import { defaultChartColor } from './theme';
import { GCalendarEvent, GCalendarMeta } from './gapi';
import { PatternEntry } from './pattern';

export type PatternGraphData = {
    name: string,
    value: number,
    color: string
};

export type GraphData = {
    name: string,
    start: Date,
    end: Date,
    data: PatternGraphData[]
};

export async function getGraphData(
        start: Date, end: Date,
        patterns: PatternEntry[], calendars: { [id: string]: GCalendarMeta },
        calEventsGetter: (id: string, start: Date, end: Date) => Promise<GCalendarEvent[]>):
            Promise<{ patternGraphData: PatternGraphData[], calendarGraphData: PatternGraphData[] }> {

    if (start >= end) return { patternGraphData: [], calendarGraphData: [] };
    let event_pms = [];
    for (let id in calendars)
    {
        if (!calendars[id].enabled) continue;
        let filtered = patterns.filter(p => p.cal.regex.test(calendars[id].name));
        if (filtered.length > 0)
            event_pms.push(calEventsGetter(id, start, end)
                .then(r => { return { id, events: r, filtered }; }));
    }
    let all_events = await Promise.all(event_pms);

    let events: {[id: string]: GCalendarEvent[]} = {};
    let patternsByCal: {[id: string]: PatternEntry[]} = {};
    let results: {[idx: number]: number} = {};
    let cal_results: {[id: string]: number} = {};

    all_events.forEach(e => {
        events[e.id] = e.events;
        patternsByCal[e.id] = e.filtered;
    });

    for (let i = 0; i < patterns.length; i++)
        results[i] = 0;
    for (let id in calendars) {
        if (!events[id]) continue;
        events[id].forEach(event => {
            patternsByCal[id].forEach(p => {
                if (!p.event.regex.test(event.summary)) {
                    console.log(event.summary, p.event.regex);
                    return;
                }
                if (!cal_results.hasOwnProperty(id)) {
                    cal_results[id] = 0;
                }
                let duration = (event.end.getTime() - event.start.getTime()) / 60000;
                results[p.idx] += duration;
                cal_results[id] += duration;
            });
        });
    }
    let patternGraphData = [];
    let calendarGraphData = [];
    const filterMarginal = (data: PatternGraphData[]) => {
        let sum = 0;
        let majorParts = [];
        let minorSum = 0;
        data.forEach(d => sum += d.value);
        data.forEach(d => {
            let ratio = d.value / sum;
            if (ratio < 1e-2) minorSum += d.value;
            else majorParts.push(d);
        });
        majorParts.push({
            name: 'Other',
            value: minorSum,
            color: defaultChartColor,
        });
        return majorParts;
    };
    for (let i = 0; i < patterns.length; i++) {
        patternGraphData.push({
            name: patterns[i].name,
            value: results[i] / 60.0,
            color: patterns[i].color.background});
    }
    for (let id in cal_results) {
        calendarGraphData.push({
            name: calendars[id].name,
            value: (cal_results[id] / 60.0),
            color: calendars[id].color.background});
    }
    return {patternGraphData: filterMarginal(patternGraphData),
            calendarGraphData: filterMarginal(calendarGraphData) };
}