From df706890beccb6adfa6234771f0f135f2b3133de Mon Sep 17 00:00:00 2001
From: zenonet <git@zenonet.de>
Date: Thu, 18 Sep 2025 21:30:12 +0200
Subject: [PATCH] made the period lookup const

---
 src/main.rs | 38 +++++++++++++++-----------------------
 1 file changed, 15 insertions(+), 23 deletions(-)

diff --git a/src/main.rs b/src/main.rs
index e4ce5ef..c2d706b 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -184,19 +184,21 @@ fn draw_layout(display: &mut epd_waveshare::epd7in5_v2::Display7in5, timetable:
 }
 
 
-fn get_school_period(time: NaiveTime) -> u8{
-    let lookup: [NaiveTime; 8] = [
-        (NaiveTime::from_hms_opt(8, 45, 0).unwrap()),
-        (NaiveTime::from_hms_opt(9, 35, 0).unwrap()),
-        (NaiveTime::from_hms_opt(10, 40, 0).unwrap()),
-        (NaiveTime::from_hms_opt(11, 30, 0).unwrap()),
-        (NaiveTime::from_hms_opt(12, 40, 0).unwrap()),
-        (NaiveTime::from_hms_opt(13, 30, 0).unwrap()),
-        (NaiveTime::from_hms_opt(14, 25, 0).unwrap()),
-        (NaiveTime::from_hms_opt(15, 15, 0).unwrap()),
-    ];
+const PERIOD_LOOKUP: [NaiveTime; 8] = [
+    (NaiveTime::from_hms_opt(8, 45, 0).unwrap()),
+    (NaiveTime::from_hms_opt(9, 35, 0).unwrap()),
+    (NaiveTime::from_hms_opt(10, 40, 0).unwrap()),
+    (NaiveTime::from_hms_opt(11, 30, 0).unwrap()),
+    (NaiveTime::from_hms_opt(12, 40, 0).unwrap()),
+    (NaiveTime::from_hms_opt(13, 30, 0).unwrap()),
+    (NaiveTime::from_hms_opt(14, 25, 0).unwrap()),
+    (NaiveTime::from_hms_opt(15, 15, 0).unwrap()),
+];
 
-    for (index, period_time) in lookup.iter().enumerate(){
+fn get_school_period(time: NaiveTime) -> u8{
+
+
+    for (index, period_time) in PERIOD_LOOKUP.iter().enumerate(){
         if time < *period_time{
             return index as u8;
         }
@@ -206,16 +208,6 @@ fn get_school_period(time: NaiveTime) -> u8{
 
 
 fn transform_lessons(lessons: Vec<Lesson>) -> Box<Timetable>{
-    let lookup: [NaiveTime; 8] = [
-        (NaiveTime::from_hms_opt(8, 45, 0).unwrap()),
-        (NaiveTime::from_hms_opt(9, 35, 0).unwrap()),
-        (NaiveTime::from_hms_opt(10, 40, 0).unwrap()),
-        (NaiveTime::from_hms_opt(11, 30, 0).unwrap()),
-        (NaiveTime::from_hms_opt(12, 40, 0).unwrap()),
-        (NaiveTime::from_hms_opt(13, 30, 0).unwrap()),
-        (NaiveTime::from_hms_opt(14, 25, 0).unwrap()),
-        (NaiveTime::from_hms_opt(15, 15, 0).unwrap()),
-    ];
 
     let mut table: Box<[[Option<Lesson>; 8]; 5]> = Box::new([0u8; 5].map(|_| [0u8; 8].map(|_| Option::<Lesson>::None)));
 
@@ -223,7 +215,7 @@ fn transform_lessons(lessons: Vec<Lesson>) -> Box<Timetable>{
         let day_idx = lesson.date.weekday().num_days_from_monday() as usize;
 
         let mut l = Cow::<Lesson>::Owned(lesson);
-        for (period_idx, time) in lookup.iter().enumerate(){
+        for (period_idx, time) in PERIOD_LOOKUP.iter().enumerate(){
             if l.start_time.0 < *time && &l.end_time.0 >= time{
                 table[day_idx][period_idx] = Some(l.into_owned());
                 l = Cow::Borrowed(&table[day_idx][period_idx].as_ref().unwrap());