#include <stdlib.h>
#include <assert.h>
#include <libssh/callbacks.h>
#include <libssh/server.h>

#include "server_ssh.h"
#include "log.h"

typedef struct ssh_data {
    ssh_bind sshbind;
    ssh_session session;
} ssh_data;

struct fwd_callbacks potd_ssh_callbacks = {
    .on_listen = ssh_on_listen,
    .on_shutdown = ssh_on_shutdown
};

static int set_default_keys(ssh_bind sshbind, int rsa_already_set,
                            int dsa_already_set, int ecdsa_already_set);


int ssh_init_cb(struct forward_ctx *ctx)
{
    ctx->fwd_cbs = potd_ssh_callbacks;

    if (ssh_init())
        return 1;
    ssh_data *d = (ssh_data *) calloc(1, sizeof(*d));
    assert(d);
    d->sshbind = ssh_bind_new();
    d->session = ssh_new();
    ctx->data = d;
    if (!d->sshbind || !d->session)
        return 1;
    if (set_default_keys(d->sshbind, 0, 0, 0))
        return 1;

    return 0;
}

int ssh_on_listen(struct forward_ctx *ctx)
{
    ssh_data *d = (ssh_data *) ctx->data;

    if (ssh_bind_listen(d->sshbind) < 0) {
        E("Error listening to SSH socket: %s", ssh_get_error(d->sshbind));
    }
    return 0;
}

int ssh_on_shutdown(struct forward_ctx *ctx)
{
    return 0;
}

static int set_default_keys(ssh_bind sshbind, int rsa_already_set,
                             int dsa_already_set, int ecdsa_already_set)
{
    if (!rsa_already_set) {
        if (ssh_bind_options_set(sshbind, SSH_BIND_OPTIONS_RSAKEY,
                                 "./ssh_host_rsa_key"))
            return 1;
    }
    if (!dsa_already_set) {
        if (ssh_bind_options_set(sshbind, SSH_BIND_OPTIONS_DSAKEY,
                                 "./ssh_host_dsa_key"))
            return 1;
    }
    if (!ecdsa_already_set) {
        if (ssh_bind_options_set(sshbind, SSH_BIND_OPTIONS_ECDSAKEY,
                                 "./ssh_host_ecdsa_key"))
            return 1;
    }
    return 0;
}