Add mock phoenixd service

Author: tcheeric

cashu-gateway-phoenixd/src/main/java/xyz/tcheeric/gateway/phoenixd/service/PhoenixdMockServiceImpl.java

@@ -0,0 +1,33 @@
+package xyz.tcheeric.gateway.phoenixd.service;
+
+import xyz.tcheeric.phoenixd.mock.MockLnServer;
+
+import java.io.IOException;
+
+/**
+ * PhoenixdService implementation that starts a {@link MockLnServer}
+ * and delegates requests to the mock gateway endpoints.
+ */
+public class PhoenixdMockServiceImpl extends PhoenixdServiceImpl {
+
+    private final MockLnServer server;
+
+    public PhoenixdMockServiceImpl() {
+        this(9740);
+    }
+
+    public PhoenixdMockServiceImpl(int port) {
+        server = new MockLnServer(port);
+        System.setProperty("phoenixd.base_url", "http://localhost:" + port);
+        try {
+            server.start();
+        } catch (IOException e) {
+            throw new IllegalStateException("Unable to start MockLnServer", e);
+        }
+    }
+
+    public void stop() {
+        server.stop();
+    }
+}
+

cashu-gateway-phoenixd/src/test/java/xyz/tcheeric/gateway/phoenixd/service/PhoenixdMockServiceImplTest.java

@@ -0,0 +1,27 @@
+package xyz.tcheeric.gateway.phoenixd.service;
+
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+import xyz.tcheeric.phoenixd.model.param.CreateInvoiceParam;
+import xyz.tcheeric.phoenixd.model.response.CreateInvoiceResponse;
+
+/**
+ * Verifies that PhoenixdMockServiceImpl can create an invoice using the mock server.
+ */
+public class PhoenixdMockServiceImplTest {
+
+    /**
+     * Starts the mock server and ensures a non-null response when creating an invoice.
+     */
+    @Test
+    public void testCreateInvoice() {
+        PhoenixdMockServiceImpl service = new PhoenixdMockServiceImpl();
+        CreateInvoiceParam param = new CreateInvoiceParam();
+        param.setAmountSat(1);
+        param.setDescription("test");
+        CreateInvoiceResponse response = service.createInvoice(param);
+        Assertions.assertNotNull(response);
+        service.stop();
+    }
+}
+