Localize move notification titles to recipient's preferred language

[Copilot]

Move notifications were hardcoded to English ("${playerName} made a move"). Now they're sent in the recipient's preferred language.

Changes

Cloud Function (functions/index.js)

• Sends notification title with {{name}} token placeholder
• Includes playerName and translationKey in the data payload for client-side translation

Service Worker (public/firebase-messaging-sw.js)

• Added translation loading from locale files for 14 languages (ar, de, el, en, es, fi, fr, he, id, it, ja, nl, tr, zh)
• Detects user's language preference from IndexedDB/localStorage or browser settings
• Uses translationKey from notification data to look up translations generically
• Replaces {{name}} token with playerName from data payload
• Caches loaded translations for performance
• Falls back to English for unknown languages

Locale Files

• Added "moveNotification": "{{name}} <translated text>" to all 14 language files

Example

// Backend sends
notification: { title: '{{name}} made a move' },
data: { playerName: 'John', translationKey: 'moveNotification' }

// Service worker translates using the key
const translatedTitle = translation[translationKey].replace('{{name}}', playerName);
// → "Juan hizo un movimiento" (Spanish)
// → "Yuki さんが動きました" (Japanese)
// → "Pierre a fait un mouvement" (French)

Implementation

Translation is handled client-side in the service worker when background notifications are received:

1. Service worker detects user's language preference
2. Loads appropriate translation file from /locales/{lang}/translation.json
3. Uses translationKey from data to find the translation
4. Replaces {{name}} token with playerName from data
5. Displays translated notification to user

This approach uses token-based translation that can be applied generically to any notification with a matching translation key.

Original prompt

Add translation to the send move notification title based off of the recipients local cow

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[ProLoser]

@copilot ACTUALLY don't do it on the backend in the cloud function, JUST do it on the client or in the webworker

[Copilot]

@copilot ACTUALLY don't do it on the backend in the cloud function, JUST do it on the client or in the webworker

Done! Moved translation logic to the service worker (client-side). The backend Cloud Function is reverted to its original state, and the service worker now handles translating notification titles based on the user's language preference. Commit: 35c3a5a

[ProLoser]

@copilot use a token for the playername and don't check what type of notification it is as we should be applying translation to all notifications when one is available

[Copilot]

Updated! The backend now sends {{name}} token with playerName and translationKey in data. The service worker uses the translationKey to look up the translation and replaces {{name}} with the player name. This generic approach will work for any notification that has a matching translation key. Commit: 6dee5c7