2024-08-03 09:39:02 -04:00

356 lines
11 KiB
C

/*
* MIT License
*
* Copyright (c) 2021 Joey Castillo
*
* 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 <math.h>
#include "watch_utility.h"
const char * watch_utility_get_weekday(watch_date_time date_time) {
static const char weekdays[7][3] = {"MO", "TU", "WE", "TH", "FR", "SA", "SU"};
return weekdays[watch_utility_get_iso8601_weekday_number(date_time.unit.year + WATCH_RTC_REFERENCE_YEAR, date_time.unit.month, date_time.unit.day) - 1];
}
// Per ISO8601 week starts on Monday with index 1
uint8_t watch_utility_get_iso8601_weekday_number(uint16_t year, uint8_t month, uint8_t day) {
year -= WATCH_RTC_REFERENCE_YEAR;
year += 20;
if (month <= 2) {
month += 12;
year--;
}
return ((day + (13 * (month + 1) / 5) + year + (year / 4) + 5) % 7) + 1;
}
// this function is from the excellent musl c library
uint8_t watch_utility_get_weeknumber(uint16_t year, uint8_t month, uint8_t day) {
uint8_t weekday;
uint16_t days;
if (use_iso_8601_weeknumber == 1) {
weekday = ((watch_utility_get_iso8601_weekday_number(year, month, day) + 5) % 7) + 1;
} else {
weekday = watch_utility_get_iso8601_weekday_number(year, month, day) % 7;
}
days = watch_utility_days_since_new_year(year, month, day);
int val = (days + 7U - (weekday+6U)%7) / 7;
/* If 1 Jan is just 1-3 days past Monday,
* the previous week is also in this year. */
if ((weekday + 371U - days - 2) % 7 <= 2)
val++;
if (!val) {
val = 52;
/* If 31 December of prev year a Thursday,
* or Friday of a leap year, then the
* prev year has 53 weeks. */
int dec31 = (weekday + 7U - days - 1) % 7;
if (dec31 == 4 || (dec31 == 5 && is_leap(year%400-1)))
val++;
} else if (val == 53) {
/* If 1 January is not a Thursday, and not
* a Wednesday of a leap year, then this
* year has only 52 weeks. */
int jan1 = (weekday + 371U - days) % 7;
if (jan1 != 4 && (jan1 != 3 || !is_leap(year)))
val = 1;
}
return val;
}
uint8_t is_leap(uint16_t y)
{
y += 1900;
return !(y%4) && ((y%100) || !(y%400));
}
uint8_t get_dst_status(watch_date_time date_time) {
watch_date_time dst_start_time;
watch_date_time dst_end_time;
uint32_t unix_dst_start_time;
uint32_t unix_dst_end_time;
uint32_t unix_curr_time;
dst_start_time.unit.year = date_time.unit.year;
dst_start_time.unit.month = 3;
dst_start_time.unit.hour = 2;
dst_start_time.unit.minute = 0;
dst_start_time.unit.second = 0;
dst_start_time.unit.day = 15 - watch_utility_get_iso8601_weekday_number(dst_start_time.unit.year + WATCH_RTC_REFERENCE_YEAR, dst_start_time.unit.month, 1);
unix_dst_start_time = watch_utility_date_time_to_unix_time(dst_start_time, 0);
dst_end_time.unit.year = date_time.unit.year;
dst_end_time.unit.month = 11;
dst_end_time.unit.hour = 2;
dst_end_time.unit.minute = 0;
dst_end_time.unit.second = 0;
dst_end_time.unit.day = 15 - watch_utility_get_iso8601_weekday_number(dst_end_time.unit.year + WATCH_RTC_REFERENCE_YEAR, dst_end_time.unit.month, 1);
unix_dst_end_time = watch_utility_date_time_to_unix_time(dst_end_time, 0);
if (date_time.unit.second > 45) // In emu, it's been seen that we may trigger at 59sec rather than exactly 0 each time
date_time.unit.minute = (date_time.unit.minute + 1) % 60;
date_time.unit.second = 0;
unix_curr_time = watch_utility_date_time_to_unix_time(date_time, 0);
if (unix_curr_time == unix_dst_start_time) return DST_STARTING;
if (unix_curr_time == unix_dst_end_time) return DST_ENDING;
if (unix_curr_time > unix_dst_end_time || unix_curr_time < unix_dst_start_time) return DST_ENDED;
return DST_OCCURRING;
}
bool dst_occurring(watch_date_time date_time) {
return get_dst_status(date_time) <= DST_OCCURRING;
}
uint16_t watch_utility_days_since_new_year(uint16_t year, uint8_t month, uint8_t day) {
uint16_t DAYS_SO_FAR[] = {
0, // Jan
31, // Feb
59, // March
90, // April
120, // May
151, // June
181, // July
212, // August
243, // September
273, // October
304, // November
334 // December
};
return (is_leap(year) && (month > 2) ? 1 : 0) + DAYS_SO_FAR[month - 1] + day;
}
// Function taken from `src/time/__year_to_secs.c` of musl libc
// https://musl.libc.org
static uint32_t __year_to_secs(uint32_t year, int *is_leap)
{
if (year-2ULL <= 136) {
int y = year;
int leaps = (y-68)>>2;
if (!((y-68)&3)) {
leaps--;
if (is_leap) *is_leap = 1;
} else if (is_leap) *is_leap = 0;
return 31536000*(y-70) + 86400*leaps;
}
int cycles, centuries, leaps, rem;
if (!is_leap) is_leap = &(int){0};
cycles = (year-100) / 400;
rem = (year-100) % 400;
if (rem < 0) {
cycles--;
rem += 400;
}
if (!rem) {
*is_leap = 1;
centuries = 0;
leaps = 0;
} else {
if (rem >= 200) {
if (rem >= 300) centuries = 3, rem -= 300;
else centuries = 2, rem -= 200;
} else {
if (rem >= 100) centuries = 1, rem -= 100;
else centuries = 0;
}
if (!rem) {
*is_leap = 0;
leaps = 0;
} else {
leaps = rem / 4U;
rem %= 4U;
*is_leap = !rem;
}
}
leaps += 97*cycles + 24*centuries - *is_leap;
return (year-100) * 31536000LL + leaps * 86400LL + 946684800 + 86400;
}
// Function taken from `src/time/__month_to_secs.c` of musl libc
// https://musl.libc.org
static int __month_to_secs(int month, int is_leap)
{
static const int secs_through_month[] = {
0, 31*86400, 59*86400, 90*86400,
120*86400, 151*86400, 181*86400, 212*86400,
243*86400, 273*86400, 304*86400, 334*86400 };
int t = secs_through_month[month];
if (is_leap && month >= 2) t+=86400;
return t;
}
// Function adapted from `src/time/__tm_to_secs.c` of musl libc
// https://musl.libc.org
uint32_t watch_utility_convert_to_unix_time(uint16_t year, uint8_t month, uint8_t day, uint8_t hour, uint8_t minute, uint8_t second, uint32_t utc_offset) {
int is_leap;
// POSIX tm struct starts year at 1900 and month at 0
// https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/time.h.html
uint32_t timestamp = __year_to_secs(year - 1900, &is_leap);
timestamp += __month_to_secs(month - 1, is_leap);
// Regular conversion from musl libc
timestamp += (day - 1) * 86400;
timestamp += hour * 3600;
timestamp += minute * 60;
timestamp += second;
timestamp -= utc_offset;
return timestamp;
}
uint32_t watch_utility_date_time_to_unix_time(watch_date_time date_time, uint32_t utc_offset) {
return watch_utility_convert_to_unix_time(date_time.unit.year + WATCH_RTC_REFERENCE_YEAR, date_time.unit.month, date_time.unit.day, date_time.unit.hour, date_time.unit.minute, date_time.unit.second, utc_offset);
}
#define LEAPOCH (946684800LL + 86400*(31+29))
#define DAYS_PER_400Y (365*400 + 97)
#define DAYS_PER_100Y (365*100 + 24)
#define DAYS_PER_4Y (365*4 + 1)
watch_date_time watch_utility_date_time_from_unix_time(uint32_t timestamp, uint32_t utc_offset) {
watch_date_time retval;
retval.reg = 0;
int32_t days, secs;
int32_t remdays, remsecs, remyears;
int32_t qc_cycles, c_cycles, q_cycles;
int32_t years, months;
int32_t wday, yday, leap;
static const int8_t days_in_month[] = {31,30,31,30,31,31,30,31,30,31,31,29};
timestamp += utc_offset;
secs = timestamp - LEAPOCH;
days = secs / 86400;
remsecs = secs % 86400;
if (remsecs < 0) {
remsecs += 86400;
days--;
}
wday = (3+days)%7;
if (wday < 0) wday += 7;
qc_cycles = (int)(days / DAYS_PER_400Y);
remdays = days % DAYS_PER_400Y;
if (remdays < 0) {
remdays += DAYS_PER_400Y;
qc_cycles--;
}
c_cycles = remdays / DAYS_PER_100Y;
if (c_cycles == 4) c_cycles--;
remdays -= c_cycles * DAYS_PER_100Y;
q_cycles = remdays / DAYS_PER_4Y;
if (q_cycles == 25) q_cycles--;
remdays -= q_cycles * DAYS_PER_4Y;
remyears = remdays / 365;
if (remyears == 4) remyears--;
remdays -= remyears * 365;
leap = !remyears && (q_cycles || !c_cycles);
yday = remdays + 31 + 28 + leap;
if (yday >= 365+leap) yday -= 365+leap;
years = remyears + 4*q_cycles + 100*c_cycles + 400*qc_cycles;
for (months=0; days_in_month[months] <= remdays; months++)
remdays -= days_in_month[months];
years += 2000;
months += 2;
if (months >= 12) {
months -=12;
years++;
}
if (years < 2020 || years > 2083) return retval;
retval.unit.year = years - WATCH_RTC_REFERENCE_YEAR;
retval.unit.month = months + 1;
retval.unit.day = remdays + 1;
retval.unit.hour = remsecs / 3600;
retval.unit.minute = remsecs / 60 % 60;
retval.unit.second = remsecs % 60;
return retval;
}
watch_date_time watch_utility_date_time_convert_zone(watch_date_time date_time, uint32_t origin_utc_offset, uint32_t destination_utc_offset) {
uint32_t timestamp = watch_utility_date_time_to_unix_time(date_time, origin_utc_offset);
return watch_utility_date_time_from_unix_time(timestamp, destination_utc_offset);
}
watch_duration_t watch_utility_seconds_to_duration(uint32_t seconds) {
watch_duration_t retval;
retval.seconds = (seconds % 60);
retval.minutes = (seconds % 3600) / 60;
retval.hours = (seconds % 86400) / 3600;
retval.days = seconds / 86400;
return retval;
}
bool watch_utility_convert_to_12_hour(watch_date_time *date_time) {
bool is_pm = date_time->unit.hour > 11;
date_time->unit.hour %= 12;
if (date_time->unit.hour == 0) date_time->unit.hour = 12;
return is_pm;
}
float watch_utility_thermistor_temperature(uint16_t value, bool highside, float b_coefficient, float nominal_temperature, float nominal_resistance, float series_resistance) {
float reading = (float)value;
if (highside) {
reading = (1023.0 * series_resistance) / (reading / 64.0);
reading -= series_resistance;
} else {
reading = series_resistance / (65535.0 / value - 1.0);
}
reading = reading / nominal_resistance;
reading = log(reading);
reading /= b_coefficient;
reading += 1.0 / (nominal_temperature + 273.15);
reading = 1.0 / reading;
reading -= 273.15;
return reading;
}
uint32_t watch_utility_offset_timestamp(uint32_t now, int8_t hours, int8_t minutes, int8_t seconds) {
uint32_t new = now;
new += hours * 60 * 60;
new += minutes * 60;
new += seconds;
return new;
}