import ngModule from '../../module';
import Component from '../../lib/component';
import './style.scss';

/**
 * Calendar.
 *
 */
export default class Calendar extends Component {
    constructor($element, $scope) {
        super($element, $scope);

        this.defaultDate = new Date();
    }

    get defaultDate() {
        return this._defaultDate;
    }

    set defaultDate(value) {
        this._defaultDate = value;
        this.buildDays();
    }

    get lastDay() {
        let year = this.defaultDate.getYear();
        // Month starts from zero, so we increment one month
        let month = this.defaultDate.getMonth() + 1;

        return new Date(year, month, 0).getDate();
    }

    buildDays() {
        let firstMonthDay = new Date(this.defaultDate);
        firstMonthDay.setDate(1);

        let weekday = firstMonthDay.getDay();

        let year = this.defaultDate.getYear();
        let month = this.defaultDate.getMonth();
        let previousLastMonthDay = new Date(year, month, 0);

        this.days = [];
        let day = 1;

        let previousMonthDay = previousLastMonthDay.getDate() - (weekday - 2);
        let nextMonthDay = 1;

        for (let d = 1; d <= 35; d++) {
            if (d < weekday) {
                let monthDay = new Date(previousLastMonthDay);
                monthDay.setDate(previousMonthDay);
                this.days.push({number: previousMonthDay, date: monthDay, color: 'gray'});
                previousMonthDay++;
            } else if (d >= weekday && day <= this.lastDay) {
                let monthDay = new Date(this.defaultDate);
                monthDay.setDate(day);
                this.days.push({number: day, date: monthDay});
                day++;
            } else if (d >= weekday && day > this.lastDay) {
                this.days.push({number: nextMonthDay, color: 'gray'});
                nextMonthDay++;
            }
        }
    }

    moveNext() {
        let next = this.defaultDate.getMonth() + 1;
        this.defaultDate.setMonth(next);
        this.buildDays();
    }

    movePrevious() {
        let previous = this.defaultDate.getMonth() - 1;
        this.defaultDate.setMonth(previous);
        this.buildDays();
    }

    select(index) {
        this.emit('selection', {value: this.days[index]});
    }

}

Calendar.$inject = ['$element', '$scope', '$attrs'];

ngModule.component('vnCalendar', {
    template: require('./index.html'),
    controller: Calendar,
    bindings: {
        model: '<',
        defaultDate: '<?',
        onSelection: '&?'
    }
});