// InfoPurchase: highlight the chosen count and show the resulting budget.

(function () {
    var V = window.js_vars || {};
    var budgetPoints = V.budget_points || 0;
    var costPoints = V.cost_points || 0;
    var out = document.getElementById('running-budget-value');
    var nextBtn = document.querySelector('.otree-btn-next');
    if (nextBtn) nextBtn.disabled = true;

    function points(n) {
        return n + (Math.abs(n) === 1 ? ' point' : ' points');
    }

    function update(n) {
        var remaining = Math.max(0, budgetPoints - costPoints * n);
        if (out) {
            out.textContent = points(budgetPoints) + ' − ' + n + ' × ' +
                points(costPoints) + ' = ' + points(remaining);
        }
        if (nextBtn) nextBtn.disabled = false;
    }

    document.querySelectorAll('.reveal-option').forEach(function (label) {
        label.addEventListener('click', function () {
            document.querySelectorAll('.reveal-option').forEach(function (l) {
                l.classList.remove('selected');
            });
            label.classList.add('selected');
            var input = label.querySelector('input[type="radio"]');
            if (input) input.checked = true;
            update(parseInt(input.value, 10) || 0);
        });
    });
})();