node-red code to pull calendar and push to eink

calendar2eink.js

// Formats the given Date and returns map with format string parts.
const makeTimeFormatMap = function(date) {
    const tz = Intl.DateTimeFormat().resolvedOptions().locale;
    const dateTimeFormat = new Intl.DateTimeFormat(tz, {
        month: 'short',
        day: 'numeric',
        weekday: 'short',
        hour: 'numeric',
        minute: 'numeric',
        hour12: true,
    });
    const partsMap = {};
    dateTimeFormat.formatToParts(date).map(({type, value}) => {
        partsMap[type] = value
    })
    partsMap.dayPeriod = partsMap.dayPeriod[0].toLowerCase();
    return partsMap;
};

// Makes a Date from a date/time string.
const makeDate = function(dateString) {
    if (dateString.includes("T")) {
        return new Date(dateString);
    }
    // All day events just show up as "YYYY-MM-DD" with no
    // time zone, so parse manually to make sure it's in "local"
    // time zone.
    var b = dateString.split(/\D/);
    return new Date(b[0], b[1]-1, b[2]);
};

// Returns an array of dates between the two time strings.
const getDaysArray = function (start, end) {
    const days = [];
    for (var dt = makeDate(start); dt <= makeDate(end); dt.setDate(dt.getDate() + 1)) {
        days.push(new Date(dt));
    }
    return days;
};

const addEvent = function(events_by_date, date, dateStr, eventValue) {
    events_by_date[date] = events_by_date[date] || {dateStr: dateStr, events: []};
    if (eventValue === null) return;
    events_by_date[date].events.push(eventValue);
};

const today = new Date(new Date().toDateString());
const todayParts = makeTimeFormatMap(today);
const todayStr = `${todayParts.weekday} ${todayParts.month} ${todayParts.day}`;
const by_date = {};
addEvent(by_date, today, todayStr, null);

for (const [calname, cal] of Object.entries(msg.payload)) {
    for (const event of cal.events) {
        const days = getDaysArray(event.start, event.end);
        node.warn(days);
        if (days.length == 1) {
            const ts = days[0];
            const formatParts = makeTimeFormatMap(ts);
            const dateStr = `${formatParts.weekday} ${formatParts.month} ${formatParts.day}`;
            const timeStr =  `${formatParts.hour}:${formatParts.minute}${formatParts.dayPeriod}`;
            const dayDate = new Date(ts.toDateString());
            addEvent(by_date, dayDate, dateStr, timeStr + ' ' + event.summary);
            continue;
        }
        // Multi day events end at midnight the day after, lop it off.
        days.pop();
        for (const day of days) {
            const dayDate = new Date(day.toDateString());
            if (dayDate < today) continue;
            const formatParts = makeTimeFormatMap(day);
            const dateStr = `${formatParts.weekday} ${formatParts.month} ${formatParts.day}`;
            addEvent(by_date, dayDate, dateStr, event.summary);
        }
    }
}

node.warn(by_date);

const drawPayloads = [];
var largeSize = 30;
const sortedByDate = [...Object.keys(by_date)].sort(function (a, b) {
    const x = new Date(a);
    const y = new Date(b);
    return x < y ? -1 : x > y ? 1 : 0;
});
for (const dt of sortedByDate) {
    drawPayloads.push(
    {
        type: "text",
        value: by_date[dt].dateStr,
        font: "ppb.ttf",
        x: 5,
        size: largeSize,
        color: "red"
    });
    largeSize = 25;
    if (by_date[dt].events.length > 0) {
        drawPayloads.push(
        {
            type: "multiline",
            value: by_date[dt].events.join('|'),
            delimiter: '|',
            font: "rbm.ttf",
            offset_y: 30,
            x: 10,
            size: 20,
            y_padding: 5,
            color: "black",
            anchor: "la"
        });
    }
}

node.warn(drawPayloads);

return {payload: drawPayloads };

i´m not so keen in witing programms - i could only use and change some things...
So the flow works great, but i wan´t to change some things to make it more fit for me:
The day are giben in english words: is there a possibility to wirte this in german? The same for 12h and 24h...you comment something in row 25 to 27 about the "local" thinks, but i did not understand what i could change...

and an other question is, if i can impement a second calender

Just updated the script with a few changes I've made that weren't posted. You can add multiple entities to fetch with the calendar.get_events. Here you can see I have both my family calendar and holidays. And yes, you have to add the msg.payload output property now:

For 24 hour time, change hour12: true to hour12: false.

As for the language/locale, I'm not sure how node red pulls that information into the nodejs context, so I don't think I can help there.

Dear Jeff. Thanks a lot for the new skript...the both (or more?) calender words great. I spend now a lot of time in changing the 12h to 24h and the language...after a few hours trying (I´m not a programmer - only a user) I aked chatgpt...and this gave me a simple answer... and now it works perfekt: The only change that is nessesary is in row 3: change the value of "const tz":

here the example (see also the comments for the 12h to 24h-Change):

// Formats the given Date and returns map with format string parts.
const makeTimeFormatMap = function (date) {
const tz = "de-DE"; // Set locale to German
const dateTimeFormat = new Intl.DateTimeFormat(tz, {
month: 'short',
day: 'numeric',
weekday: 'short',
hour: 'numeric',
minute: 'numeric',
hour12: false, // For AM/PM format (can be removed if 24h format is preferred)
});
const partsMap = {};
dateTimeFormat.formatToParts(date).map(({ type, value }) => {
partsMap[type] = value;
});
partsMap.dayPeriod = partsMap.dayPeriod ? partsMap.dayPeriod[0].toLowerCase() : ''; // Adjust for AM/PM
return partsMap;
};

Later I had to adjust the writing: in Germany we do the day first, then the month...

I also had to adjust the size (thats what most people have to do to make it fit to their display) of the text an spaces between the lines because i only use a 1,54" display - i want to mount it into a electric-Socket in the bathroom...

Thanks a lot...