/* This file is part of the YAZ toolkit.
 * Copyright (C) Index Data
 * See the file LICENSE for details.
 */

/**
 * \file odr_choice.c
 * \brief Implements ODR CHOICE codec
 */

#if HAVE_CONFIG_H
#include <config.h>
#endif

#include "odr-priv.h"

int odr_choice(ODR o, Odr_arm arm[], void *p, void *whichp,
               const char *name)
{
    int i, cl = -1, tg, cn, *which = (int *)whichp, bias = o->op->choice_bias;

    if (o->error)
        return 0;
    if (o->direction != ODR_DECODE && !*(char**)p)
        return 0;

    if (o->direction == ODR_DECODE)
    {
        *which = -1;
        *(char**)p = 0;
    }
    o->op->choice_bias = -1;

    if (o->direction == ODR_PRINT)
    {
        if (name)
        {
            odr_prname(o, name);
            odr_printf(o, "choice\n");
        }
    }
    for (i = 0; arm[i].fun; i++)
    {
        if (o->direction == ODR_DECODE)
        {
            if (bias >= 0 && bias != arm[i].which)
                continue;
            *which = arm[i].which;
        }
        else if (*which != arm[i].which)
            continue;

        if (arm[i].tagmode != ODR_NONE)
        {
            if (o->direction == ODR_DECODE && cl < 0)
            {
                if (o->op->stack_top && !odr_constructed_more(o))
                    return 0;
                if (ber_dectag(o->op->bp, &cl, &tg, &cn, odr_max(o)) <= 0)
                    return 0;
            }
            else if (o->direction != ODR_DECODE)
            {
                cl = arm[i].zclass;
                tg = arm[i].tag;
            }
            if (tg == arm[i].tag && cl == arm[i].zclass)
            {
                if (arm[i].tagmode == ODR_IMPLICIT)
                {
                    odr_implicit_settag(o, cl, tg);
                    return (*arm[i].fun)(o, (char **)p, 0, arm[i].name);
                }
                /* explicit */
                if (!odr_constructed_begin(o, p, cl, tg, 0))
                    return 0;
                return (*arm[i].fun)(o, (char **)p, 0, arm[i].name) &&
                    odr_constructed_end(o);
            }
        }
        else  /* no tagging. Have to poll type */
        {
            if ((*arm[i].fun)(o, (char **)p, 1, arm[i].name) && *(char**)p)
                return 1;
        }
    }
    return 0;
}

void odr_choice_bias(ODR o, int what)
{
    if (o->op->enable_bias)
        o->op->choice_bias = what;
}

void odr_choice_enable_bias (ODR o, int mode)
{
    o->op->enable_bias = mode;
}
/*
 * Local variables:
 * c-basic-offset: 4
 * c-file-style: "Stroustrup"
 * indent-tabs-mode: nil
 * End:
 * vim: shiftwidth=4 tabstop=8 expandtab
 */