/*
 * nanowasm, a tiny WebAssembly/Wasm interpreter
 * Copyright (C) 2023-2024  Xavier Del Campo Romero
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at https://mozilla.org/MPL/2.0/.
 */

#include <nw/log.h>
#include <nw/ops.h>
#include <nanowasm/nw.h>
#include <nw/types.h>
#include <nw/interp.h>
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
#include <string.h>

static int get_i32(struct nw_interp *const i, const void *const data,
    const varuint32 idx)
{
    const int32_t *const src = (const int32_t *)data + idx;

    return interp_stack_push(i, src, sizeof (*src));
}

static int get_i64(struct nw_interp *const i, const void *const data,
    const varuint32 idx)
{
    const int64_t *const src = (const int64_t *)data + idx;

    return interp_stack_push(i, src, sizeof (*src));
}

static int get_f32(struct nw_interp *const i, const void *const data,
    const varuint32 idx)
{
    const float *const src = (const float *)data + idx;

    return interp_stack_push(i, src, sizeof (*src));
}

static int get_f64(struct nw_interp *const i, const void *const data,
    const varuint32 idx)
{
    const double *const src = (const double *)data + idx;

    return interp_stack_push(i, src, sizeof (*src));
}

static int get_local(const varuint32 local_index, struct nw_interp *const i)
{
    struct nw_locals *l;
    varuint32 idx;

    if (locals_get(local_index, i, &l, &idx))
    {
        LOG("%s: locals_get failed\n", __func__);
        return -1;
    }

    static int (*const get[])(struct nw_interp *, const void *,
        varuint32) =
    {
        [VALUE_TYPE_I32] = get_i32,
        [VALUE_TYPE_I64] = get_i64,
        [VALUE_TYPE_F32] = get_f32,
        [VALUE_TYPE_F64] = get_f64,
    };

    if (get[l->type](i, l + 1, idx))
    {
        LOG("%s: get type %d failed\n", __func__, l->type);
        return -1;
    }

    return 0;
}

static int op(struct nw_interp *const i, FILE *const f)
{
    varuint32 local_index;

    if (varuint32_read(f, &local_index))
    {
        LOG("%s: varuint32_read failed\n", __func__);
        return 1;
    }
    else if (i && get_local(local_index, i))
    {
        LOG("%s: get_local failed\n", __func__);
        return -1;
    }

    return 0;
}

int op_get_local(struct nw_interp *const i)
{
    return op(i, i->f);
}

int check_get_local(FILE *const f)
{
    return op(NULL, f);
}