/*
 * 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 <nanowasm/nw.h>
#include <nanowasm/types.h>
#include <nw/interp.h>
#include <nw/io.h>
#include <nw/log.h>
#include <nw/routines.h>
#include <stddef.h>
#include <inttypes.h>

static enum nw_state get_bytecode(struct nw_interp *const in)
{
    const struct nw_io_cfg *const cfg = &in->cfg.io;
    struct nw_i_sm_b *const b = &in->sm.bytecode;
    const enum nw_state n = nwp_io_read(cfg, &b->io);

    if (n)
        return n;

    const struct nwp_interp_set *const set = in->set;

    for (size_t i = 0; i < set->n; i++)
        if (b->op == set->opcodes[i])
        {
            nwp_ops.ops[b->op](in);
            return NW_AGAIN;
        }

    static const char exc[] = "invalid opcode";

    LOG("%s: %s: %#" PRIx8 "\n", __func__, exc, b->op);
    in->exception = exc;
    return NW_FATAL;
}

void nwp_interp_limited(struct nw_interp *const i)
{
    struct nw_i_sm_b *const b = &i->sm.bytecode;

    i->next = get_bytecode;
    b->io = (const struct nw_sm_io)
    {
        .buf = &b->op,
        .n = sizeof b->op
    };
}