federating my verse (iceshrimp & mastodon API compat, read-only)

src/emoji.js

@@ -0,0 +1,93 @@
+import Instance from './instance.js';
+
+const EMOJI_REGEX = /:[a-z0-9_\-]+:/g;
+
+let emoji_cache = [];
+
+export default class Emoji {
+    name;
+    host;
+    url;
+    width;
+    height;
+
+    static parse(data, host) {
+        const instance = Instance.get_instance();
+        let emoji = null;
+        switch (instance.type) {
+            case Instance.types.ICESHRIMP:
+                emoji = Emoji.#parse_iceshrimp(data);
+                break;
+            case Instance.types.MASTODON:
+                emoji = Emoji.#parse_mastodon(data);
+                break;
+            default:
+                break;
+        }
+        if (emoji !== null) emoji_cache.push(emoji);
+        return emoji;
+    }
+
+    static #parse_iceshrimp(data, host) {
+        let emoji = new Emoji()
+        emoji.name = data.name.substring(1, data.name.search('@'));
+        emoji.host = host;
+        emoji.url = data.url;
+        emoji.width = data.width;
+        emoji.height = data.height;
+        return emoji;
+    }
+
+    static #parse_mastodon(data, host) {
+        let emoji = new Emoji()
+        emoji.name = data.shortcode;
+        emoji.host = host;
+        emoji.url = data.url;
+        emoji.width = data.width;
+        emoji.height = data.height;
+        return emoji;
+    }
+
+    get id() {
+        return this.name + '@' + this.host;
+    }
+}
+
+export function parse_text(text, ignore_instance) {
+    if (!text) return text;
+    
+    let index = text.search(EMOJI_REGEX);
+    if (index === -1) return text;
+    index++;
+
+    // find the emoji name
+    let length = 0;
+    while (index + length < text.length && text[index + length] !== ':') length++;
+    let emoji_name = ':' + text.substring(index, index + length) + ':';
+
+    // does this emoji exist?
+    let emoji;
+    for (let cached in emoji_cache) {
+        if (cached.id === emoji_name) {
+            emoji = cached;
+            break;
+        }
+    }
+
+    if (!emoji) return text.substring(0, index + length) + parse_text(text.substring(index + length));
+
+    // replace emoji code with <img>
+    const img = `<img src="${emoji.url}" class="emoji" width="26" height="26" title=":${emoji_name}:" alt="${emoji_name}">`;
+    return text.substring(0, index - 1) + img +
+        parse(text.substring(index + length + 1), emojis, ignore_instance);
+}
+
+export function parse_one(reaction, emojis) {
+    if (reaction == '❤') return '❤️'; // stupid heart unicode
+    if (!reaction.startsWith(':') || !reaction.endsWith(':')) return reaction;
+    for (let i = 0; i < emojis.length; i++) {
+        if (emojis[i].name == reaction.substring(1, reaction.length - 1))
+            return `<img src="${emojis[i].url}" class="emoji" width="26" height="26" title="${reaction}" alt="${emojis[i].name}">`;
+    }
+    return reaction;
+}