midi_keyboard.hpp

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#pragma once
 
#include <functional>
#include <pulp/view/view.hpp>
#include <set>
 
namespace pulp::view {
 
// ── MidiKeyboard ────────────────────────────────────────────────────────────
// Piano keyboard widget for note input/display.
 
class MidiKeyboard : public View {
  public:
    MidiKeyboard();
 
    // Range (MIDI note numbers 0-127)
    void set_range(int first_note, int last_note);
    int first_note() const {
        return first_note_;
    }
    int last_note() const {
        return last_note_;
    }
 
    // Active/held notes (for display from external MIDI)
    void note_on(int note, float velocity = 1.0f);
    void note_off(int note);
    void all_notes_off();
    bool is_note_on(int note) const;
 
    // Interaction
    std::function<void(int note, float velocity)> on_note_on;
    std::function<void(int note)> on_note_off;

    enum class Orientation {
        horizontal,
        vertical,                
        vertical_chromatic_rows, 
    };

    void set_orientation(Orientation o) {
        if (orientation_ == o)
            return;
        orientation_ = o;
        request_repaint();
    }
    Orientation orientation() const {
        return orientation_;
    }
 
    // Display options
    void set_show_note_names(bool show) {
        show_names_ = show;
    }
    bool show_note_names() const {
        return show_names_;
    }
 
    void set_highlight_color(Color c) {
        highlight_color_ = c;
    }
 
    void paint(canvas::Canvas& canvas) override;
    void on_mouse_down(Point pos) override;
    void on_mouse_up(Point pos) override;
    void on_mouse_drag(Point pos) override;
    void on_mouse_event(const MouseEvent& event) override;
    bool wants_mouse_input() const override {
        return true;
    }
 
    float intrinsic_height() const override {
        return 80.0f;
    }
 
  private:
    int first_note_ = 36; // C2
    int last_note_ = 96;  // C7
    Orientation orientation_ = Orientation::horizontal;
    bool show_names_ = false;
    // Transparent sentinel (a==0) means "no explicit highlight set" — paint()
    // then falls back to the theme's accent.primary for active keys. A default
    // Color{} is OPAQUE black (a=1), which would make every pressed key render
    // black instead of the accent; keep this explicitly transparent.
    Color highlight_color_{0.0f, 0.0f, 0.0f, 0.0f};
 
    struct NoteState {
        float velocity = 0;
        bool active = false;
    };
    NoteState note_states_[128] = {};
    int mouse_note_ = -1;
 
    bool is_black_key(int note) const;
    int note_at_position(Point pos) const;
    Rect key_rect(int note) const;
    float white_key_width() const;
    int white_key_count() const;
};
 
} // namespace pulp::view