#include <stdio.h>
#include <windows.h>
#include <math.h>
#include <time.h>
#include <unistd.h>

typedef struct LinkedMem {

    UINT32  uiVersion;
    DWORD   uiTick;


    float   fAvatarPosition[3];
    float   fAvatarFront[3];
    float   fAvatarTop[3];

    wchar_t name[256];

    float   fCameraPosition[3];
    float   fCameraFront[3];
    float   fCameraTop[3];
    wchar_t identity[256];


    UINT32  context_len;

    unsigned char context[256];
    wchar_t description[2048];
} LinkedMem;

LinkedMem *lm = NULL;


void ErrorExit(LPTSTR lpszFunction)
{
    // Retrieve the system error message for the last-error code

    LPVOID lpMsgBuf;
    DWORD dw = GetLastError();

    FormatMessage(
        FORMAT_MESSAGE_ALLOCATE_BUFFER |
        FORMAT_MESSAGE_FROM_SYSTEM |
        FORMAT_MESSAGE_IGNORE_INSERTS,
        NULL,
        dw,
        MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
        (LPTSTR) &lpMsgBuf,
        0, NULL );

    // Display the error message and exit the process

    printf(TEXT("%s failed with error %d: %s"),
        lpszFunction, dw, lpMsgBuf);

    LocalFree(lpMsgBuf);
}

int main(void) {

    HANDLE hMapObject = OpenFileMappingW(FILE_MAP_ALL_ACCESS, FALSE, L"MumbleLink");
    float slots[2][3] = {{0.0f, 0.0f, 0.0f}, {0.0f, 0.0f, 0.0f}};
    int slot = 0;
    float distance = 0;
    float speed;
    time_t stamps[2];

    if (hMapObject == NULL) {
        ErrorExit( "unable to open mapping\n" );

        return 0;
    }
    lm = (LinkedMem *) MapViewOfFile(hMapObject, FILE_MAP_ALL_ACCESS, 0, 0, sizeof(LinkedMem));

    if (lm == NULL) {
        ErrorExit( "unable to map view\n" );
        CloseHandle(hMapObject);
        hMapObject = NULL;
        return 0;
    }

    while(1) {
        slots[slot][0] = lm->fAvatarPosition[0];
        slots[slot][1] = lm->fAvatarPosition[1];
        slots[slot][2] = lm->fAvatarPosition[2];
        stamps[slot] = time( NULL );
        distance = sqrtf(
            powf( slots[1][0] - slots[0][0], 2)
            + powf( slots[1][1] - slots[0][1], 2)
            + powf( slots[1][2] - slots[0][2], 2)
            ) * 39.370078740157f;

        speed = distance / fabsf( difftime( stamps[0], stamps[1] ) );
        /*printf( "timediff: %f\n", fabsf(difftime( stamps[0], stamps[1] ) ));*/

        if( speed > 0 ) {
            printf( "speed: %f\n", speed );
        }

        slot++;
        slot %= 2;
        sleep( 1 );
    }
    return 0;
}