{% extends "base.html" %}
{% block content %}
{% include 'includes/warning.html' %}
<!-- Page content -->
<p class="page_title">Select box number to edit</p>
<form action="/boxedit" method = "POST" name="select_box" onsubmit="return validateForm(event);">
<input type="hidden" name="csrf_token" value="{{ csrf_token() }}">
  <div><br>
  <div>
    <div style="padding-left: 8px;">
     <input autofocus id="box_num" type="text" name="box_num" size="5">
    </div>
    <div>
      <button type="submit" class="imps icon-left box_closed">
       Box
      </button>
    </div>
  </div>
</div>
</form>


<script>
// Shared with validateForm()'s submit-time check below.
const valid_numbers = {{available_boxes|tojson}};
const boxNumInput = document.getElementById("box_num");

// LIVE FEEDBACK: red border as soon as the typed number isn't a real,
// in-use box -- same behavior as bybox.html/boxadd.html. Purely
// visual; validateForm() below still does the actual submit-time
// enforcement.
boxNumInput.addEventListener("input", function() {
	const typed = boxNumInput.value;
	if (typed === "") {
		boxNumInput.classList.remove("input-invalid");
		return;
	}
	const typed_num = Number(typed);
	const is_valid = !isNaN(typed) && valid_numbers.includes(typed_num);
	boxNumInput.classList.toggle("input-invalid", !is_valid);
});

function validateForm() {
  let num_input = document.forms["select_box"]["box_num"].value;

  var num_to_check = Number(num_input) ;

  if (num_input == ""){
    //alert("Box number is required");
    showValidationError("You must enter a <br>box number.");
    return false;
  }

  if (isNaN(num_input)){
    showValidationError("Box numbers must <br>be numerals.");
    return false;
  }

  if (valid_numbers.includes(num_to_check)!=1) {
    showValidationError("Box "+num_to_check+" is not in use. <br>Please select a different<br> box number.");

    return false;
  }
}

</script>
{% endblock %}