Basic database structure

- Change license

src/helper/types.ts

@@ -0,0 +1,36 @@
+export enum CryptoUnits {
+    BITCOIN = 'BTC',
+    ETHEREUM = 'ETH',
+    LITECOIN = 'LTC',
+    DOGECOIN = 'DOGE',
+    MONERO = 'XMR'
+}
+
+export enum FiatUnits {
+    USD = 'USD',
+    EUR = 'EURO'
+}
+
+export enum PaymentStatus {
+    /**
+     * The payment has not been yet started. The user did not initiated the transfer.
+     */
+    PENDING = 0,
+
+    /**
+     * The payment has been made but it's not yet confirmed.
+     */
+    UNCONFIRMED = 1,
+
+    /**
+     * The payment is completed and the crypto is now available.
+     */
+    DONE = 2
+}
+
+export interface SellItem {
+    price: {
+        unit: number,
+        currency: 
+    }
+}