/**
 * Platform compatibility layer for POSIX functions on Windows
 */

#ifndef PLATFORM_COMPAT_H
#define PLATFORM_COMPAT_H

#ifdef _WIN32
    #include <winsock2.h>
    #include <ws2tcpip.h>
    #include <windows.h>
    #include <io.h>
    #include <time.h>
    #include <fcntl.h>
    #include <stdint.h>
    
    // POSIX functions missing on Windows
    #define strcasecmp _stricmp
    #define strncasecmp _strnicmp
    
    // poll() and pollfd are already defined in winsock2.h on MSYS2 UCRT64
    // Only define if not already present
    #ifndef POLLIN
        #define POLLIN 0x0001
    #endif
    #ifndef POLLOUT
        #define POLLOUT 0x0004
    #endif
    #ifndef POLLERR
        #define POLLERR 0x0008
    #endif
    #ifndef POLLHUP
        #define POLLHUP 0x0010
    #endif
    #ifndef POLLNVAL
        #define POLLNVAL 0x0020
    #endif
    #ifndef POLLPRI
        #define POLLPRI 0x0002
    #endif
    
    // gettimeofday for Windows (timezone already defined in time.h)
    #ifndef HAVE_GETTIMEOFDAY
    static inline int gettimeofday(struct timeval *tv, void *tz) {
        (void)tz;
        if (tv) {
            FILETIME ft;
            ULARGE_INTEGER ull;
            GetSystemTimeAsFileTime(&ft);
            ull.LowPart = ft.dwLowDateTime;
            ull.HighPart = ft.dwHighDateTime;
            // Convert from 100-nanosecond intervals since 1601 to Unix epoch
            tv->tv_sec = (long)(ull.QuadPart / 10000000ULL - 11644473600ULL);
            tv->tv_usec = (long)((ull.QuadPart % 10000000ULL) / 10);
        }
        return 0;
    }
    #endif
    
    // Pipe creation for Windows
    static inline int platform_pipe(int pipefd[2]) {
        return _pipe(pipefd, 4096, _O_BINARY);
    }
    #define pipe platform_pipe
    
    // nfds_t already defined in winsock2.h on MSYS2
    
    // fcntl replacement for Windows (simplified - only supports F_GETFL/F_SETFL with O_NONBLOCK)
    #ifndef F_GETFL
        #define F_GETFL 3
    #endif
    #ifndef F_SETFL
        #define F_SETFL 4
    #endif
    #ifndef O_NONBLOCK
        #define O_NONBLOCK 0x4000
    #endif
    
    static inline int platform_fcntl(int fd, int cmd, ... /* arg */ ) {
        va_list ap;
        va_start(ap, cmd);
        
        if (cmd == F_GETFL) {
            va_end(ap);
            // Return current flags (always 0 on Windows, can't query easily)
            return 0;
        } else if (cmd == F_SETFL) {
            int flags = va_arg(ap, int);
            va_end(ap);
            if (flags & O_NONBLOCK) {
                // Set non-blocking mode
                u_long mode = 1;
                return ioctlsocket(fd, FIONBIO, &mode);
            }
            return 0;
        }
        
        va_end(ap);
        errno = EINVAL;
        return -1;
    }
    #define fcntl platform_fcntl
    
    // nanosleep already defined in pthread_time.h on MSYS2
    // poll() and pollfd already defined in winsock2.h on MSYS2
    // Use WSAPoll on Windows (available in Vista and later)
    #define poll WSAPoll
    
    // sa_family_t might not be defined on some Windows setups
    #ifndef sa_family_t
        typedef unsigned short sa_family_t;
    #endif
    
#else
    // POSIX - include standard headers
    #include <sys/time.h>
    #include <strings.h>
    #include <arpa/inet.h>
    #include <netinet/in.h>
    #include <fcntl.h>
    #include <unistd.h>
    #include <poll.h>
#endif

#endif // PLATFORM_COMPAT_H