import { useCallback } from 'react';
import { environment } from '../../../environments/environment.ts';
import { useHttpService } from '../../../services/HttpService.tsx';
import { formatRange, reportQuery, type ReportComparison, type ReportFilters } from './reportPeriod';

export interface SchedulingCounts {
    scheduled: number;
    completed: number;
    cancelled: number;
    noShow: number;
    other: number;
}

export interface SchedulingReport {
    range: { start: string; end: string };
    compare: ReportComparison;
    locationId?: string;
    timezone: string;
    locations: Array<{ id: string; name: string }>;
    totals: SchedulingCounts;
    weeks: Array<{ start: string; end: string; completed: number; cancelled: number; noShow: number }>;
    byLocation: Array<SchedulingCounts & { locationId?: string; name: string }>;
    comparison: { range: { start: string; end: string }; totals: SchedulingCounts } | null;
}

export const useSchedulingReport = () => {
    const { get } = useHttpService();
    return useCallback(
        (filters: ReportFilters) => get<SchedulingReport>(environment.fhirBaseApi + '/SchedulingReport?' + reportQuery(filters)),
        [get],
    );
};

export const locationLabel = (report: SchedulingReport | undefined, locationId: string) =>
    report?.locations.find((location) => location.id === locationId)?.name ?? 'All locations';

// A spreadsheet reads a leading = + - @ as a formula; location names are typed by the practice.
const cell = (value: string | number) => {
    const text = String(value);
    const safe = /^[=+\-@]/.test(text) ? "'" + text : text;
    return /[",\r\n]/.test(safe) ? '"' + safe.replace(/"/g, '""') + '"' : safe;
};

/** The CSV carries the same numbers the page shows, with the filters that produced them. */
export function schedulingCsv(report: SchedulingReport, locationName: string): string {
    const rows: Array<Array<string | number>> = [
        ['Scheduling & access'],
        ['Period', formatRange(report.range.start, report.range.end)],
        ['Location', locationName],
        ['Time zone', report.timezone],
    ];
    if (report.comparison) {
        rows.push(['Compared with', formatRange(report.comparison.range.start, report.comparison.range.end)]);
    }
    rows.push([]);
    const measures: Array<[string, keyof SchedulingCounts]> = [
        ['Appointments', 'scheduled'],
        ['Completed', 'completed'],
        ['Cancelled', 'cancelled'],
        ['No-show', 'noShow'],
        ['Booked, arrived or checked in', 'other'],
    ];
    rows.push(report.comparison ? ['Measure', 'This period', 'Comparison period'] : ['Measure', 'This period']);
    for (const [label, key] of measures) {
        rows.push(report.comparison ? [label, report.totals[key], report.comparison.totals[key]] : [label, report.totals[key]]);
    }
    rows.push([], ['Week', 'Completed', 'Cancelled', 'No-show']);
    for (const week of report.weeks) {
        rows.push([formatRange(week.start, week.end), week.completed, week.cancelled, week.noShow]);
    }
    rows.push([], ['Location', 'Appointments', 'Completed', 'Cancelled', 'No-show']);
    for (const row of report.byLocation) {
        rows.push([row.name, row.scheduled, row.completed, row.cancelled, row.noShow]);
    }
    return rows.map((row) => row.map(cell).join(',')).join('\r\n') + '\r\n';
}

export const schedulingCsvFilename = (report: SchedulingReport) =>
    'scheduling-report-' + report.range.start + '-to-' + report.range.end + '.csv';