let db = null;

export async function initDB() {

    if (db) {
        return db;
    }

    return new Promise((resolve, reject) => {

        const request = indexedDB.open('woordjesDB', 1);

        request.onupgradeneeded = (event) => {

            const database = event.target.result;

            if (!database.objectStoreNames.contains('words')) {
                database.createObjectStore('words', {
                    keyPath: 'key'
                });
            }

            if (!database.objectStoreNames.contains('sync_queue')) {
                database.createObjectStore('sync_queue', {
                    keyPath: 'id',
                    autoIncrement: true
                });
            }

            if (!database.objectStoreNames.contains('session')) {
                database.createObjectStore('session', {
                    keyPath: 'key'
                });
            }
        };

        request.onsuccess = (event) => {
            db = event.target.result;
            resolve(db);
        };

        request.onerror = () => {
            reject(request.error);
        };
    });
}

export function getDB() {
    return db;
}