/**
 * @brief `ncurses` window displaying contents of a pseudo terminal
 * @author Christian Burger (christian@krikkel.de)
 */

#include "SingleUserInput.hpp"

#include <cursesw.h>
#include <pty.h>
#include <vterm.h>
#include <string>
#include <thread>
#include <mutex>

#ifdef add_wch
inline void UNDEF(add_wch)(const cchar_t *character) { add_wch(character); }
#undef add_wch
#define add_wch UNDEF(add_wch)
#endif

#ifdef get_wch
inline void UNDEF(get_wch)(wint_t *character) { get_wch(character); }
#undef get_wch
#define get_wch UNDEF(get_wch)
#endif

namespace krikkel::NCursesPtyWindow
{
    class Window : public NCursesWindow
    {
        public:
            Window(int lines, int columns, int y, int x);
            ~Window();

            int getFdPtyClient() const;
            void writeToClient(const char * string, size_t length);
            void writeUnicodeCharToClient(wint_t character);
            void writeKeyToClient(VTermKey key);

            SingleUserInput readSingleUserInput();

            int add_wch(const cchar_t *character);
            int get_wch(wint_t *character);
            int refresh() override;
            int wresize(int rows, int cols);

        private:
            int fdPtyHost, fdPtyClient;
            struct termios terminalParameters;
            VTerm *pseudoTerminal;
            std::mutex writeToPseudoTerminalMutex;
            VTermScreen *pseudoTerminalScreen;
            static VTermScreenCallbacks screenCallbacks;
            /// @todo one line is at most 4096 chars long
            static const uint16_t PTY_CLIENT_OUTPUT_BUFFER_SIZE = 2 * 4096;
            char ptyClientOutputBuffer[PTY_CLIENT_OUTPUT_BUFFER_SIZE];
            uint16_t cursorX, cursorY;

            std::thread readPtyClientThread;
            void readFromPtyClientThreadMethod();
            void readFromPtyClient();

            int handlerDamage(VTermRect rect);
            int handlerMoveRect(VTermRect dest, VTermRect src);
            int handlerMoveCursor(VTermPos pos, VTermPos oldpos, int visible);
            int handlerSetTermProp(VTermProp prop, VTermValue *val);
            int handlerBell();
            int handlerResize(int rows, int cols);
            int handlerPushLine(int cols, const VTermScreenCell *cells);
            int handlerPopLine(int cols, VTermScreenCell *cells);

            attr_t extractAttributesFromVTermCell(VTermScreenCell cell);
            short extractColorFromVTermCell(VTermScreenCell cell);
            void copyPtyCellToNCursesWindow(int x, int y);

            static int staticHandlerDamage(VTermRect rect, void *user);
            static int staticHandlerMoveRect(VTermRect dest, VTermRect src, void *user);
            static int staticHandlerMoveCursor(VTermPos pos, VTermPos oldpos, int visible, void *user);
            static int staticHandlerSetTermProp(VTermProp prop, VTermValue *val, void *user);
            static int staticHandlerBell(void *user);
            static int staticHandlerResize(int rows, int cols, void *user);
            static int staticHandlerPushLine(int cols, const VTermScreenCell *cells, void *user);
            static int staticHandlerPopLine(int cols, VTermScreenCell *cells, void *user);
            static void staticHandlerOutput(const char *s, size_t len, void *user);
    };
}