package com.onaro.util.jfc.tables.filter;

import com.onaro.sanscreen.client.view.tabular.value.*;
import com.onaro.util.enumeration.*;

import java.util.*;

/**
 * This filter supports filtering based on either enumeration or numeric values.
 * If the pattern matches one of the enumeration names, any rows with that name will pass the filter.
 * Otheriwse, the pattersn of {@link NumberFilter} is supported.
 */
public class NumberEnumFilter extends NumberColumnFilter {
    /**
     * Maps between the name of the enumeration (lowercase) to the enumeration itself
     * When an enum pattern is written in the filter editor, the enumeration is looked for in this map
     */
    private Map<String, EnumPresentation.Attributes> namesToValues = new HashMap<String, EnumPresentation.Attributes>();

    /**
     * Holds patterns that are enumerations (not numbers) 
     */
    private EnumPresentation.Attributes enumPattern = null;


    public NumberEnumFilter(EnumPresentation.Attributes[] enumValues) {
    	
    	if (enumValues == null) return;
    	
        //keeps a mapping between the supported enum names and values
        for (int i = 0; i < enumValues.length; i++) {
            String name = enumValues[i].name.toLowerCase();
            namesToValues.put(name, enumValues[i]);
        }
    }

    protected void parsePattern() throws FilterException{
        super.parsePattern();
        enumPattern = isActive() ? namesToValues.get(pattern.toString().toLowerCase()) : null;
    }

    public boolean isAccepted(Object value) {
        //if the pattern is enum, accept only values with that name
        if (enumPattern != null) {
            return enumPattern.equals(value);
        } else {
            //if the value is a number, pass it to the NumberFilter, otherwise (e.g. enum value when the pattern is not enum) reject.
            return value instanceof NumberValue && super.isAccepted(value);
        }
    }

    //the filter is valid if either enumeration is defined or a valid number filter is defined
    public boolean isValid() {
        return enumPattern != null || super.isValid();
    }
}