LibWeb: Add a blinking text cursor :^)

Each Web::Frame now has a cursor that sits at a DOM::Position. It will
blink and look like a nice regular text cursor.

It doesn't really do anything yet, but it will eventually.

2 files changed, 24 insertions, 0 deletions

diff --git a/Libraries/LibWeb/Layout/LayoutText.cpp b/Libraries/LibWeb/Layout/LayoutText.cpp
index 7a4cc81885..55696b5531 100644
--- a/Libraries/LibWeb/Layout/LayoutText.cpp
+++ b/Libraries/LibWeb/Layout/LayoutText.cpp
@@ -32,6 +32,7 @@
 #include <LibWeb/DOM/Document.h>
 #include <LibWeb/Layout/LayoutBlock.h>
 #include <LibWeb/Layout/LayoutText.h>
+#include <LibWeb/Page/Frame.h>
 #include <ctype.h>
 
 namespace Web {
@@ -101,6 +102,28 @@ void LayoutText::paint_fragment(PaintContext& context, const LineBoxFragment& fr
         painter.add_clip_rect(enclosing_int_rect(selection_rect));
         painter.draw_text(enclosing_int_rect(fragment.absolute_rect()), text.substring_view(fragment.start(), fragment.length()), Gfx::TextAlignment::TopLeft, context.palette().selection_text());
     }
+
+    paint_cursor_if_needed(context, fragment);
+}
+
+void LayoutText::paint_cursor_if_needed(PaintContext& context, const LineBoxFragment& fragment) const
+{
+    if (!frame().cursor_blink_state())
+        return;
+
+    if (frame().cursor_position().node() != &node())
+        return;
+
+    if (!(frame().cursor_position().offset() >= (unsigned)fragment.start() && frame().cursor_position().offset() < (unsigned)(fragment.start() + fragment.length())))
+        return;
+
+    auto fragment_rect = fragment.absolute_rect();
+
+    float cursor_x = fragment_rect.x() + specified_style().font().width(fragment.text().substring_view(0, frame().cursor_position().offset() - fragment.start()));
+    float cursor_top = fragment_rect.top();
+    float cursor_height = fragment_rect.height();
+    Gfx::IntRect cursor_rect(cursor_x, cursor_top, 1, cursor_height);
+    context.painter().draw_rect(cursor_rect, context.palette().text_cursor());
 }
 
 template<typename Callback>
diff --git a/Libraries/LibWeb/Layout/LayoutText.h b/Libraries/LibWeb/Layout/LayoutText.h
index 66b3bf0cad..155694c25a 100644
--- a/Libraries/LibWeb/Layout/LayoutText.h
+++ b/Libraries/LibWeb/Layout/LayoutText.h
@@ -54,6 +54,7 @@ public:
 
 private:
     void split_into_lines_by_rules(LayoutBlock& container, LayoutMode, bool do_collapse, bool do_wrap_lines, bool do_wrap_breaks);
+    void paint_cursor_if_needed(PaintContext&, const LineBoxFragment&) const;
 
     template<typename Callback>
     void for_each_chunk(Callback, LayoutMode, bool do_wrap_lines, bool do_wrap_breaks) const;