EvenOddExecuter.java

/**
 * Copyright © 2002 Instituto Superior Técnico
 *
 * This file is part of FenixEdu Academic.
 *
 * FenixEdu Academic is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * FenixEdu Academic is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with FenixEdu Academic.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.fenixedu.academic.domain.curricularRules.executors.ruleExecutors;

import org.fenixedu.academic.domain.curricularRules.EvenOddRule;
import org.fenixedu.academic.domain.curricularRules.ICurricularRule;
import org.fenixedu.academic.domain.curricularRules.executors.RuleResult;
import org.fenixedu.academic.domain.enrolment.EnrolmentContext;
import org.fenixedu.academic.domain.enrolment.IDegreeModuleToEvaluate;

public class EvenOddExecuter extends CurricularRuleExecutor {

    @Override
    protected RuleResult executeEnrolmentInEnrolmentEvaluation(ICurricularRule curricularRule,
            IDegreeModuleToEvaluate sourceDegreeModuleToEvaluate, EnrolmentContext enrolmentContext) {
        return RuleResult.createNA(sourceDegreeModuleToEvaluate.getDegreeModule());
    }

    @Override
    protected RuleResult executeEnrolmentVerificationWithRules(ICurricularRule curricularRule,
            IDegreeModuleToEvaluate sourceDegreeModuleToEvaluate, EnrolmentContext enrolmentContext) {
        final EvenOddRule evenOddRule = (EvenOddRule) curricularRule;
        if (!canApplyRule(enrolmentContext, evenOddRule)) {
            return RuleResult.createNA(sourceDegreeModuleToEvaluate.getDegreeModule());
        }

        Integer studentNumber = enrolmentContext.getRegistration().getStudent().getNumber();
        if (evenOddRule.getEven() && isEven(studentNumber) || !evenOddRule.getEven() && isOdd(studentNumber)) {
            return RuleResult.createTrue(sourceDegreeModuleToEvaluate.getDegreeModule());
        }
        return createFalseRuleResult(evenOddRule, sourceDegreeModuleToEvaluate);
    }

    @Override
    protected RuleResult executeEnrolmentWithRulesAndTemporaryEnrolment(ICurricularRule curricularRule,
            IDegreeModuleToEvaluate sourceDegreeModuleToEvaluate, EnrolmentContext enrolmentContext) {
        return executeEnrolmentVerificationWithRules(curricularRule, sourceDegreeModuleToEvaluate, enrolmentContext);
    }

    private RuleResult createFalseRuleResult(final EvenOddRule rule, final IDegreeModuleToEvaluate sourceDegreeModuleToEvaluate) {
        return RuleResult.createFalse(sourceDegreeModuleToEvaluate.getDegreeModule(),
                "curricularRules.ruleExecutors.EvenOddExecutor.invalid.number", rule.getEvenOddString(), rule
                        .getDegreeModuleToApplyRule().getName());
    }

    private boolean isEven(int number) {
        return (number & 1) == 0;
    }

    private boolean isOdd(int number) {
        return (number & 1) != 0;
    }

    @Override
    protected boolean canBeEvaluated(ICurricularRule curricularRule, IDegreeModuleToEvaluate sourceDegreeModuleToEvaluate,
            EnrolmentContext enrolmentContext) {
        return true;
    }

}