CeylonSearchResultContentProvider.java

package com.redhat.ceylon.eclipse.code.search;

import java.util.HashSet;
import java.util.Set;

import org.eclipse.jface.viewers.TableViewer;
import org.eclipse.jface.viewers.Viewer;
import org.eclipse.search.ui.text.AbstractTextSearchResult;
import org.eclipse.swt.widgets.Table;


class CeylonSearchResultContentProvider implements
        CeylonStructuredContentProvider {
    
    private static final Object[] EMPTY_ARR= new Object[0];
    
    private final TableViewer viewer;
    private CeylonSearchResult result;
    private CeylonSearchResultPage page;

    CeylonSearchResultContentProvider(TableViewer viewer, 
            CeylonSearchResultPage page) {
        this.viewer = viewer;
        this.page = page;
    }

    @Override
    public void dispose() {}

    @Override
    public Object[] getElements(Object input) {
        if (input instanceof AbstractTextSearchResult) {
            Set<Object> filteredElements = 
                    new HashSet<Object>();
            AbstractTextSearchResult searchResult = 
                    (AbstractTextSearchResult) input;
            Object[] rawElements = searchResult.getElements();
            int limit = page.getElementLimit().intValue();
            for (int i=0; i<rawElements.length; i++) {
                Object element = rawElements[i];
                if (page.getDisplayedMatchCount(element)>0) {
                    filteredElements.add(element);
                    if (limit!=-1 && 
                            limit<filteredElements.size()) {
                        break;
                    }
                }
            }
            return filteredElements.toArray();
        }
        return EMPTY_ARR;
    }

    @Override
    public void inputChanged(Viewer viewer, 
            Object oldInput, Object newInput) {
        if (newInput instanceof CeylonSearchResult) {
            result = (CeylonSearchResult) newInput;
        }
    }
    
    public void elementsChanged(Object[] updatedElements) {
        if (result!=null) {
            int addLimit = getAddLimit();
            
            Set<Object> updated = new HashSet<Object>();
            Set<Object> added = new HashSet<Object>();
            Set<Object> removed = new HashSet<Object>();
            
            for (int i=0; i<updatedElements.length; i++) {
                Object element = updatedElements[i];
                if (page.getDisplayedMatchCount(element)>0) {
                    if (viewer.testFindItem(element)!=null) {
                        updated.add(element);
                    }
                    else {
                        if (addLimit>0) {
                            added.add(element);
                            addLimit--;
                        }
                    }
                }
                else {
                    removed.add(element);
                }
            }
            
            viewer.add(added.toArray());
            viewer.update(updated.toArray(), null);
            viewer.remove(removed.toArray());
        }
    }

    private int getAddLimit() {
        int limit = page.getElementLimit().intValue();
        if (limit!=-1) {
            Table table = (Table) viewer.getControl();
            int itemCount = table.getItemCount();
            if (itemCount>=limit) {
                return 0;
            }
            return limit-itemCount;
        }
        return Integer.MAX_VALUE;
    }

    
    @Override
    public void clear() {
        viewer.refresh();
    }
    
    @Override
    public void setLevel(int grouping) {
        //ignore
    }
    
    @Override
    public void setShowCategories(boolean showCategories) {
        //ignore
    }
    
}