[Source Code]-Group data by weekdays in Highchart-Highcharts

const categories = [
            "2021-08-04",
            "2021-08-05",
            "2021-08-06",
            "2021-08-07",
            "2021-08-08",
            "2021-08-09",
            "2021-08-10",
            "2021-08-11",
            "2021-08-12",
            "2021-08-13",
            "2021-08-14",
            "2021-08-15",
            "2021-08-16",
            "2021-08-17",
            "2021-08-18",
            "2021-08-19",
            "2021-08-20",
            "2021-08-21",
            "2021-08-22",
            "2021-08-23",
            "2021-08-24",
            "2021-08-25",
            "2021-08-26",
            "2021-08-27",
            "2021-08-28",
            "2021-08-29",
            "2021-08-30",
            "2021-08-31",
            "2021-09-01",
            "2021-09-02",
            "2021-09-03",
            "2021-09-04",
            "2021-09-05",
            "2021-09-06",
            "2021-09-07",
            "2021-09-08",
            "2021-09-09",
            "2021-09-10",
            "2021-09-11",
            "2021-09-12",
            "2021-09-13",
            "2021-09-14",
            "2021-09-15",
            "2021-09-16",
            "2021-09-17",
            "2021-09-18",
            "2021-09-19",
            "2021-09-20",
            "2021-09-21",
            "2021-09-22",
            "2021-09-23",
            "2021-09-24",
            "2021-09-25",
            "2021-09-26",
            "2021-09-27",
            "2021-09-28",
            "2021-09-29",
            "2021-09-30",
            "2021-10-01",
            "2021-10-02",
            "2021-10-03",
            "2021-10-04",
            "2021-10-05",
            "2021-10-06",
            "2021-10-07",
            "2021-10-08",
            "2021-10-09",
            "2021-10-10",
            "2021-10-11",
            "2021-10-12"]
 const messagesSent = [ 32,
            60,
            71,
            3,
            1,
            25,
            16,
            23,
            28,
            25,
            2,
            1,
            43,
            49,
            32,
            35,
            26,
            2,
            1,
            8,
            36,
            47,
            15,
            20,
            2,
            1,
            2,
            18,
            20,
            30,
            43,
            4,
            4,
            15,
            14,
            48,
            39,
            3,
            2,
            0,
            48,
            34,
            15,
            9,
            1,
            3,
            1,
            85,
            27,
            72,
            11,
            4,
            2,
            0,
            29,
            13,
            21,
            15,
            32,
            2,
            0,
            58,
            37,
            37,
            24,
            5,
            1,
            0,
            0,
            0]
            
            
const messagesReceived = [29,
            79,
            80,
            7,
            2,
            24,
            32,
            23,
            44,
            42,
            3,
            1,
            65,
            69,
            46,
            47,
            23,
            3,
            1,
            28,
            35,
            65,
            22,
            19,
            4,
            1,
            7,
            10,
            32,
            31,
            13,
            8,
            2,
            4,
            48,
            53,
            46,
            7,
            4,
            0,
            48,
            40,
            23,
            18,
            2,
            6,
            2,
            79,
            25,
            86,
            9,
            8,
            5,
            0,
            25,
            18,
            18,
            14,
            37,
            2,
            0,
            52,
            70,
            27,
            25,
            17,
            1,
            0,
            0,
            0]
            
const organizeData = (days, sent, received) => {
  const dayNames = ['Sunday', 'Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday']
  
  // get name of weekday
  const getDayOfWeek = date => {
    const dayOfWeek = new Date(date).getDay();    
    
    return isNaN(dayOfWeek) ? null : dayNames[dayOfWeek];
  }
  
  
  return dayNames.map((dayName) => {
    let correspondingMessagesSent = []
    let correspondingMessagesReceived = []
    
    const matchedDays = days.filter((day, index) => {
      if(dayName === getDayOfWeek(day)) {
        correspondingMessagesSent.push(sent[index])
        correspondingMessagesReceived.push(received[index])
        return day
      }
    })
    
    return { [dayName]: { dates: matchedDays, 
                          sent: correspondingMessagesSent,
                          received: correspondingMessagesReceived} }
  })
}



console.log(organizeData(categories, messagesSent, messagesReceived))

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