Sensor Watch Simulator (#35)

* Put something on screen

* Use the 32bit watch_date_time repr to pass from JS

* Implement periodic callbacks

* Clear display on enabling

* Hook up watch_set_led_color() to SVG (green-only)

* Make debug output full-width

* Remove default Emscripten canvas

* Implement sleep and button clicks

* Fix time zone conversion bug in beats-time app

* Clean up warnings

* Fix pin levels

* Set time zone to browser value (if available)

* Add basic backup data saving

* Silence format specifier warnings in both targets

* Remove unnecessary, copied files

* Use RTC pointer to clear callbacks (if available)

* Use preprocessor define to avoid hardcoding MOVEMENT_NUM_FACES

* Change each face to const preprocessor definition

* Remove Intl.DateTimeFormat usage

* Update shell.html title, header

* Add touch start/end event handlers on SVG buttons

* Update shell.html

* Update folder structure (shared, simulator, hardware under watch-library)

* Tease out shared components from watch_slcd

* Clean up simulator watch_slcd.c inline JS calls

* Fix missing newlines at end of file

* Add simulator warnings (except format, unused-paremter)

* Implement remaining watch_rtc functions

* Fix button bug on mouse down then drag out

* Implement remaining watch_slcd functions

* Link keyboard events to buttons (for keys A, L, M)

* Rewrite event handling (mouse, touch, keyboard) in C

* Set explicit text UTF-8 charset in shell.html

* Address PR comments

* Remove unused directories from include paths

1 files changed, 100 insertions, 0 deletions

diff --git a/watch-library/shared/watch/watch_utility.h b/watch-library/shared/watch/watch_utility.h
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+++ b/watch-library/shared/watch/watch_utility.h
@@ -0,0 +1,100 @@
+/*
+ * 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.
+ */
+
+#ifndef _WATCH_UTILITY_H_INCLUDED
+#define _WATCH_UTILITY_H_INCLUDED
+////< @file watch_utility.h
+
+#include "watch.h"
+
+/** @addtogroup utility Utility Functions
+  * @brief This section covers various useful functions that don't fit anywhere else.
+  **/
+/// @{
+/** @brief Returns a two-letter weekday for the given timestamp, suitable for display
+  *        in positions 0-1 of the watch face
+  * @param date_time The watch_date_time whose weekday you want.
+  */
+const char * watch_utility_get_weekday(watch_date_time date_time);
+
+/** @brief Returns the UNIX time (seconds since 1970) for a given date/time in UTC.
+  * @param date_time The watch_date_time that you wish to convert.
+  * @param year The year of the date you wish to convert.
+  * @param month The month of the date you wish to convert.
+  * @param day The day of the date you wish to convert.
+  * @param hour The hour of the date you wish to convert.
+  * @param minute The minute of the date you wish to convert.
+  * @param second The second of the date you wish to convert.
+  * @param utc_offset The number of seconds that date_time is offset from UTC, or 0 if the time is UTC.
+  * @return A UNIX timestamp for the given date/time and UTC offset.
+  * @note Implemented by Wesley Ellis (tahnok) and based on BSD-licensed code by Josh Haberman:
+  *       https://blog.reverberate.org/2020/05/12/optimizing-date-algorithms.html
+  */
+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);
+
+/** @brief Returns the UNIX time (seconds since 1970) for a given watch_date_time struct.
+  * @param date_time The watch_date_time that you wish to convert.
+  * @param utc_offset The number of seconds that date_time is offset from UTC, or 0 if the time is UTC.
+  * @return A UNIX timestamp for the given watch_date_time and UTC offset.
+  */
+uint32_t watch_utility_date_time_to_unix_time(watch_date_time date_time, uint32_t utc_offset);
+
+/** @brief Returns the UNIX time (seconds since 1970) for a given watch_date_time struct.
+  * @param timestamp The UNIX timestamp that you wish to convert.
+  * @param utc_offset The number of seconds that you wish date_time to be offset from UTC.
+  * @return A watch_date_time for the given UNIX timestamp and UTC offset, or if outside the range that
+  *         watch_date_time can represent, a watch_date_time with all fields set to 0.
+  * @note Adapted from MIT-licensed code from musl, Copyright © 2005-2014 Rich Felker, et al.:
+  *       https://github.com/esmil/musl/blob/1cc81f5cb0df2b66a795ff0c26d7bbc4d16e13c6/src/time/__secs_to_tm.c
+  */
+watch_date_time watch_utility_date_time_from_unix_time(uint32_t timestamp, uint32_t utc_offset);
+
+/** @brief Converts a time from a given time zone to another time zone.
+  * @param date_time The watch_date_time that you wish to convert
+  * @param origin_utc_offset The number of seconds from UTC in the origin time zone
+  * @param destination_utc_offset The number of seconds from UTC in the destination time zone
+  * @return A watch_date_time for the given UNIX timestamp and UTC offset, or if outside the range that
+  *         watch_date_time can represent, a watch_date_time with all fields set to 0.
+  * @note Adapted from MIT-licensed code from musl, Copyright © 2005-2014 Rich Felker, et al.:
+  *       https://github.com/esmil/musl/blob/1cc81f5cb0df2b66a795ff0c26d7bbc4d16e13c6/src/time/__secs_to_tm.c
+  */
+watch_date_time watch_utility_date_time_convert_zone(watch_date_time date_time, uint32_t origin_utc_offset, uint32_t destination_utc_offset);
+
+/** @brief Returns a temperature in degrees Celsius for a given thermistor voltage divider circuit.
+  * @param value The raw analog reading from the thermistor pin (0-65535)
+  * @param highside True if the thermistor is connected to VCC and the series resistor is connected
+  *                 to GND; false if the thermistor is connected to GND and the series resistor is
+  *                 connected to VCC.
+  * @param b_coefficient From your thermistor's data sheet, the B25/85 coefficient. A typical value
+  *                      will be between 2000 and 5000.
+  * @param nominal_temperature From your thermistor's data sheet, the temperature (in Celsius) at
+  *                            which the thermistor's resistance is at its nominal value.
+  * @param nominal_resistance The thermistor's resistance at the nominal temperature.
+  * @param series_resistance The value of the other resistor in the voltage divider.
+  * @note Ported from Adafruit's MIT-licensed CircuitPython thermistor code, (c) 2017 Scott Shawcroft:
+  *       https://github.com/adafruit/Adafruit_CircuitPython_Thermistor/blob/main/adafruit_thermistor.py
+  */
+float watch_utility_thermistor_temperature(uint16_t value, bool highside, float b_coefficient, float nominal_temperature, float nominal_resistance, float series_resistance);
+
+#endif