Generate labels with pangocairo (#8)

Goal of this PR is to have some basic labels generated with pangocairo
- size of the canvas should be matching the input text and grow/shrink accordingly
- basic formatting options like fontsize and align should be working

Reviewed-on: moritz/ptouch-prnt#8

src/graphics/Monochrome.hpp

@@ -1,6 +1,6 @@
 /* 
     ptrnt - print labels on linux
-    Copyright (C) 2023  Moritz Martinius
+    Copyright (C) 2023-2025  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
@@ -20,22 +20,81 @@
 #pragma once
 
 #include <cstdint>
+#include <span>
+#include <vector>
 
 #include "graphics/Bitmap.hpp"
 
 namespace ptprnt::graphics {
-class Monochrome {
-   public:
-    Monochrome(const std::vector<uint8_t>& grayscale);
-    ~Monochrome() = default;
 
-    void setThreshold(uint8_t);
+enum class Orientation {
+    LANDSCAPE         = 0,  // 0 degrees
+    PORTRAIT          = 1,  // 90 degrees clockwise
+    LANDSCAPE_FLIPPED = 2,  // 180 degrees
+    PORTRAIT_FLIPPED  = 3   // 270 degrees clockwise (90 counter-clockwise)
+};
+
+class MonochromeData {
+   public:
+    // Constructors
+    MonochromeData() : stride(0), orientation(Orientation::LANDSCAPE), width(0), height(0) {}
+
+    MonochromeData(std::vector<uint8_t> data, uint32_t stride_bytes, Orientation orient = Orientation::LANDSCAPE,
+                   uint32_t w = 0, uint32_t h = 0)
+        : bytes(std::move(data)), stride(stride_bytes), orientation(orient), width(w), height(h) {}
+
+    // Constructor from grayscale data (replaces old Monochrome class)
+    MonochromeData(const std::vector<uint8_t>& grayscale, uint32_t width, uint32_t height,
+                   Orientation orient = Orientation::LANDSCAPE);
+    MonochromeData(const std::span<uint8_t> grayscale, uint32_t width, uint32_t height,
+                   Orientation orient = Orientation::LANDSCAPE);
+
+    ~MonochromeData() = default;
+
+    // Copy constructor and assignment
+    MonochromeData(const MonochromeData&)            = default;
+    MonochromeData& operator=(const MonochromeData&) = default;
+
+    // Move constructor and assignment
+    MonochromeData(MonochromeData&&)            = default;
+    MonochromeData& operator=(MonochromeData&&) = default;
+
+    // Configuration methods
+    void setThreshold(uint8_t threshold);
     void invert(bool shouldInvert);
-    std::vector<uint8_t> get();
+
+    // Get processed monochrome data
+    MonochromeData get();
+
+    // Transform the image data to the target orientation
+    void transformTo(Orientation targetOrientation);
+
+    // Visualize the monochrome data on stdout
+    void visualize() const;
+
+    // Helper methods for orientation transformations
+    [[nodiscard]] bool getBit(uint32_t x, uint32_t y) const;
+    void setBit(uint32_t x, uint32_t y, bool value);
+    [[nodiscard]] std::vector<uint8_t> createRotatedData(Orientation targetOrientation) const;
+
+    // Public member access for backward compatibility
+    std::vector<uint8_t> bytes;
+    uint32_t stride;
+    Orientation orientation;
+    uint32_t width;   // Width in pixels
+    uint32_t height;  // Height in pixels
 
    private:
-    const std::vector<uint8_t>& mPixels;
-    uint8_t mThreshhold = 127;
-    bool mShouldInvert  = false;
+    // Processing parameters (for old Monochrome class compatibility)
+    std::vector<uint8_t> mPixels;  // Original grayscale pixels
+    uint8_t mThreshold = UINT8_MAX / 2;
+    bool mShouldInvert = false;
+    bool mIsProcessed  = false;  // Flag to indicate if conversion has been done
+
+    // Helper method to convert grayscale to monochrome
+    void processGrayscaleToMonochrome();
 };
+
+// For backward compatibility, create a type alias
+using Monochrome = MonochromeData;
 }  // namespace ptprnt::graphics