From b0a943c270f78fbf7a0f423277d24fd60b20e63a Mon Sep 17 00:00:00 2001
From: Gergely Polonkai <gergely@polonkai.eu>
Date: Thu, 19 May 2022 08:14:01 +0200
Subject: [PATCH] Calculate day parts based on UTC time instead of local time

---
 src/main.rs | 78 ++++++++++++++++++++++++++++++-----------------------
 1 file changed, 45 insertions(+), 33 deletions(-)

diff --git a/src/main.rs b/src/main.rs
index 9cf987c..8e483c3 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -3,7 +3,7 @@ extern crate smithay_client_toolkit as sctk;
 use std::fmt;
 use std::time::SystemTime;
 
-use chrono::prelude::Local;
+use chrono::prelude::{Local, Utc};
 use chrono::TimeZone;
 use chrono::Timelike;
 use sctk::reexports::client::protocol::{wl_shm, wl_surface};
@@ -251,6 +251,7 @@ fn gen_svg() -> Document {
     let local_timestamp = Local::now();
     let utc_offset = local_timestamp.offset().local_minus_utc();
     let local_time = local_timestamp.time().num_seconds_from_midnight() as i32;
+    let utc_rotation = seconds_to_degrees(utc_offset);
 
     // TODO: Make these configurable
     let lat = 47.655235;
@@ -266,35 +267,35 @@ fn gen_svg() -> Document {
     let moon_phase = moon_illumination.phase * 28.0;
 
     let sun_times = suncalc::get_times(unixtime, lat, long, None);
-    let noon = Local
+    let noon = Utc
         .timestamp_millis(sun_times.solar_noon.0)
         .time()
         .num_seconds_from_midnight() as i32;
-    let midnight = Local
+    let midnight = Utc
         .timestamp_millis(sun_times.nadir.0)
         .time()
         .num_seconds_from_midnight() as i32;
-    let morning_golden_end = Local
+    let morning_golden_end = Utc
         .timestamp_millis(sun_times.golden_hour_end.0)
         .time()
         .num_seconds_from_midnight() as i32;
-    let evening_golden_start = Local
+    let evening_golden_start = Utc
         .timestamp_millis(sun_times.golden_hour.0)
         .time()
         .num_seconds_from_midnight() as i32;
-    let sunrise = Local
+    let sunrise = Utc
         .timestamp_millis(sun_times.sunrise.0)
         .time()
         .num_seconds_from_midnight() as i32;
-    let sunset = Local
+    let sunset = Utc
         .timestamp_millis(sun_times.sunset.0)
         .time()
         .num_seconds_from_midnight() as i32;
-    let dawn = Local
+    let dawn = Utc
         .timestamp_millis(sun_times.dawn.0)
         .time()
         .num_seconds_from_midnight() as i32;
-    let dusk = Local
+    let dusk = Utc
         .timestamp_millis(sun_times.dusk.0)
         .time()
         .num_seconds_from_midnight() as i32;
@@ -367,7 +368,7 @@ fn gen_svg() -> Document {
         "transform",
         format!(
             "rotate({}, {}, {})",
-            seconds_to_degrees(utc_offset),
+            utc_rotation,
             image_width / 2,
             image_width / 2
         ),
@@ -407,7 +408,7 @@ fn gen_svg() -> Document {
             "transform",
             format!(
                 "rotate({}, {}, {})",
-                time_to_degrees(local_time),
+                time_to_degrees(local_time) - time_to_degrees(utc_offset),
                 image_width / 2,
                 image_width / 2
             ),
@@ -429,26 +430,6 @@ fn gen_svg() -> Document {
         .set("cy", image_width / 2)
         .set("r", marker_radius);
 
-    let day_parts_group = Group::new()
-        .set("id", "day-parts")
-        .add(daytime_circle)
-        .add(golden_hour_path)
-        .add(sun_disc)
-        .add(blue_hour_path)
-        .add(nighttime_path)
-        .add(marker_circle);
-
-    let moon_circle = Circle::new()
-        .set("class", "moon-background")
-        .set("cx", image_width / 2)
-        .set("cy", image_width / 2)
-        .set("r", moon_radius);
-
-    let moon_group = Group::new()
-        .set("id", "moon-container")
-        .add(moon_circle)
-        .add(get_moon_path(image_width, moon_radius, moon_phase));
-
     let noon_marker = Line::new()
         .set("class", "mid-marker")
         .set(
@@ -467,6 +448,7 @@ fn gen_svg() -> Document {
         )
         .set("x2", image_width / 2)
         .set("y2", image_width as f32 / 2.0 + marker_radius);
+
     let midnight_marker = Line::new()
         .set("class", "mid-marker")
         .set(
@@ -485,6 +467,38 @@ fn gen_svg() -> Document {
         )
         .set("x2", image_width / 2)
         .set("y2", image_width as f32 / 2.0 + marker_radius);
+
+    let day_parts_group = Group::new()
+        .set("id", "day-parts")
+        .set(
+            "transform",
+            format!(
+                "rotate({}, {}, {})",
+                utc_rotation,
+                image_width / 2,
+                image_width / 2
+            ),
+        )
+        .add(daytime_circle)
+        .add(golden_hour_path)
+        .add(sun_disc)
+        .add(blue_hour_path)
+        .add(nighttime_path)
+        .add(marker_circle)
+        .add(noon_marker)
+        .add(midnight_marker);
+
+    let moon_circle = Circle::new()
+        .set("class", "moon-background")
+        .set("cx", image_width / 2)
+        .set("cy", image_width / 2)
+        .set("r", moon_radius);
+
+    let moon_group = Group::new()
+        .set("id", "moon-container")
+        .add(moon_circle)
+        .add(get_moon_path(image_width, moon_radius, moon_phase));
+
     let dial = Line::new()
         .set("id", "dial")
         .set("class", "dial")
@@ -575,8 +589,6 @@ fn gen_svg() -> Document {
         .add(day_parts_group)
         .add(seasonal_clock)
         .add(moon_group)
-        .add(noon_marker)
-        .add(midnight_marker)
         .add(dial)
         .add(current_hour_group)
 }