// SPDX-FileCopyrightText: 2024 Himbeer <himbeer@disroot.org>
//
// SPDX-License-Identifier: AGPL-3.0-or-later

const std = @import("std");

const instructions = @import("../instructions.zig");
const sbi = @import("../sbi.zig");

const ExtId = enum(usize) {
    SetTimer = 0x00,
    ConsolePutchar = 0x01,
    ConsoleGetchar = 0x02,
    ClearIpi = 0x03,
    SendIpi = 0x04,
    RemoteFenceI = 0x05,
    RemoteSFenceVma = 0x06,
    RemoteSFenceVmaAsid = 0x07,
    Shutdown = 0x08,
};

pub const Writer = std.io.Writer(void, sbi.Error, write);

fn write(_: void, bytes: []const u8) !usize {
    for (bytes) |byte| {
        const ret = instructions.ecall(@intFromEnum(ExtId.ConsolePutchar), 0, byte, 0, 0);
        if (ret.err != 0) {
            return sbi.errorFromCode(ret.err);
        }
    }

    return bytes.len;
}

pub fn writer() !Writer {
    if (!try sbi.probeExt(@intFromEnum(ExtId.ConsolePutchar))) {
        return sbi.Error.NotSupported;
    }

    return .{ .context = {} };
}