#include "tmp.h"
#include "type.h"
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>

const struct stentry *tmp_create(struct fn *fn, const struct type *t)
{
    static const char fmt[] = "__tmp%zu";
    int r = snprintf(NULL, 0, fmt, fn->ntmps);
    char *s = NULL, *tname = NULL;
    struct tmp *tmp;

    if (!(tname = type_name(t)))
        goto failure;
    else if (r < 0)
    {
        fprintf(stderr, "%s: snprintf(3) failed\n", __func__);
        goto failure;
    }
    else if (!(s = malloc(r + 1)))
    {
        perror("malloc(3)");
        goto failure;
    }

    snprintf(s, r + 1, fmt, fn->ntmps++);

    if (!(tmp = malloc(sizeof *tmp)))
    {
        perror("realloc(3)");
        goto failure;
    }

    *tmp = (struct tmp)
    {
        .tk =
        {
            .type = ID,
            .s = s,
            .loc.f = "(temporary)"
        },

        .e =
        {
            .tk = &tmp->tk,
            .t = t
        }
    };

    if (!fn->tmps)
        fn->tmps = tmp;
    else
        for (struct tmp *t = fn->tmps; t ; t = t->next)
            if (!t->next)
            {
                t->next = tmp;
                break;
            }

    fprintf(stderr, "\tcreating temporary variable %s, type %s\n", s, tname);
    free(tname);
    return &tmp->e;

failure:
    free(s);
    free(tname);
    return NULL;
}