document.addEventListener("DOMContentLoaded", () => {

    // elements

    let supplyDescriptionElement = document.getElementById("supplydescription");
    let supplyPriceElement = document.getElementById("supplyprice");

    let supplyFormElement = document.getElementById("supplyform");
    let statusInfoElement = document.getElementById("statusinfo");
    let supplySubmitButton = document.getElementById("supplysubmitbtn");

    // custom submit method

    supplyFormElement.addEventListener("submit", (event) => {

        supplySubmitButton.disabled = true;

        event.preventDefault(); // Don't do the default submit action!

        if (isNaN(parseFloat(supplyPriceElement.value)) || supplyDescriptionElement.value == "") {
            statusInfoElement.innerText = "Please enter a description and price."
            supplySubmitButton.disabled = false;
        }

        let xhr = new XMLHttpRequest();
        let formData = new FormData(supplyFormElement);

        xhr.addEventListener("load", (event) => {

            status_ = event.target.status;
            response_ = event.target.responseText;

            if (status_ == 200 && response_ == "success") {
                statusInfoElement.innerText = "Success.";
                window.location.replace("/");
            }
            else {
                statusInfoElement.classList.add("errortext");
                statusInfoElement.innerText = "An error occured.";
                window.setTimeout(() => { window.location.reload() }, 5000);
            }

        })

        xhr.addEventListener("error", (event) => {
            statusInfoElement.classList.add("errortext");
            statusInfoElement.innerText = "An error occured.";
            window.setTimeout(() => { window.location.reload() }, 5000);
        })

        xhr.open("POST", "/api/supply");
        xhr.send(formData);

    });

})