// Copyright (C) 2022 RozK
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program 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 Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

#include "../events.hpp"
#include <X11/Xlib.h>

extern Display * rk_display;
extern Window rk_window;
extern XIC rk_input_context;

unsigned rk_events_mask = KeyPressMask | KeyReleaseMask;

rk_uint rk_consume_events(
    rk_event * events,
    rk_uint max_events) {
    if (!events || !max_events) {
        return 0;
    }
    XEvent x11_event;
    unsigned nevents = 0;
    wchar_t string[256];
    KeySym keysym;
    Status status;
    while (nevents < max_events && XCheckWindowEvent(rk_display, rk_window, rk_events_mask, &x11_event)) {
        if (XFilterEvent(&x11_event, 0)) {
            continue;
        }
        rk_event & event = events[nevents++];
        switch (x11_event.type) {
            case KeyPress:
                event.type = RK_EVENT_KEY_PRESS;
                event.key.code = x11_event.xkey.keycode;
                XwcLookupString(rk_input_context, &x11_event.xkey, string, 256, &keysym, &status);
                switch (status) {
                    case XLookupChars:
                        event.key.symbol = XLookupKeysym(&x11_event.xkey, 0);
                        event.key.character = string[0];
                        break;
                    case XLookupKeySym:
                        event.key.symbol = keysym;
                        event.key.character = 0;
                        break;
                    case XLookupBoth:
                        event.key.symbol = keysym;
                        event.key.character = string[0];
                        break;
                    default:
                        event.key.symbol = 0;
                        event.key.character = 0;
                        break;
                }
                break;
            case KeyRelease:
                event.type = RK_EVENT_KEY_RELEASE;
                event.key.code = x11_event.xkey.keycode;
                event.key.symbol = XLookupKeysym(&x11_event.xkey, 0);
                event.key.character = 0;
                break;
        }
    }
    return nevents;
}

void rk_flush_events() {
    XEvent x11_event;
    while (XCheckWindowEvent(rk_display, rk_window, rk_events_mask, &x11_event)) {
    }
}