#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <linux/input.h>
#include <linux/uinput.h>
#include <stdint.h>
#include <time.h>

#define release    0
#define press      1
#define autorepeat 2


struct uinput_user_dev  ui_dev;
struct input_event      ui_ev;
int                     ui_fd, i;

inline int open_uinput();
inline int send_event(uint16_t type, uint16_t code, int32_t value);
inline int send_report();
inline int send_rel_mouse(int32_t x, int32_t y);
inline int send_abs_mouse(int32_t x, int32_t y);

#define send_key_macro(x) \
    inline int send_key_##x(uint16_t key) {  \
        return send_event(EV_KEY, key, x);   \
    }


send_key_macro(press);
send_key_macro(release);
send_key_macro(autorepeat);


int main(int argc, char *argv[])
{

    if(open_uinput() < 0)
    {
        printf("Unable to open uinput.\n");
        return -1;
    }

    usleep(100);

    memset(&ui_ev,  0, sizeof(ui_ev));
    memset(&ui_dev, 0, sizeof(ui_dev));

    strncpy(ui_dev.name, "uinput-test", UINPUT_MAX_NAME_SIZE);
    ui_dev.id.bustype = BUS_VIRTUAL;
    ui_dev.id.vendor  = 0x1234;
    ui_dev.id.product = 0xABCD;
    ui_dev.id.version = 1;

    ui_dev.absmin[ABS_X] = 0;
    ui_dev.absmax[ABS_X] = 1023;
    ui_dev.absmin[ABS_Y] = 0;
    ui_dev.absmax[ABS_Y] = 1023;

    ioctl(ui_fd, UI_SET_EVBIT,  EV_KEY);
    ioctl(ui_fd, UI_SET_EVBIT,  EV_REP);

    for(i = 0; i < KEY_MAX; i++)
    {
        ioctl(ui_fd, UI_SET_KEYBIT, i);
    }

    ioctl(ui_fd, UI_SET_EVBIT, EV_REL);
    ioctl(ui_fd, UI_SET_EVBIT, EV_ABS);
    ioctl(ui_fd, UI_SET_RELBIT, REL_X);
    ioctl(ui_fd, UI_SET_RELBIT, REL_Y);

    write(ui_fd, &ui_dev, sizeof(ui_dev));
    ioctl(ui_fd, UI_DEV_CREATE);

    usleep(100);

    while(1)
    {
        send_key_press(KEY_A);
        send_key_release(KEY_A);
        send_rel_mouse(110, 110);
        send_report();
        usleep(500 * 1000);
    }

    ioctl(ui_fd, UI_DEV_DESTROY);
    close(ui_fd);
    printf("\nExit.\n\n");
    return 0;
}

int open_uinput()
{
    if((ui_fd = open("/dev/uinput", O_WRONLY | O_NONBLOCK)) < 0)
    {
        if((ui_fd = open("/dev/input/uinput", O_WRONLY | O_NONBLOCK)) >= 0)
        {
            return 1;
        }
        return -1;
    }
    return 1;
}

int send_event(uint16_t type, uint16_t code, int32_t value)
{
    gettimeofday(&ui_ev.time, NULL);
    ui_ev.type = type;
    ui_ev.code = code;
    ui_ev.value = value;
    return write(ui_fd, &ui_ev, sizeof(ui_ev));
}

int send_report()
{
    return send_event(EV_SYN, SYN_REPORT, 0);
}

int send_rel_mouse(int32_t x, int32_t y)
{
    int ret;
    ret =  send_event(EV_REL, REL_X, x);
    ret += send_event(EV_REL, REL_Y, y);
    return ret;
}

int send_abs_mouse(int32_t x, int32_t y)
{
    int ret;
    ret =  send_event(EV_ABS, ABS_X, x);
    ret += send_event(EV_ABS, ABS_Y, y);
    return ret;
}