notcurses/include/ncpp/Reader.hh

#ifndef __NCPP_READER_HH
#define __NCPP_READER_HH

#include <notcurses/notcurses.h>

#include "NCAlign.hh"
#include "Plane.hh"
#include "Utilities.hh"
#include "Widget.hh"

namespace ncpp
{
	class NCPP_API_EXPORT Reader : public Widget
	{
	public:
		explicit Reader (Plane *plane, const ncreader_options *opts)
			: Widget (Utilities::get_notcurses_cpp (plane))
		{
			ensure_valid_plane (plane);
			common_init (Utilities::to_ncplane (plane), opts);
			take_plane_ownership (plane);
		}

		explicit Reader (Plane &plane, const ncreader_options *opts)
			: Widget (Utilities::get_notcurses_cpp (plane))
		{
			ensure_valid_plane (plane);
			common_init (Utilities::to_ncplane (plane), opts);
			take_plane_ownership (plane);
		}

		~Reader ()
		{
			if (!is_notcurses_stopped ())
				ncreader_destroy (reader, nullptr);
		}

		bool clear () const NOEXCEPT_MAYBE
		{
			bool ret = ncreader_clear (reader) != 0;
			return error_guard_cond<bool, bool> (ret, ret);
		}

		//
		// None of the move* methods should throw since their return value (0 - moved, -1 - not moved) appear to be
		// purely informational, not errors per se. If we had `can_move*` functions then `move*` could throw exceptions,
		// potentially.
		//
		int move_left () const noexcept
		{
			return ncreader_move_left (reader);
		}

		int move_right () const noexcept
		{
			return ncreader_move_right (reader);
		}

		int move_up () const noexcept
		{
			return ncreader_move_up (reader);
		}

		int move_down () const noexcept
		{
			return ncreader_move_down (reader);
		}

		bool write_egc (const char *egc) const NOEXCEPT_MAYBE
		{
			return error_guard (ncreader_write_egc (reader, egc), -1);
		}

		char* get_contents () const noexcept
		{
			return ncreader_contents(reader);
		}

		Plane* get_plane () const noexcept
		{
			return Plane::map_plane (ncreader_plane (reader));
		}

	private:
		void common_init (ncplane *n, const ncreader_options *opts)
		{
			reader = ncreader_create (n, opts);
			if (reader == nullptr)
				throw init_error ("Notcurses failed to create a new reader");
		}

	private:
		ncreader *reader;
	};
}
#endif