// libcursed -- C++ classes for dealing with curses
// Copyright (C) 2019 xaizek <xaizek@posteo.net>
//
// This file is part of libcursed.
//
// libcursed is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// libcursed is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with libcursed.  If not, see <https://www.gnu.org/licenses/>.

#include "Input.hpp"

#include <curses.h>

#include <stdexcept>

#include "guts/Window.hpp"

using namespace cursed;

InputElement::InputElement(int status, std::wint_t code)
    : status(status), code(code)
{ }

bool
InputElement::isEndOfInput() const
{
    return (status == ERR);
}

bool
InputElement::isTerminalResize() const
{
    return (status == KEY_CODE_YES && code == KEY_RESIZE);
}

InputElement::operator wchar_t() const
{
    return (status == OK ? code : L'\0');
}

bool
InputElement::isFunctionalKey() const
{
    return (status == KEY_CODE_YES);
}

bool
InputElement::operator==(wchar_t wch) const
{
    return (status == OK && static_cast<wchar_t>(*this) == wch);
}

Input::Input(Keypad keypad)
{
#if defined(NCURSES_EXT_FUNCS) && NCURSES_EXT_FUNCS >= 20081102
    // Use ncurses specific function to make delay after pressing escape key
    // unnoticeable.  Can be zero, but in some corner cases multiple bytes
    // composing a functional key code might be handled to the application with
    // a delay, so small delay is safer.
    set_escdelay(5);
#endif

    guts::keypad(readWin, keypad == Keypad::Enabled);
    wtimeout(peekWin, 0);

    // `man wget_wch`:
    //   If the window is not a pad and has been moved or modified since the
    //   last call to wrefresh, wrefresh will be called before another character
    //   is read.
    wnoutrefresh(readWin);
    wnoutrefresh(peekWin);
}

InputElement
Input::read()
{
    std::wint_t wch;
    int status = wget_wch(readWin, &wch);

    InputElement ie(status, wch);

    if (ie.isTerminalResize()) {
        // Prompt curses to resize `stdscr`.
        refresh();
    }

    return ie;
}

InputElement
Input::peek()
{
    std::wint_t wch;
    int status = wget_wch(peekWin, &wch);
    InputElement ie(status, wch);

    if (!ie.isEndOfInput() && unget_wch(ie.code) == ERR) {
        // In practice this shouldn't happen.  If unget buffer was full, we read
        // from it and just return back to it.
        throw std::runtime_error("Can't unget input element after peek");
    }
    return ie;
}