SpecfileElementHyperlinkDetector.java

/*******************************************************************************
 * Copyright (c) 2008, 2017 Alexander Kurtakov.
 * 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:
 *    Alexander Kurtakov - initial API and implementation
 *******************************************************************************/

package org.eclipse.linuxtools.internal.rpm.ui.editor.hyperlink;

import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.eclipse.core.resources.IFile;
import org.eclipse.jface.text.BadLocationException;
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.jface.text.hyperlink.AbstractHyperlinkDetector;
import org.eclipse.jface.text.hyperlink.IHyperlink;
import org.eclipse.linuxtools.internal.rpm.ui.editor.ISpecfileSpecialSymbols;
import org.eclipse.linuxtools.internal.rpm.ui.editor.SpecfileEditor;
import org.eclipse.linuxtools.internal.rpm.ui.editor.parser.SpecfileSource;
import org.eclipse.linuxtools.rpm.ui.editor.parser.Specfile;
import org.eclipse.linuxtools.rpm.ui.editor.parser.SpecfileDefine;
import org.eclipse.linuxtools.rpm.ui.editor.parser.SpecfileElement;
import org.eclipse.linuxtools.rpm.ui.editor.parser.SpecfileParser;
import org.eclipse.ui.IEditorPart;
import org.eclipse.ui.IWorkbench;
import org.eclipse.ui.IWorkbenchPage;
import org.eclipse.ui.IWorkbenchWindow;
import org.eclipse.ui.PlatformUI;
import org.eclipse.ui.part.FileEditorInput;

import com.ibm.icu.util.StringTokenizer;

/**
 * Hyperlink detector for source, patch and defines in the spec file.
 *
 */
public class SpecfileElementHyperlinkDetector extends AbstractHyperlinkDetector {

    private static final String PATCH_IDENTIFIER = "%patch"; //$NON-NLS-1$
    private static final String SOURCE_IDENTIFIER = "%{SOURCE"; //$NON-NLS-1$
    private Specfile specfile;

    @Override
    public IHyperlink[] detectHyperlinks(ITextViewer textViewer,
            IRegion region, boolean canShowMultipleHyperlinks) {

        if (region == null || textViewer == null) {
            return null;
        }

        IDocument document = textViewer.getDocument();
        if (document == null) {
            return null;
        }

        // Keeps the errorHandler on the initial opening of the .spec file
        // otherwise, a new SpecfileParser does not initialize errorHandler
        // until a SpecfileEditor#editorSaved is called
        if (specfile == null) {
			SpecfileEditor a = this.getAdapter(SpecfileEditor.class);
            if (a != null && a.getSpecfile() != null) {
                specfile = a.getSpecfile();
            } else {
                SpecfileParser parser = new SpecfileParser();
                specfile = parser.parse(document);
            }
        }

        int offset = region.getOffset();

        IRegion lineInfo;
        String line;
        try {
            lineInfo = document.getLineInformationOfOffset(offset);
            line = document.get(lineInfo.getOffset(), lineInfo.getLength());
        } catch (BadLocationException ex) {
            return null;
        }

        int offsetInLine = offset - lineInfo.getOffset();

        StringTokenizer tokens = new StringTokenizer(line);
        String word = ""; //$NON-NLS-1$
        int tempLineOffset = 0;
        int wordOffsetInLine = 0;
        while (tokens.hasMoreTokens()) {
            String tempWord = tokens.nextToken();
            Pattern defineRegexp = Pattern.compile("%\\{(.*?)\\}"); //$NON-NLS-1$
            Matcher fit = defineRegexp.matcher(tempWord);
            while (fit.find()){
                if ((fit.start()+tempLineOffset <= offsetInLine) && (offsetInLine <= fit.end()+tempLineOffset)){
                    tempWord = fit.group();
                    wordOffsetInLine = fit.start();
                    tempLineOffset += fit.start();
                    break;
                }
            }
            tempLineOffset += tempWord.length();
            word = tempWord;
            if (tempLineOffset > offsetInLine) {
                break;
            }
        }
        if (word.startsWith(SOURCE_IDENTIFIER)) {
            int sourceNumber = Integer.valueOf(
                    word.substring(SOURCE_IDENTIFIER.length(),
                            word.length() - 1)).intValue();
            SpecfileSource source = specfile.getSource(sourceNumber);
            if (source != null) {
                return prepareHyperlink(lineInfo, line, word, source);
            }
        } else if (word.startsWith(PATCH_IDENTIFIER)) {

            int sourceNumber = Integer.valueOf(
                    word.substring(PATCH_IDENTIFIER.length(), word.length()))
                    .intValue();
            SpecfileSource source = specfile.getPatch(sourceNumber);
            if (source != null) {
                return prepareHyperlink(lineInfo, line, word, source);
            }
        } else {
            String defineName = getDefineName(word);
            SpecfileDefine define = specfile.getDefine(defineName);
            if (define != null) {
                return prepareHyperlink(lineInfo, line, defineName, define,
                        wordOffsetInLine);
            }
        }
        return null;
    }

    private String getDefineName(String word) {
        if (word.startsWith(ISpecfileSpecialSymbols.MACRO_START_LONG)) {
            return word.substring(2, word.length() - 1);
        }
        return ""; //$NON-NLS-1$
    }

    private IHyperlink[] prepareHyperlink(IRegion lineInfo, String line,
            String word, SpecfileElement source, int lineIndex) {
        IRegion urlRegion = new Region(lineInfo.getOffset()
                + line.indexOf(word, lineIndex), word.length());

        // will only work with 1 active page
        // does not work with CompareEditor
        IWorkbench wb = PlatformUI.getWorkbench();
        IWorkbenchWindow win = wb.getActiveWorkbenchWindow();
        IWorkbenchPage page = win.getActivePage();
        IEditorPart editor = page.getActiveEditor();
        // A IFile cannot be retrieve from a IFileStoreEditorInput, so at this time
        // we can only provide this functionality for resources inside the workbench.
        if (editor.getEditorInput() instanceof FileEditorInput) {
            IFile original = ((FileEditorInput) editor.getEditorInput()).getFile();
            return new IHyperlink[] { new SpecfileElementHyperlink(urlRegion,
                    source, original) };
        } else {
            return null;
        }


    }

    private IHyperlink[] prepareHyperlink(IRegion lineInfo, String line,
            String word, SpecfileElement source) {
        return prepareHyperlink(lineInfo, line, word, source, 0);
    }

    public void setSpecfile(Specfile specfile) {
        this.specfile = specfile;
    }
}