Как сделать не активными даты которые прошли

Это фаил Calendar.js

import React, { Component } from "react";
import CalendarDays from "./calendar-days";
import "./Calendar.scss"

export default class Calendar extends Component{
    constructor(){
        super();

        this.weekdays = ['Воскресенье', 'Понидельник', 'Вторник', 'Среда', 'Четверг', 'Пятница', 'Суббота' ];
        this.months = ['Январь', 'Февраль', 'Март', 'Апрель', 'Май', 'Июнь', 'Июль', 'Август', 'Сентябрь', 'Октябырь', 'Ноябырь', 'Декабрь'];

        this.state = {
            currentDay: new Date()
        }
    }
    changeCurrentDay = (day) => {
        this.setState({ currentDay: new Date(day.year, day.month, day.number)});
    }

    render(){
        return(

            <div className="calendar">
                <div className="calendar-header">
                    <h2>{this.months[this.state.currentDay.getMonth()]} {this.state.currentDay.getFullYear()}</h2>
                </div>
                <div className="calendar-body">
                    <div className="table-header">
                        {
                            this.weekdays.map((weekday, index) => {
                                return(
                                    <div key={index}>
                                        <div className="weekday"><p>{weekday}</p></div>
                                    </div>
                                    
                                ) 
                            })
                        }
                    </div>
                    <CalendarDays day={this.state.currentDay} changeCurrentDay={this.changeCurrentDay} />
                </div>
            </div>
        )
    }
}

Это фаил calendar-days.js

function CalendarDays (props){
    let firstDayOfMonth = new Date(props.day.getFullYear(), props.day.getMonth(), 1);
    let weekdayOfFirstDay = firstDayOfMonth.getDay();
    let currentDays = [];
    

    for(let day = 0; day < 42; day++){
        if(day === 0 && weekdayOfFirstDay === 0){
            firstDayOfMonth.setDate(firstDayOfMonth.getDate() - 7);
        } else if( day === 0) {
            firstDayOfMonth.setDate(firstDayOfMonth.getDate() + (day - weekdayOfFirstDay));
        }
         else {
            firstDayOfMonth.setDate(firstDayOfMonth.getDate() + 1);
        }

        let calendarDay = {
            currentMonth: (firstDayOfMonth.getMonth() === props.day.getMonth()),
            date: (new Date(firstDayOfMonth)),
            month: firstDayOfMonth.getMonth(),
            number: firstDayOfMonth.getDate(),
            selected: (firstDayOfMonth.toDateString() === props.day.toDateString()),
            year: firstDayOfMonth.getFullYear()
        }
        currentDays.push(calendarDay);
//console.log(calendarDay)

}
        
  
    

    
    return (
        <div className="table-content">
            {
                currentDays.map((day, index) => {
                    
                    return (
                        <div key={index} className={"calendar-day" + (day.currentMonth ? " current" : "") + (day.selected ? " selected" : "") + (day.currentMonth === false ? " non": "")}
                        onClick={() => props.changeCurrentDay(day)}>
                            
                            <p>{day.number}</p>
                        </div>  
                    )
                })
            }
        </div>
    )
}


export default CalendarDays;