FilterManager.java

package net.sourceforge.pmd.eclipse.ui.preferences.br;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import net.sourceforge.pmd.Rule;
import net.sourceforge.pmd.lang.rule.properties.StringProperty;
import net.sourceforge.pmd.util.StringUtil;

/**
 * 
 * @author BrianRemedios
 */
public class FilterManager {

	private String				 newFilterPrefix;
	private final StringProperty filterPropertyDesc;
	
	private Map<String, List<Rule>> rulesByFilterName;
	private Map<Integer, String>	namesByFilterHash;
	

	public FilterManager(StringProperty filterDesc, String filterPrefix) {
		filterPropertyDesc = filterDesc;
		newFilterPrefix = filterPrefix;
	}
	
	public void addFilter(String name, String source) {
		
	}

	public void addFilterFrom(Rule rule) {
		
		if (rulesByFilterName == null) {
			rulesByFilterName = new HashMap<String, List<Rule>>();
			namesByFilterHash = new HashMap<Integer, String>();
		}
		
		String filter = rule.getProperty(filterPropertyDesc);
		if (StringUtil.isEmpty(filter)) return;
		
		filter = filter.trim();
		
		int hashCode = filter.hashCode();
		String name = namesByFilterHash.get(hashCode);
		if (name == null) {
			name = newName();
			namesByFilterHash.put(hashCode, name);
			rulesByFilterName.put(name, new ArrayList<Rule>());
		}
		
		rulesByFilterName.get(name).add(rule);
	}
	
	public void setFilter(String name, Rule rule) {
		
	}
	
	private String newName() {
		return newFilterPrefix + namesByFilterHash.size();
	}
	
	public void setName(String name, String filterSource) {
		int code = filterSource.trim().hashCode();
		namesByFilterHash.put(code, name);
	}

	public String[] names() {
		if (rulesByFilterName == null) return StringUtil.getEmptyStrings();
		return rulesByFilterName.keySet().toArray(new String[rulesByFilterName.size()]);
	}
	
	public int referencesTo(String name) {
		if (rulesByFilterName == null) return 0;
		List<Rule> rules = rulesByFilterName.get(name);
		return rules == null ? 0 : rules.size();
	}

	public void modify(String name, String newSource) {
		
		if (rulesByFilterName == null) return;
		
		String theSource = newSource.trim();
		int hash = theSource.hashCode();
		namesByFilterHash.put(hash, name);
		
		for (Rule rule : rulesByFilterName.get(name)) {
			rule.setProperty(filterPropertyDesc, theSource);
		}
	}
	
	public void rename(String oldName, String newName) {
		// TODO
	}
	
	public void remove(String name) {
		for (Rule rule : rulesByFilterName.get(name)) {
			rule.setProperty(filterPropertyDesc, null);
		}
		rulesByFilterName.remove(name);
		
		int hashKey = 0;	// do a reverse lookup
		for (Map.Entry<Integer, String> entry : namesByFilterHash.entrySet()) {
			if (entry.getValue().equals(name)) {
				hashKey = entry.getKey();
				break;
			}
		}
		
		namesByFilterHash.remove(hashKey);
	}
	
	public void load() {
		
	}
	
	public void save() {
		
	}
}