/*******************************************************************************
 * Copyright (c) 2000, 2004 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials 
 * are made available under the terms of the Common Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/cpl-v10.html
 * 
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.team.internal.ccvs.ui.subscriber;

import org.eclipse.compare.CompareConfiguration;
import org.eclipse.core.resources.*;
import org.eclipse.core.runtime.*;
import org.eclipse.jface.preference.PreferencePage;
import org.eclipse.jface.viewers.ILabelDecorator;
import org.eclipse.team.core.TeamException;
import org.eclipse.team.core.synchronize.SyncInfo;
import org.eclipse.team.core.variants.IResourceVariant;
import org.eclipse.team.internal.ccvs.core.*;
import org.eclipse.team.internal.ccvs.core.resources.RemoteFile;
import org.eclipse.team.internal.ccvs.ui.*;
import org.eclipse.team.internal.ccvs.ui.Policy;
import org.eclipse.team.ui.synchronize.*;

/**
 * Superclass for all CVS particpants (workspace, merge and compare)
 */
public class CVSParticipant extends SubscriberParticipant {
	
	/* (non-Javadoc)
	 * @see org.eclipse.team.ui.synchronize.subscribers.SubscriberParticipant#initializeConfiguration(org.eclipse.team.ui.synchronize.ISynchronizePageConfiguration)
	 */
	protected void initializeConfiguration(ISynchronizePageConfiguration configuration) {
		super.initializeConfiguration(configuration);
		// The decorator adds itself to the configuration
		ILabelDecorator labelDecorator = new CVSParticipantLabelDecorator(configuration);
		configuration.addLabelDecorator(labelDecorator);
		configuration.setProperty(ISynchronizePageConfiguration.P_CHANGE_SET_MANAGER, CVSUIPlugin.getPlugin().getChangeSetManager());
	}
	
	/* (non-Javadoc)
     * @see org.eclipse.team.ui.synchronize.SubscriberParticipant#updateLabels(org.eclipse.team.ui.synchronize.ISynchronizeModelElement, org.eclipse.compare.CompareConfiguration, org.eclipse.core.runtime.IProgressMonitor)
     */
    public void prepareCompareInput(ISynchronizeModelElement element, CompareConfiguration config, IProgressMonitor monitor) throws TeamException {
        monitor.beginTask(null, 100);
        deriveBaseContentsFromLocal(element, Policy.subMonitorFor(monitor, 10));
        super.prepareCompareInput(element, config, Policy.subMonitorFor(monitor, 80));
        updateLabelsForCVS(element, config, Policy.subMonitorFor(monitor, 10));
        monitor.done();
    }

    /**
     * Helper method for updating compare editor labels
     */
    protected static void updateLabelsForCVS(ISynchronizeModelElement element, CompareConfiguration config, IProgressMonitor monitor) {
        // Add the author to the remote or base
        if (CVSUIPlugin.getPlugin().getPreferenceStore().getBoolean(ICVSUIConstants.PREF_SHOW_AUTHOR_IN_EDITOR)) {
	        SyncInfo info = getSyncInfo(element);
	        if (info != null) {
	    		final IResourceVariant remote = info.getRemote();
	    		final IResourceVariant base = info.getBase();
	    		String remoteAuthor = null;
	    		if (remote != null && !remote.isContainer()) {
	    		    try {
	                    ILogEntry entry = ((ICVSRemoteFile)remote).getLogEntry(monitor);
	                    remoteAuthor = entry.getAuthor();
	                    config.setRightLabel(Policy.bind("CVSParticipant.0", remote.getContentIdentifier(), remoteAuthor)); //$NON-NLS-1$
	                } catch (TeamException e) {
	                    CVSUIPlugin.log(e);
	                }
	    		}
	    		if (base != null && !base.isContainer()) {
	    		    try {
                        String baseAuthor;
                        if (remoteAuthor != null && remote.getContentIdentifier().equals(base.getContentIdentifier())) {
                            baseAuthor = remoteAuthor;
                        } else {
                            ILogEntry entry = ((ICVSRemoteFile)base).getLogEntry(monitor);
                            baseAuthor = entry.getAuthor();
                        }
                        config.setAncestorLabel(Policy.bind("CVSParticipant.1", base.getContentIdentifier(), baseAuthor)); //$NON-NLS-1$
                    } catch (TeamException e) {
                        CVSUIPlugin.log(e);
                    }
	    		}
	        }
        }
    }
    
	protected static SyncInfo getSyncInfo(ISynchronizeModelElement element) {
	    if (element instanceof IAdaptable) {
		    return (SyncInfo)((IAdaptable)element).getAdapter(SyncInfo.class);
	    }
	    return null;
	}

    /**
     * If the local is not modified and the base matches the local then 
     * cache the local contents as the contents of the base.
     * @param element
     * @throws CoreException
     * @throws TeamException
     */
    public static void deriveBaseContentsFromLocal(ISynchronizeModelElement element, IProgressMonitor monitor) throws TeamException {
        SyncInfo info = getSyncInfo(element);
        if (info == null) 
            return;
        
        // We need a base that is a file and a local that is a file
        IResource local = info.getLocal();
        IResourceVariant base = info.getBase();
        if (base == null || base.isContainer() || local.getType() != IResource.FILE || !local.exists())
            return;
        
        // We can only use the local contents for incoming changes.
        // Outgoing or conflicting changes imply that the local has changed
        if ((info.getKind() & SyncInfo.DIRECTION_MASK) != SyncInfo.INCOMING)
            return;
        
        try {
            RemoteFile remoteFile = (RemoteFile)base;
            if (!remoteFile.isContentsCached())
                (remoteFile).setContents((IFile)local, monitor);
        } catch (CoreException e) {
            if (e.getStatus().getCode() == IResourceStatus.RESOURCE_NOT_FOUND) {
                // The file must have just been deleted
                return;
            }
            throw CVSException.wrapException(e);
        }
    }
    
    /* (non-Javadoc)
     * @see org.eclipse.team.ui.synchronize.AbstractSynchronizeParticipant#getPreferencePages()
     */
    public PreferencePage[] getPreferencePages() {
        return addCVSPreferencePages(super.getPreferencePages());
    }

    public static PreferencePage[] addCVSPreferencePages(PreferencePage[] inheritedPages) {
        PreferencePage[] pages = new PreferencePage[inheritedPages.length + 1];
        for (int i = 0; i < inheritedPages.length; i++) {
            pages[i] = inheritedPages[i];
        }
        pages[pages.length - 1] = new ComparePreferencePage();
        pages[pages.length - 1].setTitle(Policy.bind("CVSParticipant.2")); //$NON-NLS-1$
        return pages;
    }
}