/*
 * This file is part of the MicroPython project, http://micropython.org/
 *
 * The MIT License (MIT)
 *
 * Copyright (c) 2013-2016 Damien P. George
 * Copyright (c) 2016 Paul Sokolovsky
 *
 * 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/mpconfig.h"
#if MICROPY_PY_UTIME_MP_HAL

#include <string.h>

#include "py/obj.h"
#include "py/mphal.h"
#include "py/smallint.h"
#include "py/runtime.h"
#include "extmod/utime_mphal.h"
#include "shared/timeutils/timeutils.h"

// mktime()
// This is the inverse function of localtime. Its argument is a full 8-tuple
// which expresses a time as per localtime. It returns an integer which is
// the number of seconds since the Epoch (eg 1st Jan 1970, or 1st Jan 2000).
STATIC mp_obj_t time_mktime(mp_obj_t tuple) {
    size_t len;
    mp_obj_t *elem;
    mp_obj_get_array(tuple, &len, &elem);

    // localtime generates a tuple of len 8. CPython uses 9, so we accept both.
    if (len < 8 || len > 9) {
        mp_raise_TypeError(MP_ERROR_TEXT("mktime needs a tuple of length 8 or 9"));
    }

    return mp_obj_new_int_from_uint(timeutils_mktime(mp_obj_get_int(elem[0]),
        mp_obj_get_int(elem[1]), mp_obj_get_int(elem[2]), mp_obj_get_int(elem[3]),
        mp_obj_get_int(elem[4]), mp_obj_get_int(elem[5])));
}
MP_DEFINE_CONST_FUN_OBJ_1(mp_utime_mktime_obj, time_mktime);

STATIC mp_obj_t time_sleep(mp_obj_t seconds_o) {
    #if MICROPY_PY_BUILTINS_FLOAT
    mp_hal_delay_ms((mp_uint_t)(1000 * mp_obj_get_float(seconds_o)));
    #else
    mp_hal_delay_ms(1000 * mp_obj_get_int(seconds_o));
    #endif
    return mp_const_none;
}
MP_DEFINE_CONST_FUN_OBJ_1(mp_utime_sleep_obj, time_sleep);

STATIC mp_obj_t time_sleep_ms(mp_obj_t arg) {
    mp_int_t ms = mp_obj_get_int(arg);
    if (ms >= 0) {
        mp_hal_delay_ms(ms);
    }
    return mp_const_none;
}
MP_DEFINE_CONST_FUN_OBJ_1(mp_utime_sleep_ms_obj, time_sleep_ms);

STATIC mp_obj_t time_sleep_us(mp_obj_t arg) {
    mp_int_t us = mp_obj_get_int(arg);
    if (us > 0) {
        mp_hal_delay_us(us);
    }
    return mp_const_none;
}
MP_DEFINE_CONST_FUN_OBJ_1(mp_utime_sleep_us_obj, time_sleep_us);

STATIC mp_obj_t time_ticks_ms(void) {
    return MP_OBJ_NEW_SMALL_INT(mp_hal_ticks_ms() & (MICROPY_PY_UTIME_TICKS_PERIOD - 1));
}
MP_DEFINE_CONST_FUN_OBJ_0(mp_utime_ticks_ms_obj, time_ticks_ms);

STATIC mp_obj_t time_ticks_us(void) {
    return MP_OBJ_NEW_SMALL_INT(mp_hal_ticks_us() & (MICROPY_PY_UTIME_TICKS_PERIOD - 1));
}
MP_DEFINE_CONST_FUN_OBJ_0(mp_utime_ticks_us_obj, time_ticks_us);

STATIC mp_obj_t time_ticks_cpu(void) {
    return MP_OBJ_NEW_SMALL_INT(mp_hal_ticks_cpu() & (MICROPY_PY_UTIME_TICKS_PERIOD - 1));
}
MP_DEFINE_CONST_FUN_OBJ_0(mp_utime_ticks_cpu_obj, time_ticks_cpu);

STATIC mp_obj_t time_ticks_diff(mp_obj_t end_in, mp_obj_t start_in) {
    // we assume that the arguments come from ticks_xx so are small ints
    mp_uint_t start = MP_OBJ_SMALL_INT_VALUE(start_in);
    mp_uint_t end = MP_OBJ_SMALL_INT_VALUE(end_in);
    // Optimized formula avoiding if conditions. We adjust difference "forward",
    // wrap it around and adjust back.
    mp_int_t diff = ((end - start + MICROPY_PY_UTIME_TICKS_PERIOD / 2) & (MICROPY_PY_UTIME_TICKS_PERIOD - 1))
        - MICROPY_PY_UTIME_TICKS_PERIOD / 2;
    return MP_OBJ_NEW_SMALL_INT(diff);
}
MP_DEFINE_CONST_FUN_OBJ_2(mp_utime_ticks_diff_obj, time_ticks_diff);

STATIC mp_obj_t time_ticks_add(mp_obj_t ticks_in, mp_obj_t delta_in) {
    // we assume that first argument come from ticks_xx so is small int
    mp_uint_t ticks = MP_OBJ_SMALL_INT_VALUE(ticks_in);
    mp_uint_t delta = mp_obj_get_int(delta_in);

    // Check that delta does not overflow the range that ticks_diff can handle.
    // This ensures the following:
    //  - ticks_diff(ticks_add(T, delta), T) == delta
    //  - ticks_diff(T, ticks_add(T, delta)) == -delta
    // The latter requires excluding delta=-TICKS_PERIOD/2.
    //
    // This unsigned comparison is equivalent to a signed comparison of:
    //   delta <= -TICKS_PERIOD/2 || delta >= TICKS_PERIOD/2
    if (delta + MICROPY_PY_UTIME_TICKS_PERIOD / 2 - 1 >= MICROPY_PY_UTIME_TICKS_PERIOD - 1) {
        mp_raise_msg(&mp_type_OverflowError, MP_ERROR_TEXT("ticks interval overflow"));
    }

    return MP_OBJ_NEW_SMALL_INT((ticks + delta) & (MICROPY_PY_UTIME_TICKS_PERIOD - 1));
}
MP_DEFINE_CONST_FUN_OBJ_2(mp_utime_ticks_add_obj, time_ticks_add);

// Returns the number of nanoseconds since the Epoch, as an integer.
STATIC mp_obj_t time_time_ns(void) {
    return mp_obj_new_int_from_ull(mp_hal_time_ns());
}
MP_DEFINE_CONST_FUN_OBJ_0(mp_utime_time_ns_obj, time_time_ns);

#endif // MICROPY_PY_UTIME_MP_HAL