import moment from 'moment';

/**
 * sdGroupDates directive will group list items by a date provided as a param.
 *
 * Usage:
 * <li ng-repeat="item in items" ng-model="item" sd-group-dates="updated">
 *
 * Params:
 * @scope {object} ngModel
 * @scope {string} sdGroupDates - model field to group by
 */
angular.module('superdesk.core.datetime.groupdates', []).directive('sdGroupDates', [function() {
    var lastDate = null;
    var COMPARE_FORMAT = 'YYYY-M-D';
    var DISPLAY_DATE_FORMAT = 'D. MMMM YYYY';
    var DISPLAY_CDATE_FORMAT = 'D. MMMM';
    var DISPLAY_DAY_FORMAT = 'dddd, ';
    var DISPLAY_TODAY_FORMAT = '[Today], ';

    return {
        require: 'ngModel',
        link: function(scope, element, attrs, ngModel) {
            ngModel.$render = function() {
                var date = moment.utc(ngModel.$viewValue[attrs.sdGroupDates]);

                if (scope.$first || lastDate.format(COMPARE_FORMAT) !== date.format(COMPARE_FORMAT)) {
                    var fdate;
                    var fday;

                    if (moment().format(COMPARE_FORMAT) === date.format(COMPARE_FORMAT)) {
                        fday = date.format(DISPLAY_TODAY_FORMAT);
                    } else {
                        fday = date.format(DISPLAY_DAY_FORMAT);
                    }

                    if (moment().format('YYYY') === date.format('YYYY')) {
                        fdate = date.format(DISPLAY_CDATE_FORMAT);
                    } else {
                        fdate = date.format(DISPLAY_DATE_FORMAT);
                    }
                    element.prepend('<div class="date"><span>' + fday + fdate + '</span></div>');
                    element.addClass('with-date');
                    lastDate = date;
                }
            };
        },
    };
}]);