Files
htwkalender-pwa/frontend/src/helpers/ical.ts
2024-06-10 12:00:05 +02:00

139 lines
4.1 KiB
TypeScript

//Calendar implementation for the HTWK Leipzig timetable. Evaluation and display of the individual dates in iCal format.
//Copyright (C) 2024 HTWKalender support@htwkalender.de
//This program is free software: you can redistribute it and/or modify
//it under the terms of the GNU Affero General Public License as published by
//the Free Software Foundation, either version 3 of the License, or
//(at your option) any later version.
//This program is distributed in the hope that it will be useful,
//but WITHOUT ANY WARRANTY; without even the implied warranty of
//MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
//GNU Affero General Public License for more details.
//You should have received a copy of the GNU Affero General Public License
//along with this program. If not, see <https://www.gnu.org/licenses/>.
import ICAL from "ical.js";
import { CalendarComponent } from "ical";
/**
* Interface for the color distinction event
* @param title Event name
* @param color Color code for the event
*/
export interface ColorDistinctionEvent {
summary: string | undefined;
color: string;
}
/**
* Parses iCal data and returns an array of calendar components
* @param icalData iCal data to parse
* @returns Array of calendar components
*/
export function parseICalData(
icalData: string | undefined,
): CalendarComponent[] {
if (icalData === undefined || !icalData) {
return [];
} else {
const jCalData = ICAL.parse(icalData);
const comp = new ICAL.Component(jCalData);
const vEvents = comp.getAllSubcomponents("vevent");
const events: CalendarComponent[] = vEvents.map((vevent: CalendarComponent) => {
return new ICAL.Event(vevent);
});
const colorDistinctionEvents: ColorDistinctionEvent[] = extractedColorizedEvents(events);
return vEvents.map((vevent: CalendarComponent) => {
const event = new ICAL.Event(vevent);
return {
title: event.summary,
start: event.startDate.toJSDate(),
end: event.endDate.toJSDate(),
notes: event.description,
allDay: event.startDate.isDate,
color: colorDistinctionEvents.find(
(e: ColorDistinctionEvent) => e.summary === event.summary,
)?.color,
id: event.uid,
location: event.location,
};
});
}
}
/**
* Extracts the event names and assigns a color to each event
* @param vEvents Array of calendar components
* @returns Array of objects with event name and color
*/
function extractedColorizedEvents(
vEvents: CalendarComponent[],
): ColorDistinctionEvent[] {
return colorizeEvents(filterEventsDistinct(vEvents));
}
/**
* Filters out duplicate events
* @param vEvents Array of calendar components
* @returns Array of calendar components without duplicates
*/
function filterEventsDistinct(
vEvents: CalendarComponent[],
): CalendarComponent[] {
return vEvents.filter(
(vevent: CalendarComponent, index: number, self: CalendarComponent[]) => {
return (
self.findIndex((v) => {
return v.summary === vevent.summary;
}) === index
);
},
);
}
/**
* Assigns a color to each event
* @param vEvents Array of calendar components
* @returns Array of objects with event name and color
*/
function colorizeEvents(vEvents: CalendarComponent[]): ColorDistinctionEvent[] {
return vEvents.map((vevent: CalendarComponent) => {
const colors: string[] = [
"var(--htwk-rot-200)",
"var(--htwk-gruen-300)",
"var(--htwk-magenta-400)",
"var(--htwk-cyan-400)",
"var(--htwk-silbergrau-600)",
"var(--htwk-yellow-300)",
"var(--htwk-blau-300)",
"var(--htwk-dunkelblau-200)",
"var(--htwk-rot-400)",
"var(--htwk-gruen-400)",
"var(--htwk-blau-200)",
];
const randomColor =
colors[
vEvents.findIndex((e: CalendarComponent) => {
return e.summary === vevent.summary;
}) % colors.length
];
return {
summary: vevent.summary,
color: randomColor,
};
});
}
// Exported for testing
export const exportedForTesting = {
extractedColorizedEvents,
filterEventsDistinct,
colorizeEvents,
};