//go:build linux && cgo

// Copyright (c) 2026 Storm Dragon
// Authors: Storm Dragon, Angus Kola
// SPDX-License-Identifier: GPL-3.0-or-later

package speech

/*
#include <errno.h>
#include <fcntl.h>
#include <termios.h>
#include <unistd.h>
#include <stdlib.h>

static int cth_serial_open(const char *device, int baud) {
    speed_t speed;
    switch (baud) {
        case 1200: speed = B1200; break;
        case 2400: speed = B2400; break;
        case 4800: speed = B4800; break;
        case 9600: speed = B9600; break;
        case 19200: speed = B19200; break;
        case 38400: speed = B38400; break;
        case 57600: speed = B57600; break;
        case 115200: speed = B115200; break;
        default: return -EINVAL;
    }
    int fd = open(device, O_RDWR | O_NOCTTY | O_NONBLOCK | O_CLOEXEC);
    if (fd < 0) return -errno;
    struct termios attrs;
    if (tcgetattr(fd, &attrs) < 0) { int error = errno; close(fd); return -error; }
    cfmakeraw(&attrs);
    attrs.c_cflag |= CLOCAL | CREAD;
    attrs.c_cc[VMIN] = attrs.c_cc[VTIME] = 0;
    if (cfsetispeed(&attrs, speed) < 0 || cfsetospeed(&attrs, speed) < 0 ||
        tcsetattr(fd, TCSANOW, &attrs) < 0) { int error = errno; close(fd); return -error; }
    return fd;
}
static int cth_serial_flush(int fd) { return tcflush(fd, TCOFLUSH) < 0 ? errno : 0; }
*/
import "C"

import (
	"fmt"
	"syscall"
	"unsafe"
)

func open_serial(device string, baud int) (int, error) {
	value := C.CString(device)
	defer C.free(unsafe.Pointer(value))
	fd := int(C.cth_serial_open(value, C.int(baud)))
	if fd < 0 {
		return -1, fmt.Errorf("open hardware speech device: %w", syscall.Errno(-fd))
	}
	return fd, nil
}

func flush_serial(fd int) error {
	if code := C.cth_serial_flush(C.int(fd)); code != 0 {
		return fmt.Errorf("flush hardware speech: %w", syscall.Errno(code))
	}
	return nil
}