1 files changed, 47 insertions, 0 deletions
diff --git a/arch/x86_64/src/video/vga/text.cpp b/arch/x86_64/src/video/vga/text.cpp
new file mode 100644
index 0000000..f1e7412
--- /dev/null
+++ b/arch/x86_64/src/video/vga/text.cpp
@@ -0,0 +1,47 @@
+#include "arch/video/vga/text.hpp"
+
+#include "arch/boot/pointers.hpp"
+#include "arch/video/vga/io.hpp"
+#include "memory/asm_pointer.hpp"
+
+#include <algorithm>
+#include <string_view>
+#include <utility>
+
+namespace teachos::arch::video::vga::text
+{
+
+  namespace
+  {
+    auto constexpr default_text_buffer_address = 0xb8000;
+
+    extern "C" std::pair<char, attribute> * vga_buffer_pointer;
+    auto constinit text_buffer = teachos::memory::asm_pointer{vga_buffer_pointer};
+
+    auto write(char code_point, attribute attribute) -> void
+    {
+      auto & p = *text_buffer;
+      (*p++) = std::pair{code_point, attribute};
+    };
+  }  // namespace
+
+  auto clear(attribute attribute) -> void
+  {
+    *text_buffer = reinterpret_cast<decltype(text_buffer)::pointer>(default_text_buffer_address);
+    std::ranges::fill_n(*text_buffer, 2000, std::pair{' ', attribute});
+  }
+
+  auto cursor(bool enabled) -> void
+  {
+    auto cursor_disable_byte = std::byte{!enabled} << 5;
+
+    crtc::address_port::write(crtc::registers::cursor_start);
+    crtc::data_port::write(vga::crtc::data_port::read() | cursor_disable_byte);
+  }
+
+  auto write(std::string_view code_points, attribute attribute) -> void
+  {
+    std::ranges::for_each(code_points, [&](auto code_point) { write(code_point, attribute); });
+  }
+
+}  // namespace teachos::arch::video::vga::text