/*
 * (c) Copyright IBM Corp. 2000, 2001.
 * All Rights Reserved.
 */
package net.sourceforge.phpdt.internal.ui.text.template;

import java.util.ArrayList;

import net.sourceforge.phpdt.internal.corext.template.ContextType;
import net.sourceforge.phpdt.internal.corext.template.DocumentTemplateContext;
import net.sourceforge.phpdt.internal.corext.template.Template;
import net.sourceforge.phpdt.internal.corext.template.Templates;
import net.sourceforge.phpdt.internal.corext.template.php.CompilationUnitContextType;
import net.sourceforge.phpdt.internal.ui.PHPUiImages;
import net.sourceforge.phpdt.internal.ui.text.java.IPHPCompletionProposal;

import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.IRegion;
import org.eclipse.jface.text.ITextViewer;
import org.eclipse.jface.text.Region;
//import org.eclipse.jdt.internal.ui.text.link.LinkedPositionManager;

public class TemplateEngine {

	/** The context type. */
	private ContextType fContextType;
	/** The result proposals. */
	private ArrayList fProposals= new ArrayList();

	/**
	 * Creates the template engine for a particular context type.
	 * See <code>TemplateContext</code> for supported context types.
	 */
	public TemplateEngine(ContextType contextType) {
	//	Assert.isNotNull(contextType);
		fContextType= contextType;
	}

	/**
	 * Empties the collector.
	 * 
	 * @param viewer the text viewer  
	 * @param unit   the compilation unit (may be <code>null</code>)
	 */
	public void reset() {
		fProposals.clear();
	}

	/**
	 * Returns the array of matching templates.
	 */
	public IPHPCompletionProposal[] getResults() {
		return (IPHPCompletionProposal[]) fProposals.toArray(new IPHPCompletionProposal[fProposals.size()]);
	}

	/**
	 * Inspects the context of the compilation unit around <code>completionPosition</code>
	 * and feeds the collector with proposals.
	 * @param viewer the text viewer
	 * @param completionPosition the context position in the document of the text viewer
	 * @param compilationUnit the compilation unit (may be <code>null</code>)
	 */
	public void complete(ITextViewer viewer, int completionPosition)
  //,ICompilationUnit compilationUnit)
	//hrows JavaModelException
	{
	    IDocument document= viewer.getDocument();
	    
		// prohibit recursion
//		if (LinkedPositionManager.hasActiveManager(document))
//			return;

		if (!(fContextType instanceof CompilationUnitContextType))
			return;
		
		((CompilationUnitContextType) fContextType).setContextParameters(document, completionPosition);//mpilationUnit);
		DocumentTemplateContext context= (DocumentTemplateContext) fContextType.createContext();
		int start= context.getStart();
		int end= context.getEnd();
		IRegion region= new Region(start, end - start);

		Template[] templates= Templates.getInstance().getTemplates();
		for (int i= 0; i != templates.length; i++)
			if (context.canEvaluate(templates[i]))
				fProposals.add(new TemplateProposal(templates[i], context, region, viewer, PHPUiImages.get(PHPUiImages.IMG_OBJS_TEMPLATE))); 
	}

}