add first version of screen-help

1 files changed, 110 insertions, 0 deletions

diff --git a/lib/nes/app/ui/screen-help.cc b/lib/nes/app/ui/screen-help.cc
new file mode 100644
index 0000000..55d7b86
--- /dev/null
+++ b/lib/nes/app/ui/screen-help.cc
@@ -0,0 +1,110 @@
+#include "nes/app/ui/screen-help.hh"
+#include "nes/app/input/input-manager.hh"
+#include "nes/app/preferences.hh"
+
+namespace
+{
+	
+
+}
+
+namespace nes::app
+{
+	screen_help::screen_help(input_manager& input_manager)
+		: input_manager_{ input_manager }
+	{ }
+
+	auto screen_help::render(renderer& renderer) -> void
+	{
+		renderer.render_fill(color::background_primary);
+		renderer.render_rect(0, 0, 32, 3, color::background_secondary);
+
+		renderer.render_text(
+			2, 1, "Key Bindings", color::foreground_primary,
+			text_attributes{}.set_max_width(26).set_ellipsize_mode(ellipsize_mode::middle));
+
+		auto render_list_item = [&](unsigned& y, string_view name, string_view value, bool fullline = true, bool left = true) -> void
+		{
+			unsigned x_offset = 2;
+			unsigned container_width = renderer::width - 2 * x_offset;
+			if (!fullline)
+			{
+				container_width -= x_offset; // offset between columns
+				container_width /= 2;
+			}
+
+			unsigned column_offset = 0;
+			if (!fullline && !left)
+			{
+				column_offset = container_width + 2 * x_offset;
+			}
+			else
+			{
+				column_offset = x_offset;
+			}
+
+			unsigned max_val_width = (container_width - x_offset) / 2;
+			unsigned value_width = value.get_length();
+			if (value_width > max_val_width)
+			{
+				value_width = max_val_width;
+			}
+
+			unsigned name_width = container_width - value_width - x_offset;
+
+			renderer.render_text(
+				column_offset, y, name, color::foreground_primary,
+				text_attributes{}.set_max_width(name_width).set_ellipsize_mode(ellipsize_mode::middle));
+
+			renderer.render_text(
+				column_offset + container_width, y, value, color::foreground_secondary,
+				text_attributes{}.set_alignment(text_alignment::right).set_max_width(value_width).set_ellipsize_mode(ellipsize_mode::middle));
+			
+			if (fullline || !left)
+			{
+				y += 2;
+			}
+		};
+
+		auto render_title = [&](unsigned& y, string_view title) -> void
+		{
+			renderer.render_text(
+				14 + 2, y, title, color::accent_primary,
+				text_attributes{}.set_alignment(nes::app::text_alignment::center).set_max_width(28).set_ellipsize_mode(ellipsize_mode::middle));
+			y += 2;
+		};
+
+		unsigned y_offset = 5;
+
+		render_title(y_offset, "> Launcher <");
+
+		render_list_item(y_offset, "Select", "<Enter>");
+		render_list_item(y_offset, "Navigation", "<Arrow Keys>");
+		render_list_item(y_offset, "Go Back", "<Backspace>");
+
+		y_offset += 1;
+		render_title(y_offset, "> Games <");
+
+		render_list_item(y_offset, "Up", "W", false, true);
+		render_list_item(y_offset, "Left", "A", false, false);
+		render_list_item(y_offset, "Down", "S", false, true);
+		render_list_item(y_offset, "Right", "D", false, false);
+		render_list_item(y_offset, "Action B", "K", false, true);
+		render_list_item(y_offset, "Action A", "L", false, false);
+		render_list_item(y_offset, "Start", "<Enter>");
+		render_list_item(y_offset, "Select", "<Space>");
+	}
+
+	auto screen_help::process_events() -> action
+	{
+		while (auto const event = input_manager_.get_keyboard().poll_event())
+		{
+			if (event == input_event::key_down(key::backspace))
+			{
+				return action::go_to_title();
+			}
+		}
+
+		return action{};
+	}
+} // namespace nes::app
\ No newline at end of file