1 files changed, 83 insertions, 0 deletions
diff --git a/Libraries/LibGUI/GTextDocument.h b/Libraries/LibGUI/GTextDocument.h
new file mode 100644
index 0000000000..b1bd94246d
--- /dev/null
+++ b/Libraries/LibGUI/GTextDocument.h
@@ -0,0 +1,83 @@
+#pragma once
+
+#include <AK/NonnullOwnPtrVector.h>
+#include <AK/NonnullRefPtr.h>
+#include <AK/RefCounted.h>
+#include <LibDraw/Color.h>
+#include <LibDraw/Font.h>
+#include <LibGUI/GTextRange.h>
+
+class GTextEditor;
+class GTextDocumentLine;
+
+struct GTextDocumentSpan {
+    GTextRange range;
+    Color color;
+    const Font* font { nullptr };
+};
+
+class GTextDocument : public RefCounted<GTextDocument> {
+public:
+    static NonnullRefPtr<GTextDocument> create(GTextEditor& editor)
+    {
+        return adopt(*new GTextDocument(editor));
+    }
+
+    int line_count() const { return m_lines.size(); }
+    const GTextDocumentLine& line(int line_index) const { return m_lines[line_index]; }
+    GTextDocumentLine& line(int line_index) { return m_lines[line_index]; }
+
+    void set_spans(const Vector<GTextDocumentSpan>& spans) { m_spans = spans; }
+
+    void set_text(const StringView&);
+
+    const NonnullOwnPtrVector<GTextDocumentLine>& lines() const { return m_lines; }
+    NonnullOwnPtrVector<GTextDocumentLine>& lines() { return m_lines; }
+
+    bool has_spans() const { return !m_spans.is_empty(); }
+    const Vector<GTextDocumentSpan>& spans() const { return m_spans; }
+
+private:
+    explicit GTextDocument(GTextEditor&);
+
+    NonnullOwnPtrVector<GTextDocumentLine> m_lines;
+    Vector<GTextDocumentSpan> m_spans;
+
+    GTextEditor& m_editor;
+};
+
+class GTextDocumentLine {
+    friend class GTextEditor;
+    friend class GTextDocument;
+
+public:
+    explicit GTextDocumentLine(GTextEditor&);
+    GTextDocumentLine(GTextEditor&, const StringView&);
+
+    StringView view() const { return { characters(), length() }; }
+    const char* characters() const { return m_text.data(); }
+    int length() const { return m_text.size() - 1; }
+    void set_text(const StringView&);
+    void append(char);
+    void prepend(char);
+    void insert(int index, char);
+    void remove(int index);
+    void append(const char*, int);
+    void truncate(int length);
+    void clear();
+    void recompute_visual_lines();
+    int visual_line_containing(int column) const;
+    int first_non_whitespace_column() const;
+
+    template<typename Callback>
+    void for_each_visual_line(Callback) const;
+
+private:
+    GTextEditor& m_editor;
+
+    // NOTE: This vector is null terminated.
+    Vector<char> m_text;
+
+    Vector<int, 1> m_visual_line_breaks;
+    Rect m_visual_rect;
+};