{{ extends 'global/Page.html' }}
{{ block script }}
    <script>
        $(function () {
            let sliders = $("input.slider"),
                outputs = $('.slider-value'),
                target = js_vars.target;

            let getSlidersCurrValues = function(sliders) {
                let sliders_curr_values = [];
                sliders.each(function() {
                    sliders_curr_values.push(parseInt($(this).val()));
                });
                return sliders_curr_values
            };

            let numCenteredSliders = function(sliders_curr_values) {
                let n = 0;
                $.each(sliders_curr_values, function() {
                    if($(this) === target) {
                        ++n;
                    }
                });
                return n
            };

            let numCenteredSlidersChanged = function(sliders_curr_values) {
                return parseInt($('#sliders_task_centered').html()) !== numCenteredSliders(sliders_curr_values);
            };

            // Disable keyboard
            $(document).on('keydown', function () {
               return false
            });

            // On DOM load, for each slider display current value
            sliders.each(function (i) {
                outputs.eq(i).val(sliders.eq(i).val())
            });

            // On input update displayed value for each slider
            sliders.on('input', function () {
               $(this).next().html($(this).val())
            });

            // On value change, if the slider currently moved is set to target value,
            // get current value for each slider and send them to the server
            // NB: change events happen when the value change AND the input field loses focus/isn't selected anymore
            sliders.on('change', function () {
                let sliders_curr_values = getSlidersCurrValues(sliders);

                if ($(this).val() === String(target)||numCenteredSlidersChanged(sliders_curr_values)) {
                    liveSend(sliders_curr_values)
                }
            })
        });

        // When receive message from the server, update number of centered sliders and bonus earned so far
        function liveRecv(data) {
            $('#sliders_task_centered').html(data.ret_score);
        }
    </script>
{{ endblock }}

{{ block styles }}
    <!--Import style sheet from static folder of the current app-->
    <link rel="stylesheet" type="text/css" href="{{ static 'sliders_task/css/sliders_task.css' }}">
{{ endblock }}

{{ block title }}
{{ endblock }}

{{ block content }}

    <div class="container-fluid text-center pt-3 pb-4">
        <div class="row justify-content-around">
            <div class="col-5 py-md-2 col-border">
                Number of sliders correctly set:
                <span id="sliders_task_centered">{{ ret_score }}</span>
            </div>
        </div>
    </div>

    <!--Use Bootstrap 5 grid system to display sliders in three columns-->
    <div class="container-fluid pe-5">

        <!--Loop through chunks of three sliders-->
        {{ for chunk, offset in sliders }}
            <div class="row no-gutters align-items-center justify-content-between mb-3"
                 style="margin-left: {{ offset }}%; margin-right: -{{ offset }}%;">

                <!--For each slider in the chunk, display the input field with annexed current value-->
                {{ for curr_value in chunk }}
                    <input type="range" min="{{ min }}" max="{{ max }}" value="{{ curr_value }}" class="slider col-2" >
                    <output class="slider-value col-1 pl-2"></output>
                {{ endfor }}
            </div>
        {{ endfor }}
    </div>

{{ endblock }}