From cee2e368dc7cc05d180997365d8243004c53d774 Mon Sep 17 00:00:00 2001
From: Camden Dixie O'Brien <cdo@wip.sh>
Date: Mon, 15 May 2023 17:31:23 +0100
Subject: [PATCH] Flesh out time module

---
 components/display/display.c               |  4 +--
 components/time/CMakeLists.txt             |  4 +--
 components/time/time.c                     | 15 ----------
 components/time/time_manager.c             | 33 ++++++++++++++++++++++
 components/time/{time.h => time_manager.h} |  8 +++---
 5 files changed, 41 insertions(+), 23 deletions(-)
 delete mode 100644 components/time/time.c
 create mode 100644 components/time/time_manager.c
 rename components/time/{time.h => time_manager.h} (70%)

diff --git a/components/display/display.c b/components/display/display.c
index 22f8424..c0be9f3 100644
--- a/components/display/display.c
+++ b/components/display/display.c
@@ -7,7 +7,7 @@
 
 #include "display_driver.h"
 #include "fatal.h"
-#include "time.h"
+#include "time_manager.h"
 
 #include "esp_log.h"
 #include "esp_timer.h"
@@ -57,7 +57,7 @@ static void show_time(unsigned hour, unsigned minute)
 static void update_time(void *arg)
 {
 	(void)arg;
-	const Time time = time_get();
+	const Time time = get_time();
 	show_time(time.hour, time.minute);
 }
 
diff --git a/components/time/CMakeLists.txt b/components/time/CMakeLists.txt
index 956f92b..130f44d 100644
--- a/components/time/CMakeLists.txt
+++ b/components/time/CMakeLists.txt
@@ -1,5 +1,5 @@
 idf_component_register(
-  SRCS "time.c"
+  SRCS "time_manager.c"
   INCLUDE_DIRS "."
-  REQUIRES
+  REQUIRES config
 )
diff --git a/components/time/time.c b/components/time/time.c
deleted file mode 100644
index d514eaf..0000000
--- a/components/time/time.c
+++ /dev/null
@@ -1,15 +0,0 @@
-/*
- * SPDX-License-Identifier: AGPL-3.0-only
- * Copyright (c) Camden Dixie O'Brien
- */
-
-#include "time.h"
-
-void time_init(void)
-{
-}
-
-Time time_get(void)
-{
-	return (Time){ .hour = 13, .minute = 37 };
-}
diff --git a/components/time/time_manager.c b/components/time/time_manager.c
new file mode 100644
index 0000000..b8cf755
--- /dev/null
+++ b/components/time/time_manager.c
@@ -0,0 +1,33 @@
+/*
+ * SPDX-License-Identifier: AGPL-3.0-only
+ * Copyright (c) Camden Dixie O'Brien
+ */
+
+#include "time_manager.h"
+
+#include "config.h"
+
+#include <time.h>
+
+static void handle_timezone_update(const char *timezone)
+{
+	setenv("TZ", timezone, 1);
+	tzset();
+}
+
+void time_manager_init(void)
+{
+	char timezone[CONFIG_MAX_VALUE_SIZE];
+	(void)config_get_timezone(timezone, CONFIG_MAX_VALUE_SIZE);
+	handle_timezone_update(timezone);
+
+	config_add_timezone_callback(&handle_timezone_update);
+}
+
+Time get_time(void)
+{
+	const time_t now = time(NULL);
+	struct tm timeinfo;
+	(void)localtime_r(&now, &timeinfo);
+	return (Time) { .hour = timeinfo.tm_hour, .minute = timeinfo.tm_min };
+}
diff --git a/components/time/time.h b/components/time/time_manager.h
similarity index 70%
rename from components/time/time.h
rename to components/time/time_manager.h
index 843d9c1..41e83a2 100644
--- a/components/time/time.h
+++ b/components/time/time_manager.h
@@ -3,8 +3,8 @@
  * Copyright (c) Camden Dixie O'Brien
  */
 
-#ifndef TIME_H
-#define TIME_H
+#ifndef TIME_MANAGER_H
+#define TIME_MANAGER_H
 
 typedef struct {
 	unsigned hour;
@@ -14,11 +14,11 @@ typedef struct {
 /**
  * Initialize the time module.
  */
-void time_init(void);
+void time_manager_init(void);
 
 /**
  * Get the current time.
  */
-Time time_get(void);
+Time get_time(void);
 
 #endif