9 files changed, 228 insertions, 15 deletions
diff --git a/make.mk b/make.mk
index 1c2a72f4..c9ef6534 100644
--- a/make.mk
+++ b/make.mk
@@ -81,6 +81,7 @@ SRCS += \
   $(TOP)/watch-library/watch/watch_i2c.c \
   $(TOP)/watch-library/watch/watch_uart.c \
   $(TOP)/watch-library/watch/watch_deepsleep.c \
+  $(TOP)/watch-library/watch/watch_utility.c \
   $(TOP)/watch-library/watch/watch_private.c \
   $(TOP)/watch-library/watch/watch.c \
   $(TOP)/watch-library/hal/src/hal_atomic.c \
diff --git a/movement/make/Makefile b/movement/make/Makefile
index 9ff13b59..a937222b 100755
--- a/movement/make/Makefile
+++ b/movement/make/Makefile
@@ -31,6 +31,7 @@ SRCS += \
   ../watch_faces/complications/pulsometer_face.c \
   ../watch_faces/thermistor/thermistor_driver.c \
   ../watch_faces/thermistor/thermistor_readout_face.c \
+  ../watch_faces/thermistor/thermistor_logging_face.c \
   ../watch_faces/demos/character_set_face.c \
   ../watch_faces/complications/beats_face.c \
 
diff --git a/movement/movement_config.h b/movement/movement_config.h
index 22daf2cb..3e911477 100644
--- a/movement/movement_config.h
+++ b/movement/movement_config.h
@@ -6,6 +6,7 @@
 #include "set_time_face.h"
 #include "pulsometer_face.h"
 #include "thermistor_readout_face.h"
+#include "thermistor_logging_face.h"
 #include "character_set_face.h"
 #include "beats_face.h"
 
diff --git a/movement/watch_faces/clock/simple_clock_face.c b/movement/watch_faces/clock/simple_clock_face.c
index e1e82031..9e279d95 100644
--- a/movement/watch_faces/clock/simple_clock_face.c
+++ b/movement/watch_faces/clock/simple_clock_face.c
@@ -1,6 +1,7 @@
 #include <stdlib.h>
 #include "simple_clock_face.h"
 #include "watch.h"
+#include "watch_utility.h"
 
 void simple_clock_face_setup(movement_settings_t *settings, void ** context_ptr) {
     (void) settings;
@@ -19,7 +20,6 @@ void simple_clock_face_activate(movement_settings_t *settings, void *context) {
 }
 
 bool simple_clock_face_loop(movement_event_t event, movement_settings_t *settings, void *context) {
-    const char weekdays[7][3] = {"SA", "SU", "MO", "TU", "WE", "TH", "FR"};
     char buf[11];
     uint8_t pos;
 
@@ -57,9 +57,9 @@ bool simple_clock_face_loop(movement_event_t event, movement_settings_t *setting
                 pos = 0;
                 if (event.event_type == EVENT_LOW_ENERGY_UPDATE) {
                     if (!watch_tick_animation_is_running()) watch_start_tick_animation(500);
-                    sprintf(buf, "%s%2d%2d%02d  ", weekdays[simple_clock_face_get_weekday(date_time.unit.year, date_time.unit.month, date_time.unit.day)], date_time.unit.day, date_time.unit.hour, date_time.unit.minute);
+                    sprintf(buf, "%s%2d%2d%02d  ", watch_utility_get_weekday(date_time), date_time.unit.day, date_time.unit.hour, date_time.unit.minute);
                 } else {
-                    sprintf(buf, "%s%2d%2d%02d%02d", weekdays[simple_clock_face_get_weekday(date_time.unit.year, date_time.unit.month, date_time.unit.day)], date_time.unit.day, date_time.unit.hour, date_time.unit.minute, date_time.unit.second);
+                    sprintf(buf, "%s%2d%2d%02d%02d", watch_utility_get_weekday(date_time), date_time.unit.day, date_time.unit.hour, date_time.unit.minute, date_time.unit.second);
                 }
             }
             watch_display_string(buf, pos);
@@ -83,12 +83,3 @@ void simple_clock_face_resign(movement_settings_t *settings, void *context) {
     (void) settings;
     (void) context;
 }
-
-uint8_t simple_clock_face_get_weekday(uint16_t year, uint16_t month, uint16_t day) {
-    year += 20;
-    if (month <= 2) {
-        month += 12;
-        year--;
-    }
-    return (day + 13 * (month + 1) / 5 + year + year / 4 + 525) % 7;
-}
diff --git a/movement/watch_faces/thermistor/thermistor_logging_face.c b/movement/watch_faces/thermistor/thermistor_logging_face.c
new file mode 100644
index 00000000..1ff20483
--- /dev/null
+++ b/movement/watch_faces/thermistor/thermistor_logging_face.c
@@ -0,0 +1,109 @@
+#include <stdlib.h>
+#include <string.h>
+#include "thermistor_logging_face.h"
+#include "thermistor_driver.h"
+#include "watch.h"
+
+void _thermistor_logging_face_log_data(thermistor_logger_state_t *logger_state) {
+    thermistor_driver_enable();
+    watch_date_time date_time = watch_rtc_get_date_time();
+    size_t pos = logger_state->data_points % THERMISTOR_LOGGING_NUM_DATA_POINTS;
+
+    logger_state->data[pos].timestamp.reg = date_time.reg;
+    logger_state->data[pos].temperature_c = thermistor_driver_get_temperature();
+    logger_state->data_points++;
+
+    thermistor_driver_disable();
+}
+
+void _thermistor_logging_face_update_display(thermistor_logger_state_t *logger_state, bool in_fahrenheit, bool clock_mode_24h) {
+    int8_t pos = (logger_state->data_points - 1 - logger_state->display_index) % THERMISTOR_LOGGING_NUM_DATA_POINTS;
+    char buf[14];
+
+    watch_clear_indicator(WATCH_INDICATOR_24H);
+    watch_clear_indicator(WATCH_INDICATOR_PM);
+    watch_clear_colon();
+
+    if (pos < 0) {
+        sprintf(buf, "TL%2dno dat", logger_state->display_index);
+    } else if (logger_state->ts_ticks) {
+        watch_date_time date_time = logger_state->data[pos].timestamp;
+        watch_set_colon();
+        if (clock_mode_24h) {
+            watch_set_indicator(WATCH_INDICATOR_24H);
+        } else {
+            if (date_time.unit.hour > 11) watch_set_indicator(WATCH_INDICATOR_PM);
+            date_time.unit.hour %= 12;
+            if (date_time.unit.hour == 0) date_time.unit.hour = 12;
+        }
+        sprintf(buf, "AT%2d%2d%02d%02d", date_time.unit.day, date_time.unit.hour, date_time.unit.minute, date_time.unit.second);
+    } else {
+        if (in_fahrenheit) {
+            sprintf(buf, "TL%2d%4.1f#F", logger_state->display_index, logger_state->data[pos].temperature_c * 1.8 + 32.0);
+        } else {
+            sprintf(buf, "TL%2d%4.1f#C", logger_state->display_index, logger_state->data[pos].temperature_c);
+        }
+    }
+
+    watch_display_string(buf, 0);
+}
+
+void thermistor_logging_face_setup(movement_settings_t *settings, void ** context_ptr) {
+    (void) settings;
+    if (*context_ptr == NULL) *context_ptr = malloc(sizeof(thermistor_logger_state_t));
+    memset(*context_ptr, 0, sizeof(thermistor_logger_state_t));
+}
+
+void thermistor_logging_face_activate(movement_settings_t *settings, void *context) {
+    (void) settings;
+    thermistor_logger_state_t *logger_state = (thermistor_logger_state_t *)context;
+    logger_state->display_index = 0;
+    logger_state->ts_ticks = 0;
+}
+
+bool thermistor_logging_face_loop(movement_event_t event, movement_settings_t *settings, void *context) {
+    thermistor_logger_state_t *logger_state = (thermistor_logger_state_t *)context;
+    watch_date_time date_time = watch_rtc_get_date_time();
+    switch (event.event_type) {
+        case EVENT_TIMEOUT:
+            movement_move_to_face(0);
+            break;
+        case EVENT_MODE_BUTTON_UP:
+            movement_move_to_next_face();
+            break;
+        case EVENT_LIGHT_LONG_PRESS:
+            // light button shows the timestamp, but if you need the light, long press it.
+            movement_illuminate_led();
+            break;
+        case EVENT_LIGHT_BUTTON_DOWN:
+            logger_state->ts_ticks = 2;
+            _thermistor_logging_face_update_display(logger_state, settings->bit.use_imperial_units, settings->bit.clock_mode_24h);
+            break;
+        case EVENT_ALARM_BUTTON_DOWN:
+            logger_state->display_index = (logger_state->display_index + 1) % THERMISTOR_LOGGING_NUM_DATA_POINTS;
+            logger_state->ts_ticks = 0;
+            // fall through
+        case EVENT_ACTIVATE:
+            _thermistor_logging_face_update_display(logger_state, settings->bit.use_imperial_units, settings->bit.clock_mode_24h);
+            break;
+        case EVENT_TICK:
+            if (logger_state->ts_ticks && --logger_state->ts_ticks == 0) {
+                _thermistor_logging_face_update_display(logger_state, settings->bit.use_imperial_units, settings->bit.clock_mode_24h);
+            }
+            // this is just temporary for testing: log a data point every 30 seconds.
+            if (date_time.unit.second % 30 == 0 && !logger_state->ts_ticks) {
+                _thermistor_logging_face_log_data(logger_state);
+                _thermistor_logging_face_update_display(logger_state, settings->bit.use_imperial_units, settings->bit.clock_mode_24h);
+            }
+            break;
+        default:
+            break;
+    }
+
+    return true;
+}
+
+void thermistor_logging_face_resign(movement_settings_t *settings, void *context) {
+    (void) settings;
+    (void) context;
+}
diff --git a/movement/watch_faces/thermistor/thermistor_logging_face.h b/movement/watch_faces/thermistor/thermistor_logging_face.h
new file mode 100644
index 00000000..43d441be
--- /dev/null
+++ b/movement/watch_faces/thermistor/thermistor_logging_face.h
@@ -0,0 +1,34 @@
+#ifndef THERMISTOR_LOGGING_FACE_H_
+#define THERMISTOR_LOGGING_FACE_H_
+
+#include "movement.h"
+#include "watch.h"
+
+#define THERMISTOR_LOGGING_NUM_DATA_POINTS (36)
+
+typedef struct {
+    watch_date_time timestamp;
+    float temperature_c;
+} thermistor_logger_data_point_t;
+
+typedef struct {
+    uint8_t display_index;  // the index we are displaying on screen
+    uint8_t ts_ticks;       // when the user taps the LIGHT button, we show the timestamp for a few ticks.
+    int32_t data_points;    // the absolute number of data points logged
+    thermistor_logger_data_point_t data[THERMISTOR_LOGGING_NUM_DATA_POINTS];
+} thermistor_logger_state_t;
+
+void thermistor_logging_face_setup(movement_settings_t *settings, void ** context_ptr);
+void thermistor_logging_face_activate(movement_settings_t *settings, void *context);
+bool thermistor_logging_face_loop(movement_event_t event, movement_settings_t *settings, void *context);
+void thermistor_logging_face_resign(movement_settings_t *settings, void *context);
+
+static const watch_face_t thermistor_logging_face = {
+    thermistor_logging_face_setup,
+    thermistor_logging_face_activate,
+    thermistor_logging_face_loop,
+    thermistor_logging_face_resign,
+    NULL
+};
+
+#endif // THERMISTOR_LOGGING_FACE_H_
diff --git a/movement/watch_faces/thermistor/thermistor_readout_face.h b/movement/watch_faces/thermistor/thermistor_readout_face.h
index 639d00a4..71d15427 100644
--- a/movement/watch_faces/thermistor/thermistor_readout_face.h
+++ b/movement/watch_faces/thermistor/thermistor_readout_face.h
@@ -1,5 +1,5 @@
-#ifndef THERMISTOR_FACE_H_
-#define THERMISTOR_FACE_H_
+#ifndef THERMISTOR_READOUT_FACE_H_
+#define THERMISTOR_READOUT_FACE_H_
 
 #include "movement.h"
 
@@ -16,4 +16,4 @@ static const watch_face_t thermistor_readout_face = {
     NULL
 };
 
-#endif // THERMISTOR_FACE_H_
-\ No newline at end of file
+#endif // THERMISTOR_READOUT_FACE_H_
diff --git a/watch-library/watch/watch_utility.c b/watch-library/watch/watch_utility.c
new file mode 100644
index 00000000..a0f361b4
--- /dev/null
+++ b/watch-library/watch/watch_utility.c
@@ -0,0 +1,35 @@
+/*
+ * 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 "watch_utility.h"
+
+const char * watch_utility_get_weekday(watch_date_time date_time) {
+    static const char weekdays[7][3] = {"SA", "SU", "MO", "TU", "WE", "TH", "FR"};
+    date_time.unit.year += 20;
+    if (date_time.unit.month <= 2) {
+        date_time.unit.month += 12;
+        date_time.unit.year--;
+    }
+    return weekdays[(date_time.unit.day + 13 * (date_time.unit.month + 1) / 5 + date_time.unit.year + date_time.unit.year / 4 + 525) % 7];
+}
diff --git a/watch-library/watch/watch_utility.h b/watch-library/watch/watch_utility.h
new file mode 100644
index 00000000..e8808923
--- /dev/null
+++ b/watch-library/watch/watch_utility.h
@@ -0,0 +1,41 @@
+/*
+ * 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);
+
+#endif