/***************************************************************************************************
 * Copyright (c) 2005,2009 Eteration A.S. and Gorkem Ercan. 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: Gorkem Ercan - initial API and implementation
 *               
 **************************************************************************************************/

package org.eclipse.jst.server.generic.internal.xml;

import java.net.URISyntaxException;
import java.net.URL;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import org.eclipse.core.runtime.IConfigurationElement;
import org.eclipse.core.runtime.IExtension;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.Platform;
import org.eclipse.core.runtime.Status;
import org.eclipse.emf.common.util.URI;
import org.eclipse.emf.common.util.WrappedException;
import org.eclipse.emf.ecore.resource.Resource;
import org.eclipse.emf.ecore.resource.ResourceSet;
import org.eclipse.emf.ecore.resource.impl.ResourceSetImpl;
import org.eclipse.jst.server.generic.core.internal.CorePlugin;
import org.eclipse.jst.server.generic.core.internal.Trace;
import org.eclipse.jst.server.generic.internal.core.util.ExtensionPointUtil;
import org.eclipse.jst.server.generic.internal.servertype.definition.ServerTypePackage;
import org.eclipse.jst.server.generic.internal.servertype.definition.util.ServerTypeResourceFactoryImpl;
import org.eclipse.jst.server.generic.servertype.definition.ServerRuntime;
import org.osgi.framework.Bundle;

/**
 * Utility for handling the xml data from .serverdef and .runtimedef files.
 * 
 * @author Gorkem Ercan
 */
public class XMLUtils {

	
    private ArrayList serverDefinitions;
    private ArrayList runtimeDefinitions;


	/**
	 * Constructor
	 */
	public XMLUtils() {
		refresh();
	}

	/**
	 * Load all the serverdefinition and runtimedefinition extensions.
	 */
	private void refresh() {
        serverDefinitions = new ArrayList();
        
        IExtension[] serverDefExtensions = ExtensionPointUtil.getGenericServerDefinitionExtensions();
        
        for (int i = 0; serverDefExtensions != null && i < serverDefExtensions.length; i++) {
            java.net.URI definitionFile = null;
            IExtension extension = serverDefExtensions[i];
            IConfigurationElement[] elements = ExtensionPointUtil.getConfigurationElements(extension);
            
            for (int j = 0; j < elements.length; j++) {
                IConfigurationElement element = elements[j];
                definitionFile = getDefinitionFile(element);
                ServerRuntime runtime = readFile(definitionFile);
                if (runtime != null) {
                    runtime.setId(element.getAttribute("id")); //$NON-NLS-1$
                    runtime.setConfigurationElementNamespace(element.getNamespaceIdentifier());
                    serverDefinitions.add(runtime);
                }
            }
        }

        runtimeDefinitions = new ArrayList();
        
        IExtension[] runtimeDefExtensions = ExtensionPointUtil.getGenericServerRuntimeDefinitionExtensions();
        
        for (int i = 0; runtimeDefExtensions != null && i < runtimeDefExtensions.length; i++) {
            java.net.URI definitionFile = null;
            IExtension extension = runtimeDefExtensions[i];
            IConfigurationElement[] elements = ExtensionPointUtil.getConfigurationElements(extension);
            
            for (int j = 0; j < elements.length; j++) {
                IConfigurationElement element = elements[j];
                definitionFile = getDefinitionFile(element);
                ServerRuntime runtime = readFile(definitionFile);
                if (runtime != null) {
                    runtime.setId(element.getAttribute("id")); //$NON-NLS-1$
                    runtime.setConfigurationElementNamespace(element.getNamespaceIdentifier());
                    runtimeDefinitions.add(runtime);
                }
            }
        }
    }

    private java.net.URI getDefinitionFile(IConfigurationElement element) {
        
        Bundle bundle = Platform.getBundle(element.getNamespaceIdentifier());
        String definitionFile = element.getAttribute("definitionfile"); //$NON-NLS-1$
        Trace.trace(Trace.FINEST,"Loading serverdef file "+definitionFile+" from bundle "+bundle.getSymbolicName()); //$NON-NLS-1$ //$NON-NLS-2$
        
        URL url = bundle.getEntry(definitionFile);
        if (url == null )
        {
            CorePlugin.getDefault().getLog().log( new Status(IStatus.ERROR, CorePlugin.PLUGIN_ID,1,
                    "Definition file "+definitionFile+" can not be resolved in bundle "+ bundle.getSymbolicName() ,null) ); //$NON-NLS-1$ //$NON-NLS-2$
            return null;
        }
		try {
			java.net.URI uri = new java.net.URI(url.toExternalForm());
		    return uri;
		} catch (URISyntaxException e) {
			CorePlugin.getDefault().getLog().log( new Status(IStatus.ERROR, CorePlugin.PLUGIN_ID, 1,
                            "Error loading the definition file", e)); //$NON-NLS-1$
		}
        return null;
    }

    private ServerRuntime readFile(java.net.URI file) {
        // Create a resource set.
        ResourceSet resourceSet = new ResourceSetImpl();

        // Register the default resource factory -- only needed for
        // stand-alone!
        resourceSet.getResourceFactoryRegistry().getExtensionToFactoryMap()
                .put(Resource.Factory.Registry.DEFAULT_EXTENSION,
                        new ServerTypeResourceFactoryImpl());

         ServerTypePackage gstPack = ServerTypePackage.eINSTANCE;

        // Get the URI of the model file.
        URI fileURI = URI.createURI(file.toString());

        // Demand load the resource for this file.
        Resource resource = null;
        try {
            resource = resourceSet.getResource(fileURI, true);
        } catch (WrappedException e) {
            // sth wrong with this .server file.
            CorePlugin.getDefault().getLog().log(
                    new Status(IStatus.ERROR, CorePlugin.PLUGIN_ID, 1,
                            "Error loading the server type definition", e)); //$NON-NLS-1$
        }

        if (resource != null) {
            ServerRuntime def = (ServerRuntime) resource.getContents().get(0);
            if (def != null) {
                def.setFilename(file.toString());
                return def;
            }
        }
        return null;

    }

	/**
	 * @return <code>java.util.List</code> of <code>ServerRuntime</code>s.
	 */
	public List getServerTypeDefinitions() {
		return serverDefinitions;
	}

    /**
     * Get the memory presentation for the .serverdef file
     * @param id
     * @return serverRuntime
     */
    public ServerRuntime getServerTypeDefinition(String id) {
    	Iterator defs = getServerTypeDefinitions().iterator();
        while (id != null && defs.hasNext()) {
            ServerRuntime elem = (ServerRuntime) defs.next();
            if ( elem.getId().equals( id ) )
                return elem;
        }
        return null;
    }

    /**
     * @return <code>java.util.List</code> of <code>ServerRuntime</code>s.
     */
    public List getRuntimeTypeDefinitions() {
        return runtimeDefinitions;
    }

    /**
     * Get the memory presentation for the .runtimedef file
     * @param id
     * @return runtime 
     */
    public ServerRuntime getRuntimeTypeDefinition(String id) {
        Iterator defs = getRuntimeTypeDefinitions().iterator();
        while (defs.hasNext()) {
            ServerRuntime elem = (ServerRuntime) defs.next();
            if ( elem.getId().equals(id) )
                return elem;
        }
        return null;
    }
}