// function usocket.getaddrinfo(host, port)
STATIC mp_obj_t mod_usocket_getaddrinfo(mp_obj_t host_in, mp_obj_t port_in) {
    mp_uint_t hlen;
    const char *host = mp_obj_str_get_data(host_in, &hlen);
    mp_int_t port = mp_obj_get_int(port_in);

    // find a NIC that can do a name lookup
    for (mp_uint_t i = 0; i < MP_STATE_PORT(mod_network_nic_list).len; i++) {
        mp_obj_t nic = MP_STATE_PORT(mod_network_nic_list).items[i];
        mod_network_nic_type_t *nic_type = (mod_network_nic_type_t*)mp_obj_get_type(nic);
        if (nic_type->gethostbyname != NULL) {
            uint8_t out_ip[MOD_NETWORK_IPADDR_BUF_SIZE];
            int ret = nic_type->gethostbyname(nic, host, hlen, out_ip);
            if (ret != 0) {
                // TODO CPython raises: socket.gaierror: [Errno -2] Name or service not known
                nlr_raise(mp_obj_new_exception_arg1(&mp_type_OSError, MP_OBJ_NEW_SMALL_INT(ret)));
            }
            mp_obj_tuple_t *tuple = mp_obj_new_tuple(5, NULL);
            tuple->items[0] = MP_OBJ_NEW_SMALL_INT(MOD_NETWORK_AF_INET);
            tuple->items[1] = MP_OBJ_NEW_SMALL_INT(MOD_NETWORK_SOCK_STREAM);
            tuple->items[2] = MP_OBJ_NEW_SMALL_INT(0);
            tuple->items[3] = MP_OBJ_NEW_QSTR(MP_QSTR_);
            tuple->items[4] = mod_network_format_inet_addr(out_ip, port);
            return mp_obj_new_list(1, (mp_obj_t*)&tuple);
        }
    }

    nlr_raise(mp_obj_new_exception_msg(&mp_type_OSError, "no available NIC"));
}

STATIC void mp_reset(void) {
    mp_stack_set_top((void*)0x40000000);
    mp_stack_set_limit(8192);
    mp_hal_init();
    gc_init(heap, heap + sizeof(heap));
    mp_init();
    mp_obj_list_init(mp_sys_path, 0);
    mp_obj_list_append(mp_sys_path, MP_OBJ_NEW_QSTR(MP_QSTR_)); // current dir (or base dir of the script)
    mp_obj_list_append(mp_sys_path, MP_OBJ_NEW_QSTR(MP_QSTR__slash_flash_slash_lib));
    mp_obj_list_append(mp_sys_path, MP_OBJ_NEW_QSTR(MP_QSTR__slash_flash));
    mp_obj_list_init(mp_sys_argv, 0);
    MP_STATE_PORT(term_obj) = MP_OBJ_NULL;
    MP_STATE_PORT(dupterm_arr_obj) = MP_OBJ_NULL;
    #if MICROPY_EMIT_XTENSA || MICROPY_EMIT_INLINE_XTENSA
    extern void esp_native_code_init(void);
    esp_native_code_init();
    #endif
    pin_init0();
    readline_init0();
    dupterm_task_init();
#if MICROPY_MODULE_FROZEN
    pyexec_frozen_module("_boot.py");
    pyexec_file("boot.py");
    if (pyexec_mode_kind == PYEXEC_MODE_FRIENDLY_REPL) {
        pyexec_file("main.py");
    }
#endif
}

static mp_obj_t translate(mp_obj_t words) {
    mp_uint_t len, outlen;
    const char *txt = mp_obj_str_get_data(words, &len);
    // Reciter truncates *output* at about 120 characters.
    // So to avoid that we must disallow any input that will exceed that.
    if (len > 80) {
        nlr_raise(mp_obj_new_exception_msg(&mp_type_ValueError, "text too long."));
    }
    reciter_memory *mem = m_new(reciter_memory, 1);
    MP_STATE_PORT(speech_data) = mem;
    for (mp_uint_t i = 0; i < len; i++) {
        mem->input[i] = txt[i];
    }
    mem->input[len] = '[';
    if (!TextToPhonemes(mem)) {
        MP_STATE_PORT(speech_data) = NULL;
        nlr_raise(mp_obj_new_exception_msg(&mp_type_ValueError, "could not parse input."));
    }
    for (outlen = 0; outlen < 255; outlen++) {
        if (mem->input[outlen] == 155) {
            break;
        }
    }
    mp_obj_t res = mp_obj_new_str_of_type(&mp_type_str, (byte *)mem->input, outlen);
    // Prevent input becoming invisible to GC due to tail-call optimisation.
    MP_STATE_PORT(speech_data) = NULL;
    return res;
}MP_DEFINE_CONST_FUN_OBJ_1(translate_obj, translate);

// function usocket.getaddrinfo(host, port)
/// \function getaddrinfo(host, port)
STATIC mp_obj_t mod_usocket_getaddrinfo(mp_obj_t host_in, mp_obj_t port_in) {
    mp_uint_t hlen;
    const char *host = mp_obj_str_get_data(host_in, &hlen);
    mp_int_t port = mp_obj_get_int(port_in);

    // find a NIC that can do a name lookup
    for (mp_uint_t i = 0; i < MP_STATE_PORT(mod_network_nic_list).len; i++) {
        mp_obj_t nic = MP_STATE_PORT(mod_network_nic_list).items[i];
        mod_network_nic_type_t *nic_type = (mod_network_nic_type_t*)mp_obj_get_type(nic);
        if (nic_type->gethostbyname != NULL) {
            // Only IPv4 is supported
            uint8_t out_ip[MOD_NETWORK_IPV4ADDR_BUF_SIZE];
            int32_t result = nic_type->gethostbyname(nic, host, hlen, out_ip, AF_INET);
            if (result != 0) {
                nlr_raise(mp_obj_new_exception_arg1(&mp_type_OSError, MP_OBJ_NEW_SMALL_INT(result)));
            }
            mp_obj_tuple_t *tuple = mp_obj_new_tuple(5, NULL);
            tuple->items[0] = MP_OBJ_NEW_SMALL_INT(AF_INET);
            tuple->items[1] = MP_OBJ_NEW_SMALL_INT(SOCK_STREAM);
            tuple->items[2] = MP_OBJ_NEW_SMALL_INT(0);
            tuple->items[3] = MP_OBJ_NEW_QSTR(MP_QSTR_);
            tuple->items[4] = mod_network_format_inet_addr(out_ip, port);
            return mp_obj_new_list(1, (mp_obj_t*)&tuple);
        }
    }

    nlr_raise(mp_obj_new_exception_msg(&mp_type_OSError, mpexception_os_resource_not_avaliable));
}

void mp_irq_disable_all (void) {
    // re-enable all active callback objects one by one
    for (mp_uint_t i = 0; i < MP_STATE_PORT(mp_irq_obj_list).len; i++) {
        mp_irq_obj_t *callback_obj = ((mp_irq_obj_t *)(MP_STATE_PORT(mp_irq_obj_list).items[i]));
        callback_obj->methods->disable(callback_obj->parent);
    }
}

static int call_dupterm_read(void) {
    nlr_buf_t nlr;
    if (nlr_push(&nlr) == 0) {
        mp_obj_t read_m[3];
        mp_load_method(MP_STATE_PORT(term_obj), MP_QSTR_read, read_m);
        read_m[2] = MP_OBJ_NEW_SMALL_INT(1);
        mp_obj_t res = mp_call_method_n_kw(1, 0, read_m);
        if (res == mp_const_none) {
            return -2;
        }
        mp_buffer_info_t bufinfo;
        mp_get_buffer_raise(res, &bufinfo, MP_BUFFER_READ);
        if (bufinfo.len == 0) {
            mp_printf(&mp_plat_print, "dupterm: EOF received, deactivating\n");
            MP_STATE_PORT(term_obj) = NULL;
            return -1;
        }
        nlr_pop();
        return *(byte*)bufinfo.buf;
    } else {
        // Temporarily disable dupterm to avoid infinite recursion
        mp_obj_t save_term = MP_STATE_PORT(term_obj);
        MP_STATE_PORT(term_obj) = NULL;
        mp_printf(&mp_plat_print, "dupterm: ");
        mp_obj_print_exception(&mp_plat_print, nlr.ret_val);
        MP_STATE_PORT(term_obj) = save_term;
    }

    return -1;
}

STATIC void mp_reset(void) {
    mp_stack_set_top((void*)0x40000000);
    mp_stack_set_limit(8192);
    mp_hal_init();
    gc_init(heap, heap + sizeof(heap));
    mp_init();
    mp_obj_list_init(mp_sys_path, 0);
    mp_obj_list_append(mp_sys_path, MP_OBJ_NEW_QSTR(MP_QSTR_)); // current dir (or base dir of the script)
    mp_obj_list_append(mp_sys_path, MP_OBJ_NEW_QSTR(MP_QSTR__slash_lib));
    mp_obj_list_append(mp_sys_path, MP_OBJ_NEW_QSTR(MP_QSTR__slash_));
    mp_obj_list_init(mp_sys_argv, 0);
    #if MICROPY_VFS_FAT
    memset(MP_STATE_PORT(fs_user_mount), 0, sizeof(MP_STATE_PORT(fs_user_mount)));
    #endif
    MP_STATE_PORT(mp_kbd_exception) = mp_obj_new_exception(&mp_type_KeyboardInterrupt);
    MP_STATE_PORT(term_obj) = MP_OBJ_NULL;
    MP_STATE_PORT(dupterm_arr_obj) = MP_OBJ_NULL;
    pin_init0();
    readline_init0();
    dupterm_task_init();
#if MICROPY_MODULE_FROZEN
    pyexec_frozen_module("_boot.py");
    pyexec_file("boot.py");
    pyexec_file("main.py");
#endif
}

/// \classmethod dict([dict])
/// Get or set the pin mapper dictionary.
STATIC mp_obj_t pin_map_dict(size_t n_args, const mp_obj_t *args) {
    if (n_args > 1) {
        MP_STATE_PORT(pin_class_map_dict) = args[1];
        return mp_const_none;
    }
    return MP_STATE_PORT(pin_class_map_dict);
}

// "path" is the path to lookup; will advance this pointer beyond the volume name.
// Returns logical drive number (-1 means invalid path).
int ff_get_ldnumber (const TCHAR **path) {
    if (!(*path)) {
        return -1;
    }

    if (**path != '/') {
    #if _FS_RPATH
        return ff_CurrVol;
    #else
        return -1;
    #endif
    }

    if (check_path(path, "/flash", 6)) {
        return PD_FLASH;
    }
    else {
        for (mp_uint_t i = 0; i < MP_STATE_PORT(mount_obj_list).len; i++) {
            os_fs_mount_t *mount_obj = ((os_fs_mount_t *)(MP_STATE_PORT(mount_obj_list).items[i]));
            if (check_path(path, mount_obj->path, mount_obj->pathlen)) {
                return mount_obj->vol;
            }
        }
    }

    return -1;
}

mp_obj_t microbit_display_show_func(mp_uint_t n_args, const mp_obj_t *args) {
    // TODO: Support async mode.

    microbit_display_obj_t *self = (microbit_display_obj_t*)args[0];

    // Cancel any animations.
    MP_STATE_PORT(async_data)[0] = NULL;
    MP_STATE_PORT(async_data)[1] = NULL;
    MP_STATE_PORT(async_data)[2] = NULL;

    if (MP_OBJ_IS_STR(args[1])) {
        // arg is a string object
        mp_uint_t len;
        const char *str = mp_obj_str_get_data(args[1], &len);
        if (len == 0) {
            // There are no chars; do nothing.
        } else if (len == 1) {
            // A single char; convert to an image and print that.
            microbit_display_show(self, microbit_image_for_char(str[0]));
        } else {
            mp_int_t delay;
            if (n_args == 3) {
                delay = mp_obj_get_int(args[2]);
            } else {
                delay = MICROBIT_DEFAULT_PRINT_SPEED;
            }
            microbit_display_animate(self, args[1], delay, false, false);
        }
    } else if (mp_obj_get_type(args[1]) == &microbit_image_type) {
        microbit_display_show(self, (microbit_image_obj_t *)args[1]);
    } else {
        nlr_raise(mp_obj_new_exception_msg(&mp_type_TypeError, "expecting an image or a string."));
    }
    return mp_const_none;
}

static int call_dupterm_read(void) {
    if (MP_STATE_PORT(term_obj) == NULL) {
        return -1;
    }

    nlr_buf_t nlr;
    if (nlr_push(&nlr) == 0) {
        mp_obj_t read_m[3];
        mp_load_method(MP_STATE_PORT(term_obj), MP_QSTR_read, read_m);
        read_m[2] = MP_OBJ_NEW_SMALL_INT(1);
        mp_obj_t res = mp_call_method_n_kw(1, 0, read_m);
        if (res == mp_const_none) {
            return -2;
        }
        mp_buffer_info_t bufinfo;
        mp_get_buffer_raise(res, &bufinfo, MP_BUFFER_READ);
        if (bufinfo.len == 0) {
            mp_uos_deactivate("dupterm: EOF received, deactivating\n", MP_OBJ_NULL);
            return -1;
        }
        nlr_pop();
        return *(byte*)bufinfo.buf;
    } else {
        mp_uos_deactivate("dupterm: Exception in read() method, deactivating: ", nlr.ret_val);
    }

    return -1;
}

DSTATUS disk_status (
    BYTE pdrv        /* Physical drive nmuber (0..) */
)
{
    switch (pdrv) {
        case PD_FLASH :
            // flash is ready
            return 0;

#if MICROPY_HW_HAS_SDCARD
        case PD_SDCARD:
            // TODO return STA_PROTECT if SD card is read only
            return 0;
#endif

        case PD_USER:
            if (MP_STATE_PORT(fs_user_mount) == NULL) {
                return STA_NODISK;
            }
            if (MP_STATE_PORT(fs_user_mount)->writeblocks[0] == MP_OBJ_NULL) {
                return STA_PROTECT;
            }
            return 0;
    }

    return STA_NOINIT;
}

DSTATUS disk_initialize (
    BYTE pdrv                /* Physical drive nmuber (0..) */
)
{
    switch (pdrv) {
        case PD_FLASH:
            storage_init();
            return 0;

#if MICROPY_HW_HAS_SDCARD
        case PD_SDCARD:
            if (!sdcard_power_on()) {
                return STA_NODISK;
            }
            // TODO return STA_PROTECT if SD card is read only
            return 0;
#endif

        case PD_USER:
            if (MP_STATE_PORT(fs_user_mount) == NULL) {
                return STA_NODISK;
            }
            if (MP_STATE_PORT(fs_user_mount)->writeblocks[0] == MP_OBJ_NULL) {
                return STA_PROTECT;
            }
            return 0;
    }

    return STA_NOINIT;
}

DRESULT disk_ioctl (
    BYTE pdrv,        /* Physical drive nmuber (0..) */
    BYTE cmd,        /* Control code */
    void *buff        /* Buffer to send/receive control data */
)
{
    switch (pdrv) {
        case PD_FLASH:
            switch (cmd) {
                case CTRL_SYNC:
                    storage_flush();
                    return RES_OK;

                case GET_BLOCK_SIZE:
                    *((DWORD*)buff) = 1; // high-level sector erase size in units of the small (512) block size
                    return RES_OK;
            }
            break;

#if MICROPY_HW_HAS_SDCARD
        case PD_SDCARD:
            switch (cmd) {
                case CTRL_SYNC:
                    return RES_OK;

                case GET_BLOCK_SIZE:
                    *((DWORD*)buff) = 1; // high-level sector erase size in units of the small (512) block size
                    return RES_OK;
            }
            break;
#endif

        case PD_USER:
            if (MP_STATE_PORT(fs_user_mount) == NULL) {
                // nothing mounted
                return RES_ERROR;
            }
            switch (cmd) {
                case CTRL_SYNC:
                    if (MP_STATE_PORT(fs_user_mount)->sync[0] != MP_OBJ_NULL) {
                        mp_call_method_n_kw(0, 0, MP_STATE_PORT(fs_user_mount)->sync);
                    }
                    return RES_OK;

                case GET_BLOCK_SIZE:
                    *((DWORD*)buff) = 1; // high-level sector erase size in units of the small (512) bl
                    return RES_OK;

                case GET_SECTOR_COUNT: {
                    mp_obj_t ret = mp_call_method_n_kw(0, 0, MP_STATE_PORT(fs_user_mount)->count);
                    *((DWORD*)buff) = mp_obj_get_int(ret);
                    return RES_OK;
                }
            }
            break;
    }

    return RES_PARERR;
}

void usb_vcp_set_interrupt_char(int c) {
    if (pyb_usb_flags & PYB_USB_FLAG_DEV_ENABLED) {
        if (c != -1) {
            mp_obj_exception_clear_traceback(MP_STATE_PORT(mp_const_vcp_interrupt));
        }
        USBD_CDC_SetInterrupt(c, MP_STATE_PORT(mp_const_vcp_interrupt));
    }
}

void mp_hal_stdout_tx_strn(const char *str, size_t len) {
    if (MP_STATE_PORT(pyb_stdio_uart) != NULL) {
        uart_tx_strn(MP_STATE_PORT(pyb_stdio_uart), str, len);
    }
    if (usb_vcp_is_enabled()) {
        usb_vcp_send_strn(str, len);
    }
}

void can_deinit(void) {
    for (int i = 0; i < MP_ARRAY_SIZE(MP_STATE_PORT(pyb_can_obj_all)); i++) {
        pyb_can_obj_t *can_obj = MP_STATE_PORT(pyb_can_obj_all)[i];
        if (can_obj != NULL) {
            pyb_can_deinit(can_obj);
        }
    }
}

mp_obj_t microbit_display_show_func(mp_uint_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {

    // Cancel any animations.
    MP_STATE_PORT(async_data)[0] = NULL;
    MP_STATE_PORT(async_data)[1] = NULL;

    static const mp_arg_t show_allowed_args[] = {
        { MP_QSTR_image,    MP_ARG_REQUIRED | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },

// unregister all interrupt sources
void uart_deinit(void) {
    for (int i = 0; i < MP_ARRAY_SIZE(MP_STATE_PORT(pyb_uart_obj_all)); i++) {
        pyb_uart_obj_t *uart_obj = MP_STATE_PORT(pyb_uart_obj_all)[i];
        if (uart_obj != NULL) {
            pyb_uart_deinit(uart_obj);
        }
    }
}

mp_irq_obj_t *mp_irq_find (mp_obj_t parent) {
    for (mp_uint_t i = 0; i < MP_STATE_PORT(mp_irq_obj_list).len; i++) {
        mp_irq_obj_t *callback_obj = ((mp_irq_obj_t *)(MP_STATE_PORT(mp_irq_obj_list).items[i]));
        if (callback_obj->parent == parent) {
            return callback_obj;
        }
    }
    return NULL;
}