How to set up complex conditions for business process flow ?

opportunityForm.js

if (typeof (MEA) == "undefined") { MEA = {} };
if (typeof (MEA.Opportunity) == "undefined") { MEA.Opportunity = {} };
if (typeof (MEA.Opportunity.OpportunityForm) == "undefined") { MEA.Opportunity.OpportunityForm = {} };

MEA.Opportunity.OpportunityForm = {
    onLoad: function (executionContext) {
        var formContext = executionContext.getFormContext();
        formContext.getAttribute('budgetamount').addOnChange(this.setNeedApproval);
        formContext.getAttribute('mea_riskscode').addOnChange(this.setNeedApproval);
        formContext.getControl('mea_isneedapproval').setDisabled(true);
    },
    setNeedApproval: function (executionContext) {
        var formContext = executionContext.getFormContext();
        var budgetamount = formContext.getAttribute("budgetamount").getValue();
        var risks = formContext.getAttribute("mea_riskscode").getValue();
        //(BUDGETAMOUNT >= 100000 OR (50000 <= BUDGETAMOUNT < 100000 AND (RISK = RISK 1 OR RISK = RISK 2))
        if ((budgetamount >= 100000) || (budgetamount >= 50000 && budgetamount < 100000 && risks!=null && (risks.includes(278490000) || risks.includes(278490001)))){
            formContext.getAttribute('mea_isneedapproval').setValue(true);
            formContext.ui.process.reflow(true);
        }
        else{
            formContext.getAttribute('mea_isneedapproval').setValue(false);
            formContext.ui.process.reflow(true);
        }           
    }
}