Be more explicit about device management

src/main.zig

@@ -413,32 +413,44 @@ pub fn main() !void {
     }
     try stdout.flush();
 
-    if (result.devices.len > 0) {
+    switch (result.devices.len) {
-        const device = result.devices[0];
+        0 => {
-
+            try stderr.print("❌ No devices found for user\n", .{});
-        if (device.serial_id) |sid| {
-            try stdout.print("🔍 Checking recirculation status for {?s}...\n", .{device.device_name});
-            try stdout.flush();
-
-            var status = try getRecirculationStatus(allocator, auth.id_token, sid);
-            defer status.deinit();
-
-            try stdout.print("\n{f}", .{status});
-
-            const recirc_enabled = status.recirculation_enabled orelse false;
-
-            if (recirc_enabled) {
-                try stdout.print("\n✓ Recirculation is already active\n", .{});
-                // Recirculation code commented out as requested
-            } else {
-                // Recirculation code would go here but not called during testing
-                try stdout.print("\n(Recirculation start function available but not called during testing)\n", .{});
-            }
-            try stdout.flush();
-        } else {
-            try stderr.print("❌ No serial_id found for device\n", .{});
             try stderr.flush();
-            return error.NoSerialId;
+            return error.NoDevicesFound;
-        }
+        },
+        1 => {
+            const device = result.devices[0];
+
+            if (device.serial_id) |sid| {
+                try stdout.print("🔍 Checking recirculation status for {?s}...\n", .{device.device_name});
+                try stdout.flush();
+
+                var status = try getRecirculationStatus(allocator, auth.id_token, sid);
+                defer status.deinit();
+
+                try stdout.print("\n{f}", .{status});
+
+                const recirc_enabled = status.recirculation_enabled orelse false;
+
+                if (recirc_enabled) {
+                    try stdout.print("\n✓ Recirculation is already active\n", .{});
+                    // Recirculation code commented out as requested
+                } else {
+                    // Recirculation code would go here but not called during testing
+                    try stdout.print("\n(Recirculation start function available but not called during testing)\n", .{});
+                }
+                try stdout.flush();
+            } else {
+                try stderr.print("❌ No serial_id found for device\n", .{});
+                try stderr.flush();
+                return error.NoSerialId;
+            }
+        },
+        else => {
+            try stderr.print("❌ More than one device found for user, not currently equipped to handle this\n", .{});
+            try stderr.flush();
+            return error.TooManyDevicesFound;
+        },
     }
 }