/*
 * This file is part of the MicroPython project, http://micropython.org/
 *
 * The MIT License (MIT)
 *
 * Copyright (c) 2019 Damien P. George
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

#include "py/mpstate.h"
#include "py/mphal.h"
#include "lib/utils/interrupt_char.h"
#include "samd_soc.h"
#include "tusb.h"

#if MICROPY_KBD_EXCEPTION

void tud_cdc_rx_wanted_cb(uint8_t itf, char wanted_char) {
    (void)itf;
    (void)wanted_char;
    tud_cdc_read_char(); // discard interrupt char
    mp_keyboard_interrupt();
}

void mp_hal_set_interrupt_char(int c) {
    if (c != -1) {
        mp_obj_exception_clear_traceback(MP_OBJ_FROM_PTR(&MP_STATE_VM(mp_kbd_exception)));
    }
    tud_cdc_set_wanted_char(c);
}

void mp_keyboard_interrupt(void) {
    MP_STATE_VM(mp_pending_exception) = MP_OBJ_FROM_PTR(&MP_STATE_VM(mp_kbd_exception));
    #if MICROPY_ENABLE_SCHEDULER
    if (MP_STATE_VM(sched_state) == MP_SCHED_IDLE) {
        MP_STATE_VM(sched_state) = MP_SCHED_PENDING;
    }
    #endif
}

#endif

void mp_hal_delay_ms(mp_uint_t ms) {
    ms += 1;
    uint32_t t0 = systick_ms;
    while (systick_ms - t0 < ms) {
        MICROPY_EVENT_POLL_HOOK
    }
}

void mp_hal_delay_us(mp_uint_t us) {
    uint32_t ms = us / 1000 + 1;
    uint32_t t0 = systick_ms;
    while (systick_ms - t0 < ms) {
        __WFI();
    }
}

int mp_hal_stdin_rx_chr(void) {
    for (;;) {
        if (USARTx->USART.INTFLAG.bit.RXC) {
            return USARTx->USART.DATA.bit.DATA;
        }
        if (tud_cdc_connected() && tud_cdc_available()) {
            uint8_t buf[1];
            uint32_t count = tud_cdc_read(buf, sizeof(buf));
            if (count) {
                return buf[0];
            }
        }
        __WFI();
    }
}

void mp_hal_stdout_tx_strn(const char *str, mp_uint_t len) {
    if (tud_cdc_connected()) {
        for (size_t i = 0; i < len;) {
            uint32_t n = len - i;
            uint32_t n2 = tud_cdc_write(str + i, n);
            if (n2 < n) {
                while (!tud_cdc_write_flush()) {
                    __WFI();
                }
            }
            i += n2;
        }
        while (!tud_cdc_write_flush()) {
            __WFI();
        }
    }
    while (len--) {
        while (!(USARTx->USART.INTFLAG.bit.DRE)) { }
        USARTx->USART.DATA.bit.DATA = *str++;
    }
}
