Create more unit tests for USB Devices and Printer Driver (#21)

Reviewed-on: #21
2025-10-21 18:55:32 +00:00
parent d8467b8984
commit 97edea85af
30 changed files with 2441 additions and 92 deletions
--- a/.clangd
+++ b/.clangd
@@ -0,0 +1,11 @@
+---
+If:
+  PathMatch: tests/.*
+CompileFlags:
+  CompilationDatabase: builddir-debug/
+
+---
+If:
+  PathMatch: src/.*
+CompileFlags:
+  CompilationDatabase: builddir/
--- a/.vscode/c_cpp_properties.json
+++ b/.vscode/c_cpp_properties.json
@@ -5,11 +5,12 @@
      "compilerPath": "/usr/bin/clang",
      "cStandard": "c11",
      "cppStandard": "c++20",
-      "compileCommands": "${workspaceFolder}/builddir/compile_commands.json",
      "browse": {
-        "path": ["${workspaceFolder}"]
+        "path": [
+          "${workspaceFolder}"
+        ]
      }
    }
  ],
  "version": 4
-}
+}
--- a/.vscode/settings.json
+++ b/.vscode/settings.json
@@ -1,7 +1,6 @@
 {
  "clangd.arguments": [
    "-background-index",
-    "-compile-commands-dir=builddir/"
  ],
  "editor.formatOnType": false,
  "editor.formatOnSave": true,
--- a/src/core/PrinterService.cpp
+++ b/src/core/PrinterService.cpp
@@ -22,13 +22,19 @@
 #include <spdlog/spdlog.h>

 #include "core/PrinterDriverFactory.hpp"
+#include "libusbwrap/UsbDeviceFactory.hpp"

 namespace ptprnt::core {

-PrinterService::PrinterService() = default;
+// Default constructor delegates to DI constructor
+PrinterService::PrinterService() : PrinterService(std::make_unique<libusbwrap::UsbDeviceFactory>()) {}
+
+// Constructor with dependency injection
+PrinterService::PrinterService(std::unique_ptr<libusbwrap::IUsbDeviceFactory> usbFactory)
+    : mUsbDeviceFactory(std::move(usbFactory)) {}

 bool PrinterService::initialize() {
-    if (!mUsbDeviceFactory.init()) {
+    if (!mUsbDeviceFactory->init()) {
        spdlog::error("Could not initialize libusb");
        return false;
    }
@@ -38,7 +44,7 @@ bool PrinterService::initialize() {
 std::vector<std::shared_ptr<IPrinterDriver>> PrinterService::detectPrinters() {
    spdlog::debug("Detecting printers...");

-    auto usbDevs       = mUsbDeviceFactory.findAllDevices();
+    auto usbDevs       = mUsbDeviceFactory->findAllDevices();
    auto driverFactory = std::make_unique<PrinterDriverFactory>();
    mDetectedPrinters.clear();

--- a/src/core/PrinterService.hpp
+++ b/src/core/PrinterService.hpp
@@ -24,7 +24,7 @@
 #include <vector>

 #include "interface/IPrinterService.hpp"
-#include "libusbwrap/UsbDeviceFactory.hpp"
+#include "libusbwrap/interface/IUsbDeviceFactory.hpp"
 #include "printers/interface/IPrinterDriver.hpp"

 namespace ptprnt::core {
@@ -40,7 +40,12 @@ namespace ptprnt::core {
 */
 class PrinterService : public IPrinterService {
   public:
+    // Default constructor (uses real UsbDeviceFactory)
    PrinterService();
+
+    // Constructor for testing (inject mock factory)
+    explicit PrinterService(std::unique_ptr<libusbwrap::IUsbDeviceFactory> usbFactory);
+
    ~PrinterService() override = default;

    PrinterService(const PrinterService&)            = delete;
@@ -81,7 +86,7 @@ class PrinterService : public IPrinterService {
    bool printLabel(std::unique_ptr<graphics::ILabel> label) override;

   private:
-    libusbwrap::UsbDeviceFactory mUsbDeviceFactory;
+    std::unique_ptr<libusbwrap::IUsbDeviceFactory> mUsbDeviceFactory;
    std::vector<std::shared_ptr<IPrinterDriver>> mDetectedPrinters;
    std::shared_ptr<IPrinterDriver> mCurrentPrinter;
 };
--- a/src/libusbwrap/LibUsbWrapper.cpp
+++ b/src/libusbwrap/LibUsbWrapper.cpp
@@ -0,0 +1,108 @@
+/*
+    ptrnt - print labels on linux
+    Copyright (C) 2025  Moritz Martinius
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+ */
+
+#include "LibUsbWrapper.hpp"
+
+#include "libusb.h"
+
+namespace libusbwrap {
+
+// LibUsbDeviceDeleter
+void LibUsbDeviceDeleter::operator()(libusb_device* dev) const {
+    if (dev && wrapper) {
+        wrapper->unrefDevice(dev);
+    }
+}
+
+// LibUsbWrapper
+
+int LibUsbWrapper::init(libusb_context** ctx) {
+    return libusb_init(ctx);
+}
+
+void LibUsbWrapper::exit(libusb_context* ctx) {
+    libusb_exit(ctx);
+}
+
+ssize_t LibUsbWrapper::getDeviceList(libusb_context* ctx, libusb_device*** list) {
+    return libusb_get_device_list(ctx, list);
+}
+
+void LibUsbWrapper::freeDeviceList(libusb_device** list, int unrefDevices) {
+    libusb_free_device_list(list, unrefDevices);
+}
+
+void LibUsbWrapper::refDevice(libusb_device* dev) {
+    libusb_ref_device(dev);
+}
+
+void LibUsbWrapper::unrefDevice(libusb_device* dev) {
+    libusb_unref_device(dev);
+}
+
+int LibUsbWrapper::getDeviceDescriptor(libusb_device* dev, libusb_device_descriptor* desc) {
+    return libusb_get_device_descriptor(dev, desc);
+}
+
+int LibUsbWrapper::open(libusb_device* dev, libusb_device_handle** handle) {
+    return libusb_open(dev, handle);
+}
+
+void LibUsbWrapper::close(libusb_device_handle* handle) {
+    libusb_close(handle);
+}
+
+int LibUsbWrapper::getSpeed(libusb_device* dev) {
+    return libusb_get_device_speed(dev);
+}
+
+uint8_t LibUsbWrapper::getBusNumber(libusb_device* dev) {
+    return libusb_get_bus_number(dev);
+}
+
+uint8_t LibUsbWrapper::getPortNumber(libusb_device* dev) {
+    return libusb_get_port_number(dev);
+}
+
+int LibUsbWrapper::kernelDriverActive(libusb_device_handle* handle, int interfaceNo) {
+    return libusb_kernel_driver_active(handle, interfaceNo);
+}
+
+int LibUsbWrapper::detachKernelDriver(libusb_device_handle* handle, int interfaceNo) {
+    return libusb_detach_kernel_driver(handle, interfaceNo);
+}
+
+int LibUsbWrapper::claimInterface(libusb_device_handle* handle, int interfaceNo) {
+    return libusb_claim_interface(handle, interfaceNo);
+}
+
+int LibUsbWrapper::releaseInterface(libusb_device_handle* handle, int interfaceNo) {
+    return libusb_release_interface(handle, interfaceNo);
+}
+
+int LibUsbWrapper::bulkTransfer(libusb_device_handle* handle, uint8_t endpoint, unsigned char* data, int length,
+                                int* transferred, unsigned int timeout) {
+    return libusb_bulk_transfer(handle, endpoint, data, length, transferred, timeout);
+}
+
+const char* LibUsbWrapper::errorName(int errorCode) {
+    return libusb_error_name(errorCode);
+}
+
+}  // namespace libusbwrap
--- a/src/libusbwrap/LibUsbWrapper.hpp
+++ b/src/libusbwrap/LibUsbWrapper.hpp
@@ -0,0 +1,125 @@
+/*
+    ptrnt - print labels on linux
+    Copyright (C) 2025  Moritz Martinius
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+ */
+
+#pragma once
+
+#include <cstdint>
+#include <memory>
+
+// Forward declarations to avoid pulling in libusb.h in header
+struct libusb_context;
+struct libusb_device;
+struct libusb_device_handle;
+struct libusb_device_descriptor;
+
+namespace libusbwrap {
+
+// Forward declaration
+class ILibUsbWrapper;
+
+// Custom deleter for libusb_device that uses the wrapper
+struct LibUsbDeviceDeleter {
+    std::shared_ptr<ILibUsbWrapper> wrapper;
+    void operator()(libusb_device* dev) const;
+};
+
+using LibUsbDevicePtr = std::unique_ptr<libusb_device, LibUsbDeviceDeleter>;
+
+/**
+ * @brief Thin wrapper around libusb C API
+ *
+ * This class provides a 1:1 mapping to libusb C functions.
+ */
+class ILibUsbWrapper {
+   public:
+    virtual ~ILibUsbWrapper() = default;
+
+    // Context management (raw pointers - caller manages lifecycle)
+    virtual int init(libusb_context** ctx) = 0;
+    virtual void exit(libusb_context* ctx) = 0;
+
+    // Device enumeration (raw pointers - caller manages lifecycle)
+    virtual ssize_t getDeviceList(libusb_context* ctx, libusb_device*** list) = 0;
+    virtual void freeDeviceList(libusb_device** list, int unrefDevices)       = 0;
+    virtual void refDevice(libusb_device* dev)                                = 0;
+    virtual void unrefDevice(libusb_device* dev)                              = 0;
+
+    // Device descriptor
+    virtual int getDeviceDescriptor(libusb_device* dev, libusb_device_descriptor* desc) = 0;
+
+    // Device opening/closing (raw pointers - caller manages lifecycle)
+    virtual int open(libusb_device* dev, libusb_device_handle** handle) = 0;
+    virtual void close(libusb_device_handle* handle)                    = 0;
+
+    // Device information
+    virtual int getSpeed(libusb_device* dev)          = 0;
+    virtual uint8_t getBusNumber(libusb_device* dev)  = 0;
+    virtual uint8_t getPortNumber(libusb_device* dev) = 0;
+
+    // Kernel driver management
+    virtual int kernelDriverActive(libusb_device_handle* handle, int interfaceNo) = 0;
+    virtual int detachKernelDriver(libusb_device_handle* handle, int interfaceNo) = 0;
+
+    // Interface management
+    virtual int claimInterface(libusb_device_handle* handle, int interfaceNo)   = 0;
+    virtual int releaseInterface(libusb_device_handle* handle, int interfaceNo) = 0;
+
+    // Data transfer
+    virtual int bulkTransfer(libusb_device_handle* handle, uint8_t endpoint, unsigned char* data, int length,
+                             int* transferred, unsigned int timeout) = 0;
+
+    // Error handling
+    virtual const char* errorName(int errorCode) = 0;
+};
+
+/**
+ * @brief Concrete implementation - thin wrapper forwarding to libusb C API
+ */
+class LibUsbWrapper : public ILibUsbWrapper {
+   public:
+    int init(libusb_context** ctx) override;
+    void exit(libusb_context* ctx) override;
+
+    ssize_t getDeviceList(libusb_context* ctx, libusb_device*** list) override;
+    void freeDeviceList(libusb_device** list, int unrefDevices) override;
+    void refDevice(libusb_device* dev) override;
+    void unrefDevice(libusb_device* dev) override;
+
+    int getDeviceDescriptor(libusb_device* dev, libusb_device_descriptor* desc) override;
+
+    int open(libusb_device* dev, libusb_device_handle** handle) override;
+    void close(libusb_device_handle* handle) override;
+
+    int getSpeed(libusb_device* dev) override;
+    uint8_t getBusNumber(libusb_device* dev) override;
+    uint8_t getPortNumber(libusb_device* dev) override;
+
+    int kernelDriverActive(libusb_device_handle* handle, int interfaceNo) override;
+    int detachKernelDriver(libusb_device_handle* handle, int interfaceNo) override;
+
+    int claimInterface(libusb_device_handle* handle, int interfaceNo) override;
+    int releaseInterface(libusb_device_handle* handle, int interfaceNo) override;
+
+    int bulkTransfer(libusb_device_handle* handle, uint8_t endpoint, unsigned char* data, int length, int* transferred,
+                     unsigned int timeout) override;
+
+    const char* errorName(int errorCode) override;
+};
+
+}  // namespace libusbwrap
--- a/src/libusbwrap/UsbDevice.cpp
+++ b/src/libusbwrap/UsbDevice.cpp
@@ -24,44 +24,55 @@

 #include "libusb.h"
 #include "libusbwrap/LibUsbTypes.hpp"
+#include "libusbwrap/LibUsbWrapper.hpp"
 #include "libusbwrap/interface/IUsbDevice.hpp"

 namespace libusbwrap {
-UsbDevice::UsbDevice(libusb_context* ctx, usbDevice_ptr dev) : mLibusbCtx(ctx), mLibusbDev(std::move(dev)) {
-    if (mLibusbCtx == nullptr || mLibusbDev == nullptr) {
-        throw std::invalid_argument("ctx or device are nullptr");
-    }

-    libusb_get_device_descriptor(mLibusbDev.get(), &mLibusbDevDesc);
+// Default constructor delegates to DI constructor
+UsbDevice::UsbDevice(libusb_device* device, const libusb_device_descriptor& desc)
+    : UsbDevice(device, desc, std::make_shared<LibUsbWrapper>()) {}
+
+// Constructor with dependency injection
+UsbDevice::UsbDevice(libusb_device* device, const libusb_device_descriptor& desc,
+                     std::shared_ptr<ILibUsbWrapper> libusbWrapper)
+    : mLibUsb(libusbWrapper), mDevice(device, LibUsbDeviceDeleter{libusbWrapper}), mDeviceDescriptor(desc) {
+    if (!mDevice) {
+        throw std::invalid_argument("device is nullptr");
+    }
 }

 UsbDevice::~UsbDevice() {
-    // only free the device, not the context, which is shared between every device
-    // the UsbDeviceFactory will take care of that
-    if (mIsOpen) {
-        close();
+    if (mIsOpen && mDeviceHandle) {
+        mLibUsb->close(mDeviceHandle);
    }
+    // mDevice auto-deleted by unique_ptr (calls LibUsbDeviceDeleter)
 }

 bool UsbDevice::open() {
-    int openStatus = libusb_open(mLibusbDev.get(), &mLibusbDevHandle);
+    int openStatus = mLibUsb->open(mDevice.get(), &mDeviceHandle);
    if (openStatus != 0) {
        mLastError = static_cast<Error>(openStatus);
        return false;
    }

+    mIsOpen = true;
    return true;
 }

 void UsbDevice::close() {
-    libusb_close(mLibusbDevHandle);
+    if (mDeviceHandle) {
+        mLibUsb->close(mDeviceHandle);
+        mDeviceHandle = nullptr;
+        mIsOpen       = false;
+    }
 }

 bool UsbDevice::detachKernelDriver(int interfaceNo) {
    // TODO: cover the other status codes that can be returned
-    int kernelDriverStatus = libusb_kernel_driver_active(mLibusbDevHandle, interfaceNo);
+    int kernelDriverStatus = mLibUsb->kernelDriverActive(mDeviceHandle, interfaceNo);
    if (kernelDriverStatus == 1) {  // kernel driver is active, we have to detach to continue...
-        int detachStatus = libusb_detach_kernel_driver(mLibusbDevHandle, interfaceNo);
+        int detachStatus = mLibUsb->detachKernelDriver(mDeviceHandle, interfaceNo);
        if (detachStatus != 0) {
            mLastError = static_cast<Error>(detachStatus);
            return false;
@@ -73,7 +84,7 @@ bool UsbDevice::detachKernelDriver(int interfaceNo) {

 bool UsbDevice::claimInterface(int interfaceNo) {
    // TODO: cover the other status codes that can be returned
-    int claimInterfaceStatus = libusb_claim_interface(mLibusbDevHandle, interfaceNo);
+    int claimInterfaceStatus = mLibUsb->claimInterface(mDeviceHandle, interfaceNo);
    if (claimInterfaceStatus != 0) {
        mLastError = static_cast<Error>(claimInterfaceStatus);
        return false;
@@ -82,7 +93,7 @@ bool UsbDevice::claimInterface(int interfaceNo) {
 }

 bool UsbDevice::releaseInterface(int interfaceNo) {
-    int releaseInterfaceStatus = libusb_release_interface(mLibusbDevHandle, interfaceNo);
+    int releaseInterfaceStatus = mLibUsb->releaseInterface(mDeviceHandle, interfaceNo);
    if (releaseInterfaceStatus != 0) {
        mLastError = static_cast<Error>(releaseInterfaceStatus);
        return false;
@@ -92,10 +103,8 @@ bool UsbDevice::releaseInterface(int interfaceNo) {

 bool UsbDevice::bulkTransfer(uint8_t endpoint, const std::vector<uint8_t>& data, int* tx, unsigned int timeout) {
    // TODO: implement error handling for incomplete transactions (tx length != data length)
-    int bulkTransferStatus = 0;
-
-    bulkTransferStatus = libusb_bulk_transfer(mLibusbDevHandle, endpoint, const_cast<unsigned char*>(data.data()),
-                                              data.size(), tx, timeout);
+    int bulkTransferStatus = mLibUsb->bulkTransfer(mDeviceHandle, endpoint, const_cast<unsigned char*>(data.data()),
+                                                   data.size(), tx, timeout);
    if (bulkTransferStatus != 0) {
        mLastError = static_cast<Error>(bulkTransferStatus);
        return false;
@@ -104,19 +113,19 @@ bool UsbDevice::bulkTransfer(uint8_t endpoint, const std::vector<uint8_t>& data,
 }

 const usbId UsbDevice::getUsbId() {
-    return {mLibusbDevDesc.idVendor, mLibusbDevDesc.idProduct};
+    return {mDeviceDescriptor.idVendor, mDeviceDescriptor.idProduct};
 }

 const device::Speed UsbDevice::getSpeed() {
-    return static_cast<device::Speed>(libusb_get_device_speed(mLibusbDev.get()));
+    return static_cast<device::Speed>(mLibUsb->getSpeed(mDevice.get()));
 }

 const uint8_t UsbDevice::getBusNumber() {
-    return libusb_get_bus_number(mLibusbDev.get());
+    return mLibUsb->getBusNumber(mDevice.get());
 }

 const uint8_t UsbDevice::getPortNumber() {
-    return libusb_get_port_number(mLibusbDev.get());
+    return mLibUsb->getPortNumber(mDevice.get());
 }

 const Error UsbDevice::getLastError() {
@@ -124,6 +133,6 @@ const Error UsbDevice::getLastError() {
 }

 const std::string UsbDevice::getLastErrorString() {
-    return std::string(libusb_error_name(static_cast<int>(mLastError)));
+    return std::string(mLibUsb->errorName(static_cast<int>(mLastError)));
 }
 }  // namespace libusbwrap
--- a/src/libusbwrap/UsbDevice.hpp
+++ b/src/libusbwrap/UsbDevice.hpp
@@ -24,23 +24,20 @@

 #include "libusb.h"
 #include "libusbwrap/LibUsbTypes.hpp"
+#include "libusbwrap/LibUsbWrapper.hpp"
 #include "libusbwrap/interface/IUsbDevice.hpp"

 namespace libusbwrap {

-struct usbDevice_deleter {
-    void operator()(libusb_device* dev_ptr) const {
-        if (nullptr != dev_ptr) {
-            libusb_unref_device(dev_ptr);
-        }
-    }
-};
-
-using usbDevice_ptr = std::unique_ptr<libusb_device, usbDevice_deleter>;
-
 class UsbDevice : public IUsbDevice {
   public:
-    explicit UsbDevice(libusb_context* ctx, usbDevice_ptr dev);
+    // Default constructor (uses real LibUsbWrapper)
+    UsbDevice(libusb_device* device, const libusb_device_descriptor& desc);
+
+    // Constructor for testing (inject mock wrapper)
+    UsbDevice(libusb_device* device, const libusb_device_descriptor& desc,
+              std::shared_ptr<ILibUsbWrapper> libusbWrapper);
+
    ~UsbDevice() override;

    // delete copy ctor and assignment
@@ -69,10 +66,13 @@ class UsbDevice : public IUsbDevice {
    const std::string getLastErrorString() override;

   private:
-    libusb_context* mLibusbCtx{nullptr};
-    usbDevice_ptr mLibusbDev{nullptr};
-    libusb_device_handle* mLibusbDevHandle{nullptr};
-    libusb_device_descriptor mLibusbDevDesc{0};
+    std::shared_ptr<ILibUsbWrapper> mLibUsb;  // Injectable wrapper
+
+    // RAII wrappers (UsbDevice owns the lifecycle logic)
+    LibUsbDevicePtr mDevice;                        // unique_ptr with custom deleter
+    libusb_device_handle* mDeviceHandle = nullptr;  // Managed by UsbDevice (calls mLibUsb->close())
+
+    libusb_device_descriptor mDeviceDescriptor{0};
    std::atomic<bool> mIsOpen = false;
    Error mLastError          = Error::SUCCESS;
 };
--- a/src/libusbwrap/UsbDeviceFactory.cpp
+++ b/src/libusbwrap/UsbDeviceFactory.cpp
@@ -27,16 +27,24 @@
 #include <vector>

 #include "libusb.h"
+#include "libusbwrap/LibUsbWrapper.hpp"
 #include "libusbwrap/UsbDevice.hpp"
 #include "libusbwrap/interface/IUsbDevice.hpp"

 namespace libusbwrap {

+// Default constructor delegates to DI constructor
+UsbDeviceFactory::UsbDeviceFactory() : UsbDeviceFactory(std::make_shared<LibUsbWrapper>()) {}
+
+// Constructor with dependency injection
+UsbDeviceFactory::UsbDeviceFactory(std::shared_ptr<ILibUsbWrapper> libusbWrapper) : mLibUsb(std::move(libusbWrapper)) {}
+
 UsbDeviceFactory::~UsbDeviceFactory() {
-    if (mLibusbCtx) {
-        libusb_exit(mLibusbCtx);
+    mDeviceList.clear();  // Release devices first
+    if (mContext) {
+        mLibUsb->exit(mContext);
    }
-};
+}

 std::vector<std::unique_ptr<IUsbDevice>> UsbDeviceFactory::findAllDevices() {
    refreshDeviceList();
@@ -51,46 +59,51 @@ std::vector<std::unique_ptr<IUsbDevice>> UsbDeviceFactory::findDevices(uint16_t
 ssize_t UsbDeviceFactory::refreshDeviceList() {
    libusb_device** list{nullptr};

-    ssize_t ret = libusb_get_device_list(mLibusbCtx, &list);
-    mLibusbDeviceList.clear();
-    if (ret < 0) {
-        spdlog::error("Error enumarating USB devices");
-    } else if (ret == 0) {
+    ssize_t count = mLibUsb->getDeviceList(mContext, &list);
+    mDeviceList.clear();
+
+    if (count < 0) {
+        spdlog::error("Error enumerating USB devices");
+    } else if (count == 0) {
        spdlog::warn("No USB devices found");
+    } else {
+        for (ssize_t i = 0; i < count; i++) {
+            mLibUsb->refDevice(list[i]);  // Increment refcount
+            // Create LibUsbDevicePtr with deleter that uses the wrapper
+            mDeviceList.emplace_back(list[i], LibUsbDeviceDeleter{mLibUsb});
+        }
    }

-    for (ssize_t i = 0; i < ret; i++) {
-        mLibusbDeviceList.emplace_back(list[i]);
-    }
-
-    libusb_free_device_list(list, false);
-    return ret;
+    mLibUsb->freeDeviceList(list, false);  // Don't unref (we did that above)
+    return count;
 }

 std::vector<std::unique_ptr<IUsbDevice>> UsbDeviceFactory::buildMaskedDeviceVector(uint16_t vidMask, uint16_t pidMask,
                                                                                   uint16_t vid, uint16_t pid) {
    std::vector<std::unique_ptr<IUsbDevice>> matchedDevices;
    // see libusb/examples/listdevs.c
-    for (auto& currDev : mLibusbDeviceList) {
-        struct libusb_device_descriptor currDevDesc{};
+    for (auto& dev : mDeviceList) {
+        libusb_device_descriptor desc{};

-        int ret = libusb_get_device_descriptor(currDev.get(), &currDevDesc);
-        spdlog::trace("Detected Device {:04x}:{:04x} ", currDevDesc.idVendor, currDevDesc.idProduct);
-        if (ret < 0) {
-            continue;
-        }
-        if (((currDevDesc.idVendor & vidMask) == vid) && ((currDevDesc.idProduct & pidMask) == pid)) {
-            matchedDevices.push_back(std::make_unique<UsbDevice>(mLibusbCtx, std::move(currDev)));
+        int ret = mLibUsb->getDeviceDescriptor(dev.get(), &desc);
+        spdlog::trace("Detected Device {:04x}:{:04x} ", desc.idVendor, desc.idProduct);
+
+        if (ret >= 0 && ((desc.idVendor & vidMask) == vid) && ((desc.idProduct & pidMask) == pid)) {
+            // Transfer ownership of device to UsbDevice
+            libusb_device* raw_dev = dev.release();
+
+            // Create UsbDevice with same wrapper instance
+            matchedDevices.push_back(std::make_unique<UsbDevice>(raw_dev, desc, mLibUsb));
        }
    }
    return matchedDevices;
 }

 bool UsbDeviceFactory::init() {
-    auto err = libusb_init(&mLibusbCtx);
+    int err = mLibUsb->init(&mContext);

    if (err != (int)Error::SUCCESS) {
-        spdlog::error("Could not intialize libusb");
+        spdlog::error("Could not initialize libusb");
        return false;
    }

--- a/src/libusbwrap/UsbDeviceFactory.hpp
+++ b/src/libusbwrap/UsbDeviceFactory.hpp
@@ -20,8 +20,10 @@
 #pragma once

 #include <cstdint>
+#include <memory>

 #include "libusb.h"
+#include "libusbwrap/LibUsbWrapper.hpp"
 #include "libusbwrap/UsbDevice.hpp"
 #include "libusbwrap/interface/IUsbDeviceFactory.hpp"

@@ -31,7 +33,12 @@ constexpr const uint16_t LIBUSB_BITMASK_ALL = 0xffff;

 class UsbDeviceFactory : public IUsbDeviceFactory {
   public:
-    UsbDeviceFactory() = default;
+    // Default constructor (uses real LibUsbWrapper)
+    UsbDeviceFactory();
+
+    // Constructor for testing (inject mock wrapper)
+    explicit UsbDeviceFactory(std::shared_ptr<ILibUsbWrapper> libusbWrapper);
+
    virtual ~UsbDeviceFactory();

    // delete copy ctor and assignment
@@ -40,17 +47,17 @@ class UsbDeviceFactory : public IUsbDeviceFactory {
    UsbDeviceFactory(UsbDeviceFactory&&)            = delete;
    UsbDeviceFactory& operator=(UsbDeviceFactory&&) = delete;

-    bool init();
+    bool init() override;
    /**
     * @brief Gets all devices that are detected by libusb. Will allocate a shared_ptr for each Device
-     * 
+     *
     * @return std::vector<std::shared_ptr<IUsbDevice>> Vector of all detected USB devices
     */
    std::vector<std::unique_ptr<IUsbDevice>> findAllDevices() override;
    /**
-     * @brief Gets all devices with certain vid/pid combination. 
+     * @brief Gets all devices with certain vid/pid combination.
     *        If only one device of certain type is connected, vector is usually only one element
-     * 
+     *
     * @param vid VendorId of the devices to find
     * @param pid ProductId of the devices to find
     * @return std::vector<std::shared_ptr<IUsbDevice>> Vector of detected USB devices based on vid/pid
@@ -60,12 +67,12 @@ class UsbDeviceFactory : public IUsbDeviceFactory {
   private:
    // methods
    ssize_t refreshDeviceList();
-    std::vector<std::unique_ptr<IUsbDevice>> buildMaskedDeviceVector(uint16_t vidMask,
-                                                                     uint16_t pidMask, uint16_t vid,
+    std::vector<std::unique_ptr<IUsbDevice>> buildMaskedDeviceVector(uint16_t vidMask, uint16_t pidMask, uint16_t vid,
                                                                     uint16_t pid);
    // members
-    libusb_context* mLibusbCtx{nullptr};
-    std::vector<usbDevice_ptr> mLibusbDeviceList{};
+    std::shared_ptr<ILibUsbWrapper> mLibUsb;
+    libusb_context* mContext{nullptr};  // Factory manages lifecycle
+    std::vector<LibUsbDevicePtr> mDeviceList{};
    bool mDeviceListInitialized = false;
 };
 }  // namespace libusbwrap
--- a/src/libusbwrap/interface/ILibUsbWrapper.hpp
+++ b/src/libusbwrap/interface/ILibUsbWrapper.hpp
--- a/src/libusbwrap/interface/IUsbDeviceFactory.hpp
+++ b/src/libusbwrap/interface/IUsbDeviceFactory.hpp
@@ -29,6 +29,7 @@ namespace libusbwrap {
 class IUsbDeviceFactory {
   public:
    virtual ~IUsbDeviceFactory()                                                             = default;
+    virtual bool init()                                                                      = 0;
    virtual std::vector<std::unique_ptr<IUsbDevice>> findAllDevices()                        = 0;
    virtual std::vector<std::unique_ptr<IUsbDevice>> findDevices(uint16_t vid, uint16_t pid) = 0;
 };
--- a/src/meson.build
+++ b/src/meson.build
@@ -7,6 +7,7 @@ ptprnt_hpps = files(
    'graphics/LabelBuilder.hpp',
    'graphics/Monochrome.hpp',
    'libusbwrap/LibUsbTypes.hpp',
+    'libusbwrap/LibUsbWrapper.hpp',
    'libusbwrap/UsbDevice.hpp',
    'libusbwrap/UsbDeviceFactory.hpp',
    'libusbwrap/interface/IUsbDevice.hpp',
@@ -26,6 +27,7 @@ ptprnt_srcs = files(
    'graphics/Label.cpp',
    'graphics/LabelBuilder.cpp',
    'graphics/Monochrome.cpp',
+    'libusbwrap/LibUsbWrapper.cpp',
    'libusbwrap/UsbDevice.cpp',
    'libusbwrap/UsbDeviceFactory.cpp',
    'printers/FakePrinter.cpp',
--- a/src/printers/FakePrinter.cpp
+++ b/src/printers/FakePrinter.cpp
@@ -113,6 +113,11 @@ bool FakePrinter::printMonochromeData(const graphics::MonochromeData& data) {
 }

 bool FakePrinter::printLabel(const std::unique_ptr<graphics::ILabel> label) {
+    if (!label) {
+        spdlog::error("FakePrinter: Cannot print null label");
+        return false;
+    }
+
    // Convert label directly to MonochromeData
    // getRaw() returns data in Cairo surface coordinates matching getWidth() × getHeight()
    auto pixels = label->getRaw();
--- a/src/printers/P700Printer.cpp
+++ b/src/printers/P700Printer.cpp
@@ -90,6 +90,11 @@ libusbwrap::usbId P700Printer::getUsbId() {
 }

 bool P700Printer::attachUsbDevice(std::shared_ptr<libusbwrap::IUsbDevice> usbHndl) {
+    if (!usbHndl) {
+        spdlog::error("Cannot attach null USB device");
+        return false;
+    }
+
    if (!usbHndl->open()) {
        spdlog::error("Unable to open USB device: {}", usbHndl->getLastErrorString());
        return false;
@@ -133,6 +138,10 @@ bool P700Printer::printBitmap(const graphics::Bitmap<graphics::ALPHA8>& bitmap)
 }

 bool P700Printer::printMonochromeData(const graphics::MonochromeData& data) {
+    if (!mUsbHndl) {
+        spdlog::error("USB Handle is invalid!");
+        return false;
+    }
    // Send initialization sequence
    // The INITIALIZE command needs to be sent as a 128-byte packet with ESC @ at the end
    std::vector<uint8_t> initCmd(128, 0x00);
@@ -182,6 +191,11 @@ bool P700Printer::printMonochromeData(const graphics::MonochromeData& data) {
 }

 bool P700Printer::printLabel(std::unique_ptr<graphics::ILabel> label) {
+    if (!label) {
+        spdlog::error("Cannot print null label");
+        return false;
+    }
+
    // Convert label directly to MonochromeData
    // getRaw() returns data in Cairo surface coordinates matching getWidth() × getHeight()
    auto pixels = label->getRaw();
@@ -200,9 +214,15 @@ bool P700Printer::printLabel(std::unique_ptr<graphics::ILabel> label) {
 }

 bool P700Printer::print() {
-    send(p700::commands::LF);
-    send(p700::commands::FF);
-    send(p700::commands::EJECT);
+    if (!send(p700::commands::LF)) {
+        return false;
+    }
+    if (!send(p700::commands::FF)) {
+        return false;
+    }
+    if (!send(p700::commands::EJECT)) {
+        return false;
+    }
    return true;
 }

--- a/tests/cli_parser_test/cli_parser_test.cpp
+++ b/tests/cli_parser_test/cli_parser_test.cpp
@@ -0,0 +1,365 @@
+/*
+    ptrnt - print labels on linux
+    Copyright (C) 2025  Moritz Martinius
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+ */
+
+#include <gtest/gtest.h>
+
+#include <cstring>
+#include <vector>
+
+#include "cli/CliParser.hpp"
+
+namespace ptprnt::cli {
+
+class CliParserTest : public ::testing::Test {
+   protected:
+    void SetUp() override {
+        parser = std::make_unique<CliParser>("Test Application", "v1.0.0");
+    }
+
+    void TearDown() override { parser.reset(); }
+
+    // Helper to convert vector of strings to argc/argv
+    std::vector<char*> makeArgv(const std::vector<std::string>& args) {
+        argv_storage.clear();
+        argv_storage.reserve(args.size());
+
+        for (const auto& arg : args) {
+            argv_storage.push_back(const_cast<char*>(arg.c_str()));
+        }
+
+        return argv_storage;
+    }
+
+    std::unique_ptr<CliParser> parser;
+    std::vector<char*> argv_storage;
+};
+
+// Test: Constructor
+TEST_F(CliParserTest, Constructor) {
+    EXPECT_NO_THROW(CliParser("App", "v1.0"));
+}
+
+// Test: Parse with no arguments
+TEST_F(CliParserTest, ParseNoArguments) {
+    std::vector<std::string> args = {"ptprnt"};
+    auto argv = makeArgv(args);
+
+    int result = parser->parse(args.size(), argv.data());
+
+    EXPECT_EQ(result, 0);
+    const auto& options = parser->getOptions();
+    EXPECT_FALSE(options.verbose);
+    EXPECT_FALSE(options.trace);
+    EXPECT_FALSE(options.listDrivers);
+    EXPECT_EQ(options.printerSelection, "auto");
+    EXPECT_TRUE(options.commands.empty());
+}
+
+// Test: Parse verbose flag
+TEST_F(CliParserTest, ParseVerboseShort) {
+    std::vector<std::string> args = {"ptprnt", "-v"};
+    auto argv = makeArgv(args);
+
+    int result = parser->parse(args.size(), argv.data());
+
+    EXPECT_EQ(result, 0);
+    EXPECT_TRUE(parser->getOptions().verbose);
+}
+
+TEST_F(CliParserTest, ParseVerboseLong) {
+    std::vector<std::string> args = {"ptprnt", "--verbose"};
+    auto argv = makeArgv(args);
+
+    int result = parser->parse(args.size(), argv.data());
+
+    EXPECT_EQ(result, 0);
+    EXPECT_TRUE(parser->getOptions().verbose);
+}
+
+// Test: Parse trace flag
+TEST_F(CliParserTest, ParseTrace) {
+    std::vector<std::string> args = {"ptprnt", "--trace"};
+    auto argv = makeArgv(args);
+
+    int result = parser->parse(args.size(), argv.data());
+
+    EXPECT_EQ(result, 0);
+    EXPECT_TRUE(parser->getOptions().trace);
+}
+
+// Test: Parse list drivers flag
+TEST_F(CliParserTest, ParseListDrivers) {
+    std::vector<std::string> args = {"ptprnt", "--list-all-drivers"};
+    auto argv = makeArgv(args);
+
+    int result = parser->parse(args.size(), argv.data());
+
+    EXPECT_EQ(result, 0);
+    EXPECT_TRUE(parser->getOptions().listDrivers);
+}
+
+// Test: Parse printer selection short
+TEST_F(CliParserTest, ParsePrinterShort) {
+    std::vector<std::string> args = {"ptprnt", "-p", "P700"};
+    auto argv = makeArgv(args);
+
+    int result = parser->parse(args.size(), argv.data());
+
+    EXPECT_EQ(result, 0);
+    EXPECT_EQ(parser->getOptions().printerSelection, "P700");
+}
+
+// Test: Parse printer selection long
+TEST_F(CliParserTest, ParsePrinterLong) {
+    std::vector<std::string> args = {"ptprnt", "--printer", "FakePrinter"};
+    auto argv = makeArgv(args);
+
+    int result = parser->parse(args.size(), argv.data());
+
+    EXPECT_EQ(result, 0);
+    EXPECT_EQ(parser->getOptions().printerSelection, "FakePrinter");
+}
+
+// Test: Parse single text
+TEST_F(CliParserTest, ParseSingleText) {
+    std::vector<std::string> args = {"ptprnt", "-t", "Hello"};
+    auto argv = makeArgv(args);
+
+    int result = parser->parse(args.size(), argv.data());
+
+    EXPECT_EQ(result, 0);
+    const auto& commands = parser->getOptions().commands;
+    ASSERT_EQ(commands.size(), 1);
+    EXPECT_EQ(commands[0].first, CommandType::Text);
+    EXPECT_EQ(commands[0].second, "Hello");
+}
+
+// Test: Parse multiple texts
+TEST_F(CliParserTest, ParseMultipleTexts) {
+    std::vector<std::string> args = {"ptprnt", "-t", "Hello", "-t", "World"};
+    auto argv = makeArgv(args);
+
+    int result = parser->parse(args.size(), argv.data());
+
+    EXPECT_EQ(result, 0);
+    const auto& commands = parser->getOptions().commands;
+    ASSERT_EQ(commands.size(), 2);
+    EXPECT_EQ(commands[0].first, CommandType::Text);
+    EXPECT_EQ(commands[0].second, "Hello");
+    EXPECT_EQ(commands[1].first, CommandType::Text);
+    EXPECT_EQ(commands[1].second, "World");
+}
+
+// Test: Parse font
+TEST_F(CliParserTest, ParseFont) {
+    std::vector<std::string> args = {"ptprnt", "-f", "monospace", "-t", "Test"};
+    auto argv = makeArgv(args);
+
+    int result = parser->parse(args.size(), argv.data());
+
+    EXPECT_EQ(result, 0);
+    const auto& commands = parser->getOptions().commands;
+    ASSERT_EQ(commands.size(), 2);
+    EXPECT_EQ(commands[0].first, CommandType::Font);
+    EXPECT_EQ(commands[0].second, "monospace");
+}
+
+// Test: Parse font size
+TEST_F(CliParserTest, ParseFontSize) {
+    std::vector<std::string> args = {"ptprnt", "-s", "48", "-t", "Large"};
+    auto argv = makeArgv(args);
+
+    int result = parser->parse(args.size(), argv.data());
+
+    EXPECT_EQ(result, 0);
+    const auto& commands = parser->getOptions().commands;
+    ASSERT_GE(commands.size(), 1);
+    EXPECT_EQ(commands[0].first, CommandType::FontSize);
+    EXPECT_EQ(commands[0].second, "48");
+}
+
+// Test: Parse horizontal alignment
+TEST_F(CliParserTest, ParseHAlign) {
+    std::vector<std::string> args = {"ptprnt", "--halign", "center", "-t", "Centered"};
+    auto argv = makeArgv(args);
+
+    int result = parser->parse(args.size(), argv.data());
+
+    EXPECT_EQ(result, 0);
+    const auto& commands = parser->getOptions().commands;
+    ASSERT_GE(commands.size(), 1);
+    EXPECT_EQ(commands[0].first, CommandType::HAlign);
+    EXPECT_EQ(commands[0].second, "center");
+}
+
+// Test: Parse vertical alignment
+TEST_F(CliParserTest, ParseVAlign) {
+    std::vector<std::string> args = {"ptprnt", "--valign", "top", "-t", "Top"};
+    auto argv = makeArgv(args);
+
+    int result = parser->parse(args.size(), argv.data());
+
+    EXPECT_EQ(result, 0);
+    const auto& commands = parser->getOptions().commands;
+    ASSERT_GE(commands.size(), 1);
+    EXPECT_EQ(commands[0].first, CommandType::VAlign);
+    EXPECT_EQ(commands[0].second, "top");
+}
+
+// Test: Parse new label flag
+TEST_F(CliParserTest, ParseNewLabel) {
+    std::vector<std::string> args = {"ptprnt", "-t", "First", "--new", "-t", "Second"};
+    auto argv = makeArgv(args);
+
+    int result = parser->parse(args.size(), argv.data());
+
+    EXPECT_EQ(result, 0);
+    const auto& commands = parser->getOptions().commands;
+    ASSERT_EQ(commands.size(), 3);
+    EXPECT_EQ(commands[0].first, CommandType::Text);
+    EXPECT_EQ(commands[1].first, CommandType::NewLabel);
+    EXPECT_EQ(commands[2].first, CommandType::Text);
+}
+
+// Test: Parse complex command sequence
+TEST_F(CliParserTest, ParseComplexSequence) {
+    std::vector<std::string> args = {
+        "ptprnt",
+        "-f", "serif",
+        "-s", "24",
+        "--halign", "center",
+        "--valign", "middle",
+        "-t", "Title",
+        "--new",
+        "-f", "monospace",
+        "-s", "16",
+        "-t", "Body"
+    };
+    auto argv = makeArgv(args);
+
+    int result = parser->parse(args.size(), argv.data());
+
+    EXPECT_EQ(result, 0);
+    const auto& commands = parser->getOptions().commands;
+    ASSERT_EQ(commands.size(), 9);
+
+    // Verify order is preserved
+    EXPECT_EQ(commands[0].first, CommandType::Font);
+    EXPECT_EQ(commands[1].first, CommandType::FontSize);
+    EXPECT_EQ(commands[2].first, CommandType::HAlign);
+    EXPECT_EQ(commands[3].first, CommandType::VAlign);
+    EXPECT_EQ(commands[4].first, CommandType::Text);
+    EXPECT_EQ(commands[5].first, CommandType::NewLabel);
+    EXPECT_EQ(commands[6].first, CommandType::Font);
+    EXPECT_EQ(commands[7].first, CommandType::FontSize);
+    EXPECT_EQ(commands[8].first, CommandType::Text);
+}
+
+// Test: Parse with verbose and printer options
+TEST_F(CliParserTest, ParseCombinedOptions) {
+    std::vector<std::string> args = {
+        "ptprnt",
+        "-v",
+        "--trace",
+        "-p", "P700",
+        "-t", "Test"
+    };
+    auto argv = makeArgv(args);
+
+    int result = parser->parse(args.size(), argv.data());
+
+    EXPECT_EQ(result, 0);
+    EXPECT_TRUE(parser->getOptions().verbose);
+    EXPECT_TRUE(parser->getOptions().trace);
+    EXPECT_EQ(parser->getOptions().printerSelection, "P700");
+    EXPECT_FALSE(parser->getOptions().commands.empty());
+}
+
+// Test: Parse help flag (should return 1)
+TEST_F(CliParserTest, ParseHelp) {
+    std::vector<std::string> args = {"ptprnt", "-h"};
+    auto argv = makeArgv(args);
+
+    int result = parser->parse(args.size(), argv.data());
+
+    EXPECT_EQ(result, 1);  // Signal clean exit
+}
+
+TEST_F(CliParserTest, ParseHelpLong) {
+    std::vector<std::string> args = {"ptprnt", "--help"};
+    auto argv = makeArgv(args);
+
+    int result = parser->parse(args.size(), argv.data());
+
+    EXPECT_EQ(result, 1);  // Signal clean exit
+}
+
+// Test: Parse version flag (should return 1)
+TEST_F(CliParserTest, ParseVersion) {
+    std::vector<std::string> args = {"ptprnt", "-V"};
+    auto argv = makeArgv(args);
+
+    int result = parser->parse(args.size(), argv.data());
+
+    EXPECT_EQ(result, 1);  // Signal clean exit
+}
+
+TEST_F(CliParserTest, ParseVersionLong) {
+    std::vector<std::string> args = {"ptprnt", "--version"};
+    auto argv = makeArgv(args);
+
+    int result = parser->parse(args.size(), argv.data());
+
+    EXPECT_EQ(result, 1);  // Signal clean exit
+}
+
+// Test: Parse invalid option (should return -1)
+TEST_F(CliParserTest, ParseInvalidOption) {
+    std::vector<std::string> args = {"ptprnt", "--invalid-option"};
+    auto argv = makeArgv(args);
+
+    int result = parser->parse(args.size(), argv.data());
+
+    EXPECT_EQ(result, -1);  // Signal error
+}
+
+// Test: Default printer selection is "auto"
+TEST_F(CliParserTest, DefaultPrinterSelection) {
+    std::vector<std::string> args = {"ptprnt", "-t", "Test"};
+    auto argv = makeArgv(args);
+
+    parser->parse(args.size(), argv.data());
+
+    EXPECT_EQ(parser->getOptions().printerSelection, "auto");
+}
+
+// Test: Long text with spaces
+TEST_F(CliParserTest, ParseTextWithSpaces) {
+    std::vector<std::string> args = {"ptprnt", "-t", "Hello World"};
+    auto argv = makeArgv(args);
+
+    int result = parser->parse(args.size(), argv.data());
+
+    EXPECT_EQ(result, 0);
+    const auto& commands = parser->getOptions().commands;
+    ASSERT_EQ(commands.size(), 1);
+    EXPECT_EQ(commands[0].second, "Hello World");
+}
+
+}  // namespace ptprnt::cli
--- a/tests/fake_printer_test/fake_printer_test.cpp
+++ b/tests/fake_printer_test/fake_printer_test.cpp
@@ -0,0 +1,247 @@
+/*
+    ptrnt - print labels on linux
+    Copyright (C) 2025  Moritz Martinius
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+ */
+
+#include <gtest/gtest.h>
+
+#include "graphics/Bitmap.hpp"
+#include "graphics/Label.hpp"
+#include "graphics/Monochrome.hpp"
+#include "printers/FakePrinter.hpp"
+
+namespace ptprnt::printer {
+
+class FakePrinterTest : public ::testing::Test {
+   protected:
+    void SetUp() override {
+        printer = std::make_unique<FakePrinter>();
+    }
+
+    void TearDown() override { printer.reset(); }
+
+    std::unique_ptr<FakePrinter> printer;
+};
+
+// Test: Get driver name
+TEST_F(FakePrinterTest, GetDriverName) {
+    auto name = printer->getDriverName();
+    EXPECT_FALSE(name.empty());
+    EXPECT_EQ(name, "FakePrinter");
+}
+
+// Test: Get printer name
+TEST_F(FakePrinterTest, GetName) {
+    auto name = printer->getName();
+    EXPECT_FALSE(name.empty());
+}
+
+// Test: Get USB ID
+TEST_F(FakePrinterTest, GetUsbId) {
+    auto usbId = printer->getUsbId();
+    EXPECT_EQ(usbId.first, 0x0000);   // Virtual printer - no USB ID
+    EXPECT_EQ(usbId.second, 0x0000);  // Virtual printer - no USB ID
+}
+
+// Test: Get printer version
+TEST_F(FakePrinterTest, GetVersion) {
+    auto version = printer->getVersion();
+    EXPECT_FALSE(version.empty());
+}
+
+// Test: Get printer info
+TEST_F(FakePrinterTest, GetPrinterInfo) {
+    auto info = printer->getPrinterInfo();
+
+    EXPECT_FALSE(info.driverName.empty());
+    EXPECT_FALSE(info.name.empty());
+    EXPECT_GT(info.pixelLines, 0);
+}
+
+// Test: Get printer status without device
+TEST_F(FakePrinterTest, GetPrinterStatusWithoutDevice) {
+    auto status = printer->getPrinterStatus();
+
+    // FakePrinter should return empty status when no device attached
+    EXPECT_EQ(status.tapeWidthMm, 0);
+}
+
+// Test: Get printer status with device
+TEST_F(FakePrinterTest, GetPrinterStatusWithDevice) {
+    printer->attachUsbDevice(nullptr);
+    auto status = printer->getPrinterStatus();
+
+    // FakePrinter should return default status when device attached
+    EXPECT_EQ(status.tapeWidthMm, 12);  // Default tape width
+}
+
+// Test: Attach USB device (should always succeed for fake printer)
+TEST_F(FakePrinterTest, AttachUsbDevice) {
+    bool result = printer->attachUsbDevice(nullptr);
+
+    // FakePrinter doesn't need a real device
+    EXPECT_TRUE(result);
+}
+
+// Test: Detach USB device
+TEST_F(FakePrinterTest, DetachUsbDevice) {
+    printer->attachUsbDevice(nullptr);
+    bool result = printer->detachUsbDevice();
+
+    EXPECT_TRUE(result);
+}
+
+// Test: Print without attaching device first
+TEST_F(FakePrinterTest, PrintWithoutDevice) {
+    bool result = printer->print();
+
+    // FakePrinter should fail if no device attached
+    EXPECT_FALSE(result);
+}
+
+// Test: Print after attaching device
+TEST_F(FakePrinterTest, PrintWithDevice) {
+    printer->attachUsbDevice(nullptr);
+    bool result = printer->print();
+
+    EXPECT_TRUE(result);
+}
+
+// Test: Print bitmap
+TEST_F(FakePrinterTest, PrintBitmap) {
+    graphics::Bitmap<graphics::ALPHA8> bitmap(100, 128);
+
+    // Fill with some pattern
+    std::vector<graphics::ALPHA8> pixels(bitmap.getWidth() * bitmap.getHeight());
+    for (size_t i = 0; i < pixels.size(); ++i) {
+        pixels[i] = (i % 2) ? 0xFF : 0x00;
+    }
+    bitmap.setPixels(pixels);
+
+    printer->attachUsbDevice(nullptr);
+    bool result = printer->printBitmap(bitmap);
+
+    EXPECT_TRUE(result);
+
+    // Check that last print was saved
+    const auto& lastPrint = printer->getLastPrint();
+    EXPECT_GT(lastPrint.getWidth(), 0);
+    EXPECT_GT(lastPrint.getHeight(), 0);
+}
+
+// Test: Print monochrome data
+TEST_F(FakePrinterTest, PrintMonochromeData) {
+    graphics::Bitmap<graphics::ALPHA8> bitmap(50, 128);
+    auto pixels = bitmap.getPixelsCpy();
+    auto mono   = graphics::Monochrome(pixels, bitmap.getWidth(), bitmap.getHeight());
+    auto data   = mono.get();
+
+    printer->attachUsbDevice(nullptr);
+    bool result = printer->printMonochromeData(data);
+
+    EXPECT_TRUE(result);
+
+    // Verify last print
+    const auto& lastPrint = printer->getLastPrint();
+    EXPECT_GT(lastPrint.getWidth(), 0);
+}
+
+// Test: Print label
+TEST_F(FakePrinterTest, PrintLabel) {
+    auto label = std::make_unique<graphics::Label>(128);
+    label->create("Test Label");
+
+    printer->attachUsbDevice(nullptr);
+    bool result = printer->printLabel(std::move(label));
+
+    EXPECT_TRUE(result);
+}
+
+// Test: Print null label
+TEST_F(FakePrinterTest, PrintNullLabel) {
+    printer->attachUsbDevice(nullptr);
+    bool result = printer->printLabel(nullptr);
+
+    EXPECT_FALSE(result);
+}
+
+// Test: Print empty bitmap
+TEST_F(FakePrinterTest, PrintEmptyBitmap) {
+    graphics::Bitmap<graphics::ALPHA8> bitmap(0, 0);
+
+    printer->attachUsbDevice(nullptr);
+    bool result = printer->printBitmap(bitmap);
+
+    // Should handle empty bitmap gracefully
+    EXPECT_TRUE(result);
+}
+
+// Test: Get last print before printing
+TEST_F(FakePrinterTest, GetLastPrintBeforePrinting) {
+    // Should throw when getting last print before any print operation
+    EXPECT_THROW({
+        const auto& lastPrint = printer->getLastPrint();
+        (void)lastPrint;  // Suppress unused variable warning
+    }, std::runtime_error);
+}
+
+// Test: Save last print to PNG (may fail without valid data)
+TEST_F(FakePrinterTest, SaveLastPrintToPng) {
+    graphics::Bitmap<graphics::ALPHA8> bitmap(100, 128);
+
+    printer->attachUsbDevice(nullptr);
+    printer->printBitmap(bitmap);
+
+    // Try to save to /tmp
+    bool result = printer->saveLastPrintToPng("/tmp/test_fake_printer_output.png");
+
+    // Should succeed if we have valid print data
+    EXPECT_TRUE(result);
+}
+
+// Test: Multiple prints
+TEST_F(FakePrinterTest, MultiplePrints) {
+    graphics::Bitmap<graphics::ALPHA8> bitmap1(50, 128);
+    graphics::Bitmap<graphics::ALPHA8> bitmap2(100, 128);
+
+    printer->attachUsbDevice(nullptr);
+
+    bool result1 = printer->printBitmap(bitmap1);
+    EXPECT_TRUE(result1);
+
+    bool result2 = printer->printBitmap(bitmap2);
+    EXPECT_TRUE(result2);
+
+    // Last print should be from second bitmap
+    const auto& lastPrint = printer->getLastPrint();
+    EXPECT_GT(lastPrint.getWidth(), 0);
+}
+
+// Test: Detach and reattach
+TEST_F(FakePrinterTest, DetachAndReattach) {
+    printer->attachUsbDevice(nullptr);
+    EXPECT_TRUE(printer->detachUsbDevice());
+
+    // Should be able to reattach
+    EXPECT_TRUE(printer->attachUsbDevice(nullptr));
+
+    // Should be able to print after reattach
+    graphics::Bitmap<graphics::ALPHA8> bitmap(50, 128);
+    EXPECT_TRUE(printer->printBitmap(bitmap));
+}
+
+}  // namespace ptprnt::printer
--- a/tests/label_builder_test/label_builder_test.cpp
+++ b/tests/label_builder_test/label_builder_test.cpp
@@ -0,0 +1,230 @@
+/*
+    ptrnt - print labels on linux
+    Copyright (C) 2025  Moritz Martinius
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+ */
+
+#include <gtest/gtest.h>
+
+#include "graphics/LabelBuilder.hpp"
+#include "graphics/interface/ILabel.hpp"
+
+namespace ptprnt::graphics {
+
+class LabelBuilderTest : public ::testing::Test {
+   protected:
+    void SetUp() override {
+        builder = std::make_unique<LabelBuilder>(128);  // P700 printer height
+    }
+
+    void TearDown() override { builder.reset(); }
+
+    std::unique_ptr<LabelBuilder> builder;
+};
+
+// Test: Constructor
+TEST_F(LabelBuilderTest, Constructor) {
+    EXPECT_NO_THROW(LabelBuilder(128));
+    EXPECT_NO_THROW(LabelBuilder(64));
+}
+
+// Test: Add single text
+TEST_F(LabelBuilderTest, AddSingleText) {
+    auto& result = builder->addText("Hello");
+
+    // Should return reference to builder for chaining
+    EXPECT_EQ(&result, builder.get());
+}
+
+// Test: Add multiple texts
+TEST_F(LabelBuilderTest, AddMultipleTexts) {
+    builder->addText("Line 1")
+           .addText("Line 2")
+           .addText("Line 3");
+
+    // Build should succeed
+    auto label = builder->build();
+    EXPECT_NE(label, nullptr);
+}
+
+// Test: Add empty text (should be ignored)
+TEST_F(LabelBuilderTest, AddEmptyText) {
+    builder->addText("");
+
+    auto label = builder->build();
+    EXPECT_NE(label, nullptr);
+}
+
+// Test: Set font family
+TEST_F(LabelBuilderTest, SetFontFamily) {
+    auto& result = builder->setFontFamily("monospace");
+
+    // Should return reference to builder for chaining
+    EXPECT_EQ(&result, builder.get());
+}
+
+// Test: Set font size
+TEST_F(LabelBuilderTest, SetFontSize) {
+    auto& result = builder->setFontSize(24.0);
+
+    // Should return reference to builder for chaining
+    EXPECT_EQ(&result, builder.get());
+}
+
+// Test: Set horizontal alignment
+TEST_F(LabelBuilderTest, SetHAlign) {
+    auto& result = builder->setHAlign(HAlignPosition::CENTER);
+
+    // Should return reference to builder for chaining
+    EXPECT_EQ(&result, builder.get());
+}
+
+// Test: Set vertical alignment
+TEST_F(LabelBuilderTest, SetVAlign) {
+    auto& result = builder->setVAlign(VAlignPosition::TOP);
+
+    // Should return reference to builder for chaining
+    EXPECT_EQ(&result, builder.get());
+}
+
+// Test: Build with default settings
+TEST_F(LabelBuilderTest, BuildWithDefaults) {
+    builder->addText("Test");
+
+    auto label = builder->build();
+
+    EXPECT_NE(label, nullptr);
+    EXPECT_GT(label->getWidth(), 0);
+    EXPECT_GT(label->getHeight(), 0);
+}
+
+// Test: Build with custom settings
+TEST_F(LabelBuilderTest, BuildWithCustomSettings) {
+    builder->setFontFamily("serif")
+           .setFontSize(48.0)
+           .setHAlign(HAlignPosition::CENTER)
+           .setVAlign(VAlignPosition::MIDDLE)
+           .addText("Custom Text");
+
+    auto label = builder->build();
+
+    EXPECT_NE(label, nullptr);
+}
+
+// Test: Method chaining
+TEST_F(LabelBuilderTest, MethodChaining) {
+    auto label = builder->setFontFamily("monospace")
+                         .setFontSize(20.0)
+                         .setHAlign(HAlignPosition::RIGHT)
+                         .setVAlign(VAlignPosition::BOTTOM)
+                         .addText("Chained")
+                         .addText("Methods")
+                         .build();
+
+    EXPECT_NE(label, nullptr);
+}
+
+// Test: Reset builder
+TEST_F(LabelBuilderTest, Reset) {
+    builder->setFontFamily("monospace")
+           .setFontSize(48.0)
+           .setHAlign(HAlignPosition::RIGHT)
+           .setVAlign(VAlignPosition::BOTTOM)
+           .addText("Test");
+
+    auto& result = builder->reset();
+
+    // Should return reference to builder for chaining
+    EXPECT_EQ(&result, builder.get());
+
+    // After reset, should be able to build with defaults
+    builder->addText("After Reset");
+    auto label = builder->build();
+    EXPECT_NE(label, nullptr);
+}
+
+// Test: Build empty label
+TEST_F(LabelBuilderTest, BuildEmptyLabel) {
+    // Build without adding any text
+    auto label = builder->build();
+
+    EXPECT_NE(label, nullptr);
+}
+
+// Test: Multiple builds from same builder
+TEST_F(LabelBuilderTest, MultipleBuilds) {
+    builder->addText("First Build");
+    auto label1 = builder->build();
+    EXPECT_NE(label1, nullptr);
+
+    // Build again with same content
+    auto label2 = builder->build();
+    EXPECT_NE(label2, nullptr);
+
+    // Both labels should be valid
+    EXPECT_GT(label1->getWidth(), 0);
+    EXPECT_GT(label2->getWidth(), 0);
+}
+
+// Test: All horizontal alignments
+TEST_F(LabelBuilderTest, AllHorizontalAlignments) {
+    builder->addText("Left").setHAlign(HAlignPosition::LEFT);
+    auto label1 = builder->build();
+    EXPECT_NE(label1, nullptr);
+
+    builder->reset().addText("Center").setHAlign(HAlignPosition::CENTER);
+    auto label2 = builder->build();
+    EXPECT_NE(label2, nullptr);
+
+    builder->reset().addText("Right").setHAlign(HAlignPosition::RIGHT);
+    auto label3 = builder->build();
+    EXPECT_NE(label3, nullptr);
+
+    builder->reset().addText("Justify").setHAlign(HAlignPosition::JUSTIFY);
+    auto label4 = builder->build();
+    EXPECT_NE(label4, nullptr);
+}
+
+// Test: All vertical alignments
+TEST_F(LabelBuilderTest, AllVerticalAlignments) {
+    builder->addText("Top").setVAlign(VAlignPosition::TOP);
+    auto label1 = builder->build();
+    EXPECT_NE(label1, nullptr);
+
+    builder->reset().addText("Middle").setVAlign(VAlignPosition::MIDDLE);
+    auto label2 = builder->build();
+    EXPECT_NE(label2, nullptr);
+
+    builder->reset().addText("Bottom").setVAlign(VAlignPosition::BOTTOM);
+    auto label3 = builder->build();
+    EXPECT_NE(label3, nullptr);
+}
+
+// Test: Different font sizes
+TEST_F(LabelBuilderTest, DifferentFontSizes) {
+    builder->setFontSize(12.0).addText("Small");
+    auto label1 = builder->build();
+    EXPECT_NE(label1, nullptr);
+
+    builder->reset().setFontSize(64.0).addText("Large");
+    auto label2 = builder->build();
+    EXPECT_NE(label2, nullptr);
+
+    // Larger font should produce wider label (assuming same text length)
+    // Note: This is a heuristic test and may not always be true depending on font rendering
+}
+
+}  // namespace ptprnt::graphics
--- a/tests/label_test/label_test.cpp
+++ b/tests/label_test/label_test.cpp
@@ -25,8 +25,8 @@
 #include <memory>
 #include <vector>

-#include "../../tests/mocks/MockCairoWrapper.hpp"
 #include "graphics/interface/ILabel.hpp"
+#include "mocks/MockCairoWrapper.hpp"

 using ::testing::_;
 using ::testing::DoAll;
--- a/tests/meson.build
+++ b/tests/meson.build
@@ -5,11 +5,38 @@ test_sources = [
    'bitmap_test/bitmap_test.cpp',
    'monochrome_test/monochrome_test.cpp',
    'label_test/label_test.cpp',
+    'label_builder_test/label_builder_test.cpp',
+    'printer_service_test/printer_service_test.cpp',
+    'p700_printer_test/p700_printer_test.cpp',
+    'fake_printer_test/fake_printer_test.cpp',
+    'cli_parser_test/cli_parser_test.cpp',
+    'ptouch_print_test/ptouch_print_test.cpp',
+    'usb_device_test/usb_device_test.cpp',

-    # Source files under test
+    # Source files under test - graphics
    '../src/graphics/Bitmap.cpp',
    '../src/graphics/Monochrome.cpp',
    '../src/graphics/Label.cpp',
+    '../src/graphics/LabelBuilder.cpp',
+
+    # Source files under test - core
+    '../src/core/PrinterService.cpp',
+    '../src/core/PrinterDriverFactory.cpp',
+
+    # Source files under test - printers
+    '../src/printers/P700Printer.cpp',
+    '../src/printers/FakePrinter.cpp',
+
+    # Source files under test - CLI
+    '../src/cli/CliParser.cpp',
+
+    # Source files under test - Main app
+    '../src/PtouchPrint.cpp',
+
+    # Source files under test - USB
+    '../src/libusbwrap/LibUsbWrapper.cpp',
+    '../src/libusbwrap/UsbDevice.cpp',
+    '../src/libusbwrap/UsbDeviceFactory.cpp',
 ]

 test_exe = executable(
@@ -17,7 +44,7 @@ test_exe = executable(
    sources: test_sources,
    include_directories: incdir,
    dependencies: [
-        gmock_dep,  # GMock includes GTest
+        gmock_dep, # GMock includes GTest
        usb_dep,
        log_dep,
        pangocairo_dep,
@@ -26,4 +53,4 @@ test_exe = executable(
 )

 # Single test that runs all test suites
-test('all_tests', test_exe)
+test('all_tests', test_exe)
--- a/tests/mocks/MockLibUsbWrapper.hpp
+++ b/tests/mocks/MockLibUsbWrapper.hpp
@@ -0,0 +1,76 @@
+/*
+    ptrnt - print labels on linux
+    Copyright (C) 2025  Moritz Martinius
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+ */
+
+#pragma once
+
+#include <gmock/gmock.h>
+
+#include "libusbwrap/LibUsbWrapper.hpp"
+
+namespace libusbwrap {
+
+/**
+ * @brief GMock implementation of ILibUsbWrapper for unit testing
+ *
+ * This mock allows tests to verify that UsbDevice and UsbDeviceFactory
+ * correctly interact with the libusb API without requiring actual USB hardware.
+ */
+class MockLibUsbWrapper : public ILibUsbWrapper {
+   public:
+    // Context management
+    MOCK_METHOD(int, init, (libusb_context * *ctx), (override));
+    MOCK_METHOD(void, exit, (libusb_context * ctx), (override));
+
+    // Device enumeration
+    MOCK_METHOD(ssize_t, getDeviceList, (libusb_context * ctx, libusb_device*** list), (override));
+    MOCK_METHOD(void, freeDeviceList, (libusb_device * *list, int unrefDevices), (override));
+    MOCK_METHOD(void, refDevice, (libusb_device * dev), (override));
+    MOCK_METHOD(void, unrefDevice, (libusb_device * dev), (override));
+
+    // Device descriptor
+    MOCK_METHOD(int, getDeviceDescriptor, (libusb_device * dev, libusb_device_descriptor* desc), (override));
+
+    // Device opening/closing
+    MOCK_METHOD(int, open, (libusb_device * dev, libusb_device_handle** handle), (override));
+    MOCK_METHOD(void, close, (libusb_device_handle * handle), (override));
+
+    // Device information
+    MOCK_METHOD(int, getSpeed, (libusb_device * dev), (override));
+    MOCK_METHOD(uint8_t, getBusNumber, (libusb_device * dev), (override));
+    MOCK_METHOD(uint8_t, getPortNumber, (libusb_device * dev), (override));
+
+    // Kernel driver management
+    MOCK_METHOD(int, kernelDriverActive, (libusb_device_handle * handle, int interfaceNo), (override));
+    MOCK_METHOD(int, detachKernelDriver, (libusb_device_handle * handle, int interfaceNo), (override));
+
+    // Interface management
+    MOCK_METHOD(int, claimInterface, (libusb_device_handle * handle, int interfaceNo), (override));
+    MOCK_METHOD(int, releaseInterface, (libusb_device_handle * handle, int interfaceNo), (override));
+
+    // Data transfer
+    MOCK_METHOD(int, bulkTransfer,
+                (libusb_device_handle * handle, uint8_t endpoint, unsigned char* data, int length, int* transferred,
+                 unsigned int timeout),
+                (override));
+
+    // Error handling
+    MOCK_METHOD(const char*, errorName, (int errorCode), (override));
+};
+
+}  // namespace libusbwrap
--- a/tests/mocks/MockPrinterDriver.hpp
+++ b/tests/mocks/MockPrinterDriver.hpp
@@ -0,0 +1,50 @@
+/*
+    ptrnt - print labels on linux
+    Copyright (C) 2025  Moritz Martinius
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+ */
+
+#pragma once
+
+#include <gmock/gmock.h>
+
+#include "printers/interface/IPrinterDriver.hpp"
+
+namespace ptprnt {
+
+/**
+ * @brief GMock implementation of IPrinterDriver for unit testing
+ *
+ * This mock allows tests to verify printer interactions without
+ * requiring actual printer hardware.
+ */
+class MockPrinterDriver : public IPrinterDriver {
+   public:
+    MOCK_METHOD(std::string_view, getDriverName, (), (override));
+    MOCK_METHOD(std::string_view, getName, (), (override));
+    MOCK_METHOD(std::string_view, getVersion, (), (override));
+    MOCK_METHOD(libusbwrap::usbId, getUsbId, (), (override));
+    MOCK_METHOD(PrinterInfo, getPrinterInfo, (), (override));
+    MOCK_METHOD(PrinterStatus, getPrinterStatus, (), (override));
+    MOCK_METHOD(bool, attachUsbDevice, (std::shared_ptr<libusbwrap::IUsbDevice> usbHndl), (override));
+    MOCK_METHOD(bool, detachUsbDevice, (), (override));
+    MOCK_METHOD(bool, printBitmap, (const graphics::Bitmap<graphics::ALPHA8>& bitmap), (override));
+    MOCK_METHOD(bool, printMonochromeData, (const graphics::MonochromeData& data), (override));
+    MOCK_METHOD(bool, printLabel, (const std::unique_ptr<graphics::ILabel> label), (override));
+    MOCK_METHOD(bool, print, (), (override));
+};
+
+}  // namespace ptprnt
--- a/tests/mocks/MockUsbDevice.hpp
+++ b/tests/mocks/MockUsbDevice.hpp
@@ -0,0 +1,57 @@
+/*
+    ptrnt - print labels on linux
+    Copyright (C) 2025  Moritz Martinius
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+ */
+
+#pragma once
+
+#include <gmock/gmock.h>
+
+#include "libusbwrap/interface/IUsbDevice.hpp"
+
+namespace libusbwrap {
+
+/**
+ * @brief GMock implementation of IUsbDevice for unit testing
+ *
+ * This mock allows tests to verify USB device interactions without
+ * requiring actual hardware or libusb context.
+ */
+class MockUsbDevice : public IUsbDevice {
+   public:
+    MOCK_METHOD(bool, open, (), (override));
+    MOCK_METHOD(void, close, (), (override));
+
+    // libusb wrappers
+    MOCK_METHOD(bool, detachKernelDriver, (int interfaceNo), (override));
+    MOCK_METHOD(bool, claimInterface, (int interfaceNo), (override));
+    MOCK_METHOD(bool, releaseInterface, (int interfaceNo), (override));
+    MOCK_METHOD(bool, bulkTransfer,
+                (uint8_t endpoint, const std::vector<uint8_t>& data, int* tx, unsigned int timeout), (override));
+
+    // getters
+    MOCK_METHOD(const usbId, getUsbId, (), (override));
+    MOCK_METHOD(const device::Speed, getSpeed, (), (override));
+    MOCK_METHOD(const uint8_t, getBusNumber, (), (override));
+    MOCK_METHOD(const uint8_t, getPortNumber, (), (override));
+
+    // errors
+    MOCK_METHOD(const Error, getLastError, (), (override));
+    MOCK_METHOD(const std::string, getLastErrorString, (), (override));
+};
+
+}  // namespace libusbwrap
--- a/tests/mocks/MockUsbDeviceFactory.hpp
+++ b/tests/mocks/MockUsbDeviceFactory.hpp
@@ -0,0 +1,41 @@
+/*
+    ptrnt - print labels on linux
+    Copyright (C) 2025  Moritz Martinius
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+ */
+
+#pragma once
+
+#include <gmock/gmock.h>
+
+#include "libusbwrap/interface/IUsbDeviceFactory.hpp"
+
+namespace libusbwrap {
+
+/**
+ * @brief GMock implementation of IUsbDeviceFactory for unit testing
+ *
+ * This mock allows tests to control USB device discovery without
+ * requiring actual libusb context or hardware.
+ */
+class MockUsbDeviceFactory : public IUsbDeviceFactory {
+   public:
+    MOCK_METHOD(bool, init, (), (override));
+    MOCK_METHOD(std::vector<std::unique_ptr<IUsbDevice>>, findAllDevices, (), (override));
+    MOCK_METHOD(std::vector<std::unique_ptr<IUsbDevice>>, findDevices, (uint16_t vid, uint16_t pid), (override));
+};
+
+}  // namespace libusbwrap
--- a/tests/monochrome_test/monochrome_test.cpp
+++ b/tests/monochrome_test/monochrome_test.cpp
@@ -57,9 +57,6 @@ TEST(basic_test, Monochrome_convertWithCustomThreshhold_yieldsMonochromeRespecti
 }

 TEST(basic_test, Monochrome_convertNonAlignedPixels_spillsOverIntoNewByte) {
-    // TODO: We need to find to access the vector without the possiblity of out-of-bounds access
-    // Ideas: constexpr? compile time check?
-    GTEST_SKIP() << "Skipping this test, as ASAN will halt as this is an out-of-bounds access";
    const std::vector<uint8_t> pixels(
        {0xFF, 0x00, 0xFF, 0x00, 0xFF, 0x00, 0xFF, 0x00, 0xFF, 0x00, 0xFF, 0x00, 0xFF, 0x00, 0xFF, 0x00, 0xFF});

--- a/tests/p700_printer_test/p700_printer_test.cpp
+++ b/tests/p700_printer_test/p700_printer_test.cpp
@@ -0,0 +1,169 @@
+/*
+    ptrnt - print labels on linux
+    Copyright (C) 2025  Moritz Martinius
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+ */
+
+#include <gmock/gmock.h>
+#include <gtest/gtest.h>
+
+#include <memory>
+
+#include "graphics/Bitmap.hpp"
+#include "graphics/Monochrome.hpp"
+#include "mocks/MockUsbDevice.hpp"
+#include "printers/P700Printer.hpp"
+
+using ::testing::_;
+using ::testing::DoAll;
+using ::testing::NiceMock;
+using ::testing::Return;
+using ::testing::SetArgPointee;
+
+namespace ptprnt::printer {
+
+// Test fixture for P700Printer tests
+class P700PrinterTest : public ::testing::Test {
+   protected:
+    void SetUp() override {
+        printer    = std::make_unique<P700Printer>();
+        mockUsbDev = std::make_shared<NiceMock<libusbwrap::MockUsbDevice>>();
+
+        // Default mock behaviors
+        ON_CALL(*mockUsbDev, open()).WillByDefault(Return(true));
+        ON_CALL(*mockUsbDev, close()).WillByDefault(Return());
+        ON_CALL(*mockUsbDev, detachKernelDriver(_)).WillByDefault(Return(true));
+        ON_CALL(*mockUsbDev, claimInterface(_)).WillByDefault(Return(true));
+        ON_CALL(*mockUsbDev, releaseInterface(_)).WillByDefault(Return(true));
+        ON_CALL(*mockUsbDev, bulkTransfer(_, _, _, _)).WillByDefault(Return(true));
+        ON_CALL(*mockUsbDev, getUsbId()).WillByDefault(Return(libusbwrap::usbId{0x04f9, 0x2061}));
+    }
+
+    void TearDown() override { printer.reset(); }
+
+    std::unique_ptr<P700Printer> printer;
+    std::shared_ptr<libusbwrap::MockUsbDevice> mockUsbDev;
+};
+
+// Test: Get printer driver name
+TEST_F(P700PrinterTest, GetDriverName) {
+    EXPECT_EQ(printer->getDriverName(), "P700");
+}
+
+// Test: Get printer name
+TEST_F(P700PrinterTest, GetName) {
+    auto name = printer->getName();
+    EXPECT_FALSE(name.empty());
+}
+
+// Test: Get USB ID
+TEST_F(P700PrinterTest, GetUsbId) {
+    auto usbId = printer->getUsbId();
+    EXPECT_EQ(usbId.first, 0x04f9);   // Brother VID
+    EXPECT_EQ(usbId.second, 0x2061);  // P700 PID
+}
+
+// Test: Get printer version
+TEST_F(P700PrinterTest, GetVersion) {
+    auto version = printer->getVersion();
+    EXPECT_FALSE(version.empty());
+}
+
+// Test: Get printer info
+TEST_F(P700PrinterTest, GetPrinterInfo) {
+    auto info = printer->getPrinterInfo();
+    EXPECT_EQ(info.pixelLines, 128);
+    EXPECT_FALSE(info.name.empty());
+}
+
+// Test: Attach USB device
+TEST_F(P700PrinterTest, AttachUsbDevice) {
+    bool result = printer->attachUsbDevice(mockUsbDev);
+
+    EXPECT_TRUE(result);
+}
+
+// Test: Attach USB device with null pointer
+TEST_F(P700PrinterTest, AttachNullUsbDevice) {
+    bool result = printer->attachUsbDevice(nullptr);
+
+    EXPECT_FALSE(result);
+}
+
+// Test: Detach USB device
+TEST_F(P700PrinterTest, DetachUsbDevice) {
+    printer->attachUsbDevice(mockUsbDev);
+
+    bool result = printer->detachUsbDevice();
+
+    EXPECT_TRUE(result);
+}
+
+// Test: Detach when no device attached
+TEST_F(P700PrinterTest, DetachNoDevice) {
+    bool result = printer->detachUsbDevice();
+
+    // Production code returns true when no device is attached (just logs warning)
+    EXPECT_TRUE(result);
+}
+
+// Test: Get printer status without device
+TEST_F(P700PrinterTest, GetStatusNoDevice) {
+    auto status = printer->getPrinterStatus();
+
+    EXPECT_EQ(status.tapeWidthPixel, 0);  // Should be 0 when no device
+}
+
+// Test: Print without attached device
+TEST_F(P700PrinterTest, PrintWithoutDevice) {
+    bool result = printer->print();
+
+    // Should fail when no device is attached
+    EXPECT_FALSE(result);
+}
+
+// Test: Print bitmap without device
+TEST_F(P700PrinterTest, PrintBitmapWithoutDevice) {
+    graphics::Bitmap<graphics::ALPHA8> bitmap(10, 10);
+
+    bool result = printer->printBitmap(bitmap);
+
+    EXPECT_FALSE(result);
+}
+
+// Test: Print monochrome data without device
+TEST_F(P700PrinterTest, PrintMonochromeDataWithoutDevice) {
+    graphics::MonochromeData data;
+    data.width  = 10;
+    data.height = 10;
+    data.bytes  = std::vector<uint8_t>(20, 0xFF);
+    data.stride = 2;
+
+    bool result = printer->printMonochromeData(data);
+
+    EXPECT_FALSE(result);
+}
+
+// Test: Print label with null pointer
+TEST_F(P700PrinterTest, PrintNullLabel) {
+    std::unique_ptr<graphics::ILabel> label = nullptr;
+
+    bool result = printer->printLabel(std::move(label));
+
+    EXPECT_FALSE(result);
+}
+
+}  // namespace ptprnt::printer
--- a/tests/printer_service_test/printer_service_test.cpp
+++ b/tests/printer_service_test/printer_service_test.cpp
@@ -0,0 +1,128 @@
+/*
+    ptrnt - print labels on linux
+    Copyright (C) 2025  Moritz Martinius
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+ */
+
+#include <gmock/gmock.h>
+#include <gtest/gtest.h>
+
+#include <memory>
+#include <vector>
+
+#include "core/PrinterDriverFactory.hpp"
+#include "core/PrinterService.hpp"
+#include "mocks/MockUsbDeviceFactory.hpp"
+
+using ::testing::_;
+using ::testing::Invoke;
+using ::testing::NiceMock;
+using ::testing::Return;
+
+namespace ptprnt::core {
+
+// Helper function to return empty vector of unique_ptrs
+std::vector<std::unique_ptr<libusbwrap::IUsbDevice>> returnEmptyDeviceList() {
+    return {};
+}
+
+// Test fixture for PrinterService tests
+class PrinterServiceTest : public ::testing::Test {
+   protected:
+    void SetUp() override {
+        // Create mock USB device factory
+        auto mockFactory = std::make_unique<NiceMock<libusbwrap::MockUsbDeviceFactory>>();
+        mockFactoryPtr   = mockFactory.get();
+
+        // Default behavior: init succeeds
+        ON_CALL(*mockFactoryPtr, init()).WillByDefault(Return(true));
+
+        // Default behavior: no devices found
+        ON_CALL(*mockFactoryPtr, findAllDevices()).WillByDefault(Invoke(returnEmptyDeviceList));
+
+        // Inject mock factory into service
+        service = std::make_unique<PrinterService>(std::move(mockFactory));
+    }
+
+    void TearDown() override { service.reset(); }
+
+    std::unique_ptr<PrinterService> service;
+    libusbwrap::MockUsbDeviceFactory* mockFactoryPtr;  // Non-owning pointer for expectations
+};
+
+// Test: PrinterService initialization
+TEST_F(PrinterServiceTest, InitializeSuccess) {
+    EXPECT_CALL(*mockFactoryPtr, init()).WillOnce(Return(true));
+
+    EXPECT_TRUE(service->initialize());
+}
+
+// Test: Detect printers when none are connected
+TEST_F(PrinterServiceTest, DetectPrintersNoneFound) {
+    service->initialize();
+
+    // Mock returns empty device list - no real USB enumeration happens
+    EXPECT_CALL(*mockFactoryPtr, findAllDevices()).WillOnce(Invoke(returnEmptyDeviceList));
+
+    auto printers = service->detectPrinters();
+
+    // Should get empty list since mock returns no devices
+    EXPECT_EQ(printers.size(), 0);
+}
+
+// Test: Select printer with auto-detect when none found
+TEST_F(PrinterServiceTest, SelectPrinterAutoNoneFound) {
+    service->initialize();
+
+    // Mock returns empty device list
+    EXPECT_CALL(*mockFactoryPtr, findAllDevices()).WillOnce(Invoke(returnEmptyDeviceList));
+
+    auto printer = service->selectPrinter("auto");
+
+    // Should be nullptr since no printers detected
+    EXPECT_EQ(printer, nullptr);
+    EXPECT_EQ(service->getCurrentPrinter(), nullptr);
+}
+
+// Test: Select non-existent printer by name
+TEST_F(PrinterServiceTest, SelectPrinterByNameNotFound) {
+    service->initialize();
+
+    // This test doesn't need USB mocking since selectPrinter("name")
+    // uses PrinterDriverFactory directly, not USB enumeration
+    auto printer = service->selectPrinter("NonExistentPrinter");
+
+    EXPECT_EQ(printer, nullptr);
+    EXPECT_EQ(service->getCurrentPrinter(), nullptr);
+}
+
+// Test: Get current printer when none selected
+TEST_F(PrinterServiceTest, GetCurrentPrinterNoneSelected) {
+    EXPECT_EQ(service->getCurrentPrinter(), nullptr);
+}
+
+// Test: Print label without selecting printer
+TEST_F(PrinterServiceTest, PrintLabelNoPrinterSelected) {
+    // Create a simple label (we need a valid ILabel pointer)
+    std::unique_ptr<graphics::ILabel> label = nullptr;  // nullptr label for this test
+
+    bool result = service->printLabel(std::move(label));
+
+    // Should fail because no printer is selected
+    EXPECT_FALSE(result);
+}
+
+}  // namespace ptprnt::core
--- a/tests/ptouch_print_test/ptouch_print_test.cpp
+++ b/tests/ptouch_print_test/ptouch_print_test.cpp
@@ -0,0 +1,374 @@
+/*
+    ptrnt - print labels on linux
+    Copyright (C) 2025  Moritz Martinius
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+ */
+
+#include <gmock/gmock.h>
+#include <gtest/gtest.h>
+
+#include "PtouchPrint.hpp"
+#include "cli/interface/ICliParser.hpp"
+#include "core/interface/IPrinterService.hpp"
+#include "printers/interface/IPrinterDriver.hpp"
+
+using ::testing::_;
+using ::testing::NiceMock;
+using ::testing::Return;
+using ::testing::ReturnRef;
+
+namespace ptprnt {
+
+// Mock CLI Parser
+class MockCliParser : public cli::ICliParser {
+   public:
+    MOCK_METHOD(int, parse, (int argc, char** argv), (override));
+    MOCK_METHOD(const cli::CliOptions&, getOptions, (), (const, override));
+
+    cli::CliOptions options;
+};
+
+// Mock Printer Service
+class MockPrinterService : public core::IPrinterService {
+   public:
+    MOCK_METHOD(bool, initialize, (), (override));
+    MOCK_METHOD(std::vector<std::shared_ptr<IPrinterDriver>>, detectPrinters, (), (override));
+    MOCK_METHOD(std::shared_ptr<IPrinterDriver>, selectPrinter, (const std::string& selection), (override));
+    MOCK_METHOD(std::shared_ptr<IPrinterDriver>, getCurrentPrinter, (), (const, override));
+    MOCK_METHOD(bool, printLabel, (std::unique_ptr<graphics::ILabel> label), (override));
+};
+
+// Mock Printer Driver
+class MockPrinterDriver : public IPrinterDriver {
+   public:
+    MOCK_METHOD(std::string_view, getDriverName, (), (override));
+    MOCK_METHOD(std::string_view, getName, (), (override));
+    MOCK_METHOD(libusbwrap::usbId, getUsbId, (), (override));
+    MOCK_METHOD(std::string_view, getVersion, (), (override));
+    MOCK_METHOD(PrinterInfo, getPrinterInfo, (), (override));
+    MOCK_METHOD(PrinterStatus, getPrinterStatus, (), (override));
+    MOCK_METHOD(bool, attachUsbDevice, (std::shared_ptr<libusbwrap::IUsbDevice> usbHndl), (override));
+    MOCK_METHOD(bool, detachUsbDevice, (), (override));
+    MOCK_METHOD(bool, printBitmap, (const graphics::Bitmap<graphics::ALPHA8>& bitmap), (override));
+    MOCK_METHOD(bool, printMonochromeData, (const graphics::MonochromeData& data), (override));
+    MOCK_METHOD(bool, printLabel, (std::unique_ptr<graphics::ILabel> label), (override));
+    MOCK_METHOD(bool, print, (), (override));
+};
+
+class PtouchPrintTest : public ::testing::Test {
+   protected:
+    void SetUp() override {
+        mockCliParser = std::make_unique<NiceMock<MockCliParser>>();
+        mockPrinterService = std::make_unique<NiceMock<MockPrinterService>>();
+
+        // Store raw pointers for setting expectations
+        cliParserPtr = mockCliParser.get();
+        printerServicePtr = mockPrinterService.get();
+
+        // Default behavior: parse succeeds and returns empty options
+        ON_CALL(*cliParserPtr, parse(_, _)).WillByDefault(Return(0));
+        ON_CALL(*cliParserPtr, getOptions()).WillByDefault(ReturnRef(cliParserPtr->options));
+        ON_CALL(*printerServicePtr, initialize()).WillByDefault(Return(true));
+        ON_CALL(*printerServicePtr, printLabel(_)).WillByDefault(Return(true));
+    }
+
+    void TearDown() override {}
+
+    std::unique_ptr<MockCliParser> mockCliParser;
+    std::unique_ptr<MockPrinterService> mockPrinterService;
+    MockCliParser* cliParserPtr;
+    MockPrinterService* printerServicePtr;
+};
+
+// Test: Constructor with default implementations
+TEST_F(PtouchPrintTest, ConstructorDefault) {
+    EXPECT_NO_THROW(PtouchPrint app("v1.0.0"));
+}
+
+// Test: Constructor with custom implementations
+TEST_F(PtouchPrintTest, ConstructorCustom) {
+    EXPECT_NO_THROW({
+        PtouchPrint app("v1.0.0", std::move(mockCliParser), std::move(mockPrinterService));
+    });
+}
+
+// Test: init with successful parse
+TEST_F(PtouchPrintTest, InitSuccess) {
+    PtouchPrint app("v1.0.0", std::move(mockCliParser), std::move(mockPrinterService));
+
+    char* argv[] = {(char*)"ptprnt"};
+    int result = app.init(1, argv);
+
+    EXPECT_EQ(result, 0);
+}
+
+// Test: init with parse returning help (should return 1)
+TEST_F(PtouchPrintTest, InitHelp) {
+    ON_CALL(*cliParserPtr, parse(_, _)).WillByDefault(Return(1));
+
+    PtouchPrint app("v1.0.0", std::move(mockCliParser), std::move(mockPrinterService));
+
+    char* argv[] = {(char*)"ptprnt", (char*)"-h"};
+    int result = app.init(2, argv);
+
+    EXPECT_EQ(result, 1);  // Clean exit
+}
+
+// Test: init with parse error (should return -1)
+TEST_F(PtouchPrintTest, InitParseError) {
+    ON_CALL(*cliParserPtr, parse(_, _)).WillByDefault(Return(-1));
+
+    PtouchPrint app("v1.0.0", std::move(mockCliParser), std::move(mockPrinterService));
+
+    char* argv[] = {(char*)"ptprnt", (char*)"--invalid"};
+    int result = app.init(2, argv);
+
+    EXPECT_EQ(result, -1);  // Error
+}
+
+// Test: init with printer service initialization failure
+TEST_F(PtouchPrintTest, InitPrinterServiceFailure) {
+    ON_CALL(*printerServicePtr, initialize()).WillByDefault(Return(false));
+
+    PtouchPrint app("v1.0.0", std::move(mockCliParser), std::move(mockPrinterService));
+
+    char* argv[] = {(char*)"ptprnt"};
+    int result = app.init(1, argv);
+
+    EXPECT_EQ(result, -1);  // Error
+}
+
+// Test: run with list drivers option
+TEST_F(PtouchPrintTest, RunListDrivers) {
+    cliParserPtr->options.listDrivers = true;
+
+    PtouchPrint app("v1.0.0", std::move(mockCliParser), std::move(mockPrinterService));
+
+    char* argv[] = {(char*)"ptprnt"};
+    app.init(1, argv);
+
+    int result = app.run();
+
+    EXPECT_EQ(result, 0);
+}
+
+// Test: run with no commands (should warn but succeed)
+TEST_F(PtouchPrintTest, RunNoCommands) {
+    auto mockPrinter = std::make_shared<NiceMock<MockPrinterDriver>>();
+    PrinterStatus status{.tapeWidthMm = 12};
+
+    ON_CALL(*mockPrinter, getPrinterStatus()).WillByDefault(Return(status));
+    ON_CALL(*printerServicePtr, selectPrinter(_)).WillByDefault(Return(mockPrinter));
+
+    cliParserPtr->options.commands.clear();
+
+    PtouchPrint app("v1.0.0", std::move(mockCliParser), std::move(mockPrinterService));
+
+    char* argv[] = {(char*)"ptprnt"};
+    app.init(1, argv);
+
+    int result = app.run();
+
+    EXPECT_EQ(result, 0);
+}
+
+// Test: run with printer selection failure
+TEST_F(PtouchPrintTest, RunPrinterSelectionFailure) {
+    ON_CALL(*printerServicePtr, selectPrinter(_)).WillByDefault(Return(nullptr));
+
+    cliParserPtr->options.commands.push_back({cli::CommandType::Text, "Test"});
+
+    PtouchPrint app("v1.0.0", std::move(mockCliParser), std::move(mockPrinterService));
+
+    char* argv[] = {(char*)"ptprnt"};
+    app.init(1, argv);
+
+    int result = app.run();
+
+    EXPECT_EQ(result, -1);
+}
+
+// Test: run with simple text command
+TEST_F(PtouchPrintTest, RunSimpleText) {
+    auto mockPrinter = std::make_shared<NiceMock<MockPrinterDriver>>();
+    PrinterInfo info{.driverName = "Test", .name = "Test", .version = "v1.0", .usbId = {0, 0}, .pixelLines = 128};
+    PrinterStatus status{.tapeWidthMm = 12};
+
+    ON_CALL(*mockPrinter, getPrinterInfo()).WillByDefault(Return(info));
+    ON_CALL(*mockPrinter, getPrinterStatus()).WillByDefault(Return(status));
+    ON_CALL(*mockPrinter, printLabel(_)).WillByDefault(Return(true));
+    ON_CALL(*printerServicePtr, selectPrinter(_)).WillByDefault(Return(mockPrinter));
+
+    cliParserPtr->options.commands.push_back({cli::CommandType::Text, "Hello"});
+
+    PtouchPrint app("v1.0.0", std::move(mockCliParser), std::move(mockPrinterService));
+
+    char* argv[] = {(char*)"ptprnt"};
+    app.init(1, argv);
+
+    int result = app.run();
+
+    EXPECT_EQ(result, 0);
+}
+
+// Test: run with font and text commands
+TEST_F(PtouchPrintTest, RunWithFormatting) {
+    auto mockPrinter = std::make_shared<NiceMock<MockPrinterDriver>>();
+    PrinterInfo info{.driverName = "Test", .name = "Test", .version = "v1.0", .usbId = {0, 0}, .pixelLines = 128};
+    PrinterStatus status{.tapeWidthMm = 12};
+
+    ON_CALL(*mockPrinter, getPrinterInfo()).WillByDefault(Return(info));
+    ON_CALL(*mockPrinter, getPrinterStatus()).WillByDefault(Return(status));
+    ON_CALL(*mockPrinter, printLabel(_)).WillByDefault(Return(true));
+    ON_CALL(*printerServicePtr, selectPrinter(_)).WillByDefault(Return(mockPrinter));
+
+    cliParserPtr->options.commands.push_back({cli::CommandType::Font, "monospace"});
+    cliParserPtr->options.commands.push_back({cli::CommandType::FontSize, "48"});
+    cliParserPtr->options.commands.push_back({cli::CommandType::Text, "Formatted"});
+
+    PtouchPrint app("v1.0.0", std::move(mockCliParser), std::move(mockPrinterService));
+
+    char* argv[] = {(char*)"ptprnt"};
+    app.init(1, argv);
+
+    int result = app.run();
+
+    EXPECT_EQ(result, 0);
+}
+
+// Test: run with alignment commands
+TEST_F(PtouchPrintTest, RunWithAlignment) {
+    auto mockPrinter = std::make_shared<NiceMock<MockPrinterDriver>>();
+    PrinterInfo info{.driverName = "Test", .name = "Test", .version = "v1.0", .usbId = {0, 0}, .pixelLines = 128};
+    PrinterStatus status{.tapeWidthMm = 12};
+
+    ON_CALL(*mockPrinter, getPrinterInfo()).WillByDefault(Return(info));
+    ON_CALL(*mockPrinter, getPrinterStatus()).WillByDefault(Return(status));
+    ON_CALL(*mockPrinter, printLabel(_)).WillByDefault(Return(true));
+    ON_CALL(*printerServicePtr, selectPrinter(_)).WillByDefault(Return(mockPrinter));
+
+    cliParserPtr->options.commands.push_back({cli::CommandType::HAlign, "center"});
+    cliParserPtr->options.commands.push_back({cli::CommandType::VAlign, "middle"});
+    cliParserPtr->options.commands.push_back({cli::CommandType::Text, "Centered"});
+
+    PtouchPrint app("v1.0.0", std::move(mockCliParser), std::move(mockPrinterService));
+
+    char* argv[] = {(char*)"ptprnt"};
+    app.init(1, argv);
+
+    int result = app.run();
+
+    EXPECT_EQ(result, 0);
+}
+
+// Test: run with invalid alignment (should handle gracefully)
+TEST_F(PtouchPrintTest, RunWithInvalidAlignment) {
+    auto mockPrinter = std::make_shared<NiceMock<MockPrinterDriver>>();
+    PrinterInfo info{.driverName = "Test", .name = "Test", .version = "v1.0", .usbId = {0, 0}, .pixelLines = 128};
+    PrinterStatus status{.tapeWidthMm = 12};
+
+    ON_CALL(*mockPrinter, getPrinterInfo()).WillByDefault(Return(info));
+    ON_CALL(*mockPrinter, getPrinterStatus()).WillByDefault(Return(status));
+    ON_CALL(*mockPrinter, printLabel(_)).WillByDefault(Return(true));
+    ON_CALL(*printerServicePtr, selectPrinter(_)).WillByDefault(Return(mockPrinter));
+
+    cliParserPtr->options.commands.push_back({cli::CommandType::HAlign, "invalid"});
+    cliParserPtr->options.commands.push_back({cli::CommandType::Text, "Test"});
+
+    PtouchPrint app("v1.0.0", std::move(mockCliParser), std::move(mockPrinterService));
+
+    char* argv[] = {(char*)"ptprnt"};
+    app.init(1, argv);
+
+    int result = app.run();
+
+    EXPECT_EQ(result, 0);  // Should handle gracefully
+}
+
+// Test: run with new label command
+TEST_F(PtouchPrintTest, RunWithNewLabel) {
+    auto mockPrinter = std::make_shared<NiceMock<MockPrinterDriver>>();
+    PrinterInfo info{.driverName = "Test", .name = "Test", .version = "v1.0", .usbId = {0, 0}, .pixelLines = 128};
+    PrinterStatus status{.tapeWidthMm = 12};
+
+    ON_CALL(*mockPrinter, getPrinterInfo()).WillByDefault(Return(info));
+    ON_CALL(*mockPrinter, getPrinterStatus()).WillByDefault(Return(status));
+    ON_CALL(*mockPrinter, printLabel(_)).WillByDefault(Return(true));
+    ON_CALL(*printerServicePtr, selectPrinter(_)).WillByDefault(Return(mockPrinter));
+
+    cliParserPtr->options.commands.push_back({cli::CommandType::Text, "First"});
+    cliParserPtr->options.commands.push_back({cli::CommandType::NewLabel, ""});
+    cliParserPtr->options.commands.push_back({cli::CommandType::Text, "Second"});
+
+    PtouchPrint app("v1.0.0", std::move(mockCliParser), std::move(mockPrinterService));
+
+    char* argv[] = {(char*)"ptprnt"};
+    app.init(1, argv);
+
+    int result = app.run();
+
+    EXPECT_EQ(result, 0);
+}
+
+// Test: run with verbose option
+TEST_F(PtouchPrintTest, RunWithVerbose) {
+    auto mockPrinter = std::make_shared<NiceMock<MockPrinterDriver>>();
+    PrinterInfo info{.driverName = "Test", .name = "Test", .version = "v1.0", .usbId = {0, 0}, .pixelLines = 128};
+    PrinterStatus status{.tapeWidthMm = 12};
+
+    ON_CALL(*mockPrinter, getPrinterInfo()).WillByDefault(Return(info));
+    ON_CALL(*mockPrinter, getPrinterStatus()).WillByDefault(Return(status));
+    ON_CALL(*mockPrinter, printLabel(_)).WillByDefault(Return(true));
+    ON_CALL(*printerServicePtr, selectPrinter(_)).WillByDefault(Return(mockPrinter));
+
+    cliParserPtr->options.verbose = true;
+    cliParserPtr->options.commands.push_back({cli::CommandType::Text, "Test"});
+
+    PtouchPrint app("v1.0.0", std::move(mockCliParser), std::move(mockPrinterService));
+
+    char* argv[] = {(char*)"ptprnt"};
+    app.init(1, argv);
+
+    int result = app.run();
+
+    EXPECT_EQ(result, 0);
+}
+
+// Test: run with trace option
+TEST_F(PtouchPrintTest, RunWithTrace) {
+    auto mockPrinter = std::make_shared<NiceMock<MockPrinterDriver>>();
+    PrinterInfo info{.driverName = "Test", .name = "Test", .version = "v1.0", .usbId = {0, 0}, .pixelLines = 128};
+    PrinterStatus status{.tapeWidthMm = 12};
+
+    ON_CALL(*mockPrinter, getPrinterInfo()).WillByDefault(Return(info));
+    ON_CALL(*mockPrinter, getPrinterStatus()).WillByDefault(Return(status));
+    ON_CALL(*mockPrinter, printLabel(_)).WillByDefault(Return(true));
+    ON_CALL(*printerServicePtr, selectPrinter(_)).WillByDefault(Return(mockPrinter));
+
+    cliParserPtr->options.trace = true;
+    cliParserPtr->options.commands.push_back({cli::CommandType::Text, "Test"});
+
+    PtouchPrint app("v1.0.0", std::move(mockCliParser), std::move(mockPrinterService));
+
+    char* argv[] = {(char*)"ptprnt"};
+    app.init(1, argv);
+
+    int result = app.run();
+
+    EXPECT_EQ(result, 0);
+}
+
+}  // namespace ptprnt
--- a/tests/usb_device_test/usb_device_test.cpp
+++ b/tests/usb_device_test/usb_device_test.cpp
@@ -0,0 +1,276 @@
+/*
+    ptrnt - print labels on linux
+    Copyright (C) 2025  Moritz Martinius
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+ */
+
+#include <gmock/gmock.h>
+#include <gtest/gtest.h>
+
+#include <memory>
+
+#include "libusb.h"
+#include "libusbwrap/LibUsbTypes.hpp"
+#include "libusbwrap/UsbDevice.hpp"
+#include "mocks/MockLibUsbWrapper.hpp"
+
+using ::testing::_;
+using ::testing::DoAll;
+using ::testing::NiceMock;
+using ::testing::Return;
+using ::testing::SetArgPointee;
+
+namespace libusbwrap {
+
+// Test fixture for UsbDevice tests
+class UsbDeviceTest : public ::testing::Test {
+   protected:
+    void SetUp() override {
+        mockLibUsb = std::make_shared<NiceMock<MockLibUsbWrapper>>();
+
+        // Create mock device pointer
+        mockDevice = reinterpret_cast<libusb_device*>(0x1000);
+
+        // Create mock device handle
+        mockHandle = reinterpret_cast<libusb_device_handle*>(0x2000);
+
+        // Setup device descriptor
+        desc.idVendor  = 0x04f9;  // Brother vendor ID
+        desc.idProduct = 0x2042;  // P700 product ID
+
+        // Default behaviors
+        ON_CALL(*mockLibUsb, open(_, _)).WillByDefault(DoAll(SetArgPointee<1>(mockHandle), Return(0)));
+        ON_CALL(*mockLibUsb, getSpeed(_)).WillByDefault(Return(LIBUSB_SPEED_FULL));
+        ON_CALL(*mockLibUsb, getBusNumber(_)).WillByDefault(Return(1));
+        ON_CALL(*mockLibUsb, getPortNumber(_)).WillByDefault(Return(2));
+        ON_CALL(*mockLibUsb, errorName(_)).WillByDefault(Return("LIBUSB_SUCCESS"));
+    }
+
+    std::shared_ptr<MockLibUsbWrapper> mockLibUsb;
+    libusb_device* mockDevice;
+    libusb_device_handle* mockHandle;
+    libusb_device_descriptor desc{};
+};
+
+// Constructor tests
+TEST_F(UsbDeviceTest, ConstructorWithValidDevice) {
+    EXPECT_NO_THROW({
+        auto device = std::make_unique<UsbDevice>(mockDevice, desc, mockLibUsb);
+        EXPECT_NE(device, nullptr);
+    });
+}
+
+TEST_F(UsbDeviceTest, ConstructorWithNullptrThrows) {
+    EXPECT_THROW({ auto device = std::make_unique<UsbDevice>(nullptr, desc, mockLibUsb); }, std::invalid_argument);
+}
+
+// Open/Close tests
+TEST_F(UsbDeviceTest, OpenSuccess) {
+    auto device = std::make_unique<UsbDevice>(mockDevice, desc, mockLibUsb);
+
+    EXPECT_CALL(*mockLibUsb, open(mockDevice, _)).WillOnce(DoAll(SetArgPointee<1>(mockHandle), Return(0)));
+
+    EXPECT_TRUE(device->open());
+}
+
+TEST_F(UsbDeviceTest, OpenFailure) {
+    auto device = std::make_unique<UsbDevice>(mockDevice, desc, mockLibUsb);
+
+    EXPECT_CALL(*mockLibUsb, open(mockDevice, _)).WillOnce(Return(LIBUSB_ERROR_ACCESS));
+
+    EXPECT_FALSE(device->open());
+    EXPECT_EQ(device->getLastError(), Error::ACCESS);
+}
+
+TEST_F(UsbDeviceTest, CloseWithOpenDevice) {
+    auto device = std::make_unique<UsbDevice>(mockDevice, desc, mockLibUsb);
+    device->open();
+
+    EXPECT_CALL(*mockLibUsb, close(mockHandle)).Times(1);
+    device->close();
+}
+
+TEST_F(UsbDeviceTest, CloseWithoutOpenDevice) {
+    auto device = std::make_unique<UsbDevice>(mockDevice, desc, mockLibUsb);
+
+    // Should not call close if device was never opened
+    EXPECT_CALL(*mockLibUsb, close(_)).Times(0);
+    device->close();
+}
+
+TEST_F(UsbDeviceTest, DestructorClosesOpenDevice) {
+    EXPECT_CALL(*mockLibUsb, close(mockHandle)).Times(1);
+
+    {
+        auto device = std::make_unique<UsbDevice>(mockDevice, desc, mockLibUsb);
+        device->open();
+        // Device goes out of scope, destructor should call close
+    }
+}
+
+// Kernel driver tests
+TEST_F(UsbDeviceTest, DetachKernelDriverWhenActive) {
+    auto device = std::make_unique<UsbDevice>(mockDevice, desc, mockLibUsb);
+    device->open();
+
+    EXPECT_CALL(*mockLibUsb, kernelDriverActive(mockHandle, 0)).WillOnce(Return(1));  // Active
+    EXPECT_CALL(*mockLibUsb, detachKernelDriver(mockHandle, 0)).WillOnce(Return(0));  // Success
+
+    EXPECT_TRUE(device->detachKernelDriver(0));
+}
+
+TEST_F(UsbDeviceTest, DetachKernelDriverWhenNotActive) {
+    auto device = std::make_unique<UsbDevice>(mockDevice, desc, mockLibUsb);
+    device->open();
+
+    EXPECT_CALL(*mockLibUsb, kernelDriverActive(mockHandle, 0)).WillOnce(Return(0));  // Not active
+    EXPECT_CALL(*mockLibUsb, detachKernelDriver(_, _)).Times(0);                      // Should not call detach
+
+    EXPECT_TRUE(device->detachKernelDriver(0));
+}
+
+TEST_F(UsbDeviceTest, DetachKernelDriverFailure) {
+    auto device = std::make_unique<UsbDevice>(mockDevice, desc, mockLibUsb);
+    device->open();
+
+    EXPECT_CALL(*mockLibUsb, kernelDriverActive(mockHandle, 0)).WillOnce(Return(1));  // Active
+    EXPECT_CALL(*mockLibUsb, detachKernelDriver(mockHandle, 0)).WillOnce(Return(LIBUSB_ERROR_NOT_FOUND));
+
+    EXPECT_FALSE(device->detachKernelDriver(0));
+    EXPECT_EQ(device->getLastError(), Error::NOT_FOUND);
+}
+
+// Interface tests
+TEST_F(UsbDeviceTest, ClaimInterfaceSuccess) {
+    auto device = std::make_unique<UsbDevice>(mockDevice, desc, mockLibUsb);
+    device->open();
+
+    EXPECT_CALL(*mockLibUsb, claimInterface(mockHandle, 0)).WillOnce(Return(0));
+
+    EXPECT_TRUE(device->claimInterface(0));
+}
+
+TEST_F(UsbDeviceTest, ClaimInterfaceFailure) {
+    auto device = std::make_unique<UsbDevice>(mockDevice, desc, mockLibUsb);
+    device->open();
+
+    EXPECT_CALL(*mockLibUsb, claimInterface(mockHandle, 0)).WillOnce(Return(LIBUSB_ERROR_BUSY));
+
+    EXPECT_FALSE(device->claimInterface(0));
+    EXPECT_EQ(device->getLastError(), Error::BUSY);
+}
+
+TEST_F(UsbDeviceTest, ReleaseInterfaceSuccess) {
+    auto device = std::make_unique<UsbDevice>(mockDevice, desc, mockLibUsb);
+    device->open();
+
+    EXPECT_CALL(*mockLibUsb, releaseInterface(mockHandle, 0)).WillOnce(Return(0));
+
+    EXPECT_TRUE(device->releaseInterface(0));
+}
+
+TEST_F(UsbDeviceTest, ReleaseInterfaceFailure) {
+    auto device = std::make_unique<UsbDevice>(mockDevice, desc, mockLibUsb);
+    device->open();
+
+    EXPECT_CALL(*mockLibUsb, releaseInterface(mockHandle, 0)).WillOnce(Return(LIBUSB_ERROR_NOT_FOUND));
+
+    EXPECT_FALSE(device->releaseInterface(0));
+    EXPECT_EQ(device->getLastError(), Error::NOT_FOUND);
+}
+
+// Bulk transfer tests
+TEST_F(UsbDeviceTest, BulkTransferSuccess) {
+    auto device = std::make_unique<UsbDevice>(mockDevice, desc, mockLibUsb);
+    device->open();
+
+    std::vector<uint8_t> data = {0x01, 0x02, 0x03};
+    int transferred           = 0;
+
+    EXPECT_CALL(*mockLibUsb, bulkTransfer(mockHandle, 0x02, _, 3, _, 1000))
+        .WillOnce(DoAll(SetArgPointee<4>(3), Return(0)));
+
+    EXPECT_TRUE(device->bulkTransfer(0x02, data, &transferred, 1000));
+}
+
+TEST_F(UsbDeviceTest, BulkTransferFailure) {
+    auto device = std::make_unique<UsbDevice>(mockDevice, desc, mockLibUsb);
+    device->open();
+
+    std::vector<uint8_t> data = {0x01, 0x02, 0x03};
+    int transferred           = 0;
+
+    EXPECT_CALL(*mockLibUsb, bulkTransfer(mockHandle, 0x02, _, 3, _, 1000)).WillOnce(Return(LIBUSB_ERROR_TIMEOUT));
+
+    EXPECT_FALSE(device->bulkTransfer(0x02, data, &transferred, 1000));
+    EXPECT_EQ(device->getLastError(), Error::TIMEOUT);
+}
+
+// Getter tests
+TEST_F(UsbDeviceTest, GetUsbId) {
+    auto device = std::make_unique<UsbDevice>(mockDevice, desc, mockLibUsb);
+
+    auto usbId = device->getUsbId();
+    EXPECT_EQ(usbId.first, 0x04f9);   // vid
+    EXPECT_EQ(usbId.second, 0x2042);  // pid
+}
+
+TEST_F(UsbDeviceTest, GetSpeed) {
+    auto device = std::make_unique<UsbDevice>(mockDevice, desc, mockLibUsb);
+
+    EXPECT_CALL(*mockLibUsb, getSpeed(mockDevice)).WillOnce(Return(LIBUSB_SPEED_HIGH));
+
+    EXPECT_EQ(device->getSpeed(), device::Speed::HIGH);
+}
+
+TEST_F(UsbDeviceTest, GetBusNumber) {
+    auto device = std::make_unique<UsbDevice>(mockDevice, desc, mockLibUsb);
+
+    EXPECT_CALL(*mockLibUsb, getBusNumber(mockDevice)).WillOnce(Return(5));
+
+    EXPECT_EQ(device->getBusNumber(), 5);
+}
+
+TEST_F(UsbDeviceTest, GetPortNumber) {
+    auto device = std::make_unique<UsbDevice>(mockDevice, desc, mockLibUsb);
+
+    EXPECT_CALL(*mockLibUsb, getPortNumber(mockDevice)).WillOnce(Return(3));
+
+    EXPECT_EQ(device->getPortNumber(), 3);
+}
+
+TEST_F(UsbDeviceTest, GetLastError) {
+    auto device = std::make_unique<UsbDevice>(mockDevice, desc, mockLibUsb);
+
+    // Initially no error
+    EXPECT_EQ(device->getLastError(), Error::SUCCESS);
+
+    // After a failed operation
+    EXPECT_CALL(*mockLibUsb, open(_, _)).WillOnce(Return(LIBUSB_ERROR_NO_DEVICE));
+    device->open();
+
+    EXPECT_EQ(device->getLastError(), Error::NO_DEVICE);
+}
+
+TEST_F(UsbDeviceTest, GetLastErrorString) {
+    auto device = std::make_unique<UsbDevice>(mockDevice, desc, mockLibUsb);
+
+    EXPECT_CALL(*mockLibUsb, errorName(static_cast<int>(Error::SUCCESS))).WillOnce(Return("LIBUSB_SUCCESS"));
+
+    EXPECT_EQ(device->getLastErrorString(), "LIBUSB_SUCCESS");
+}
+
+}  // namespace libusbwrap