ujilevel JS

 var namapro = document.getElementById("namaProduk").value
if (namapro == "") {
    document.getElementById("button9").style.display = "inline"
    document.getElementById("button6").style.display = "none"
    document.getElementById("button").style.display = "none"
}
kodeproduk   = []
nama         = []
harga        = []
satuan       = []
gambar       = []
kategori     = []
stok         = []

tampil = document.getElementById('tampildata')

function showData() {
    tampil.innerHTML = ""

    for (i = 0; i < nama.length; i++) {
        nodata = i + 1
        tampil.innerHTML += "<tr>" +
            "<th>" + nodata + "</th>" +
            "<td>" + kodeproduk[i] + "</td>" +
            "<td>" + nama[i] + "</td>" +
            "<td>" + kategori[i] + "</td>" +
            "<td id='stock"+ nodata +"'>" + stok[i] + "</td>" +
            "<td><img src=" + gambar[i] + " id='image' width='100' height=110'></td>" +
            "<td>" +
            "<button class='btn btn-warning mr-2' onclick='editdata(" + i +")'>Edit</button>" +
            "<button class='btn-danger btn' onclick='hapusdata(" + i +")'>Hapus</button>"+
            "</td>" +
            "</tr>"
        var stocks = document.getElementById('stock' + nodata + '')
        if (Number(stocks.innerHTML) <= 15) {
            stocks.style.backgroundColor = "red"
            stocks.style.color = "white"
        } else {
            stocks.style.backgroundColor = ""
            stocks.style.color = ""
        }
    }
}

function batal() {
    document.getElementById('kodeProduk').value  = ""
    document.getElementById('namaProduk').value  = ""
    document.getElementById('hargaProduk').value = ""
    document.getElementById('satuan').value      = ""
    document.getElementById('kategori').value    = ""
    document.getElementById('stokAwal').value    = ""
    document.getElementById('urlGambar').value   = ""
    document.getElementById("button9").style.display = "inline"
    document.getElementById("button5").style.display = "none"
    document.getElementById("button").style.display  = "none"
}

function add() {
    var newkode = document.getElementById('kodeProduk').value
    var newnama = document.getElementById('namaProduk').value
    var newharga = document.getElementById('hargaProduk').value
    var newsatuan = document.getElementById('satuan').value
    var newkategori = document.getElementById('kategori').value
    var newstok = document.getElementById('stokAwal').value
    var newgambar = document.getElementById('urlGambar').value

    if (newnama == '') {
        alert('silahkan masukkan data terlebih dahulu!')
    } else {
        kodeproduk.push(newkode)
        nama.push(newnama)
        harga.push(newharga)
        satuan.push(newsatuan)
        gambar.push(newgambar)
        kategori.push(newkategori)
        stok.push(newstok)
        showData()
        document.getElementById('kodeProduk').value = ""
        document.getElementById('namaProduk').value = ""
        document.getElementById('hargaProduk').value = ""
        document.getElementById('satuan').value = ""
        document.getElementById('kategori').value = ""
        document.getElementById('stokAwal').value = ""
        document.getElementById('urlGambar').value = ""
    }
}
var index = []

function editdata(i) {
    document.getElementById('kodeProduk').value = kodeproduk[i]
    document.getElementById('namaProduk').value = nama[i]
    document.getElementById('urlGambar').value = gambar[i]
    document.getElementById('satuan').value = satuan[i]
    document.getElementById('hargaProduk').value = harga[i]
    document.getElementById('kategori').value = kategori[i]
    document.getElementById('stokAwal').value = stok[i]

    document.getElementById("button9").style.display = "none"
    document.getElementById("button6").style.display = "inline"
    document.getElementById("button").style.display = "inline"
    index.push(i)
}

function editSimpan() {
    var newkode = document.getElementById('kodeProduk').value
    var newnama = document.getElementById('namaProduk').value
    var newharga = document.getElementById('hargaProduk').value
    var newsatuan = document.getElementById('satuan').value
    var newkategori = document.getElementById('kategori').value
    var newstok = document.getElementById('stokAwal').value
    var newgambar = document.getElementById('urlGambar').value

    if (newnama == '') {
        alert('silahkan masukkan data terlebih dahulu!')
    } else {
        kodeproduk[index] = newkode
        nama[index] = newnama
        harga[index] = newharga
        satuan[index] = newsatuan
        gambar[index] = newgambar
        kategori[index] = newkategori
        stok[index] = newstok
        showData()
        index.pop()
        document.getElementById('kodeProduk').value = ""
        document.getElementById('namaProduk').value = ""
        document.getElementById('hargaProduk').value = ""
        document.getElementById('satuan').value = ""
        document.getElementById('kategori').value = ""
        document.getElementById('stokAwal').value = ""
        document.getElementById('urlGambar').value = ""
        document.getElementById("button9").style.display = "inline"
        document.getElementById("button6").style.display = "none"
        document.getElementById("button").style.display = "none"
    }
}

function hapusdata(i) {
    if (confirm('apakah kamu yakin ingin menghapus data?')) {
        nama.splice(i, 1);
        kodeproduk.splice(i, 1);
        kategori.splice(i, 1);
        stok.splice(i, 1);
        gambar.splice(i, 1);
        showData()
    }
}

function kodep(value) {
    var idkode = []
    var kodekatagori = value.split(" ").filter(function (e) {
        return e.trim().length > 0;
    });
    for (i = 0; i < kodekatagori.length; i++) {
        if (kodekatagori.length == 1) {
            var code = kodekatagori[i].slice(0, 2)
        } else {
            var code = kodekatagori[i].slice(0, 1)
        }
        idkode.push(code)
    }
    var kodepr = idkode.join("")
    kodepr = kodepr.toUpperCase()
    if (idkode.length == 0) {
        document.getElementById("kodeProduk").value = ''
    } else {
        var count = 1;
        for (i = 0; i < kategori.length; ++i) {
            if (kategori[i].toLowerCase() == value.toLowerCase()) {
                count++;
            }
        }
        if (count < 10) {
            document.getElementById("kodeProduk").value = kodepr + '-00' + count
        } else if (count < 100) {
            document.getElementById("kodeProduk").value = kodepr + '-0' + count
        } else {
            document.getElementById("kodeProduk").value = kodepr + '-' + count
        }
    }
}