How many of the top billed cast are dead?

dedOrNotJellyfin.js

// This is a silly little project created after a friend mentioned a movie and I saw
// that most of the cast photos were black and white. That got me thinking, how many
// of the top billed cast are still alive? Or how many are now dead?
//
// This will use the TMDB API to get the cast list for the movie/tv show
// and then if they're dead, it'll display that.
//
// This is untested, written in little time instead of focussing on other things I should be doing.
//
// No warranty provided. Feel free to do with this what you want.
//
// If you make a Jellyfin plugin to do this please let me know :D 

// INSTRUCTIONS:
// - Get a TMDB API token
// - Get tampermonkey
// - Have Jellyfin
// - Create a tampermonkey script and paste this in the body.
// - Replace the API placeholder with your API key.

'use strict';

const API_ACCESS_KEY_TOKEN = 'REPLACE_THIS_WITH_YOUR_ACCESS_KEY_TOKEN';
const HEADERS = { Authorization: `Bearer ${API_ACCESS_KEY_TOKEN}` };

// Some simple loading/info items that will be put in the media info section for your media.
let dedInfoItem = document.createElement('div');
let dedSkullSpan = document.createElement('span');
let dedSkullLoading = document.createElement('div');

dedSkullSpan.innerHTML = '💀'; // Skull icon.
dedSkullLoading.innerHTML = '⚆'; // Circle with dot right icon.
dedSkullLoading.style.display = 'inline-block'; // We need a div because spans don't animate, but we don't want it to be a block as that wraps to the new line.

dedInfoItem.appendChild(dedSkullSpan);
dedSkullSpan.after(dedSkullLoading);
dedInfoItem.className = 'mediaInfoItem';

// Animate the loading icon while we wait for the info to load.
dedSkullLoading.animate([{ transform: "rotate(360deg)" }], { duration: 2000, iterations: Infinity });

// Don't try query the TMDB API until the cast list is in the DOM.
(new MutationObserver(check)).observe(document, {childList: true, subtree: true});
async function check(changes, observer) {
    // Current class selector for the cast list images (at least the first 15).
    if (document.querySelector('.personCard button.textActionButton')) {
        observer.disconnect();
        // Put the loading icon in the right spot:
        document.querySelector('.mediaInfoItem.mediaInfoCriticRating').after(dedInfoItem);

        // Trigger the code now to get the ded percent :D.
        const movieResults = await getDedResults();

        dedSkullLoading.remove();
        // Show the ratio of ded to not ded.
        dedSkullSpan.after(`${movieResults.ded} / ${movieResults.total}`);
    }
}

async function getActorId(name) {
    // Get the TMDB id for the actor with the given name, just return the first if there are multiple.
    const response = await fetch(`https://api.themoviedb.org/3/search/person?query=${name}`, { headers: HEADERS });
    const data = await response.json();
    const { results } = data;
    if (Array.isArray(results)) {
        return results[0].id;
    }
    // TBH I don't know if I handle this case properly... This was an ADHD project, what you gonna do?
    return null;
};

async function getDed(actorId) {
    // Is the actor ded or not?
    const response = await fetch(`https://api.themoviedb.org/3/person/${actorId}`, { headers: HEADERS });
    const data = await response.json();
    const { deathday } = data;
    return deathday !== null;
};

async function getDedResults() {
    let cast = [];
    let ded = [];

    const castMembers = Array.from(document.querySelectorAll(".personCard button.textActionButton"));
    for (const item of castMembers) {
        const castName = item.innerText;
        if (!castName) {
            continue;
        }
        const actorId = await getActorId(castName);
        if (actorId) {
            cast.push(actorId);
            if (await getDed(actorId)) {
                ded.push(actorId);
            }
        }
    }

    return { ded: ded.length, total: cast.length };
};