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 * and open the template in the editor.
 */

package org.jlab.groot.tree;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import net.objecthunter.exp4j.Expression;
import net.objecthunter.exp4j.ExpressionBuilder;
import net.objecthunter.exp4j.operator.Operator;

/**
 *
 * @author gavalian
 */
public class TreeCut {
    
    String  cutName = "";
    String  cutExpression = "";
    List cutVariables = new ArrayList();
    Expression expr = null;
    private boolean  isCutActive = true;
    
    public ArrayList getBranches(){
    	return (ArrayList) cutVariables;
    }
    
    static Operator operatorGT = new Operator(">", 2, true, Operator.PRECEDENCE_MULTIPLICATION) {
            @Override
            public double apply(final double... args) {
                if(args[0]>args[1]) return 1.0;
                return 0.0;
            }
    };
    
    static Operator operatorLT = new Operator("<", 2, true, Operator.PRECEDENCE_MULTIPLICATION) {
        @Override
        public double apply(final double... args) {
            if(args[0]0.0&&args[1]>0.0) return 1.0;
            return 0.0;
        }
    };
    
    static Operator operatorOR = new Operator("||", 2, true, Operator.PRECEDENCE_ADDITION) {
        @Override
        public double apply(final double... args) {
            if(args[0]>0.0||args[1]>0.0) return 1.0;
            return 0.0;
        }
    };    
    
    public static boolean validateExpression(String expression,  List branches){
    	if(expression.isEmpty()){
    		return false;
    	}
        String[] variables = new String[branches.size()];
        for(int i=0; i < branches.size(); i++) variables[i] = branches.get(i);
        ExpressionBuilder builder = new ExpressionBuilder(expression)
        		.operator(operatorAND)
                .operator(operatorOR)
                .operator(operatorGT)
                .operator(operatorLT)
                .operator(operatorEQ);
        builder.variables(variables);
        try {
            Expression expr = builder.build(); 
        } catch(Exception e){
            return false;
        }
        return true;
    }
    /*
    public DataCut(String name, String exp){
        cutName = name;
        cutExpression = exp;
    }*/
    
    public TreeCut(String name, String exp, List branches){
        cutName       = name;
        cutExpression = exp;
        cutVariables.clear();
        for(String br : branches){
            cutVariables.add(br);
        }
        init();
    }
    
    public boolean isActive(){
        return this.isCutActive;
    }
    
    public void setActive(boolean activeFlag){
        this.isCutActive = activeFlag;
    }
    
    public String getName(){
        return cutName;
    }
    
    public String getExpression(){
        return cutExpression;
    }
    
    public void setExpression(String expression){
    	this.cutExpression = expression;
    	init();
    }
    
    public void setName(String name){
    	this.cutName = name;
    }
    
    final void init(){
        String[] variables = new String[cutVariables.size()];
        for(int i=0; i < variables.length; i++) variables[i] = cutVariables.get(i);
        if(cutExpression.length()>0){
        ExpressionBuilder builder = new ExpressionBuilder(cutExpression)
                .operator(operatorAND)
                .operator(operatorOR)
                .operator(operatorGT)
                .operator(operatorLT)
                .operator(operatorEQ);
        builder.variables(variables);
        expr = builder.build();
        }        
    }
    
    public double isValid(ITree tree){
        if(expr!=null){
        for(int i = 0; i < cutVariables.size(); i++){
            expr.setVariable(cutVariables.get(i), 
                    tree.getBranch(cutVariables.get(i)).getValue().doubleValue());
        }
        	double result = expr.evaluate();
        	//if(result>0.0) return true;
            return result;
        /*}else{
        	return true;
        }*/
    }
        if(this.getExpression()==""){
        	return 1.0;
        }else{
        	return 0.0;
        }
    }
}