♻️ Splitted wallet service

DysonNetwork.Wallet/Payment/WalletService.cs

@@ -0,0 +1,50 @@
+using DysonNetwork.Shared.Models;
+using Microsoft.EntityFrameworkCore;
+
+namespace DysonNetwork.Wallet.Payment;
+
+public class WalletService(AppDatabase db)
+{
+    public async Task<SnWallet?> GetWalletAsync(Guid accountId)
+    {
+        return await db.Wallets
+            .Include(w => w.Pockets)
+            .FirstOrDefaultAsync(w => w.AccountId == accountId);
+    }
+
+    public async Task<SnWallet> CreateWalletAsync(Guid accountId)
+    {
+        var existingWallet = await db.Wallets.FirstOrDefaultAsync(w => w.AccountId == accountId);
+        if (existingWallet != null)
+        {
+            throw new InvalidOperationException($"Wallet already exists for account {accountId}");
+        }
+
+        var wallet = new SnWallet { AccountId = accountId };
+
+        db.Wallets.Add(wallet);
+        await db.SaveChangesAsync();
+
+        return wallet;
+    }
+
+    public async Task<(SnWalletPocket wallet, bool isNewlyCreated)> GetOrCreateWalletPocketAsync(
+        Guid walletId,
+        string currency,
+        decimal? initialAmount = null
+    )
+    {
+        var pocket = await db.WalletPockets.FirstOrDefaultAsync(p => p.Currency == currency && p.WalletId == walletId);
+        if (pocket != null) return (pocket, false);
+
+        pocket = new SnWalletPocket
+        {
+            Currency = currency,
+            Amount = initialAmount ?? 0,
+            WalletId = walletId
+        };
+
+        db.WalletPockets.Add(pocket);
+        return (pocket, true);
+    }
+}