import {
    addMonths,
    endOfDay,
    endOfMonth,
    endOfQuarter,
    endOfWeek,
    startOfDay,
    startOfMonth,
    startOfQuarter,
    startOfWeek,
    startOfYear,
    subDays,
    subMonths
} from "date-fns";
import format from '../../util/format'

export default () => ({
    range: {
        start: null, end: null
    },
    defaultRange: {
        start: null, end: null
    },
    language: 'en-US',

    init() {
        // console.log('Dates init');

        this.range = {
            start: new Date(window.store.get('start')),
            end: new Date(window.store.get('end'))
        };
        this.defaultRange = {
            start: new Date(window.store.get('start')),
            end: new Date(window.store.get('end'))
        };
        this.language = window.store.get('language');
        this.locale = window.store.get('locale');
        this.locale = 'equal' === this.locale ? this.language : this.locale;
        window.__localeId__ = this.language;
        this.buildDateRange();

        window.store.observe('start', (newValue) => {
            this.range.start = new Date(newValue);
        });
        window.store.observe('end', (newValue) => {
            this.range.end = new Date(newValue);
            this.buildDateRange();
        });

        //this.range = this.setDatesFromViewRange(this.range.start);
        // get values from store and use them accordingly.
        // this.viewRange = window.BasicStore.get('viewRange');
        // this.locale = window.BasicStore.get('locale');
        // this.language = window.BasicStore.get('language');
        // this.locale = 'equal' === this.locale ? this.language : this.locale;
        // window.__localeId__ = this.language;
        //
        // // the range is always null but later on we will store it in BasicStore.
        // if (null === this.range.start && null === this.range.end) {
        //     console.log('start + end = null, calling setDatesFromViewRange()');
        //     this.range = this.setDatesFromViewRange(new Date);
        // }
        // console.log('MainApp: set defaultRange');
        // this.defaultRange = this.setDatesFromViewRange(new Date);
        // // default range is always the current period (initialized ahead)
    },


    buildDateRange() {
        // console.log('Dates buildDateRange');

        // generate ranges
        let nextRange = this.getNextRange();
        let prevRange = this.getPrevRange();
        let last7 = this.lastDays(7);
        let last30 = this.lastDays(30);
        let mtd = this.mtd();
        let ytd = this.ytd();

        // set the title:
        let element = document.getElementsByClassName('daterange-holder')[0];
        element.textContent = format(this.range.start) + ' - ' + format(this.range.end);
        element.setAttribute('data-start', format(this.range.start, 'yyyy-MM-dd'));
        element.setAttribute('data-end', format(this.range.end, 'yyyy-MM-dd'));

        // set the current one
        element = document.getElementsByClassName('daterange-current')[0];
        element.textContent = format(this.defaultRange.start) + ' - ' + format(this.defaultRange.end);
        element.setAttribute('data-start', format(this.defaultRange.start, 'yyyy-MM-dd'));
        element.setAttribute('data-end', format(this.defaultRange.end, 'yyyy-MM-dd'));

        // generate next range
        element = document.getElementsByClassName('daterange-next')[0];
        element.textContent = format(nextRange.start) + ' - ' + format(nextRange.end);
        element.setAttribute('data-start', format(nextRange.start, 'yyyy-MM-dd'));
        element.setAttribute('data-end', format(nextRange.end, 'yyyy-MM-dd'));

        // previous range.
        element = document.getElementsByClassName('daterange-prev')[0];
        element.textContent = format(prevRange.start) + ' - ' + format(prevRange.end);
        element.setAttribute('data-start', format(prevRange.start, 'yyyy-MM-dd'));
        element.setAttribute('data-end', format(prevRange.end, 'yyyy-MM-dd'));

        // last 7
        element = document.getElementsByClassName('daterange-7d')[0];
        element.setAttribute('data-start', format(last7.start, 'yyyy-MM-dd'));
        element.setAttribute('data-end', format(last7.end, 'yyyy-MM-dd'));

        // last 30
        element = document.getElementsByClassName('daterange-90d')[0];
        element.setAttribute('data-start', format(last30.start, 'yyyy-MM-dd'));
        element.setAttribute('data-end', format(last30.end, 'yyyy-MM-dd'));

        // MTD
        element = document.getElementsByClassName('daterange-mtd')[0];
        element.setAttribute('data-start', format(mtd.start, 'yyyy-MM-dd'));
        element.setAttribute('data-end', format(mtd.end, 'yyyy-MM-dd'));

        // YTD
        element = document.getElementsByClassName('daterange-ytd')[0];
        element.setAttribute('data-start', format(ytd.start, 'yyyy-MM-dd'));
        element.setAttribute('data-end', format(ytd.end, 'yyyy-MM-dd'));

        // custom range.
        // console.log('MainApp: buildDateRange end');
    },

    getNextRange() {
        let start = startOfMonth(this.range.start);
        let nextMonth = addMonths(start, 1);
        let end = endOfMonth(nextMonth);
        return {start: nextMonth, end: end};
    },

    getPrevRange() {
        let start = startOfMonth(this.range.start);
        let prevMonth = subMonths(start, 1);
        let end = endOfMonth(prevMonth);
        return {start: prevMonth, end: end};
    },

    ytd() {
        let end = new Date;
        let start = startOfYear(this.range.start);
        return {start: start, end: end};
    },

    mtd() {

        let end = new Date;
        let start = startOfMonth(this.range.start);
        return {start: start, end: end};
    },

    lastDays(days) {
        let end = new Date;
        let start = subDays(end, days);
        return {start: start, end: end};
    },

    changeDateRange(e) {
        e.preventDefault();
        // console.log('MainApp: changeDateRange');
        let target = e.currentTarget;

        let start = new Date(target.getAttribute('data-start'));
        let end = new Date(target.getAttribute('data-end'));
        // console.log('MainApp: Change date range', start, end);

        window.store.set('start', start);
        window.store.set('end', end);
        //this.buildDateRange();
        return false;
    },

});