#define __KAVSOCKETS_C

#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <sys/un.h>
#include <arpa/inet.h>
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <limits.h>
#include <errno.h>

#include "kaverrors.h"
#include "kavsockets.h"


int kavSocketConnect(const char *sock, int * const sockFamily)
{
    int ret = -1;
    char *address = 0;
    int port = 0;

    // parse destination stirng
    if ((port = parseDestination(sock, &address)) == -1)
    {
        kavSetError("Wrong destination parameter");
        return (-1);
    }

    // connect to kavmd
    if (port == 0)
    {
        *sockFamily = KAV_SOCK_UNIX;
        ret = kavSocketConnectUnix(address);
    }
    else
    {
        *sockFamily = KAV_SOCK_INET;
        ret = kavSocketConnectInet(address, port);
    }

    return (ret);
}


void kavSocketClose(int fd)
{
    close(fd);
}


int kavSocketWrite(int fd, const void *buf, unsigned int size)
{
    int ret, total = 0;

    do
    {
        ret = write(fd, buf + total, size - total);
        if (ret > 0)
            total += ret;
    } while ((ret == -1 && errno == EINTR)
            || (total < size));

    if (ret == -1)
        kavSetError(strerror(errno));

    return (ret == -1 ? -1 : total);
}


int kavSocketRead(int fd, void *buf, unsigned int size)
{
    int ret, total = 0;

    do
    {
        ret = read(fd, buf + total, size - total);
        if (ret > 0)
            total += ret;
    } while ((ret == -1 && errno == EINTR)
            || (total < size));

    if (ret == -1)
        kavSetError(strerror(errno));

    return (ret == -1 ? -1 : total);
}


static int kavSocketConnectInet(const char *dest, unsigned short port)
{
    struct sockaddr_in sa;
    int s = socket(AF_INET, SOCK_STREAM, 0);

    if (s == -1)
    {
        kavSetError(strerror(errno));
        return (-1);
    }

    memset(&sa, 0, sizeof(struct sockaddr_in));
    sa.sin_addr.s_addr = inet_addr(dest);

    if (sa.sin_addr.s_addr == INADDR_NONE)
    {
        kavSetError(strerror(errno));
        return (-1);
    }

    sa.sin_port = htons(port);
    sa.sin_family = AF_INET;

    if (connect(s, (const struct sockaddr *) &sa, sizeof(struct sockaddr_in)) == -1)
    {
        kavSetError(strerror(errno));
        close(s);
        return (-1);
    }

    return (s);
}


static int kavSocketConnectUnix(const char *dest)
{
    struct sockaddr_un sa;
    int s;
    
    // buffer overflow is bad, mmk ?
    if (strlen(dest) >= sizeof(sa.sun_path))
    {
        char tmp[512];
        snprintf((char *) &tmp, sizeof(tmp),
                "Path too long (must be less or equal to %lu)",
                sizeof(sa.sun_path));
        kavSetError(tmp);

        return (-1);
    }
    
    if ((s = socket(AF_UNIX, SOCK_STREAM, 0)) == -1)
    {
        kavSetError(strerror(errno));
        return (-1);
    }

    memset(&sa, 0, sizeof(struct sockaddr_un));
    sa.sun_family = AF_UNIX;
    strcpy(sa.sun_path, dest);

    if (connect(s, (const struct sockaddr *) &sa, SUN_LEN(&sa)) == -1)
    {
        kavSetError(strerror(errno));
        close(s);
        return (-1);
    }

    return (s);
}


static int parseDestination(const char *dest, char **address)
{
    if (strstr(dest, "local:") == dest)
    {
        *address = strchr(dest, ':') + 1;

        if (**address == '\0')
            return (-1);

        return (0); // 0 means that the socket is of type UNIX/LOCAL
    }
    else if (strstr(dest, "inet:") == dest)
    {
        int port = 0;
        char *pos1, *pos2 = (char *) dest + 4; // 4 = strlen("inet")
        char *endptr;

        if ((pos1 = strchr(dest, '@')) == 0)
            return (-1);

        // don't modify the received string, work on a copy
        if ((*address = malloc(pos1 - pos2)) == 0)
            return (-1);

        strncpy(*address, pos2 + 1, pos1 - pos2 - 1);
        address[pos1 - pos2 - 1] = 0;
        port = strtol(*address, &endptr, 10);
        free(*address);

        if (*endptr != '\0' || port < 0 || port > USHRT_MAX)
            return (-1);

        *address = pos1 + 1;
        if (strlen(*address) == 0)
            return (-1);

        return (port);
    }

    return (-1);
}