+function($) {
    'use strict';

    var modals = $('.modal.multi-step');

    modals.each(function(idx, modal) {
        var $modal = $(modal);
        var $buttons = $modal.find('button.step');
        var total_num_steps = $buttons.length;
        var $progress = $modal.find('.m-progress');
        var $progress_bar = $modal.find('.m-progress-bar');
        var $progress_stats = $modal.find('.m-progress-stats');
        var $progress_current = $modal.find('.m-progress-current');
        var $progress_total = $modal.find('.m-progress-total');
        var $progress_complete  = $modal.find('.m-progress-complete');
        var reset_on_close = $modal.attr('reset-on-close') === 'true';

        function reset() {
            $modal.find('.step').hide();
            $modal.find('[data-step]').hide();
        }

        function completeSteps() {
            $progress_stats.hide();
            $progress_complete.show();
            $modal.find('.progress-text').animate({
                top: '-2em'
            });
            $modal.find('.complete-indicator').animate({
                top: '-2em'
            });
            $progress_bar.addClass('completed');
        }

        function getPercentComplete(current_step, total_steps) {
            return Math.min(current_step / total_steps * 100, 100) + '%';
        }

        function updateProgress(current, total) {
            $progress_bar.animate({
                width: getPercentComplete(current, total)
            });
            if (current - 1 >= total_num_steps) {
                completeSteps();
            } else {
                $progress_current.text(current);
            }

            $progress.find('[data-progress]').each(function() {
                var dp = $(this);
                if (dp.data().progress <= current - 1) {
                    dp.addClass('completed');
                } else {
                    dp.removeClass('completed');
                }
            });
        }

        function goToStep(step) {
            reset();
            var to_show = $modal.find('.step-' + step);
            if (to_show.length === 0) {
                // at the last step, nothing else to show
                return;
            }
            to_show.show();
            var current = parseInt(step, 10);
            updateProgress(current, total_num_steps);
            findFirstFocusableInput(to_show).focus();
        }

        function findFirstFocusableInput(parent) {
            var candidates = [parent.find('input'), parent.find('select'),
                              parent.find('textarea'),parent.find('button')],
                winner = parent;
            $.each(candidates, function() {
                if (this.length > 0) {
                    winner = this[0];
                    return false;
                }
            });
            return $(winner);
        }

        function bindEventsToModal($modal) {
            var data_steps = [];
            $('[data-step]').each(function() {
                var step = $(this).data().step;
                if (step && $.inArray(step, data_steps) === -1) {
                    data_steps.push(step);
                }
            });

            $.each(data_steps, function(i, v) {
                $modal.on('next.m.' + v, {step: v}, function(e) {
                    goToStep(e.data.step);
                });
            });
        }

        function initialize() {
            reset();
            updateProgress(1, total_num_steps);
            $modal.find('.step-1').show();
            $progress_complete.hide();
            $progress_total.text(total_num_steps);
            bindEventsToModal($modal, total_num_steps);
            $modal.data({
                total_num_steps: $buttons.length,
            });
            if (reset_on_close){
                //Bootstrap 2.3.2
                $modal.on('hidden', function () {
                    reset();
                    $modal.find('.step-1').show();
                })
                //Bootstrap 3
                $modal.on('hidden.bs.modal', function () {
                    reset();
                    $modal.find('.step-1').show();
                })
            }
        }

        initialize();
    })
}(jQuery);