/* copyright Constantin Fürst 2021, licensed under GPLv3, a copy is provided in LICENSE */
/* non-major portions of the code were taken from DWM (https://dwm.suckless.org) */
/* inspired and named after keym by Chris Willcocks (https://github.com/cwkx/keym) */

#include <stdio.h>
#include <unistd.h>
#include <stdint.h>
#include <inttypes.h>

#include <X11/Xlib.h>

#include "config.h"
#include "typedefs.h"

keym_state state;

void eventhandler(XEvent *e) {
    uint32_t arg;
    KeySym keysym;
    XKeyEvent *ev;

    ev = &e->xkey;
    keysym = XKeycodeToKeysym(state.display, (KeyCode)ev->keycode, 0);

    for (uint32_t i = 0; i < LENGTH(keys); i++) {
        if (
            keysym == keys[i].keysym &&
            CLEANMASK(keys[i].mod) == CLEANMASK(ev->state) &&
            keys[i].func
            )
        {
            arg = keys[i].arg;

            switch (ev->type) {
                case KeyRelease:
                    arg |= KEY_RELEASE_MASK;
                    break;
                case KeyPress:
                default: break;
            }

            keys[i].func(&arg);
        }
    }
}

void grabkeys() {
    KeyCode code;

    XUngrabKey(state.display, AnyKey, AnyModifier, state.window);

    for (uint32_t i = 0; i < LENGTH(keys); i++) {
        if ((code = XKeysymToKeycode(state.display, keys[i].keysym))) {
            XGrabKey(state.display, code, keys[i].mod, state.window, True, GrabModeAsync, GrabModeAsync);
        }
    }
}

int setup() {
    state.speed = 1;
    state.quit = False;

    if (!(state.display = XOpenDisplay(NULL))) {
        fprintf(stderr, "[x] error opening display\n");
        return 1;
    }

    state.window = XDefaultRootWindow(state.display);
    state.screen = DefaultScreen(state.display);

    XSelectInput(state.display, state.window, ExposureMask | KeyPressMask);
    XMapWindow(state.display, state.window);

    state.x11_fd = ConnectionNumber(state.display);;

    grabkeys();

    return 0;
}

void cleanup() {
    XUngrabKey(state.display, AnyKey, AnyModifier, state.window);
    FD_CLR(state.x11_fd, &state.in_fds);
    XUnmapWindow(state.display,state.window);
    XCloseDisplay(state.display);
}

void set_x_update(uint32_t tv_usec) {
    FD_ZERO(&state.in_fds);
    FD_SET(state.x11_fd, &state.in_fds);

    struct timeval tv;
    tv.tv_sec = 0;
    tv.tv_usec = tv_usec;

    select(state.x11_fd + 1, &state.in_fds, NULL, NULL, &tv);
}

void move_pointer_by_state() {
    XWarpPointer(state.display, None, None, 0, 0, 0, 0, state.x, state.y);
}

int main() {
    XEvent ev;

    if (setup() != 0) return -1;
    XSync(state.display, False);

    while (!state.quit) {
        while (XPending(state.display))
            XNextEvent(state.display, &ev);

        set_x_update(speeds[state.speed]);
        eventhandler(&ev);

        move_pointer_by_state();
    }

    cleanup();
    return 1;
}