Refactor cli setup and printer selection logic into separate classes

Reviewed-on: moritz/ptouch-prnt#14

.vscode/settings.json

@@ -88,6 +88,9 @@
   },
   "clangd.onConfigChanged": "restart",
   "cSpell.words": [
+    "fontsize",
+    "halign",
+    "libusb",
     "ptrnt"
   ],
 }

src/PtouchPrint.cpp

@@ -1,4 +1,4 @@
-/* 
+/*
     ptrnt - print labels on linux
     Copyright (C) 2023-2025  Moritz Martinius
 
@@ -18,310 +18,169 @@
  */
 #include "PtouchPrint.hpp"
 
-#include <CLI/App.hpp>
-#include <algorithm>
 #include <fmt/core.h>
-#include <spdlog/common.h>
-#include <spdlog/details/synchronous_factory.h>
-#include <spdlog/logger.h>
-#include <spdlog/sinks/base_sink.h>
 #include <spdlog/sinks/basic_file_sink.h>
 #include <spdlog/sinks/stdout_color_sinks.h>
 #include <spdlog/spdlog.h>
 
-#include <cctype>
-#include <functional>
-#include <memory>
-#include <unordered_set>
-#include <vector>
-
-#include "CLI/Option.hpp"
 #include "PrinterDriverFactory.hpp"
-#include "graphics/Label.hpp"
-#include "graphics/interface/ILabel.hpp"
-#include "libusbwrap/UsbDeviceFactory.hpp"
+#include "cli/CliParser.hpp"
+#include "constants.hpp"
+#include "core/PrinterService.hpp"
+#include "graphics/LabelBuilder.hpp"
 
 namespace ptprnt {
 
-PtouchPrint::PtouchPrint(const char* versionString) : mVersionString{versionString} {}
+PtouchPrint::PtouchPrint(const char* versionString)
+    : mVersionString(versionString),
+      mCliParser(std::make_unique<cli::CliParser>(ptprnt::APP_DESC, versionString)),
+      mPrinterService(std::make_unique<core::PrinterService>()) {}
+
+PtouchPrint::~PtouchPrint() = default;
 
 int PtouchPrint::init(int argc, char** argv) {
-    setupCliParser();
+    // Parse CLI arguments
+    int parseResult = mCliParser->parse(argc, argv);
+    if (parseResult != 0) {
+        // Pass through: positive = clean exit (help/version), negative = error
+        return parseResult;
+    }
 
-    try {
-        mApp.parse(argc, argv);
-    } catch (const CLI::ParseError& e) {
-        mApp.exit(e);
+    // Setup logging based on CLI flags
+    setupLogger();
+
+    // Initialize printer service
+    if (!mPrinterService->initialize()) {
         return -1;
     }
 
-    // Set log level based on flags
-    if (mTraceFlag) {
-        setupLogger(spdlog::level::trace);
-    } else if (mVerboseFlag) {
-        setupLogger(spdlog::level::debug);
-    } else {
-        setupLogger(spdlog::level::warn);
-    }
-
-    if (!mUsbDeviceFactory.init()) {
-        spdlog::error("Could not initialize libusb");
-        return -1;
-    }
     return 0;
 }
 
 int PtouchPrint::run() {
     spdlog::info("ptprnt version {}", mVersionString);
 
-    // Handle --list-all-drivers flag
-    if (mListDriversFlag) {
-        auto driverFactory = std::make_unique<PrinterDriverFactory>();
-        auto drivers       = driverFactory->listAllDrivers();
+    const auto& options = mCliParser->getOptions();
 
-        fmt::print("Available printer drivers:\n");
-        for (const auto& driver : drivers) {
-            fmt::print("  - {}\n", driver);
-        }
-        fmt::print("\nUse with: -p <driver_name> or --printer <driver_name>\n");
-        return 0;
+    // Handle --list-all-drivers
+    if (options.listDrivers) {
+        return handleListDrivers() ? 0 : -1;
     }
 
-    // Determine which printer to use
-    std::shared_ptr<IPrinterDriver> printer = nullptr;
-
-    if (mPrinterSelection != "auto") {
-        // Explicit printer selection by name
-        auto driverFactory = std::make_unique<PrinterDriverFactory>();
-        printer            = driverFactory->createByName(mPrinterSelection);
-
-        if (!printer) {
-            spdlog::error("Failed to create printer driver '{}'", mPrinterSelection);
-            spdlog::info("Use --list-all-drivers to see available drivers");
-            return -1;
-        }
-
-        spdlog::info("Using explicitly selected printer: {}", mPrinterSelection);
-
-        // FakePrinter doesn't need USB device attachment
-        if (mPrinterSelection == "FakePrinter" || mPrinterSelection == "fake") {
-            printer->attachUsbDevice(nullptr);
-        } else {
-            // Real printer needs USB device
-            const auto printerUsbId = printer->getUsbId();
-            auto devices            = mUsbDeviceFactory.findDevices(printerUsbId.first, printerUsbId.second);
-
-            if (devices.empty()) {
-                spdlog::error("No USB device found for printer {}. Is it connected and powered on?", mPrinterSelection);
-                return -1;
-            }
-
-            if (devices.size() > 1) {
-                spdlog::warn("Found more than one device of the same printer on bus. Using first one.");
-            }
-
-            if (!printer->attachUsbDevice(std::move(devices[0]))) {
-                spdlog::error("Failed to attach USB device to printer");
-                return -1;
-            }
-        }
-    } else {
-        // Auto-detect printer from USB devices
-        mDetectedPrinters     = getCompatiblePrinters();
-        auto numFoundPrinters = mDetectedPrinters.size();
-
-        if (numFoundPrinters == 0) {
-            spdlog::error("No compatible printers found, please make sure that they are turned on and connected");
-            spdlog::info("Tip: Use -p FakePrinter for testing without hardware");
-            return -1;
-        } else if (numFoundPrinters > 1) {
-            spdlog::warn("Found more than one compatible printer. Use -p to select explicitly.");
-            return -1;
-        }
-
-        printer                 = mDetectedPrinters[0];
-        const auto printerUsbId = printer->getUsbId();
-        auto devices            = mUsbDeviceFactory.findDevices(printerUsbId.first, printerUsbId.second);
-
-        if (devices.size() != 1) {
-            spdlog::warn("Found more than one device of the same printer on bus. Currently not supported");
-            return -1;
-        }
-
-        if (!printer->attachUsbDevice(std::move(devices[0]))) {
-            spdlog::error("Failed to attach USB device to printer");
-            return -1;
-        }
-    }
-
-    auto status = printer->getPrinterStatus();
-    spdlog::info("Detected tape width is {}mm", status.tapeWidthMm);
-
-    if (0 == mCommands.size()) {
-        spdlog::warn("No command specified, nothing to do...");
-        return 0;
-    }
-
-    auto label = std::make_unique<graphics::Label>(printer->getPrinterInfo().pixelLines);
-    std::string labelText{};
-    // TODO: refactor
-    for (const auto& [cmd, value] : mCommands) {
-        switch (cmd) {
-            case CliCmdType::Text:
-                if (labelText.empty()) {
-                    labelText = value;
-                } else {
-                    labelText = labelText + '\n' + value;
-                }
-                break;
-            case CliCmdType::Font:
-                spdlog::debug("Setting font to {}", value);
-                label->setFontFamily(value);
-                break;
-            case CliCmdType::FontSize:
-                spdlog::debug("Setting font size to {}", std::stod(value));
-                label->setFontSize(std::stod(value));
-                break;
-            case CliCmdType::HAlign:
-                spdlog::debug("Setting text horizontal alignment to {}", value);
-                {
-                    auto hPos = HALignPositionMap.find(value);
-                    if (hPos == HALignPositionMap.end()) {
-                        spdlog::warn("Invalid horizontal alignment specified!");
-                        label->setHAlign(HAlignPosition::UNKNOWN);
-                    } else {
-                        label->setHAlign(hPos->second);
-                    }
-                }
-                break;
-            case CliCmdType::VAlign:
-                spdlog::debug("Setting text vertical alignment to {}", value);
-                {
-                    auto vPos = VALignPositionMap.find(value);
-                    if (vPos == VALignPositionMap.end()) {
-                        spdlog::warn("Invalid verical alignment specified!");
-                        label->setVAlign(VAlignPosition::UNKNOWN);
-                    } else {
-                        label->setVAlign(vPos->second);
-                    }
-                }
-                break;
-            case CliCmdType::None:
-                [[fallthrough]];
-            default:
-                spdlog::warn("This command is currently not supported.");
-                break;
-        }
-    }
-    label->create(labelText);
-    label->writeToPng("./testlabel.png");
-    if (!printer->printLabel(std::move(label))) {
-        spdlog::error("An error occured while printing");
-        return -1;
-    }
-
-    return 0;
+    // Handle printing
+    return handlePrinting() ? 0 : -1;
 }
 
-std::vector<std::shared_ptr<IPrinterDriver>> PtouchPrint::getCompatiblePrinters() {
+void PtouchPrint::setupLogger() {
+    const auto& options = mCliParser->getOptions();
 
-    auto usbDevs       = mUsbDeviceFactory.findAllDevices();
-    auto driverFactory = std::make_unique<PrinterDriverFactory>();
-    std::vector<std::shared_ptr<IPrinterDriver>> foundPrinterDrivers{};
-
-    for (auto& usbDev : usbDevs) {
-        auto driver = driverFactory->create(usbDev->getUsbId());
-        if (driver != nullptr) {
-            foundPrinterDrivers.push_back(driver);
-        }
+    spdlog::level::level_enum level = spdlog::level::warn;
+    if (options.trace) {
+        level = spdlog::level::trace;
+    } else if (options.verbose) {
+        level = spdlog::level::debug;
     }
-    return foundPrinterDrivers;
-}
 
-void PtouchPrint::setupLogger(spdlog::level::level_enum lvl) {
     auto consoleSink = std::make_shared<spdlog::sinks::stdout_color_sink_mt>();
-    consoleSink->set_level(lvl);
-    if (spdlog::level::level_enum::debug == lvl || spdlog::level::level_enum::trace == lvl) {
-        // This will enable file and line number for debug and trace macros
-        // TODO: line number and functions only work with macros
-        consoleSink->set_pattern("%^%L:%$ %v");
-    } else {
-        consoleSink->set_pattern("%^%L:%$ %v");
-    }
+    consoleSink->set_level(level);
+    consoleSink->set_pattern("%^%L:%$ %v");
 
     auto fileSink = std::make_shared<spdlog::sinks::basic_file_sink_mt>("ptprnt.log", true);
     fileSink->set_level(spdlog::level::trace);
     fileSink->set_pattern("%Y-%m-%d %H:%m:%S:%e [pid:%P tid:%t] [%^%l%$] %v (%@)");
+
     std::vector<spdlog::sink_ptr> sinks{consoleSink, fileSink};
     auto logger = std::make_shared<spdlog::logger>("default_logger", sinks.begin(), sinks.end());
     logger->set_level(spdlog::level::trace);
     spdlog::set_default_logger(logger);
 }
 
-// TODO: CLI parsing should be a seperate class/file
-void PtouchPrint::setupCliParser() {
-    auto printVersion = [this](std::size_t) {
-        fmt::print("ptprnt version: {}\n", mVersionString);
-    };
+bool PtouchPrint::handleListDrivers() {
+    auto driverFactory = std::make_unique<PrinterDriverFactory>();
+    auto drivers = driverFactory->listAllDrivers();
 
-    // General options
-    mApp.add_flag("-v,--verbose", mVerboseFlag, "Enable verbose output");
-    mApp.add_flag("--trace", mTraceFlag, "Enable trace output (shows USB communication)");
-    mApp.add_flag("-V,--version", printVersion, "Prints the ptprnt's version");
-
-    // Printer selection
-    mApp.add_option("-p,--printer", mPrinterSelection,
-                    "Select printer driver (default: auto). Use --list-all-drivers to see available options")
-        ->default_val("auto");
-
-    mApp.add_flag("--list-all-drivers", mListDriversFlag, "List all available printer drivers and exit");
-
-    // Text printing options
-    mApp.add_option("-t,--text",
-                    "Text to print (can be used multple times, use formatting options before to "
-                    "influence text layout)")
-        ->group("Printing")
-        ->multi_option_policy(CLI::MultiOptionPolicy::TakeAll)
-        ->trigger_on_parse()
-        ->each([this](std::string text) { mCommands.emplace_back(CliCmdType::Text, text); });
-    mApp.add_option("-f,--font", "Font used for the following text occurences")
-        ->group("Text printing ")
-        ->multi_option_policy(CLI::MultiOptionPolicy::TakeFirst)
-        ->trigger_on_parse()
-        ->each([this](std::string font) { mCommands.emplace_back(CliCmdType::Font, font); });
-    mApp.add_option("-s,--fontsize", "Font size of the following text occurences")
-        ->group("Text printing ")
-        ->multi_option_policy(CLI::MultiOptionPolicy::TakeFirst)
-        ->trigger_on_parse()
-        ->each([this](std::string size) { mCommands.emplace_back(CliCmdType::FontSize, size); });
-    mApp.add_option("--valign", "Vertical alignment of the following text occurences")
-        ->group("Text printing ")
-        ->multi_option_policy(CLI::MultiOptionPolicy::TakeFirst)
-        ->trigger_on_parse()
-        ->transform([](std::string in) -> std::string {
-            std::unordered_set<std::string> validValignOptions{"top", "middle", "bottom"};
-            std::ranges::transform(in, in.begin(), [](unsigned char c) { return std::tolower(c); });
-            if (validValignOptions.find(in) == validValignOptions.end()) {
-                return {""};
-            }
-            return in;
-        })
-        ->each([this](std::string valign) { mCommands.emplace_back(CliCmdType::VAlign, valign); });
-    mApp.add_option("--halign", "Vertical alignment of the following text occurences")
-        ->group("Text printing ")
-        ->multi_option_policy(CLI::MultiOptionPolicy::TakeFirst)
-        ->trigger_on_parse()
-        ->transform([](std::string in) -> std::string {
-            std::unordered_set<std::string> validValignOptions{"left", "center", "right", "justify"};
-            std::transform(in.begin(), in.end(), in.begin(), [](unsigned char c) { return std::tolower(c); });
-            if (validValignOptions.find(in) == validValignOptions.end()) {
-                return {""};
-            }
-            return in;
-        })
-        ->each([this](std::string halign) { mCommands.emplace_back(CliCmdType::HAlign, halign); });
-
-    // Image options
-    mApp.add_option("-i,--image", "Image to print. Excludes all text printing ")->group("Image printing");
+    fmt::print("Available printer drivers:\n");
+    for (const auto& driver : drivers) {
+        fmt::print("  - {}\n", driver);
+    }
+    fmt::print("\nUse with: -p <driver_name> or --printer <driver_name>\n");
+    return true;
 }
-}  // namespace ptprnt
+
+bool PtouchPrint::handlePrinting() {
+    const auto& options = mCliParser->getOptions();
+
+    // Select printer
+    auto printer = mPrinterService->selectPrinter(options.printerSelection);
+    if (!printer) {
+        spdlog::error("Failed to select printer");
+        return false;
+    }
+
+    // Get printer status
+    auto status = printer->getPrinterStatus();
+    spdlog::info("Detected tape width is {}mm", status.tapeWidthMm);
+
+    // Check if there are any commands
+    if (options.commands.empty()) {
+        spdlog::warn("No command specified, nothing to do...");
+        return true;
+    }
+
+    // Build label using LabelBuilder
+    graphics::LabelBuilder labelBuilder(printer->getPrinterInfo().pixelLines);
+
+    for (const auto& [cmdType, value] : options.commands) {
+        switch (cmdType) {
+            case cli::CommandType::Text:
+                labelBuilder.addText(value + "\n");
+                break;
+            case cli::CommandType::Font:
+                spdlog::debug("Setting font to {}", value);
+                labelBuilder.setFontFamily(value);
+                break;
+            case cli::CommandType::FontSize:
+                spdlog::debug("Setting font size to {}", std::stod(value));
+                labelBuilder.setFontSize(std::stod(value));
+                break;
+            case cli::CommandType::HAlign: {
+                spdlog::debug("Setting text horizontal alignment to {}", value);
+                auto hPos = HALignPositionMap.find(value);
+                if (hPos == HALignPositionMap.end()) {
+                    spdlog::warn("Invalid horizontal alignment specified!");
+                    labelBuilder.setHAlign(HAlignPosition::UNKNOWN);
+                } else {
+                    labelBuilder.setHAlign(hPos->second);
+                }
+                break;
+            }
+            case cli::CommandType::VAlign: {
+                spdlog::debug("Setting text vertical alignment to {}", value);
+                auto vPos = VALignPositionMap.find(value);
+                if (vPos == VALignPositionMap.end()) {
+                    spdlog::warn("Invalid vertical alignment specified!");
+                    labelBuilder.setVAlign(VAlignPosition::UNKNOWN);
+                } else {
+                    labelBuilder.setVAlign(vPos->second);
+                }
+                break;
+            }
+            case cli::CommandType::None:
+                [[fallthrough]];
+            default:
+                spdlog::warn("This command is currently not supported.");
+                break;
+        }
+    }
+
+    // Build and print the label
+    auto label = labelBuilder.build();
+    if (!mPrinterService->printLabel(std::move(label))) {
+        spdlog::error("An error occurred while printing");
+        return false;
+    }
+
+    return true;
+}
+
+}  // namespace ptprnt

src/PtouchPrint.hpp

@@ -1,4 +1,4 @@
-/* 
+/*
     ptrnt - print labels on linux
     Copyright (C) 2023-2025  Moritz Martinius
 
@@ -19,49 +19,62 @@
 
 #pragma once
 
-#include <CLI/CLI.hpp>
-#include <spdlog/common.h>
-#include <spdlog/spdlog.h>
+#include <memory>
+#include <string>
 
-#include "constants.hpp"
-#include "interface/IPrinterDriver.hpp"
-#include "libusbwrap/UsbDeviceFactory.hpp"
+namespace ptprnt::cli {
+class CliParser;
+}
+
+namespace ptprnt::core {
+class PrinterService;
+}
 
 namespace ptprnt {
-enum class CliCmdType { None = 0, Text = 1, FontSize = 2, Font = 3, VAlign = 4, HAlign = 5 };
-using CliCmd = std::pair<CliCmdType, std::string>;
 
+/**
+ * @brief Main application class for ptprnt
+ *
+ * Acts as a thin glue layer coordinating CLI parsing and core printer functionality.
+ * Separates CLI frontend concerns from the core library.
+ */
 class PtouchPrint {
    public:
+    /**
+     * @brief Construct the application
+     * @param versionString Version string to display
+     */
     PtouchPrint(const char* versionString);
-    ~PtouchPrint() = default;
+    ~PtouchPrint();  // Must be defined in .cpp where complete types are visible
 
-    // This is basically a singelton application class, no need to copy or move
+    // This is basically a singleton application class, no need to copy or move
     PtouchPrint(const PtouchPrint&)            = delete;
     PtouchPrint& operator=(const PtouchPrint&) = delete;
     PtouchPrint(PtouchPrint&&)                 = delete;
     PtouchPrint& operator=(PtouchPrint&&)      = delete;
 
+    /**
+     * @brief Initialize the application
+     * @param argc Argument count
+     * @param argv Argument values
+     * @return 0 on success, non-zero on error
+     */
     int init(int argc, char** argv);
+
+    /**
+     * @brief Run the application
+     * @return 0 on success, non-zero on error
+     */
     int run();
 
    private:
-    // methods
-    void setupLogger(spdlog::level::level_enum lvl);
-    void setupCliParser();
-    std::vector<std::shared_ptr<IPrinterDriver>> getCompatiblePrinters();
+    void setupLogger();
+    bool handleListDrivers();
+    bool handlePrinting();
 
-    // member variables
-    CLI::App mApp{ptprnt::APP_DESC};
-    libusbwrap::UsbDeviceFactory mUsbDeviceFactory{};
-    std::vector<std::shared_ptr<IPrinterDriver>> mDetectedPrinters{};
-    std::vector<CliCmd> mCommands{};
-    std::string mVersionString = "";
-
-    // CLI flags and options
-    bool mVerboseFlag = false;
-    bool mTraceFlag = false;
-    std::string mPrinterSelection = "auto";
-    bool mListDriversFlag = false;
+    std::string mVersionString;
+    std::unique_ptr<cli::CliParser> mCliParser;
+    std::unique_ptr<core::PrinterService> mPrinterService;
 };
-}  // namespace ptprnt
+
+}  // namespace ptprnt

src/cli/CliParser.cpp

@@ -0,0 +1,93 @@
+/*
+    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 "CliParser.hpp"
+
+#include <fmt/core.h>
+
+namespace ptprnt::cli {
+
+CliParser::CliParser(const std::string& appDescription, std::string versionString)
+    : mApp(appDescription), mVersionString(std::move(versionString)) {
+    setupParser();
+}
+
+int CliParser::parse(int argc, char** argv) {
+    try {
+        mApp.parse(argc, argv);
+    } catch (const CLI::CallForHelp& e) {
+        // User requested help - display it and signal clean exit
+        mApp.exit(e);
+        return 1;  // Signal: exit cleanly
+    } catch (const CLI::CallForVersion&) {
+        // User requested version - already displayed by callback
+        return 1;  // Signal: exit cleanly
+    } catch (const CLI::ParseError& e) {
+        // Parse error - display error message
+        mApp.exit(e);
+        return -1;  // Signal: error
+    }
+    return 0;
+}
+
+void CliParser::setupParser() {
+    // Version callback
+    auto printVersion = [this](std::size_t) {
+        fmt::print("ptprnt version: {}\n", mVersionString);
+        throw CLI::CallForVersion();
+    };
+
+    // General options
+    mApp.add_flag("-v,--verbose", mOptions.verbose, "Enable verbose output");
+    mApp.add_flag("--trace", mOptions.trace, "Enable trace output (shows USB communication)");
+    mApp.add_flag("-V,--version", printVersion, "Prints the ptprnt's version");
+
+    // Printer selection
+    mApp.add_option("-p,--printer", mOptions.printerSelection,
+                    "Select printer driver (default: auto). Use --list-all-drivers to see available options")
+        ->default_val("auto");
+
+    mApp.add_flag("--list-all-drivers", mOptions.listDrivers, "List all available printer drivers and exit");
+
+    // Text printing options
+    // Note: CLI11 options are processed in order when using ->each() with callbacks
+    mApp.add_option("-t,--text",
+                    "Text to print (can be used multiple times, use formatting options before to influence text layout)")
+        ->multi_option_policy(CLI::MultiOptionPolicy::TakeAll)
+        ->each([this](const std::string& text) { mOptions.commands.emplace_back(CommandType::Text, text); });
+
+    // Text formatting options
+    mApp.add_option("-f,--font", "Font used for the following text occurrences")
+        ->multi_option_policy(CLI::MultiOptionPolicy::TakeAll)
+        ->each([this](const std::string& font) { mOptions.commands.emplace_back(CommandType::Font, font); });
+
+    mApp.add_option("-s,--fontsize", "Font size of the following text occurrences")
+        ->multi_option_policy(CLI::MultiOptionPolicy::TakeAll)
+        ->each([this](const std::string& size) { mOptions.commands.emplace_back(CommandType::FontSize, size); });
+
+    mApp.add_option("--valign", "Vertical alignment of the following text occurrences")
+        ->multi_option_policy(CLI::MultiOptionPolicy::TakeAll)
+        ->each([this](const std::string& align) { mOptions.commands.emplace_back(CommandType::VAlign, align); });
+
+    mApp.add_option("--halign", "Horizontal alignment of the following text occurrences")
+        ->multi_option_policy(CLI::MultiOptionPolicy::TakeAll)
+        ->each([this](const std::string& align) { mOptions.commands.emplace_back(CommandType::HAlign, align); });
+}
+
+}  // namespace ptprnt::cli

src/cli/CliParser.hpp

@@ -0,0 +1,94 @@
+/*
+    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 <CLI/CLI.hpp>
+
+#include <string>
+#include <vector>
+
+namespace ptprnt::cli {
+
+/**
+ * @brief Types of CLI commands that can be issued
+ */
+enum class CommandType { None = 0, Text = 1, FontSize = 2, Font = 3, VAlign = 4, HAlign = 5 };
+
+/**
+ * @brief A command with its type and value
+ */
+using Command = std::pair<CommandType, std::string>;
+
+/**
+ * @brief Parsed CLI options and commands
+ */
+struct CliOptions {
+    bool verbose{false};
+    bool trace{false};
+    bool listDrivers{false};
+    std::string printerSelection{"auto"};
+    std::vector<Command> commands{};
+};
+
+/**
+ * @brief CLI argument parser for ptprnt
+ *
+ * Handles all command-line argument parsing using CLI11.
+ * Separates CLI concerns from core library functionality.
+ */
+class CliParser {
+   public:
+    /**
+     * @brief Construct a CLI parser
+     * @param appDescription Application description for help text
+     * @param versionString Version string to display
+     */
+    CliParser(const std::string& appDescription, std::string versionString);
+
+    ~CliParser() = default;
+
+    CliParser(const CliParser&)            = delete;
+    CliParser& operator=(const CliParser&) = delete;
+    CliParser(CliParser&&)                 = delete;
+    CliParser& operator=(CliParser&&)      = delete;
+
+    /**
+     * @brief Parse command line arguments
+     * @param argc Argument count
+     * @param argv Argument values
+     * @return 0 on success, positive value if should exit immediately (help/version), negative on error
+     */
+    int parse(int argc, char** argv);
+
+    /**
+     * @brief Get the parsed options
+     * @return Reference to parsed options
+     */
+    [[nodiscard]] const CliOptions& getOptions() const { return mOptions; }
+
+   private:
+    void setupParser();
+
+    CLI::App mApp;
+    std::string mVersionString;
+    CliOptions mOptions;
+};
+
+}  // namespace ptprnt::cli

src/core/PrinterService.cpp

@@ -0,0 +1,95 @@
+/*
+    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 "PrinterService.hpp"
+
+#include <spdlog/spdlog.h>
+
+#include "PrinterDriverFactory.hpp"
+
+namespace ptprnt::core {
+
+PrinterService::PrinterService() = default;
+
+bool PrinterService::initialize() {
+    if (!mUsbDeviceFactory.init()) {
+        spdlog::error("Could not initialize libusb");
+        return false;
+    }
+    return true;
+}
+
+std::vector<std::shared_ptr<IPrinterDriver>> PrinterService::detectPrinters() {
+    spdlog::debug("Detecting printers...");
+
+    auto usbDevs = mUsbDeviceFactory.findAllDevices();
+    auto driverFactory = std::make_unique<PrinterDriverFactory>();
+    mDetectedPrinters.clear();
+
+    for (auto& usbDev : usbDevs) {
+        auto driver = driverFactory->create(usbDev->getUsbId());
+        if (driver != nullptr) {
+            mDetectedPrinters.push_back(driver);
+        }
+    }
+
+    spdlog::debug("Found {} compatible printer(s)", mDetectedPrinters.size());
+    return mDetectedPrinters;
+}
+
+std::shared_ptr<IPrinterDriver> PrinterService::selectPrinter(const std::string& printerName) {
+    if (mDetectedPrinters.empty()) {
+        detectPrinters();
+    }
+
+    if (mDetectedPrinters.empty()) {
+        spdlog::error("No compatible printers detected");
+        return nullptr;
+    }
+
+    // Auto-select first printer
+    if (printerName == "auto") {
+        mCurrentPrinter = mDetectedPrinters.front();
+        spdlog::info("Auto-selected printer: {}", mCurrentPrinter->getName());
+        return mCurrentPrinter;
+    }
+
+    // Select printer by name
+    for (auto& printer : mDetectedPrinters) {
+        if (printer->getDriverName() == printerName) {
+            mCurrentPrinter = printer;
+            spdlog::info("Using explicitly selected printer: {}", printerName);
+            return mCurrentPrinter;
+        }
+    }
+
+    spdlog::error("Printer '{}' not found", printerName);
+    return nullptr;
+}
+
+bool PrinterService::printLabel(std::unique_ptr<graphics::ILabel> label) {
+    if (!mCurrentPrinter) {
+        spdlog::error("No printer selected");
+        return false;
+    }
+
+    return mCurrentPrinter->printLabel(std::move(label));
+}
+
+}  // namespace ptprnt::core

src/core/PrinterService.hpp

@@ -0,0 +1,87 @@
+/*
+    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 <memory>
+#include <string>
+#include <vector>
+
+#include "interface/IPrinterDriver.hpp"
+#include "libusbwrap/UsbDeviceFactory.hpp"
+
+namespace ptprnt::core {
+
+/**
+ * @brief Core service for printer operations
+ *
+ * Provides the core library functionality for:
+ * - Detecting printers
+ * - Selecting printers
+ * - Building and printing labels
+ */
+class PrinterService {
+   public:
+    PrinterService();
+    ~PrinterService() = default;
+
+    PrinterService(const PrinterService&)            = delete;
+    PrinterService& operator=(const PrinterService&) = delete;
+    PrinterService(PrinterService&&)                 = delete;
+    PrinterService& operator=(PrinterService&&)      = delete;
+
+    /**
+     * @brief Initialize USB device factory
+     * @return true on success, false on failure
+     */
+    bool initialize();
+
+    /**
+     * @brief Detect all compatible printers
+     * @return Vector of detected printers
+     */
+    std::vector<std::shared_ptr<IPrinterDriver>> detectPrinters();
+
+    /**
+     * @brief Select a printer by name or auto-detect
+     * @param printerName Printer driver name, or "auto" for first detected
+     * @return Printer driver, or nullptr if not found
+     */
+    std::shared_ptr<IPrinterDriver> selectPrinter(const std::string& printerName);
+
+    /**
+     * @brief Get the currently selected printer
+     * @return Current printer, or nullptr if none selected
+     */
+    [[nodiscard]] std::shared_ptr<IPrinterDriver> getCurrentPrinter() const { return mCurrentPrinter; }
+
+    /**
+     * @brief Print a label
+     * @param label The label to print
+     * @return true on success, false on failure
+     */
+    bool printLabel(std::unique_ptr<graphics::ILabel> label);
+
+   private:
+    libusbwrap::UsbDeviceFactory mUsbDeviceFactory;
+    std::vector<std::shared_ptr<IPrinterDriver>> mDetectedPrinters;
+    std::shared_ptr<IPrinterDriver> mCurrentPrinter;
+};
+
+}  // namespace ptprnt::core

src/graphics/LabelBuilder.cpp

@@ -0,0 +1,95 @@
+/*
+    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 "LabelBuilder.hpp"
+
+#include <spdlog/spdlog.h>
+
+#include "Label.hpp"
+
+namespace ptprnt::graphics {
+
+LabelBuilder::LabelBuilder(int printerHeight) : mPrinterHeight(printerHeight) {
+    reset();
+}
+
+ILabelBuilder& LabelBuilder::addText(const std::string& text) {
+    if (!text.empty()) {
+        if (!mAccumulatedText.empty()) {
+            // Add a newline if the label already has some text accumulated
+            mAccumulatedText += '\n';
+        }
+        mAccumulatedText += text;
+        spdlog::debug("LabelBuilder: Added text '{}', total length: {}", text, mAccumulatedText.length());
+    }
+    return *this;
+}
+
+ILabelBuilder& LabelBuilder::setFontFamily(const std::string& fontFamily) {
+    mCurrentFontFamily = fontFamily;
+    spdlog::debug("LabelBuilder: Set font family to '{}'", fontFamily);
+    return *this;
+}
+
+ILabelBuilder& LabelBuilder::setFontSize(double fontSize) {
+    mCurrentFontSize = fontSize;
+    spdlog::debug("LabelBuilder: Set font size to {}", fontSize);
+    return *this;
+}
+
+ILabelBuilder& LabelBuilder::setHAlign(HAlignPosition hAlign) {
+    mCurrentHAlign = hAlign;
+    spdlog::debug("LabelBuilder: Set horizontal alignment to {}", static_cast<int>(hAlign));
+    return *this;
+}
+
+ILabelBuilder& LabelBuilder::setVAlign(VAlignPosition vAlign) {
+    mCurrentVAlign = vAlign;
+    spdlog::debug("LabelBuilder: Set vertical alignment to {}", static_cast<int>(vAlign));
+    return *this;
+}
+
+std::unique_ptr<ILabel> LabelBuilder::build() {
+    spdlog::debug("LabelBuilder: Building label with text: '{}'", mAccumulatedText);
+
+    auto label = std::make_unique<Label>(mPrinterHeight);
+
+    // Apply current formatting settings
+    label->setFontFamily(mCurrentFontFamily);
+    label->setFontSize(mCurrentFontSize);
+    label->setHAlign(mCurrentHAlign);
+    label->setVAlign(mCurrentVAlign);
+
+    // Create the label with accumulated text
+    label->create(mAccumulatedText);
+
+    return label;
+}
+
+ILabelBuilder& LabelBuilder::reset() {
+    mAccumulatedText.clear();
+    mCurrentFontFamily = DEFAULT_FONT_FAMILY;
+    mCurrentFontSize   = DEFAULT_FONT_SIZE;
+    mCurrentHAlign     = HAlignPosition::LEFT;
+    mCurrentVAlign     = VAlignPosition::MIDDLE;
+    spdlog::debug("LabelBuilder: Reset to default state");
+    return *this;
+}
+
+}  // namespace ptprnt::graphics

src/graphics/LabelBuilder.hpp

@@ -0,0 +1,64 @@
+/*
+    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 <memory>
+#include <string>
+#include <vector>
+
+#include "interface/ILabel.hpp"
+#include "interface/ILabelBuilder.hpp"
+
+namespace ptprnt::graphics {
+
+/**
+ * @brief Concrete implementation of ILabelBuilder
+ *
+ * Builds labels by accumulating text segments with formatting options,
+ * then creates a Label instance with all the collected content.
+ */
+class LabelBuilder : public ILabelBuilder {
+   public:
+    /**
+     * @brief Construct a LabelBuilder for a specific printer height
+     * @param printerHeight Height of the printer in pixels (tape width)
+     */
+    explicit LabelBuilder(int printerHeight);
+
+    ~LabelBuilder() override = default;
+
+    ILabelBuilder& addText(const std::string& text) override;
+    ILabelBuilder& setFontFamily(const std::string& fontFamily) override;
+    ILabelBuilder& setFontSize(double fontSize) override;
+    ILabelBuilder& setHAlign(HAlignPosition hAlign) override;
+    ILabelBuilder& setVAlign(VAlignPosition vAlign) override;
+    std::unique_ptr<ILabel> build() override;
+    ILabelBuilder& reset() override;
+
+   private:
+    int mPrinterHeight;
+    std::string mAccumulatedText;
+    std::string mCurrentFontFamily{DEFAULT_FONT_FAMILY};
+    double mCurrentFontSize{DEFAULT_FONT_SIZE};
+    HAlignPosition mCurrentHAlign{HAlignPosition::LEFT};
+    VAlignPosition mCurrentVAlign{VAlignPosition::MIDDLE};
+};
+
+}  // namespace ptprnt::graphics

src/graphics/interface/ILabelBuilder.hpp

@@ -0,0 +1,88 @@
+/*
+    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 <memory>
+#include <string>
+
+#include "ILabel.hpp"
+
+namespace ptprnt::graphics {
+
+/**
+ * @brief Builder interface for creating labels with text and formatting options
+ *
+ * The LabelBuilder provides a fluent API for constructing labels with various
+ * text elements, fonts, sizes, and alignment options. It separates the construction
+ * logic from the label rendering logic, making it easier to test and maintain.
+ */
+class ILabelBuilder {
+   public:
+    virtual ~ILabelBuilder() = default;
+
+    /**
+     * @brief Add text to the label with current formatting settings
+     * @param text The text to add
+     * @return Reference to this builder for method chaining
+     */
+    virtual ILabelBuilder& addText(const std::string& text) = 0;
+
+    /**
+     * @brief Set the font family for subsequent text additions
+     * @param fontFamily Font family name (e.g., "sans", "serif", "monospace")
+     * @return Reference to this builder for method chaining
+     */
+    virtual ILabelBuilder& setFontFamily(const std::string& fontFamily) = 0;
+
+    /**
+     * @brief Set the font size for subsequent text additions
+     * @param fontSize Font size in points
+     * @return Reference to this builder for method chaining
+     */
+    virtual ILabelBuilder& setFontSize(double fontSize) = 0;
+
+    /**
+     * @brief Set horizontal alignment for subsequent text additions
+     * @param hAlign Horizontal alignment position
+     * @return Reference to this builder for method chaining
+     */
+    virtual ILabelBuilder& setHAlign(HAlignPosition hAlign) = 0;
+
+    /**
+     * @brief Set vertical alignment for subsequent text additions
+     * @param vAlign Vertical alignment position
+     * @return Reference to this builder for method chaining
+     */
+    virtual ILabelBuilder& setVAlign(VAlignPosition vAlign) = 0;
+
+    /**
+     * @brief Build and return the label with all added content
+     * @return Unique pointer to the constructed label
+     */
+    virtual std::unique_ptr<ILabel> build() = 0;
+
+    /**
+     * @brief Reset the builder to initial state
+     * @return Reference to this builder for method chaining
+     */
+    virtual ILabelBuilder& reset() = 0;
+};
+
+}  // namespace ptprnt::graphics

src/main.cpp

@@ -22,7 +22,10 @@ int main(int argc, char** argv) {
     ptprnt::PtouchPrint ptouchprnt(PROJ_VERSION);
     int ret = ptouchprnt.init(argc, argv);
     if (ret != 0) {
-        return ret;
+        // Non-zero from init means don't continue
+        // Positive values = clean exit (help/version)
+        // Negative values = error
+        return ret > 0 ? 0 : ret;
     }
     return ptouchprnt.run();
 }

src/meson.build

@@ -12,7 +12,10 @@ ptprnt_hpps = files (
     'PrinterDriverFactory.hpp',
     'graphics/Bitmap.hpp',
     'graphics/Label.hpp',
-    'graphics/Monochrome.hpp'
+    'graphics/LabelBuilder.hpp',
+    'graphics/Monochrome.hpp',
+    'cli/CliParser.hpp',
+    'core/PrinterService.hpp'
 )
 
 ptprnt_srcs = files (
@@ -21,8 +24,11 @@ ptprnt_srcs = files (
     'printers/P700Printer.cpp',
     'printers/FakePrinter.cpp',
     'graphics/Label.cpp',
+    'graphics/LabelBuilder.cpp',
     'graphics/Bitmap.cpp',
     'graphics/Monochrome.cpp',
     'libusbwrap/UsbDeviceFactory.cpp',
     'libusbwrap/UsbDevice.cpp',
+    'cli/CliParser.cpp',
+    'core/PrinterService.cpp'
 )