#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>

#include <patty/ax25.h>

static patty_ax25_if *create_tnc(const char *device) {
    patty_ax25_if *iface;

    static char * prefix = "kiss";
    static int    number = 0;

    if ((iface = malloc(sizeof(*iface))) == NULL) {
        goto error_malloc_iface;
    }

    memset(iface, '\0', sizeof(*iface));

    if ((iface->tnc = patty_kiss_tnc_open(device)) == NULL) {
        goto error_kiss_tnc_open;
    }

    iface->type = PATTY_AX25_IF_KISS_TNC_TTY;

    snprintf(iface->name, sizeof(iface->name), "%s%d", prefix, number++);

    return iface;

error_kiss_tnc_open:
    free(iface);

error_malloc_iface:
    return NULL;
}

static void destroy_tnc(patty_ax25_if *iface) {
    patty_kiss_tnc_close(iface->tnc);
}

patty_ax25_if *patty_ax25_if_create(int opts, void *info) {
    patty_ax25_if *iface;

    switch (PATTY_AX25_IF_OPT_TYPE(opts)) {
        case PATTY_AX25_IF_KISS_TNC_TTY: {
            iface = create_tnc((const char *)info);
            
            break;
        }

        default: {
            errno = EINVAL;

            goto error;
        }
    }

    if (iface == NULL) {
        goto error;
    }

    if ((iface->addresses = patty_list_new()) == NULL) {
        goto error;
    }

    return iface;

error:
    return NULL;
}

void patty_ax25_if_destroy(patty_ax25_if *iface) {
    switch (iface->type) {
        case PATTY_AX25_IF_KISS_TNC_TTY: {
            destroy_tnc(iface); break;
        }

        default: break;
    }
}

int patty_ax25_if_each_address(patty_ax25_if *iface, int (*callback)(patty_ax25_address *, void *), void *ctx) {
    patty_list_iterator *iter;
    patty_ax25_address *address;

    if ((iter = patty_list_start(iface->addresses)) == NULL) {
        goto error_list_start;
    }

    while ((address = patty_list_next(iter)) != NULL) {
        if (callback(address, ctx) < 0) {
            goto error_callback;
        }
    }

    patty_list_finish(iter);

    return 0;

error_callback:
    patty_list_finish(iter);

error_list_start:
    return -1;
}

static patty_ax25_address *find_address(patty_ax25_if *iface, const char *callsign, int ssid) {
    patty_list_iterator *iter;
    patty_ax25_address *address;

    if ((iter = patty_list_start(iface->addresses)) == NULL) {
        goto error_list_start;
    }

    while ((address = patty_list_next(iter)) != NULL) {
        if (strncmp(address->callsign, callsign, sizeof(address->callsign)) != 0) {
            continue;
        }

        if (address->ssid != ssid) {
            continue;
        }

        patty_list_finish(iter);

        return address;
    }

    patty_list_finish(iter);

error_list_start:
    return NULL;
}

int patty_ax25_if_add_address(patty_ax25_if *iface, const char *callsign, int ssid) {
    patty_ax25_address *address;

    if (find_address(iface, callsign, ssid) != NULL) {
        errno = EEXIST;

        goto error_exists;
    }

    if ((address = malloc(sizeof(*address))) == NULL) {
        goto error_malloc_address;
    }

    memset(address, '\0', sizeof(*address));
    memcpy(address->callsign, callsign, sizeof(address->callsign));

    address->ssid = ssid;

    if ((patty_list_append(iface->addresses, address)) == NULL) {
        goto error_list_append;
    }

    return 0;

error_list_append:
    free(address);

error_malloc_address:
error_exists:
    return -1;
}

int patty_ax25_if_delete_address(patty_ax25_if *iface, const char *callsign, int ssid) {
    patty_list_item *item = iface->addresses->first;
    int i = 0;

    while (item) {
        patty_ax25_address *address = item->value;

        if (strncmp(address->callsign, callsign, sizeof(address->callsign)) == 0 && address->ssid == ssid) {
            if (patty_list_splice(iface->addresses, i) == NULL) {
                goto error_list_splice;
            }
        }

        item = item->next;
        i++;
    }

    return 0;

error_list_splice:
    return -1;
}

patty_ax25_if *patty_ax25_get_if(patty_ax25 *ax25, const char *name) {
    patty_list_iterator *iter;
    patty_ax25_if *iface;

    if ((iter = patty_list_start(ax25->ifaces)) == NULL) {
        goto error_list_start;
    }

    while ((iface = patty_list_next(iter)) != NULL) {
        if (strncmp(iface->name, name, sizeof(iface->name)) == 0) {
            patty_list_finish(iter);

            return iface;
        }
    }

    patty_list_finish(iter);

error_list_start:
    return NULL;
}

int patty_ax25_each_if(patty_ax25 *ax25, int (*callback)(patty_ax25_if *, void *), void *ctx) {
    patty_list_iterator *iter;
    patty_ax25_if *iface;

    if ((iter = patty_list_start(ax25->ifaces)) == NULL) {
        goto error_list_start;
    }

    while ((iface = patty_list_next(iter)) != NULL) {
        if (callback(iface, ctx) < 0) {
            goto error_callback;
        }
    }

    patty_list_finish(iter);

    return 0;

error_callback:
    patty_list_finish(iter);

error_list_start:
    return -1;
}

int patty_ax25_add_if(patty_ax25 *ax25, patty_ax25_if *iface) {
    int fd;

    if ((fd = patty_kiss_tnc_fd(iface->tnc)) >= 0) {
        FD_SET(fd, &ax25->fds);

        if (ax25->fdmax < fd + 1) {
            ax25->fdmax = fd + 1;
        }
    }

    if (patty_dict_set(ax25->fd_lookup, &fd, sizeof(fd), iface) == NULL) {
        goto error_dict_set;
    }

    if (patty_list_append(ax25->ifaces, iface) == NULL) {
        goto error_list_append;
    }

    return 0;

error_list_append:
error_dict_set:
    return -1;
}

int patty_ax25_delete_if(patty_ax25 *ax25, patty_ax25_if *iface) {
    patty_list_item *item = ax25->ifaces->first;

    int fd, i = 0;

    while (item) {
        if (item->value == iface) {
            if (patty_list_splice(ax25->ifaces, i) == NULL) {
                goto error_list_splice;
            }

            return 0;
        }

        item = item->next;
        i++;
    }

    if ((fd = patty_kiss_tnc_fd(iface->tnc)) >= 0) {
        FD_CLR(fd, &ax25->fds);

        if (ax25->fdmax == fd) {
            ax25->fdmax--;
        }

        if (patty_dict_delete(ax25->fd_lookup, &fd, sizeof(fd)) == NULL) {
            goto error_dict_delete;
        }
    }

    return 0;

error_dict_delete:
error_list_splice:
    return -1;
}