Import Emojibase data (#35229)

app/javascript/mastodon/features/emoji/normalize.ts

@@ -0,0 +1,135 @@
+// Utility codes
+const VARIATION_SELECTOR_CODE = 0xfe0f;
+const KEYCAP_CODE = 0x20e3;
+
+// Gender codes
+const GENDER_FEMALE_CODE = 0x2640;
+const GENDER_MALE_CODE = 0x2642;
+
+// Skin tone codes
+const SKIN_TONE_CODES = [
+  0x1f3fb, // Light skin tone
+  0x1f3fc, // Medium-light skin tone
+  0x1f3fd, // Medium skin tone
+  0x1f3fe, // Medium-dark skin tone
+  0x1f3ff, // Dark skin tone
+] as const;
+
+// Misc codes that have special handling
+const SKIER_CODE = 0x26f7;
+const CHRISTMAS_TREE_CODE = 0x1f384;
+const MR_CLAUS_CODE = 0x1f385;
+const EYE_CODE = 0x1f441;
+const LEVITATING_PERSON_CODE = 0x1f574;
+const SPEECH_BUBBLE_CODE = 0x1f5e8;
+const MS_CLAUS_CODE = 0x1f936;
+
+export function unicodeToTwemojiHex(unicodeHex: string): string {
+  const codes = hexStringToNumbers(unicodeHex);
+  const normalizedCodes: number[] = [];
+  for (let i = 0; i < codes.length; i++) {
+    const code = codes[i];
+    if (!code) {
+      continue;
+    }
+    // Some emoji have their variation selector removed
+    if (code === VARIATION_SELECTOR_CODE) {
+      // Key emoji
+      if (i === 1 && codes.at(-1) === KEYCAP_CODE) {
+        continue;
+      }
+      // Eye in speech bubble
+      if (codes.at(0) === EYE_CODE && codes.at(-2) === SPEECH_BUBBLE_CODE) {
+        continue;
+      }
+    }
+    // This removes zero padding to correctly match the SVG filenames
+    normalizedCodes.push(code);
+  }
+
+  return hexNumbersToString(normalizedCodes, 0);
+}
+
+interface TwemojiSpecificEmoji {
+  unqualified?: string;
+  gender?: number;
+  skin?: number;
+  label?: string;
+}
+
+// Normalize man/woman to male/female
+const GENDER_CODES_MAP: Record<number, number> = {
+  [GENDER_FEMALE_CODE]: GENDER_FEMALE_CODE,
+  [GENDER_MALE_CODE]: GENDER_MALE_CODE,
+  // These are man/woman markers, but are used for gender sometimes.
+  [0x1f468]: GENDER_MALE_CODE,
+  [0x1f469]: GENDER_FEMALE_CODE,
+};
+
+const TWEMOJI_SPECIAL_CASES: Record<string, string | TwemojiSpecificEmoji> = {
+  '1F441-200D-1F5E8': '1F441-FE0F-200D-1F5E8-FE0F', // Eye in speech bubble
+  // An emoji that was never ported to the Unicode standard.
+  // See: https://emojipedia.org/shibuya
+  E50A: { label: 'Shibuya 109' },
+};
+
+export function twemojiToUnicodeInfo(
+  twemojiHex: string,
+): TwemojiSpecificEmoji | string {
+  const specialCase = TWEMOJI_SPECIAL_CASES[twemojiHex.toUpperCase()];
+  if (specialCase) {
+    return specialCase;
+  }
+  const codes = hexStringToNumbers(twemojiHex);
+  let gender: undefined | number;
+  let skin: undefined | number;
+  for (const code of codes) {
+    if (code in GENDER_CODES_MAP) {
+      gender = GENDER_CODES_MAP[code];
+    } else if (code in SKIN_TONE_CODES) {
+      skin = code;
+    }
+  }
+
+  let mappedCodes: unknown[] = codes;
+
+  if (codes.at(-1) === CHRISTMAS_TREE_CODE && codes.length >= 3 && gender) {
+    // Twemoji uses the christmas tree with a ZWJ for Mr. and Mrs. Claus,
+    // but in Unicode that only works for Mx. Claus.
+    const START_CODE =
+      gender === GENDER_FEMALE_CODE ? MS_CLAUS_CODE : MR_CLAUS_CODE;
+    mappedCodes = [START_CODE, skin];
+  } else if (codes.at(-1) === KEYCAP_CODE && codes.length === 2) {
+    // For key emoji, insert the variation selector
+    mappedCodes = [codes[0], VARIATION_SELECTOR_CODE, KEYCAP_CODE];
+  } else if (
+    codes.at(0) === SKIER_CODE ||
+    codes.at(0) === LEVITATING_PERSON_CODE
+  ) {
+    // Twemoji offers more gender and skin options for the skier and levitating person emoji.
+    return {
+      unqualified: hexNumbersToString([codes.at(0)]),
+      skin,
+      gender,
+    };
+  }
+
+  return hexNumbersToString(mappedCodes);
+}
+
+function hexStringToNumbers(hexString: string): number[] {
+  return hexString
+    .split('-')
+    .map((code) => Number.parseInt(code, 16))
+    .filter((code) => !Number.isNaN(code));
+}
+
+function hexNumbersToString(codes: unknown[], padding = 4): string {
+  return codes
+    .filter(
+      (code): code is number =>
+        typeof code === 'number' && code > 0 && !Number.isNaN(code),
+    )
+    .map((code) => code.toString(16).padStart(padding, '0').toUpperCase())
+    .join('-');
+}