From 1ad530127e6217df9597dd5614e863862a7cea01 Mon Sep 17 00:00:00 2001
From: Knyffen <knyffen@gmail.com>
Date: Fri, 31 Jan 2025 18:58:22 +0100
Subject: [PATCH] Initial adjustment for calories burned based on weight

---
 server/src/main.rs              |  4 ++-
 server/src/math/calculations.rs | 46 +++++++++++++++++++++++++++++----
 2 files changed, 44 insertions(+), 6 deletions(-)

diff --git a/server/src/main.rs b/server/src/main.rs
index d39f1dc..55e16b3 100644
--- a/server/src/main.rs
+++ b/server/src/main.rs
@@ -131,11 +131,13 @@ async fn svg_calorie_intake(
 
     let nutrition_val_promise = Nutrition::get_nutrition_hashmap(state.sql_pool.clone());
     let purchases_val_promise = Purchase::get_purchase_rows(state.sql_pool.clone());
+    let weight_val_promise = Weight::get_weight_rows(state.sql_pool.clone());
 
     let nutrition_val = nutrition_val_promise.await?;
     let purchases_val = purchases_val_promise.await?;
+    let weight_val = weight_val_promise.await?;
 
-    let plotfun = math::plot_calories_per_day(nutrition_val, purchases_val);
+    let plotfun = math::plot_calories_per_day(nutrition_val, purchases_val, weight_val);
     Ok(plotting::SVGPlotter::plot(640, 480, plotfun))
 }
 
diff --git a/server/src/math/calculations.rs b/server/src/math/calculations.rs
index 6c6d181..5cc9047 100644
--- a/server/src/math/calculations.rs
+++ b/server/src/math/calculations.rs
@@ -13,6 +13,8 @@ use time::*;
 const MEALS_PER_DAY: f32 = 2.3;
 const SMOOTHING_DAYS: usize = 21;
 const CALORIES_BURNED_PER_DAY: f32 = 2270.;
+const CALORIES_BURNED_PER_DAY_BASE_WEIGHT: f32 = 83.;
+const CALORIES_BURNED_LESS_PER_DAY_PER_KG: f32 = 12.5;
 
 fn time_date_to_chrono_naive_date(d: Date) -> chrono::NaiveDate {
     chrono::NaiveDate::from_ymd_opt(d.year(), d.month() as u32, d.day() as u32).unwrap()
@@ -82,6 +84,7 @@ fn calculate_calories_per_day(
 pub fn plot_calories_per_day(
     nutrition_map: HashMap<u32, Nutrition>,
     purchases: Vec<my_structs::Purchase>,
+    weight: Vec<my_structs::Weight>,
 ) -> plotting::SVGPlotFun {
     let (mindate, calorie_days) = calculate_calories_per_day(nutrition_map, purchases);
 
@@ -99,6 +102,28 @@ pub fn plot_calories_per_day(
         .reduce(|a, b| a.max(b))
         .unwrap();
 
+    let weight_dates: Vec<f32> = weight
+        .iter()
+        .map(|w| (w.datetime.date() - mindate).whole_days() as f32)
+        .collect();
+    let weight_values: Vec<f32> = weight.iter().map(|w| w.weight).collect();
+    let weight_days = interp_slice(
+        &weight_dates,
+        &weight_values,
+        &(0..calorie_days.len())
+            .map(|x| x as f32)
+            .collect::<Vec<f32>>(),
+        &InterpMode::FirstLast,
+    );
+    let calories_burned_per_day_days: Vec<f32> = weight_days
+        .iter()
+        .map(|weight| {
+            CALORIES_BURNED_PER_DAY
+                + CALORIES_BURNED_LESS_PER_DAY_PER_KG
+                    * (weight - CALORIES_BURNED_PER_DAY_BASE_WEIGHT)
+        })
+        .collect();
+
     let plotfun = Box::new(move |root: plotting::SVGPlotRoot| {
         root.fill(&WHITE).unwrap();
         let mut chart = ChartBuilder::on(&root)
@@ -128,10 +153,17 @@ pub fn plot_calories_per_day(
 
         chart
             .draw_series(LineSeries::new(
-                vec![
-                    (mindate_chrono, CALORIES_BURNED_PER_DAY),
-                    (maxdate_chrono, CALORIES_BURNED_PER_DAY),
-                ],
+                calories_burned_per_day_days
+                    .iter()
+                    .enumerate()
+                    .map(|(i, cal)| {
+                        (
+                            mindate_chrono
+                                .checked_add_days(chrono::Days::new(i.try_into().unwrap()))
+                                .unwrap(),
+                            *cal,
+                        )
+                    }),
                 BLACK.stroke_width(2),
             ))
             .unwrap()
@@ -206,7 +238,11 @@ pub fn plot_weight_loss(
         .iter()
         .enumerate()
         .scan(0., |deficit, (i, &calories)| {
-            *deficit += calories - CALORIES_BURNED_PER_DAY - running_days[i];
+            *deficit += calories
+                - (CALORIES_BURNED_PER_DAY
+                    + CALORIES_BURNED_LESS_PER_DAY_PER_KG
+                        * (weight_days[i] - CALORIES_BURNED_PER_DAY_BASE_WEIGHT))
+                - running_days[i];
             Some(*deficit)
         })
         .collect();