit.
			// The problem is that there is no way to register a Resource.Factory
			// by, say, content type.
			// The best we can do is register by last file segment, which isn't
			// strictly correct.
			// Plus, there's no way to deregister.
			if (sFileName != null) {
				if (!bRegistered) {
				//if (FacesConfigResourceFactory.getRegisteredFactory(URI.createURI(sFileName)) == null) {
					FacesConfigResourceFactory.register(sFileName);
					bRegistered = true;
				}
			}
			facesConfig = (FacesConfigType)getDeploymentDescriptorRoot(); 
		}
		return facesConfig;
	}
	
	/**
	 * @return the uri pointing to the source of this faces config artifact
	 */
	public URI getFacesConfigURI() {
		return facesConfigURI;
	}

    /**
     * @return the model root
     */
    public EObject getDeploymentDescriptorRoot()
    {
        Resource deploymentDescriptorResource = getDeploymentDescriptorResource();
        if (deploymentDescriptorResource != null)
        {
            List contents = deploymentDescriptorResource.getContents();
            if (contents.size() > 0)
            {
                return (EObject) contents.get(0);
            }
        }
        return null;
        // TODO: XN
        // addFacesConfigIfNecessary((IFacesConfigResource)getDeploymentDescriptorResource());
        // return (EObject) contents.get(0);
    }

	/**
	 * @return the EMF resource retrieved for this artifact's uri or null if
	 * this descriptor has not resource.
	 */
	public Resource getDeploymentDescriptorResource() {
		if (sFileName != null) {
			facesConfigURI = URI.createURI(sFileName);
		} else {// default is "WEB-INF/faces-config.xml"
			facesConfigURI = URI.createURI(IFacesConfigConstants.FACES_CONFIG_URI);
		}
		final ArtifactEditModel artifactEditModel = getArtifactEditModel();
		if (artifactEditModel != null)
		{
		    return artifactEditModel.getResource(facesConfigURI);
		}
		return null;
	}

	/**
	 * Sets an instance's filename, used to create a URI and load a model.
	 * 
	 * @param filename This instance's filename.
	 */
	public void setFilename(String filename) {
		sFileName = filename;
		if (filename != null && filename.length() > 0) {
			facesConfigURI = URI.createURI(filename);
		}
	}

	// TODO: appears to be dead
//	protected void addFacesConfigIfNecessary(TranslatorResource aResource) {
//		//TO: XN - See how to create one if the config file does not exist
//		/*if (aResource != null) {
//		    if(aResource.getContents() == null || aResource.getContents().isEmpty()) {
//		        FacesConfigType facesConfigNew = WebapplicationFactory.eINSTANCE.createWebApp();
//				aResource.getContents().add(facesConfigNew);
//				aResource.setModified(true);
//		    } 
//		    FacesConfigType facesConfig = (FacesConfigType)aResource.getContents().get(0);
//			URI moduleURI = getArtifactEditModel().getModuleURI();
//			try {
//				facesConfig.setDisplayName(StructureEdit.getDeployedName(moduleURI));
//			} catch (UnresolveableURIException e) {
//				//Ignore
//			}
//			aResource.setID(facesConfig, J2EEConstants.WEBAPP_ID);
//	
//			try{
//				aResource.saveIfNecessary();
//			}catch(Exception e){
//				e.printStackTrace();
//			}
//		}*/
//	}

	/**
	 * @return the DOM model for the Struts config. file.
	 */
	public IDOMModel getIDOMModel() {
		// Modeled after SourceNestedEditorPage.getXMLModelFromResource().
		// TODO - XN This is a little hackish because it depends on the resource's
		// renderer being an EMF2DOMSedRenderer (which it is, but that could
		// change).
		Resource resource = getDeploymentDescriptorResource();
		if (resource instanceof IFacesConfigResource) {
			EMF2DOMSSERenderer renderer = (EMF2DOMSSERenderer) 
			    ((IFacesConfigResource)resource).getRenderer();
			return renderer.getXMLModel();
		}
		return null;
	}

	/**
	 * @return the IFile used to load the model or null if none.
	 */
	public IFile getFile() {
		IVirtualResource resource = getComponent().getRootFolder().findMember(facesConfigURI.toString());
		if ((resource != null) && (resource.getType() == IVirtualResource.FILE))
			return ((IVirtualFile) resource).getUnderlyingFile();
		return null;
	}
    
    /**
     * @return true if the underlying model has been disposed
     */
    public boolean isDisposed()
    {
        return getArtifactEditModel().isDisposed();
    }
}